Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.
A ubiquitous family of proteins that transport PHOSPHOLIPIDS such as PHOSPHATIDYLINOSITOL and PHOSPHATIDYLCHOLINE between membranes. They play an important role in phospholipid metabolism during vesicular transport and SIGNAL TRANSDUCTION.
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to an ethanolamine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and ethanolamine and 2 moles of fatty acids.
Lipids, predominantly phospholipids, cholesterol and small amounts of glycolipids found in membranes including cellular and intracellular membranes. These lipids may be arranged in bilayers in the membranes with integral proteins between the layers and peripheral proteins attached to the outside. Membrane lipids are required for active transport, several enzymatic activities and membrane formation.
Phospholipids which have an alcohol moiety in ethereal linkage with a saturated or unsaturated aliphatic alcohol. They are usually derivatives of phosphoglycerols or phosphatidates. The other two alcohol groups of the glycerol backbone are usually in ester linkage. These compounds are widely distributed in animal tissues.
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a serine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and serine and 2 moles of fatty acids.
Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
A nitrogen-free class of lipids present in animal and particularly plant tissues and composed of one mole of glycerol and 1 or 2 moles of phosphatidic acid. Members of this group differ from one another in the nature of the fatty acids released on hydrolysis.
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
Acidic phospholipids composed of two molecules of phosphatidic acid covalently linked to a molecule of glycerol. They occur primarily in mitochondrial inner membranes and in bacterial plasma membranes. They are the main antigenic components of the Wassermann-type antigen that is used in nontreponemal SYPHILIS SERODIAGNOSIS.
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to the hexahydroxy alcohol, myo-inositol. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid, myo-inositol, and 2 moles of fatty acids.
Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A class of enzymes that catalyze the hydrolysis of phosphoglycerides or glycerophosphatidates. EC 3.1.-.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.
A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS.
The rate dynamics in chemical or physical systems.
Phospholipases that hydrolyze one of the acyl groups of phosphoglycerides or glycerophosphatidates.
Synthetic phospholipid used in liposomes and lipid bilayers to study biological membranes. It is also a major constituent of PULMONARY SURFACTANTS.
Phospholipases that hydrolyze the acyl group attached to the 2-position of PHOSPHOGLYCERIDES.
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
Fatty acid derivatives of glycerophosphates. They are composed of glycerol bound in ester linkage with 1 mole of phosphoric acid at the terminal 3-hydroxyl group and with 2 moles of fatty acids at the other two hydroxyl groups.
A synthetic phospholipid used in liposomes and lipid bilayers for the study of biological membranes.
Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.
Derivatives of PHOSPHATIDYLCHOLINES obtained by their partial hydrolysis which removes one of the fatty acid moieties.
FATTY ACIDS in which the carbon chain contains one or more double or triple carbon-carbon bonds.
A basic constituent of lecithin that is found in many plants and animal organs. It is important as a precursor of acetylcholine, as a methyl donor in various metabolic processes, and in lipid metabolism.
GLYCEROPHOSPHOLIPIDS in which one of the two acyl chains is attached to glycerol with an ether alkenyl linkage instead of an ester as with the other glycerophospholipids.
Physiological processes in biosynthesis (anabolism) and degradation (catabolism) of LIPIDS.
Substances and drugs that lower the SURFACE TENSION of the mucoid layer lining the PULMONARY ALVEOLI.
The motion of phospholipid molecules within the lipid bilayer, dependent on the classes of phospholipids present, their fatty acid composition and degree of unsaturation of the acyl chains, the cholesterol concentration, and temperature.
An isomer of glucose that has traditionally been considered to be a B vitamin although it has an uncertain status as a vitamin and a deficiency syndrome has not been identified in man. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1379) Inositol phospholipids are important in signal transduction.
Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.
An unsaturated, essential fatty acid. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is formed by the synthesis from dietary linoleic acid and is a precursor in the biosynthesis of prostaglandins, thromboxanes, and leukotrienes.
A component of PHOSPHATIDYLCHOLINES or LECITHINS, in which the two hydroxy groups of GLYCEROL are esterified with fatty acids. (From Stedman, 26th ed) It counteracts the effects of urea on enzymes and other macromolecules.
Protein-lipid combinations abundant in brain tissue, but also present in a wide variety of animal and plant tissues. In contrast to lipoproteins, they are insoluble in water, but soluble in a chloroform-methanol mixture. The protein moiety has a high content of hydrophobic amino acids. The associated lipids consist of a mixture of GLYCEROPHOSPHATES; CEREBROSIDES; and SULFOGLYCOSPHINGOLIPIDS; while lipoproteins contain PHOSPHOLIPIDS; CHOLESTEROL; and TRIGLYCERIDES.
An enzyme that catalyses three sequential METHYLATION reactions for conversion of phosphatidylethanolamine to PHOSPHATIDYLCHOLINE.
The characteristic three-dimensional shape of a molecule.
A viscous, hygroscopic amino alcohol with an ammoniacal odor. It is widely distributed in biological tissue and is a component of lecithin. It is used as a surfactant, fluorimetric reagent, and to remove CO2 and H2S from natural gas and other gases.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
C22-unsaturated fatty acids found predominantly in FISH OILS.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.
The process of cleaving a chemical compound by the addition of a molecule of water.
The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.
A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Diglycerides are a type of glyceride, specifically a form of lipid, that contains two fatty acid chains linked to a glycerol molecule by ester bonds.
An enzyme localized predominantly within the plasma membrane of lymphocytes. It catalyzes the transfer of long-chain fatty acids, preferentially unsaturated fatty acids, to lysophosphatides with the formation of 1,2-diacylglycero-3-phosphocholine and CoA. EC 2.3.1.23.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Measurement of the intensity and quality of fluorescence.
An enzyme that catalyzes the formation of phosphatidylserine and CMP from CDPdiglyceride plus serine. EC 2.7.8.8.
Purifying or cleansing agents, usually salts of long-chain aliphatic bases or acids, that exert cleansing (oil-dissolving) and antimicrobial effects through a surface action that depends on possessing both hydrophilic and hydrophobic properties.
Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.
A trihydroxy sugar alcohol that is an intermediate in carbohydrate and lipid metabolism. It is used as a solvent, emollient, pharmaceutical agent, and sweetening agent.
Arachidonic acids are polyunsaturated fatty acids, specifically a type of omega-6 fatty acid, that are essential for human nutrition and play crucial roles in various biological processes, including inflammation, immunity, and cell signaling. They serve as precursors to eicosanoids, which are hormone-like substances that mediate a wide range of physiological responses.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Triglycerides are the most common type of fat in the body, stored in fat cells and used as energy; they are measured in blood tests to assess heart disease risk, with high levels often resulting from dietary habits, obesity, physical inactivity, smoking, and alcohol consumption.
Derivatives of phosphatidic acid in which the hydrophobic regions are composed of two fatty acids and a polar alcohol is joined to the C-3 position of glycerol through a phosphodiester bond. They are named according to their polar head groups, such as phosphatidylcholine and phosphatidylethanolamine.
A group of fatty acids that contain 18 carbon atoms and a double bond at the omega 9 carbon.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
The most abundant protein component of HIGH DENSITY LIPOPROTEINS or HDL. This protein serves as an acceptor for CHOLESTEROL released from cells thus promoting efflux of cholesterol to HDL then to the LIVER for excretion from the body (reverse cholesterol transport). It also acts as a cofactor for LECITHIN CHOLESTEROL ACYLTRANSFERASE that forms CHOLESTEROL ESTERS on the HDL particles. Mutations of this gene APOA1 cause HDL deficiency, such as in FAMILIAL ALPHA LIPOPROTEIN DEFICIENCY DISEASE and in some patients with TANGIER DISEASE.
A fluorescent compound that emits light only in specific configurations in certain lipid media. It is used as a tool in the study of membrane lipids.
Single membrane vesicles, generally made of PHOSPHOLIPIDS.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A phosphoinositide present in all eukaryotic cells, particularly in the plasma membrane. It is the major substrate for receptor-stimulated phosphoinositidase C, with the consequent formation of inositol 1,4,5-triphosphate and diacylglycerol, and probably also for receptor-stimulated inositol phospholipid 3-kinase. (Kendrew, The Encyclopedia of Molecular Biology, 1994)
GLYCEROL esterified with FATTY ACIDS.
A group of 16-carbon fatty acids that contain no double bonds.
A phospholipase that hydrolyzes the acyl group attached to the 1-position of PHOSPHOGLYCERIDES.
A class of enzymes that transfers substituted phosphate groups. EC 2.7.8.
Transport proteins that carry specific substances in the blood or across cell membranes.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Eighteen-carbon essential fatty acids that contain two double bonds.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
Fatty acid esters of cholesterol which constitute about two-thirds of the cholesterol in the plasma. The accumulation of cholesterol esters in the arterial intima is a characteristic feature of atherosclerosis.
Characteristics or attributes of the outer boundaries of objects, including molecules.
Any salt or ester of glycerophosphoric acid.
Derivatives of PHOSPHATIDIC ACIDS that lack one of its fatty acyl chains due to its hydrolytic removal.
A benzofuran derivative used as a protein reagent since the terminal N-NBD-protein conjugate possesses interesting fluorescence and spectral properties. It has also been used as a covalent inhibitor of both beef heart mitochondrial ATPase and bacterial ATPase.
The addition of an organic acid radical into a molecule.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Measurement of the polarization of fluorescent light from solutions or microscopic specimens. It is used to provide information concerning molecular size, shape, and conformation, molecular anisotropy, electronic energy transfer, molecular interaction, including dye and coenzyme binding, and the antigen-antibody reaction.
An enzyme that transfers acyl groups from acyl-CoA to glycerol-3-phosphate to form monoglyceride phosphates. It acts only with CoA derivatives of fatty acids of chain length above C-10. Also forms diglyceride phosphates. EC 2.3.1.15.
Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.
Enzymes from the transferase class that catalyze the transfer of acyl groups from donor to acceptor, forming either esters or amides. (From Enzyme Nomenclature 1992) EC 2.3.
An enzyme found mostly in plant tissue. It hydrolyzes glycerophosphatidates with the formation of a phosphatidic acid and a nitrogenous base such as choline. This enzyme also catalyzes transphosphatidylation reactions. EC 3.1.4.4.
Calcium and magnesium salts used therapeutically in hepatobiliary dysfunction.
The force acting on the surface of a liquid, tending to minimize the area of the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Family of calcium- and phospholipid-binding proteins which are structurally related and exhibit immunological cross-reactivity. Each member contains four homologous 70-kDa repeats. The annexins are differentially distributed in vertebrate tissues (and lower eukaryotes) and appear to be involved in MEMBRANE FUSION and SIGNAL TRANSDUCTION.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
An enzyme that catalyzes the synthesis of phosphatidylcholines from CDPcholine and 1,2-diacylglycerols. EC 2.7.8.2.
Nonionic surfactant mixtures varying in the number of repeating ethoxy (oxy-1,2-ethanediyl) groups. They are used as detergents, emulsifiers, wetting agents, defoaming agents, etc. Octoxynol-9, the compound with 9 repeating ethoxy groups, is a spermatocide.
Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.
Important polyunsaturated fatty acid found in fish oils. It serves as the precursor for the prostaglandin-3 and thromboxane-3 families. A diet rich in eicosapentaenoic acid lowers serum lipid concentration, reduces incidence of cardiovascular disorders, prevents platelet aggregation, and inhibits arachidonic acid conversion into the thromboxane-2 and prostaglandin-2 families.
Donor of choline in biosynthesis of choline-containing phosphoglycerides.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
An enzyme that catalyzes the formation of PHOSPHATIDYLINOSITOL and CMP from CDP-DIACYLGLYCEROL and MYOINOSITOL.
The ester of diacylglycerol with the terminal phosphate of cytidine diphosphate. It serves as an intermediate in the biosynthesis of phosphatidylethanolamine and phosphatidylserine in bacteria.
A subclass of phospholipases that hydrolyze the phosphoester bond found in the third position of GLYCEROPHOSPHOLIPIDS. Although the singular term phospholipase C specifically refers to an enzyme that catalyzes the hydrolysis of PHOSPHATIDYLCHOLINE (EC 3.1.4.3), it is commonly used in the literature to refer to broad variety of enzymes that specifically catalyze the hydrolysis of PHOSPHATIDYLINOSITOLS.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
An unsaturated fatty acid that is the most widely distributed and abundant fatty acid in nature. It is used commercially in the preparation of oleates and lotions, and as a pharmaceutical solvent. (Stedman, 26th ed)
A protein of the annexin family isolated from human PLACENTA and other tissues. It inhibits cytosolic PHOSPHOLIPASE A2, and displays anticoagulant activity.
Elements of limited time intervals, contributing to particular results or situations.
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
Inorganic salts of phosphoric acid.
A change of a substance from one form or state to another.
Any compound containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety such as an acylglycerol (see GLYCERIDES), a sphingoid, a ceramide (CERAMIDES) (N-acylsphingoid) or a prenyl phosphate. (From IUPAC's webpage)
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
Salts and esters of the 12-carbon saturated monocarboxylic acid--lauric acid.
A complex mixture of PHOSPHOLIPIDS; GLYCOLIPIDS; and TRIGLYCERIDES; with substantial amounts of PHOSPHATIDYLCHOLINES; PHOSPHATIDYLETHANOLAMINES; and PHOSPHATIDYLINOSITOLS, which are sometimes loosely termed as 1,2-diacyl-3-phosphocholines. Lecithin is a component of the CELL MEMBRANE and commercially extracted from SOYBEANS and EGG YOLK. The emulsifying and surfactant properties are useful in FOOD ADDITIVES and for forming organogels (GELS).
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A plasma protein that is the inactive precursor of thrombin. It is converted to thrombin by a prothrombin activator complex consisting of factor Xa, factor V, phospholipid, and calcium ions. Deficiency of prothrombin leads to hypoprothrombinemia.
The physical characteristics and processes of biological systems.
AMINO ALCOHOLS containing the ETHANOLAMINE; (-NH2CH2CHOH) group and its derivatives.
A doubly unsaturated fatty acid, occurring widely in plant glycosides. It is an essential fatty acid in mammalian nutrition and is used in the biosynthesis of prostaglandins and cell membranes. (From Stedman, 26th ed)
A group of fatty acids, often of marine origin, which have the first unsaturated bond in the third position from the omega carbon. These fatty acids are believed to reduce serum triglycerides, prevent insulin resistance, improve lipid profile, prolong bleeding times, reduce platelet counts, and decrease platelet adhesiveness.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
Phosphatidylinositols in which one or more alcohol group of the inositol has been substituted with a phosphate group.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
Long chain organic acid molecules that must be obtained from the diet. Examples are LINOLEIC ACIDS and LINOLENIC ACIDS.
Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics.
Compounds possessing both a hydroxyl (-OH) and an amino group (-NH2).
Tritium is an isotope of hydrogen (specifically, hydrogen-3) that contains one proton and two neutrons in its nucleus, making it radioactive with a half-life of about 12.3 years, and is used in various applications including nuclear research, illumination, and dating techniques due to its low energy beta decay.
Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.
A phospholipid derivative formed by PLATELETS; BASOPHILS; NEUTROPHILS; MONOCYTES; and MACROPHAGES. It is a potent platelet aggregating agent and inducer of systemic anaphylactic symptoms, including HYPOTENSION; THROMBOCYTOPENIA; NEUTROPENIA; and BRONCHOCONSTRICTION.
A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A 44-kDa highly glycosylated plasma protein that binds phospholipids including CARDIOLIPIN; APOLIPOPROTEIN E RECEPTOR; membrane phospholipids, and other anionic phospholipid-containing moieties. It plays a role in coagulation and apoptotic processes. Formerly known as apolipoprotein H, it is an autoantigen in patients with ANTIPHOSPHOLIPID ANTIBODIES.
Steroids with a hydroxyl group at C-3 and most of the skeleton of cholestane. Additional carbon atoms may be present in the side chain. (IUPAC Steroid Nomenclature, 1987)
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
An emulsifying agent produced in the LIVER and secreted into the DUODENUM. Its composition includes BILE ACIDS AND SALTS; CHOLESTEROL; and ELECTROLYTES. It aids DIGESTION of fats in the duodenum.
Activated form of factor V. It is an essential cofactor for the activation of prothrombin catalyzed by factor Xa.
Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.
Established cell cultures that have the potential to propagate indefinitely.
A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A group of peptide antibiotics from BACILLUS brevis. Gramicidin C or S is a cyclic, ten-amino acid polypeptide and gramicidins A, B, D are linear. Gramicidin is one of the two principal components of TYROTHRICIN.
Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.
Storage-stable glycoprotein blood coagulation factor that can be activated to factor Xa by both the intrinsic and extrinsic pathways. A deficiency of factor X, sometimes called Stuart-Prower factor deficiency, may lead to a systemic coagulation disorder.
Cytoplasm stored in an egg that contains nutritional reserves for the developing embryo. It is rich in polysaccharides, lipids, and proteins.
The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.
Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
A naphthalene derivative with carcinogenic action.
Oils high in unsaturated fats extracted from the bodies of fish or fish parts, especially the LIVER. Those from the liver are usually high in VITAMIN A. The oils are used as DIETARY SUPPLEMENTS. They are also used in soaps and detergents and as protective coatings.
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Proteins prepared by recombinant DNA technology.
Proteins found in the LUNG that act as PULMONARY SURFACTANTS.
A lipoprotein-associated PHOSPHOLIPASE A2 which modulates the action of PLATELET ACTIVATING FACTOR by hydrolyzing the SN-2 ester bond to yield the biologically inactive lyso-platelet-activating factor. It has specificity for phospholipid substrates with short-chain residues at the SN-2 position, but inactive against long-chain phospholipids. Deficiency in this enzyme is associated with many diseases including ASTHMA, and HYPERCHOLESTEROLEMIA.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
Peroxides produced in the presence of a free radical by the oxidation of unsaturated fatty acids in the cell in the presence of molecular oxygen. The formation of lipid peroxides results in the destruction of the original lipid leading to the loss of integrity of the membranes. They therefore cause a variety of toxic effects in vivo and their formation is considered a pathological process in biological systems. Their formation can be inhibited by antioxidants, such as vitamin E, structural separation or low oxygen tension.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).
An enzyme that catalyzes the formation of myo-inositol-1-phosphate from glucose-6-phosphate in the presence of NAD. EC 5.5.1.4.
Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.
Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
A common saturated fatty acid found in fats and waxes including olive oil, palm oil, and body lipids.
Activated form of factor X that participates in both the intrinsic and extrinsic pathways of blood coagulation. It catalyzes the conversion of prothrombin to thrombin in conjunction with other cofactors.
GLYCEROL esterified with a single acyl (FATTY ACIDS) chain.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
FATTY ACIDS found in the plasma that are complexed with SERUM ALBUMIN for transport. These fatty acids are not in glycerol ester form.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
An enzyme that catalyzes the transfer of cytidylate (CMP) to choline phosphate to form CDPcholine. It is the rate-limiting enzyme in the choline pathway for the biosynthesis of phosphatidylcholine. Its activity is increased by glucocorticoids. EC 2.7.7.15.
A calcium-independent phospholipase A2 group that may play a role in membrane phospholipid remodeling and homeostasis by controling the levels of PHOSPHATIDYLCHOLINE in mammalian cell membranes.
Fats present in food, especially in animal products such as meat, meat products, butter, ghee. They are present in lower amounts in nuts, seeds, and avocados.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
Preparation for electron microscopy of minute replicas of exposed surfaces of the cell which have been ruptured in the frozen state. The specimen is frozen, then cleaved under high vacuum at the same temperature. The exposed surface is shadowed with carbon and platinum and coated with carbon to obtain a carbon replica.
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
An abundant pulmonary surfactant-associated protein that binds to a variety of lung pathogens, resulting in their opsinization. It also stimulates MACROPHAGES to undergo PHAGOCYTOSIS of microorganisms. Surfactant protein A contains a N-terminal collagen-like domain and a C-terminal lectin domain that are characteristic of members of the collectin family of proteins.
An enzyme that catalyzes the hydrolysis of a single fatty acid ester bond in lysoglycerophosphatidates with the formation of glyceryl phosphatidates and a fatty acid. EC 3.1.1.5.
(Z)-9-Octadecenoic acid 1,2,3-propanetriyl ester.
A group of compounds that are derivatives of octadecanoic acid which is one of the most abundant fatty acids found in animal lipids. (Stedman, 25th ed)
A fatty acid that is found in plants and involved in the formation of prostaglandins.
The 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholanic acid family of bile acids in man, usually conjugated with glycine or taurine. They act as detergents to solubilize fats for intestinal absorption, are reabsorbed by the small intestine, and are used as cholagogues and choleretics.
Conditions characterized by abnormal lipid deposition due to disturbance in lipid metabolism, such as hereditary diseases involving lysosomal enzymes required for lipid breakdown. They are classified either by the enzyme defect or by the type of lipid involved.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
An enzyme that catalyzes reversibly the transfer of phosphoethanolamine from CDP-ethanolamine to diacylglycerol to yield phosphatidylethanolamine (cephalin) and CMP. The enzyme is found in the endoplasmic reticulum. EC 2.7.8.1.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Steroid acids and salts. The primary bile acids are derived from cholesterol in the liver and usually conjugated with glycine or taurine. The secondary bile acids are further modified by bacteria in the intestine. They play an important role in the digestion and absorption of fat. They have also been used pharmacologically, especially in the treatment of gallstones.
The accumulation of an electric charge on a object
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.

Characterization and expression of the cDNA encoding a new kind of phospholipid transfer protein, the phosphatidylglycerol/phosphatidylinositol transfer protein from Aspergillus oryzae: evidence of a putative membrane targeted phospholipid transfer protein in fungi. (1/11419)

The full-length cDNA of a phospholipid transfer protein (PLTP) was isolated from Aspergillus oryzae by a RACE-PCR procedure using degenerated primer pool selected from the N-terminal sequence of the purified phosphatidylinositol/phosphatidylglycerol transfer protein (PG/PI-TP). The cDNA encodes a 173 amino acid protein of 18823 Da. The deduced amino acid sequence from position 38 to 67 is 100% identical to the N-terminal sequence (first 30 amino acids) of the purified PG/PI-TP. This amino acid sequence is preceded by a leader peptide of 37 amino acids which is predicted to be composed of a signal peptide of 21 amino acids followed by an extra-sequence of 16 amino acids, or a membrane anchor protein signal (amino acid 5-29). This strongly suggests that the PG/PI-TP is a targeted protein. The deduced mature protein is 138 amino acids long with a predicted molecular mass of 14933 Da. Comparison of the deduced PG/PI-TP sequence with other polypeptide sequences available in databases revealed a homology with a protein deduced from an open reading frame coding for an unknown protein in Saccharomyces cerevisiae (36% identity and 57% similarity). Apart from this homology, the PG/PI-TP is unique and specific to the filamentous fungi on the basis of comparison of PLTP protein sequences. Northern blot analysis of RNA isolated from A. oryzae cultures grown on glucose or glucose supplemented with phospholipids suggests that the PG/PI-TP is transcribed by only one RNA species and allows us to show that expression of the protein is regulated at the messenger RNA level.  (+info)

High-linoleate and high-alpha-linolenate diets affect learning ability and natural behavior in SAMR1 mice. (2/11419)

Semipurified diets incorporating either perilla oil [high in alpha-linolenate, 18:3(n-3)] or safflower oil [high in linoleate, 18:2(n-6)] were fed to senescence-resistant SAMR1 mouse dams and their pups. Male offspring at 15 mo were examined using behavioral tests. In the open field test, locomotor activity during a 5-min period was significantly higher in the safflower oil group than in the perilla oil group. Observations of the circadian rhythm (48 h) of spontaneous motor activity indicated that the safflower oil group was more active than the perilla oil group during the first and second dark periods. The total number of responses to positive and negative stimuli was higher in the safflower oil group than in the perilla oil group in the light and dark discrimination learning test, but the correct response ratio was lower in the safflower oil group. The difference in the (n-6)/(n-3) ratios of the diets reflected the proportions of (n-6) polyunsaturated fatty acids, rather than those of (n-3) polyunsaturated fatty acids in the brain total fatty acids, and in the proportions of (n-6) and (n-3) polyunsaturated fatty acids in the total polyunsaturated fatty acids of the brain phospholipids. These results suggest that in SAMR1 mice, the dietary alpha-linolenate/linoleate balance affects the (n-6)/(n-3) ratio of brain phospholipids, and this may modify emotional reactivity and learning ability.  (+info)

Relocating the active site of activated protein C eliminates the need for its protein S cofactor. A fluorescence resonance energy transfer study. (3/11419)

The effect of replacing the gamma-carboxyglutamic acid domain of activated protein C (APC) with that of prothrombin on the topography of the membrane-bound enzyme was examined using fluorescence resonance energy transfer. The average distance of closest approach (assuming kappa2 = 2/3) between a fluorescein in the active site of the chimera and octadecylrhodamine at the membrane surface was 89 A, compared with 94 A for wild-type APC. The gamma-carboxyglutamic acid domain substitution therefore lowered and/or reoriented the active site, repositioning it close to the 84 A observed for the APC. protein S complex. Protein S enhances wild-type APC cleavage of factor Va at Arg306, but the inactivation rate of factor Va Leiden by the chimera alone is essentially equal to that by wild-type APC plus protein S. These data suggest that the activities of the chimera and of the APC.protein S complex are equivalent because the active site of the chimeric protein is already positioned near the optimal location above the membrane surface to cleave Arg306. Thus, one mechanism by which protein S regulates APC activity is by relocating its active site to the proper position above the membrane surface to optimize factor Va cleavage.  (+info)

Dietary control of triglyceride and phospholipid synthesis in rat liver slices. (4/11419)

1. The effect of dietary manipulation on the synthesis of triglycerides and phospholipids was investigated by determining the incorporation of labeled long-chain fatty acid or glycerol into these lipids in liver slices derived from normally fed, fasted, and fat-free refed rats. 2. Triglyceride synthesis was affected markedly by the dietary regime of the animal; the lowest rates were measured with fasted rats, and the highest ones with fat-free refed rats. 3. In contrast to triglyceride synthesis, phospholipid synthesis occured at virtually constant rates regardless of the dietary conditions. 4. Addition of large amounts of fatty acid to the incubation mixture resulted in a marked stimulation of triglyceride synthesis, whereas phospholipid synthesis was affected to a much smaller extent. 5. These results indicate that the synthesis of triglycerides and that of phospholipids are controlled independently, and that the availability of fatty acid in the cell contributes to the control of triglyceride synthesis.  (+info)

Efficient binding of regulated secretory protein aggregates to membrane phospholipids at acidic pH. (5/11419)

Some regulated secretory proteins are thought to be targeted to secretory granules through an acidic-dependent aggregation in the trans-Golgi network. In this report we use pancreatic zymogens, a paradigm of regulated proteins, to test this hypothesis, because they qualitatively aggregate upon acidification in vitro. Pig zymogens were found to start to aggregate significantly at pH approximately 6.0, a pH slightly lower than that at which rat zymogens aggregate, but still compatible with the pH of the cell-sorting compartments. When pig zymogen granule membranes were mixed with the zymogens in the aggregation assay, membranes that normally floated on 1 M sucrose were observed to be pelleted by the aggregating zymogens. Rat membranes were pelleted by pig zymogens and vice versa. Igs, typical constitutively secreted proteins, which needed chemical cross-linking to serve as an aggregated protein control, pelleted membranes almost independently of pH. Corresponding cross-linked zymogen-binding ability and pH dependence was unaffected by the chemical modification. Membranes treated with sodium carbonate, pH 11, or with protease K, were still pelleted by zymogens, suggesting that the aggregated zymogens bound to membrane lipids. This hypothesis was confirmed by the efficient pelleting of unilamellar vesicles composed of granule membrane lipids. Vesicles composed of single classes of phospholipids were also pelleted, but with various efficacies. We conclude that pancreatic zymogen aggregates, formed under the acidic conditions of the secretory pathway sorting compartments, have the capacity to bind firmly to membranes through their phospholipid constituents.  (+info)

The Npc1 mutation causes an altered expression of caveolin-1, annexin II and protein kinases and phosphorylation of caveolin-1 and annexin II in murine livers. (6/11419)

We have previously demonstrated (1) an increased expression of caveolin-1 in murine heterozygous and homozygous Niemann-Pick type C (NPC) livers, and (2) an increased concentration of unesterified cholesterol in a detergent insoluble caveolae-enriched fraction from homozygous livers. To define further the relationship between caveolin-1 function and the cholesterol trafficking defect in NPC, we examined the expression and distribution of additional caveolar and signal transduction proteins. The expression of annexin II was significantly increased in homozygous liver homogenates and the Triton X-100 insoluble floating fraction (TIFF). Phosphoamino acid analysis of caveolin-1 and annexin II from the homozygous TIFF demonstrated an increase in serine and tyrosine phosphorylation, respectively. To determine the basis for increased phosphorylation of these proteins, the expression and distribution of several protein kinases was examined. The expression of PKCalpha, PKCzeta and pp60-src (protein kinases) were significantly increased in both heterozygous and homozygous liver homogenates, while PKCdelta was increased only in homozygous livers. Of the protein kinases analyzed, only CK IIalpha was significantly enriched in the heterozygous TIFF. Finally, the concentration of diacylglycerol in the homozygous TIFF was significantly increased and this elevation may modulate PKC distribution and function. These results provide additional evidence for involvement of a caveolin-1 containing cellular fraction in the pathophysiology of NPC and also suggest that the Npc1 gene product may directly or indirectly, regulate the expression and distribution of signaling molecules.  (+info)

Redundant systems of phosphatidic acid biosynthesis via acylation of glycerol-3-phosphate or dihydroxyacetone phosphate in the yeast Saccharomyces cerevisiae. (7/11419)

In the yeast Saccharomyces cerevisiae lipid particles harbor two acyltransferases, Gat1p and Slc1p, which catalyze subsequent steps of acylation required for the formation of phosphatidic acid. Both enzymes are also components of the endoplasmic reticulum, but this compartment contains additional acyltransferase(s) involved in the biosynthesis of phosphatidic acid (K. Athenstaedt and G. Daum, J. Bacteriol. 179:7611-7616, 1997). Using the gat1 mutant strain TTA1, we show here that Gat1p present in both subcellular fractions accepts glycerol-3-phosphate and dihydroxyacetone phosphate as a substrate. Similarly, the additional acyltransferase(s) present in the endoplasmic reticulum can acylate both precursors. In contrast, yeast mitochondria harbor an enzyme(s) that significantly prefers dihydroxyacetone phosphate as a substrate for acylation, suggesting that at least one additional independent acyltransferase is present in this organelle. Surprisingly, enzymatic activity of 1-acyldihydroxyacetone phosphate reductase, which is required for the conversion of 1-acyldihydroxyacetone phosphate to 1-acylglycerol-3-phosphate (lysophosphatidic acid), is detectable only in lipid particles and the endoplasmic reticulum and not in mitochondria. In vivo labeling of wild-type cells with [2-3H, U-14C]glycerol revealed that both glycerol-3-phosphate and dihydroxyacetone phosphate can be incorporated as a backbone of glycerolipids. In the gat1 mutant and the 1-acylglycerol-3-phosphate acyltransferase slc1 mutant, the dihydroxyacetone phosphate pathway of phosphatidic acid biosynthesis is slightly preferred as compared to the wild type. Thus, mutations of the major acyltransferases Gat1p and Slc1p lead to an increased contribution of mitochondrial acyltransferase(s) to glycerolipid synthesis due to their substrate preference for dihydroxyacetone phosphate.  (+info)

Platelet high affinity low density lipoprotein binding and import of lipoprotein derived phospholipids. (8/11419)

The binding of low density lipoprotein (LDL) to the platelet cell membrane could facilitate the transfer of phospholipids from LDL to the platelets. A polyclonal antibody against the platelet glycoproteins IIb/IIIa inhibited the high affinity binding of 125I-LDL by up to 80%. The transfer of pyrene (py)-labeled sphingomyelin (SM), phosphatidylcholine and phosphatidylethanolamine from LDL to the platelets was unaffected by the antibody. The lectin wheat germ agglutinin (WGA) reduced the binding of 125I-LDL to the platelets by approximately 80%. In contrast, the lectin stimulated the transfer of SM from LDL into the platelets by about three-fold. WGA also specifically augmented the transfer of py-SM between lipid vesicles and the platelets, the stimulation being abolished in the presence of N-acetylglucosamine. Dextran sulfate (DS) increased the specific binding of 125I-LDL to the platelets by up to 2.8-fold. On the other hand, the import of LDL-derived py-phospholipids was unaffected by DS. Together, the results indicate that the phospholipid transfer from LDL to the platelets is independent of the high affinity LDL binding to the platelets and is specifically stimulated by WGA. Thus, the interactions of platelets with LDL phospholipids differ markedly from those with the apoprotein components of the lipoproteins.  (+info)

Phospholipids are a major class of lipids that consist of a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails. The head is composed of a phosphate group, which is often bound to an organic molecule such as choline, ethanolamine, serine or inositol. The tails are made up of two fatty acid chains.

Phospholipids are a key component of cell membranes and play a crucial role in maintaining the structural integrity and function of the cell. They form a lipid bilayer, with the hydrophilic heads facing outwards and the hydrophobic tails facing inwards, creating a barrier that separates the interior of the cell from the outside environment.

Phospholipids are also involved in various cellular processes such as signal transduction, intracellular trafficking, and protein function regulation. Additionally, they serve as emulsifiers in the digestive system, helping to break down fats in the diet.

Phosphatidylcholines (PtdCho) are a type of phospholipids that are essential components of cell membranes in living organisms. They are composed of a hydrophilic head group, which contains a choline moiety, and two hydrophobic fatty acid chains. Phosphatidylcholines are crucial for maintaining the structural integrity and function of cell membranes, and they also serve as important precursors for the synthesis of signaling molecules such as acetylcholine. They can be found in various tissues and biological fluids, including blood, and are abundant in foods such as soybeans, eggs, and meat. Phosphatidylcholines have been studied for their potential health benefits, including their role in maintaining healthy lipid metabolism and reducing the risk of cardiovascular disease.

Phospholipid transfer proteins (PLTPs) are a group of proteins found in the bloodstream that play a crucial role in the distribution and metabolism of phospholipids, which are key components of cell membranes. These proteins facilitate the transfer of phospholipids between different lipoprotein particles, such as high-density lipoproteins (HDL) and low-density lipoproteins (LDL), in a process known as non-vesicular lipid transport.

PLTPs can also modulate the size, composition, and function of these lipoprotein particles, which has implications for lipid metabolism, inflammation, and atherosclerosis. Additionally, PLTPs have been implicated in various physiological processes, including cell signaling, membrane trafficking, and host defense mechanisms.

It is worth noting that while PLTPs are important regulators of lipid metabolism, their precise role in human health and disease is still an area of active research.

Phosphatidylethanolamines (PE) are a type of phospholipid that are abundantly found in the cell membranes of living organisms. They play a crucial role in maintaining the structural integrity and functionality of the cell membrane. PE contains a hydrophilic head, which consists of an ethanolamine group linked to a phosphate group, and two hydrophobic fatty acid chains. This unique structure allows PE to form a lipid bilayer, where the hydrophilic heads face outwards and interact with the aqueous environment, while the hydrophobic tails face inwards and interact with each other.

PE is also involved in various cellular processes, such as membrane trafficking, autophagy, and signal transduction. Additionally, PE can be modified by the addition of various functional groups or molecules, which can further regulate its functions and interactions within the cell. Overall, phosphatidylethanolamines are essential components of cellular membranes and play a critical role in maintaining cellular homeostasis.

Membrane lipids are the main component of biological membranes, forming a lipid bilayer in which various cellular processes take place. These lipids include phospholipids, glycolipids, and cholesterol. Phospholipids are the most abundant type, consisting of a hydrophilic head (containing a phosphate group) and two hydrophobic tails (composed of fatty acid chains). Glycolipids contain a sugar group attached to the lipid molecule. Cholesterol helps regulate membrane fluidity and permeability. Together, these lipids create a selectively permeable barrier that separates cells from their environment and organelles within cells.

Phospholipid ethers are a type of phospholipid in which the traditional fatty acid chains are replaced by alkyl or alkenyl groups linked to the glycerol backbone via an ether bond. They are a significant component of lipoproteins and cell membranes, particularly in archaea, where they contribute to the stability and rigidity of the membrane at extreme temperatures and pressures.

The two main types of phospholipid ethers are plasmalogens and diether lipids. Plasmalogens contain a vinyl ether bond at the sn-1 position, while diether lipids have an ether bond at both the sn-1 and sn-2 positions. These unique structures give phospholipid ethers distinct chemical and biological properties compared to conventional phospholipids with ester-linked fatty acids.

Phosphatidylserines are a type of phospholipids that are essential components of the cell membrane, particularly in the brain. They play a crucial role in maintaining the fluidity and permeability of the cell membrane, and are involved in various cellular processes such as signal transduction, protein anchorage, and apoptosis (programmed cell death). Phosphatidylserines contain a polar head group made up of serine amino acids and two non-polar fatty acid tails. They are abundant in the inner layer of the cell membrane but can be externalized to the outer layer during apoptosis, where they serve as signals for recognition and removal of dying cells by the immune system. Phosphatidylserines have been studied for their potential benefits in various medical conditions, including cognitive decline, Alzheimer's disease, and depression.

Liposomes are artificially prepared, small, spherical vesicles composed of one or more lipid bilayers that enclose an aqueous compartment. They can encapsulate both hydrophilic and hydrophobic drugs, making them useful for drug delivery applications in the medical field. The lipid bilayer structure of liposomes is similar to that of biological membranes, which allows them to merge with and deliver their contents into cells. This property makes liposomes a valuable tool in delivering drugs directly to targeted sites within the body, improving drug efficacy while minimizing side effects.

A lipid bilayer is a thin membrane made up of two layers of lipid molecules, primarily phospholipids. The hydrophilic (water-loving) heads of the lipids face outwards, coming into contact with watery environments on both sides, while the hydrophobic (water-fearing) tails point inward, away from the aqueous surroundings. This unique structure allows lipid bilayers to form a stable barrier that controls the movement of molecules and ions in and out of cells and organelles, thus playing a crucial role in maintaining cellular compartmentalization and homeostasis.

Phosphatidylglycerols are a type of glycerophospholipids, which are major components of biological membranes. They are composed of a glycerol backbone to which two fatty acid chains and a phosphate group are attached. In the case of phosphatidylglycerols, the phosphate group is linked to a glycerol molecule through an ester bond, forming a phosphoglyceride.

Phosphatidylglycerols are unique because they have an additional glycerol molecule attached to the phosphate group, making them more complex than other glycerophospholipids such as phosphatidylcholine or phosphatidylethanolamine. This additional glycerol moiety can be further modified by the addition of various headgroups, leading to the formation of different subclasses of phosphatidylglycerols.

In biological membranes, phosphatidylglycerols are often found in the inner leaflet of the mitochondrial membrane and play important roles in maintaining the structure and function of this organelle. They have also been implicated in various cellular processes such as membrane fusion, protein trafficking, and bacterial cell wall biosynthesis.

Fatty acids are carboxylic acids with a long aliphatic chain, which are important components of lipids and are widely distributed in living organisms. They can be classified based on the length of their carbon chain, saturation level (presence or absence of double bonds), and other structural features.

The two main types of fatty acids are:

1. Saturated fatty acids: These have no double bonds in their carbon chain and are typically solid at room temperature. Examples include palmitic acid (C16:0) and stearic acid (C18:0).
2. Unsaturated fatty acids: These contain one or more double bonds in their carbon chain and can be further classified into monounsaturated (one double bond) and polyunsaturated (two or more double bonds) fatty acids. Examples of unsaturated fatty acids include oleic acid (C18:1, monounsaturated), linoleic acid (C18:2, polyunsaturated), and alpha-linolenic acid (C18:3, polyunsaturated).

Fatty acids play crucial roles in various biological processes, such as energy storage, membrane structure, and cell signaling. Some essential fatty acids cannot be synthesized by the human body and must be obtained through dietary sources.

Cardiolipins are a type of phospholipid that are primarily found in the inner mitochondrial membrane of cells. They play a crucial role in several important cellular processes, including energy production, apoptosis (programmed cell death), and maintenance of the structural integrity of the mitochondria.

Cardiolipins are unique because they contain four fatty acid chains, whereas most other phospholipids contain only two. This gives cardiolipins a distinctive conical shape that is important for their function in maintaining the curvature and stability of the inner mitochondrial membrane.

Cardiolipins have also been implicated in various diseases, including neurodegenerative disorders, cancer, and bacterial infections. For example, changes in cardiolipin composition or distribution have been linked to mitochondrial dysfunction in Parkinson's disease and other neurological conditions. Additionally, certain bacteria, such as Neisseria gonorrhoeae and Chlamydia trachomatis, can manipulate host cell cardiolipins to facilitate their own survival and replication.

In summary, cardiolipins are essential phospholipids found in the inner mitochondrial membrane that play a critical role in several cellular processes, and have been implicated in various diseases.

Phosphatidylinositols (PIs) are a type of phospholipid that are abundant in the cell membrane. They contain a glycerol backbone, two fatty acid chains, and a head group consisting of myo-inositol, a cyclic sugar molecule, linked to a phosphate group.

Phosphatidylinositols can be phosphorylated at one or more of the hydroxyl groups on the inositol ring, forming various phosphoinositides (PtdInsPs) with different functions. These signaling molecules play crucial roles in regulating cellular processes such as membrane trafficking, cytoskeletal organization, and signal transduction pathways that control cell growth, differentiation, and survival.

Phosphatidylinositol 4,5-bisphosphate (PIP2) is a prominent phosphoinositide involved in the regulation of ion channels, enzymes, and cytoskeletal proteins. Upon activation of certain receptors, PIP2 can be cleaved by the enzyme phospholipase C into diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (InsP3), which act as second messengers to trigger downstream signaling events.

Thin-layer chromatography (TLC) is a type of chromatography used to separate, identify, and quantify the components of a mixture. In TLC, the sample is applied as a small spot onto a thin layer of adsorbent material, such as silica gel or alumina, which is coated on a flat, rigid support like a glass plate. The plate is then placed in a developing chamber containing a mobile phase, typically a mixture of solvents.

As the mobile phase moves up the plate by capillary action, it interacts with the stationary phase and the components of the sample. Different components of the mixture travel at different rates due to their varying interactions with the stationary and mobile phases, resulting in distinct spots on the plate. The distance each component travels can be measured and compared to known standards to identify and quantify the components of the mixture.

TLC is a simple, rapid, and cost-effective technique that is widely used in various fields, including forensics, pharmaceuticals, and research laboratories. It allows for the separation and analysis of complex mixtures with high resolution and sensitivity, making it an essential tool in many analytical applications.

Phospholipases are a group of enzymes that catalyze the hydrolysis of phospholipids, which are major components of cell membranes. Phospholipases cleave specific ester bonds in phospholipids, releasing free fatty acids and other lipophilic molecules. Based on the site of action, phospholipases are classified into four types:

1. Phospholipase A1 (PLA1): This enzyme hydrolyzes the ester bond at the sn-1 position of a glycerophospholipid, releasing a free fatty acid and a lysophospholipid.
2. Phospholipase A2 (PLA2): PLA2 cleaves the ester bond at the sn-2 position of a glycerophospholipid, releasing a free fatty acid (often arachidonic acid) and a lysophospholipid. Arachidonic acid is a precursor for eicosanoids, which are signaling molecules involved in inflammation and other physiological processes.
3. Phospholipase C (PLC): PLC hydrolyzes the phosphodiester bond in the headgroup of a glycerophospholipid, releasing diacylglycerol (DAG) and a soluble head group, such as inositol trisphosphate (IP3). DAG acts as a secondary messenger in intracellular signaling pathways, while IP3 mediates the release of calcium ions from intracellular stores.
4. Phospholipase D (PLD): PLD cleaves the phosphoester bond between the headgroup and the glycerol moiety of a glycerophospholipid, releasing phosphatidic acid (PA) and a free head group. PA is an important signaling molecule involved in various cellular processes, including membrane trafficking, cytoskeletal reorganization, and cell survival.

Phospholipases have diverse roles in normal physiology and pathophysiological conditions, such as inflammation, immunity, and neurotransmission. Dysregulation of phospholipase activity can contribute to the development of various diseases, including cancer, cardiovascular disease, and neurological disorders.

A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.

Cholesterol is a type of lipid (fat) molecule that is an essential component of cell membranes and is also used to make certain hormones and vitamins in the body. It is produced by the liver and is also obtained from animal-derived foods such as meat, dairy products, and eggs.

Cholesterol does not mix with blood, so it is transported through the bloodstream by lipoproteins, which are particles made up of both lipids and proteins. There are two main types of lipoproteins that carry cholesterol: low-density lipoproteins (LDL), also known as "bad" cholesterol, and high-density lipoproteins (HDL), also known as "good" cholesterol.

High levels of LDL cholesterol in the blood can lead to a buildup of cholesterol in the walls of the arteries, increasing the risk of heart disease and stroke. On the other hand, high levels of HDL cholesterol are associated with a lower risk of these conditions because HDL helps remove LDL cholesterol from the bloodstream and transport it back to the liver for disposal.

It is important to maintain healthy levels of cholesterol through a balanced diet, regular exercise, and sometimes medication if necessary. Regular screening is also recommended to monitor cholesterol levels and prevent health complications.

Sphingomyelins are a type of sphingolipids, which are a class of lipids that contain sphingosine as a backbone. Sphingomyelins are composed of phosphocholine or phosphoethanolamine bound to the ceramide portion of the molecule through a phosphodiester linkage. They are important components of cell membranes, particularly in the myelin sheath that surrounds nerve fibers. Sphingomyelins can be hydrolyzed by the enzyme sphingomyelinase to form ceramide and phosphorylcholine or phosphorylethanolamine. Abnormalities in sphingomyelin metabolism have been implicated in several diseases, including Niemann-Pick disease, a group of inherited lipid storage disorders.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Phospholipases A are a group of enzymes that hydrolyze phospholipids into fatty acids and lysophospholipids by cleaving the ester bond at the sn-1 or sn-2 position of the glycerol backbone. There are three main types of Phospholipases A:

* Phospholipase A1 (PLA1): This enzyme specifically hydrolyzes the ester bond at the sn-1 position, releasing a free fatty acid and a lysophospholipid.
* Phospholipase A2 (PLA2): This enzyme specifically hydrolyzes the ester bond at the sn-2 position, releasing a free fatty acid (often arachidonic acid, which is a precursor for eicosanoids) and a lysophospholipid.
* Phospholipase A/B (PLA/B): This enzyme has both PLA1 and PLA2 activity and can hydrolyze the ester bond at either the sn-1 or sn-2 position.

Phospholipases A play important roles in various biological processes, including cell signaling, membrane remodeling, and host defense. They are also involved in several diseases, such as atherosclerosis, neurodegenerative disorders, and cancer.

1,2-Dipalmitoylphosphatidylcholine (DPPC) is a type of phospholipid molecule that is a major component of the lipid bilayer in biological membranes, particularly in lung surfactant. It is composed of two palmitic acid chains attached to a glycerol backbone, which is linked to a phosphate group and a choline headgroup. The chemical formula for DPPC is C44H86NO8P.

In the body, DPPC plays an important role in maintaining the structure and function of cell membranes, as well as reducing surface tension in the lungs. It is also used in research and medical settings as a component of liposomes, which are used for drug delivery and other biomedical applications.

Phospholipase A2 (PLA2) is a type of enzyme that catalyzes the hydrolysis of the sn-2 ester bond in glycerophospholipids, releasing free fatty acids, such as arachidonic acid, and lysophospholipids. These products are important precursors for the biosynthesis of various signaling molecules, including eicosanoids, platelet-activating factor (PAF), and lipoxins, which play crucial roles in inflammation, immunity, and other cellular processes.

Phospholipases A2 are classified into several groups based on their structure, mechanism of action, and cellular localization. The secreted PLA2s (sPLA2s) are found in extracellular fluids and are characterized by a low molecular weight, while the calcium-dependent cytosolic PLA2s (cPLA2s) are larger proteins that reside within cells.

Abnormal regulation or activity of Phospholipase A2 has been implicated in various pathological conditions, such as inflammation, neurodegenerative diseases, and cancer. Therefore, understanding the biology and function of these enzymes is essential for developing novel therapeutic strategies to target these disorders.

Lipids are a broad group of organic compounds that are insoluble in water but soluble in nonpolar organic solvents. They include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, and phospholipids. Lipids serve many important functions in the body, including energy storage, acting as structural components of cell membranes, and serving as signaling molecules. High levels of certain lipids, particularly cholesterol and triglycerides, in the blood are associated with an increased risk of cardiovascular disease.

Phosphatidic acids (PAs) are a type of phospholipid that are essential components of cell membranes. They are composed of a glycerol backbone linked to two fatty acid chains and a phosphate group. The phosphate group is esterified to another molecule, usually either serine, inositol, or choline, forming different types of phosphatidic acids.

PAs are particularly important as they serve as key regulators of many cellular processes, including signal transduction, membrane trafficking, and autophagy. They can act as signaling molecules by binding to and activating specific proteins, such as the enzyme phospholipase D, which generates second messengers involved in various signaling pathways.

PAs are also important intermediates in the synthesis of other phospholipids, such as phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol. They are produced by the enzyme diacylglycerol kinase (DGK), which adds a phosphate group to diacylglycerol (DAG) to form PA.

Abnormal levels of PAs have been implicated in various diseases, including cancer, diabetes, and neurological disorders. Therefore, understanding the regulation and function of PAs is an active area of research with potential therapeutic implications.

Dimyristoylphosphatidylcholine (DMPC) is a type of phospholipid molecule that is commonly found in animal cell membranes. It is composed of two myristoyl fatty acid chains, a phosphate group, and a choline headgroup. DMPC has a gel-to-liquid crystalline phase transition temperature of around 23-25°C, which makes it a useful compound for studying the physical properties of lipid membranes and for creating model membrane systems in laboratory experiments.

Artificial membranes are synthetic or man-made materials that possess properties similar to natural biological membranes, such as selective permeability and barrier functions. These membranes can be designed to control the movement of molecules, ions, or cells across them, making them useful in various medical and biotechnological applications.

Examples of artificial membranes include:

1. Dialysis membranes: Used in hemodialysis for patients with renal failure, these semi-permeable membranes filter waste products and excess fluids from the blood while retaining essential proteins and cells.
2. Hemofiltration membranes: Utilized in extracorporeal circuits to remove larger molecules, such as cytokines or inflammatory mediators, from the blood during critical illnesses or sepsis.
3. Drug delivery systems: Artificial membranes can be used to encapsulate drugs, allowing for controlled release and targeted drug delivery in specific tissues or cells.
4. Tissue engineering: Synthetic membranes serve as scaffolds for cell growth and tissue regeneration, guiding the formation of new functional tissues.
5. Biosensors: Artificial membranes can be integrated into biosensing devices to selectively detect and quantify biomolecules, such as proteins or nucleic acids, in diagnostic applications.
6. Microfluidics: Artificial membranes are used in microfluidic systems for lab-on-a-chip applications, enabling the manipulation and analysis of small volumes of fluids for various medical and biological purposes.

Lysophosphatidylcholines (LPCs) are a type of glycerophospholipids, which are major components of cell membranes. They are formed by the hydrolysis of phosphatidylcholines, another type of glycerophospholipids, catalyzed by the enzyme phospholipase A2. LPCs contain a single fatty acid chain attached to a glycerol backbone and a choline headgroup.

In medical terms, LPCs have been implicated in various physiological and pathological processes, such as cell signaling, membrane remodeling, and inflammation. Elevated levels of LPCs have been found in several diseases, including cardiovascular disease, neurodegenerative disorders, and cancer. They can also serve as biomarkers for the diagnosis and prognosis of these conditions.

Unsaturated fatty acids are a type of fatty acid that contain one or more double bonds in their carbon chain. These double bonds can be either cis or trans configurations, although the cis configuration is more common in nature. The presence of these double bonds makes unsaturated fatty acids more liquid at room temperature and less prone to spoilage than saturated fatty acids, which do not have any double bonds.

Unsaturated fatty acids can be further classified into two main categories: monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs). MUFAs contain one double bond in their carbon chain, while PUFAs contain two or more.

Examples of unsaturated fatty acids include oleic acid (a MUFA found in olive oil), linoleic acid (a PUFA found in vegetable oils), and alpha-linolenic acid (an omega-3 PUFA found in flaxseed and fish). Unsaturated fatty acids are essential nutrients for the human body, as they play important roles in various physiological processes such as membrane structure, inflammation, and blood clotting. It is recommended to consume a balanced diet that includes both MUFAs and PUFAs to maintain good health.

Choline is an essential nutrient that is vital for the normal functioning of all cells, particularly those in the brain and liver. It is a water-soluble compound that is neither a vitamin nor a mineral, but is often grouped with vitamins because it has many similar functions. Choline is a precursor to the neurotransmitter acetylcholine, which plays an important role in memory, mood, and other cognitive processes. It also helps to maintain the structural integrity of cell membranes and is involved in the transport and metabolism of fats.

Choline can be synthesized by the body in small amounts, but it is also found in a variety of foods such as eggs, meat, fish, nuts, and cruciferous vegetables. Some people may require additional choline through supplementation, particularly if they follow a vegetarian or vegan diet, are pregnant or breastfeeding, or have certain medical conditions that affect choline metabolism.

Deficiency in choline can lead to a variety of health problems, including liver disease, muscle damage, and neurological disorders. On the other hand, excessive intake of choline can cause fishy body odor, sweating, and gastrointestinal symptoms such as diarrhea and vomiting. It is important to maintain adequate levels of choline through a balanced diet and, if necessary, supplementation under the guidance of a healthcare professional.

Plasmalogens are a type of complex lipid called glycerophospholipids, which are essential components of cell membranes. They are characterized by having a unique chemical structure that includes a vinyl ether bond at the sn-1 position of the glycerol backbone and an ester bond at the sn-2 position, with the majority of them containing polyunsaturated fatty acids. The headgroup attached to the sn-3 position is typically choline or ethanolamine.

Plasmalogens are abundant in certain tissues, such as the brain, heart, and skeletal muscle. They have been suggested to play important roles in cellular functions, including membrane fluidity, signal transduction, and protection against oxidative stress. Reduced levels of plasmalogens have been associated with various diseases, including neurological disorders, cardiovascular diseases, and aging-related conditions.

Lipid metabolism is the process by which the body breaks down and utilizes lipids (fats) for various functions, such as energy production, cell membrane formation, and hormone synthesis. This complex process involves several enzymes and pathways that regulate the digestion, absorption, transport, storage, and consumption of fats in the body.

The main types of lipids involved in metabolism include triglycerides, cholesterol, phospholipids, and fatty acids. The breakdown of these lipids begins in the digestive system, where enzymes called lipases break down dietary fats into smaller molecules called fatty acids and glycerol. These molecules are then absorbed into the bloodstream and transported to the liver, which is the main site of lipid metabolism.

In the liver, fatty acids may be further broken down for energy production or used to synthesize new lipids. Excess fatty acids may be stored as triglycerides in specialized cells called adipocytes (fat cells) for later use. Cholesterol is also metabolized in the liver, where it may be used to synthesize bile acids, steroid hormones, and other important molecules.

Disorders of lipid metabolism can lead to a range of health problems, including obesity, diabetes, cardiovascular disease, and non-alcoholic fatty liver disease (NAFLD). These conditions may be caused by genetic factors, lifestyle habits, or a combination of both. Proper diagnosis and management of lipid metabolism disorders typically involves a combination of dietary changes, exercise, and medication.

Pulmonary surfactants are a complex mixture of lipids and proteins that are produced by the alveolar type II cells in the lungs. They play a crucial role in reducing the surface tension at the air-liquid interface within the alveoli, which helps to prevent collapse of the lungs during expiration. Surfactants also have important immunological functions, such as inhibiting the growth of certain bacteria and modulating the immune response. Deficiency or dysfunction of pulmonary surfactants can lead to respiratory distress syndrome (RDS) in premature infants and other lung diseases.

Membrane fluidity, in the context of cell biology, refers to the ability of the phospholipid bilayer that makes up the cell membrane to change its structure and organization in response to various factors. The membrane is not a static structure but rather a dynamic one, with its lipids constantly moving and changing position.

Membrane fluidity is determined by the fatty acid composition of the phospholipids that make up the bilayer. Lipids with unsaturated fatty acids have kinks in their hydrocarbon chains, which prevent them from packing closely together and increase membrane fluidity. In contrast, lipids with saturated fatty acids can pack closely together, reducing membrane fluidity.

Membrane fluidity is important for various cellular processes, including the movement of proteins within the membrane, the fusion of vesicles with the membrane during exocytosis and endocytosis, and the ability of the membrane to respond to changes in temperature and other environmental factors. Abnormalities in membrane fluidity have been linked to various diseases, including cancer, neurological disorders, and infectious diseases.

Inositol is not considered a true "vitamin" because it can be created by the body from glucose. However, it is an important nutrient and is sometimes referred to as vitamin B8. It is a type of sugar alcohol that is found in both animals and plants. Inositol is involved in various biological processes, including:

1. Signal transduction: Inositol phospholipids are key components of cell membranes and play a crucial role in intracellular signaling pathways. They act as secondary messengers in response to hormones, neurotransmitters, and growth factors.
2. Insulin sensitivity: Inositol and its derivatives, such as myo-inositol and D-chiro-inositol, are involved in insulin signal transduction. Abnormalities in inositol metabolism have been linked to insulin resistance and conditions like polycystic ovary syndrome (PCOS).
3. Cerebral and ocular functions: Inositol is essential for the proper functioning of neurons and has been implicated in various neurological and psychiatric disorders, such as depression, anxiety, and bipolar disorder. It also plays a role in maintaining eye health.
4. Lipid metabolism: Inositol participates in the breakdown and transport of fats within the body.
5. Gene expression: Inositol and its derivatives are involved in regulating gene expression through epigenetic modifications.

Inositol can be found in various foods, including fruits, beans, grains, nuts, and vegetables. It is also available as a dietary supplement for those who wish to increase their intake.

Micelles are structures formed in a solution when certain substances, such as surfactants, reach a critical concentration called the critical micelle concentration (CMC). At this concentration, these molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) components, arrange themselves in a spherical shape with the hydrophilic parts facing outward and the hydrophobic parts clustered inside. This formation allows the hydrophobic components to avoid contact with water while the hydrophilic components interact with it. Micelles are important in various biological and industrial processes, such as drug delivery, soil remediation, and the formation of emulsions.

Arachidonic acid is a type of polyunsaturated fatty acid that is found naturally in the body and in certain foods. It is an essential fatty acid, meaning that it cannot be produced by the human body and must be obtained through the diet. Arachidonic acid is a key component of cell membranes and plays a role in various physiological processes, including inflammation and blood clotting.

In the body, arachidonic acid is released from cell membranes in response to various stimuli, such as injury or infection. Once released, it can be converted into a variety of bioactive compounds, including prostaglandins, thromboxanes, and leukotrienes, which mediate various physiological responses, including inflammation, pain, fever, and blood clotting.

Arachidonic acid is found in high concentrations in animal products such as meat, poultry, fish, and eggs, as well as in some plant sources such as certain nuts and seeds. It is also available as a dietary supplement. However, it is important to note that excessive intake of arachidonic acid can contribute to the development of inflammation and other health problems, so it is recommended to consume this fatty acid in moderation as part of a balanced diet.

Glycerylphosphorylcholine (GPC) is not typically considered a medical term, but it is a choline-containing phospholipid that can be found in various tissues and fluids within the human body. It is also available as a dietary supplement. Here's a definition of Glycerylphosphorylcholine:

Glycerylphosphorylcholine (GPC) is a natural choline-containing compound that is present in various tissues and fluids within the human body, including neural tissue, muscle, and blood. It plays an essential role in the synthesis of the neurotransmitter acetylcholine, which is involved in memory, learning, and other cognitive functions. GPC can also be found in some foods, such as egg yolks and soybeans, and is available as a dietary supplement. In the body, GPC can be converted to phosphatidylcholine, another important phospholipid that is necessary for maintaining cell membrane structure and function.

Proteolipids are a type of complex lipid-containing proteins that are insoluble in water and have a high content of hydrophobic amino acids. They are primarily found in the plasma membrane of cells, where they play important roles in maintaining the structural integrity and function of the membrane. Proteolipids are also found in various organelles, including mitochondria, lysosomes, and peroxisomes.

Proteolipids are composed of a hydrophobic protein core that is tightly associated with a lipid bilayer through non-covalent interactions. The protein component of proteolipids typically contains several transmembrane domains that span the lipid bilayer, as well as hydrophilic regions that face the cytoplasm or the lumen of organelles.

Proteolipids have been implicated in various cellular processes, including signal transduction, membrane trafficking, and ion transport. They are also associated with several neurological disorders, such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. The study of proteolipids is an active area of research in biochemistry and cell biology, with potential implications for the development of new therapies for neurological disorders.

Phosphatidylethanolamine N-Methyltransferase (PEMT) is an enzyme that plays a role in the synthesis of phosphatidylcholine, a major phospholipid component of cell membranes. The enzyme catalyzes the transfer of methyl groups from S-adenosylmethionine to phosphatidylethanolamine, converting it into phosphatidylcholine in a three-step methylation process. This enzyme is found primarily in the endoplasmic reticulum and mitochondria of cells and has implications in lipid metabolism, liver function, and inflammation. Genetic variations and altered expression levels of PEMT have been associated with various diseases, including non-alcoholic fatty liver disease, cardiovascular disease, and neurological disorders.

Molecular conformation, also known as spatial arrangement or configuration, refers to the specific three-dimensional shape and orientation of atoms that make up a molecule. It describes the precise manner in which bonds between atoms are arranged around a molecular framework, taking into account factors such as bond lengths, bond angles, and torsional angles.

Conformational isomers, or conformers, are different spatial arrangements of the same molecule that can interconvert without breaking chemical bonds. These isomers may have varying energies, stability, and reactivity, which can significantly impact a molecule's biological activity and function. Understanding molecular conformation is crucial in fields such as drug design, where small changes in conformation can lead to substantial differences in how a drug interacts with its target.

Ethanolamine is an organic compound that is a primary amine and a secondary alcohol. It is a colorless, viscous liquid with an odor similar to ammonia. Ethanolamine is used in the manufacture of a wide variety of products including detergents, pharmaceuticals, polishes, inks, textiles, and plastics. In the body, ethanolamine is a component of many important molecules, such as phosphatidylethanolamine, which is a major constituent of cell membranes. It is also involved in the synthesis of neurotransmitters and hormones.

Temperature, in a medical context, is a measure of the degree of hotness or coldness of a body or environment. It is usually measured using a thermometer and reported in degrees Celsius (°C), degrees Fahrenheit (°F), or kelvin (K). In the human body, normal core temperature ranges from about 36.5-37.5°C (97.7-99.5°F) when measured rectally, and can vary slightly depending on factors such as time of day, physical activity, and menstrual cycle. Elevated body temperature is a common sign of infection or inflammation, while abnormally low body temperature can indicate hypothermia or other medical conditions.

Docosahexaenoic acid (DHA) is a type of long-chain omega-3 fatty acid that is essential for human health. It is an important structural component of the phospholipid membranes in the brain and retina, and plays a crucial role in the development and function of the nervous system. DHA is also involved in various physiological processes, including inflammation, blood pressure regulation, and immune response.

DHA is not produced in sufficient quantities by the human body and must be obtained through dietary sources or supplements. The richest dietary sources of DHA are fatty fish such as salmon, mackerel, and sardines, as well as algae and other marine organisms. DHA can also be found in fortified foods such as eggs, milk, and juice.

Deficiency in DHA has been linked to various health issues, including cognitive decline, vision problems, and cardiovascular disease. Therefore, it is recommended that individuals consume adequate amounts of DHA through diet or supplementation to maintain optimal health.

Membrane proteins are a type of protein that are embedded in the lipid bilayer of biological membranes, such as the plasma membrane of cells or the inner membrane of mitochondria. These proteins play crucial roles in various cellular processes, including:

1. Cell-cell recognition and signaling
2. Transport of molecules across the membrane (selective permeability)
3. Enzymatic reactions at the membrane surface
4. Energy transduction and conversion
5. Mechanosensation and signal transduction

Membrane proteins can be classified into two main categories: integral membrane proteins, which are permanently associated with the lipid bilayer, and peripheral membrane proteins, which are temporarily or loosely attached to the membrane surface. Integral membrane proteins can further be divided into three subcategories based on their topology:

1. Transmembrane proteins, which span the entire width of the lipid bilayer with one or more alpha-helices or beta-barrels.
2. Lipid-anchored proteins, which are covalently attached to lipids in the membrane via a glycosylphosphatidylinositol (GPI) anchor or other lipid modifications.
3. Monotopic proteins, which are partially embedded in the membrane and have one or more domains exposed to either side of the bilayer.

Membrane proteins are essential for maintaining cellular homeostasis and are targets for various therapeutic interventions, including drug development and gene therapy. However, their structural complexity and hydrophobicity make them challenging to study using traditional biochemical methods, requiring specialized techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and single-particle cryo-electron microscopy (cryo-EM).

Magnetic Resonance Spectroscopy (MRS) is a non-invasive diagnostic technique that provides information about the biochemical composition of tissues, including their metabolic state. It is often used in conjunction with Magnetic Resonance Imaging (MRI) to analyze various metabolites within body tissues, such as the brain, heart, liver, and muscles.

During MRS, a strong magnetic field, radio waves, and a computer are used to produce detailed images and data about the concentration of specific metabolites in the targeted tissue or organ. This technique can help detect abnormalities related to energy metabolism, neurotransmitter levels, pH balance, and other biochemical processes, which can be useful for diagnosing and monitoring various medical conditions, including cancer, neurological disorders, and metabolic diseases.

There are different types of MRS, such as Proton (^1^H) MRS, Phosphorus-31 (^31^P) MRS, and Carbon-13 (^13^C) MRS, each focusing on specific elements or metabolites within the body. The choice of MRS technique depends on the clinical question being addressed and the type of information needed for diagnosis or monitoring purposes.

Differential scanning calorimetry (DSC) is a thermoanalytical technique used to measure the difference in the amount of heat required to increase the temperature of a sample and a reference as a function of temperature. It is commonly used to study phase transitions, such as melting, crystallization, and glass transition, as well as chemical reactions, in a wide range of materials, including polymers, pharmaceuticals, and biological samples.

In DSC, the sample and reference are placed in separate pans and heated at a constant rate. The heat flow required to maintain this heating rate is continuously measured for both the sample and the reference. As the temperature of the sample changes during a phase transition or chemical reaction, the heat flow required to maintain the same heating rate will change relative to the reference. This allows for the measurement of the enthalpy change (ΔH) associated with the transition or reaction.

Differential scanning calorimetry is a powerful tool in materials science and research as it can provide information about the thermal behavior, stability, and composition of materials. It can also be used to study the kinetics of reactions and phase transitions, making it useful for optimizing processing conditions and developing new materials.

Hydrolysis is a chemical process, not a medical one. However, it is relevant to medicine and biology.

Hydrolysis is the breakdown of a chemical compound due to its reaction with water, often resulting in the formation of two or more simpler compounds. In the context of physiology and medicine, hydrolysis is a crucial process in various biological reactions, such as the digestion of food molecules like proteins, carbohydrates, and fats. Enzymes called hydrolases catalyze these hydrolysis reactions to speed up the breakdown process in the body.

An erythrocyte, also known as a red blood cell, is a type of cell that circulates in the blood and is responsible for transporting oxygen throughout the body. The erythrocyte membrane refers to the thin, flexible barrier that surrounds the erythrocyte and helps to maintain its shape and stability.

The erythrocyte membrane is composed of a lipid bilayer, which contains various proteins and carbohydrates. These components help to regulate the movement of molecules into and out of the erythrocyte, as well as provide structural support and protection for the cell.

The main lipids found in the erythrocyte membrane are phospholipids and cholesterol, which are arranged in a bilayer structure with the hydrophilic (water-loving) heads facing outward and the hydrophobic (water-fearing) tails facing inward. This arrangement helps to maintain the integrity of the membrane and prevent the leakage of cellular components.

The proteins found in the erythrocyte membrane include integral proteins, which span the entire width of the membrane, and peripheral proteins, which are attached to the inner or outer surface of the membrane. These proteins play a variety of roles, such as transporting molecules across the membrane, maintaining the shape of the erythrocyte, and interacting with other cells and proteins in the body.

The carbohydrates found in the erythrocyte membrane are attached to the outer surface of the membrane and help to identify the cell as part of the body's own immune system. They also play a role in cell-cell recognition and adhesion.

Overall, the erythrocyte membrane is a complex and dynamic structure that plays a critical role in maintaining the function and integrity of red blood cells.

High-Density Lipoproteins (HDL) are a type of lipoprotein that play a crucial role in the transportation and metabolism of cholesterol in the body. They are often referred to as "good" cholesterol because they help remove excess cholesterol from cells and carry it back to the liver, where it can be broken down and removed from the body. This process is known as reverse cholesterol transport.

HDLs are composed of a lipid core containing cholesteryl esters and triglycerides, surrounded by a shell of phospholipids, free cholesterol, and apolipoproteins, primarily apoA-I. The size and composition of HDL particles can vary, leading to the classification of different subclasses of HDL with varying functions and metabolic fates.

Elevated levels of HDL have been associated with a lower risk of developing cardiovascular diseases, while low HDL levels increase the risk. However, it is essential to consider that HDL function and quality may be more important than just the quantity in determining cardiovascular risk.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

Diacylglycerols (also known as diglycerides) are a type of glyceride, which is a compound that consists of glycerol and one or more fatty acids. Diacylglycerols contain two fatty acid chains bonded to a glycerol molecule through ester linkages. They are important intermediates in the metabolism of lipids and can be found in many types of food, including vegetable oils and dairy products. In the body, diacylglycerols can serve as a source of energy and can also play roles in cell signaling processes.

1-Acylglycerophosphocholine O-Acyltransferase is an enzyme that belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. It is responsible for catalyzing the reaction that transfers an acyl group from an acyl-CoA to the sn-2 position of 1-acylglycerophosphocholine, resulting in the formation of phosphatidylcholine, which is a major component of biological membranes. This enzyme plays a crucial role in lipid metabolism and has been implicated in various diseases, including atherosclerosis, non-alcoholic fatty liver disease, and cancer.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Fluorescence spectrometry is a type of analytical technique used to investigate the fluorescent properties of a sample. It involves the measurement of the intensity of light emitted by a substance when it absorbs light at a specific wavelength and then re-emits it at a longer wavelength. This process, known as fluorescence, occurs because the absorbed energy excites electrons in the molecules of the substance to higher energy states, and when these electrons return to their ground state, they release the excess energy as light.

Fluorescence spectrometry typically measures the emission spectrum of a sample, which is a plot of the intensity of emitted light versus the wavelength of emission. This technique can be used to identify and quantify the presence of specific fluorescent molecules in a sample, as well as to study their photophysical properties.

Fluorescence spectrometry has many applications in fields such as biochemistry, environmental science, and materials science. For example, it can be used to detect and measure the concentration of pollutants in water samples, to analyze the composition of complex biological mixtures, or to study the properties of fluorescent nanomaterials.

CDP-diacylglycerol-serine O-phosphatidyltransferase is an enzyme that plays a role in the synthesis of phosphatidylserine, a type of phospholipid found in cell membranes. The systematic name for this enzyme is CDP-diacylglycerol:L-serine O-phosphatidyltransferase. It catalyzes the following chemical reaction:

CDP-diacylglycerol + L-serine = CMP + O-phosphatidylserine

This enzyme is involved in the Kennedy pathway, which is the main pathway for the biosynthesis of glycerophospholipids in eukaryotic cells. CDP-diacylglycerol-serine O-phosphatidyltransferase is located in the endoplasmic reticulum and is essential for the synthesis of phosphatidylserine, which is an important structural component of cell membranes and also serves as a precursor for the biosynthesis of other phospholipids. Defects in this enzyme have been associated with neurological disorders.

Detergents are cleaning agents that are often used to remove dirt, grease, and stains from various surfaces. They contain one or more surfactants, which are compounds that lower the surface tension between two substances, such as water and oil, allowing them to mix more easily. This makes it possible for detergents to lift and suspend dirt particles in water so they can be rinsed away.

Detergents may also contain other ingredients, such as builders, which help to enhance the cleaning power of the surfactants by softening hard water or removing mineral deposits. Some detergents may also include fragrances, colorants, and other additives to improve their appearance or performance.

In a medical context, detergents are sometimes used as disinfectants or antiseptics, as they can help to kill bacteria, viruses, and other microorganisms on surfaces. However, it is important to note that not all detergents are effective against all types of microorganisms, and some may even be toxic or harmful if used improperly.

It is always important to follow the manufacturer's instructions when using any cleaning product, including detergents, to ensure that they are used safely and effectively.

In medical terms, membranes refer to thin layers of tissue that cover or line various structures in the body. They are composed of connective tissue and epithelial cells, and they can be found lining the outer surface of the body, internal organs, blood vessels, and nerves. There are several types of membranes in the human body, including:

1. Serous Membranes: These membranes line the inside of body cavities and cover the organs contained within them. They produce a lubricating fluid that reduces friction between the organ and the cavity wall. Examples include the pleura (lungs), pericardium (heart), and peritoneum (abdominal cavity).
2. Mucous Membranes: These membranes line the respiratory, gastrointestinal, and genitourinary tracts, as well as the inner surface of the eyelids and the nasal passages. They produce mucus to trap particles, bacteria, and other substances, which helps protect the body from infection.
3. Synovial Membranes: These membranes line the joint cavities and produce synovial fluid, which lubricates the joints and allows for smooth movement.
4. Meninges: These are three layers of membranes that cover and protect the brain and spinal cord. They include the dura mater (outermost layer), arachnoid mater (middle layer), and pia mater (innermost layer).
5. Amniotic Membrane: This is a thin, transparent membrane that surrounds and protects the fetus during pregnancy. It produces amniotic fluid, which provides a cushion for the developing baby and helps regulate its temperature.

Glycerol, also known as glycerine or glycerin, is a simple polyol (a sugar alcohol) with a sweet taste and a thick, syrupy consistency. It is a colorless, odorless, viscous liquid that is slightly soluble in water and freely miscible with ethanol and ether.

In the medical field, glycerol is often used as a medication or supplement. It can be used as a laxative to treat constipation, as a source of calories and energy for people who cannot eat by mouth, and as a way to prevent dehydration in people with certain medical conditions.

Glycerol is also used in the production of various medical products, such as medications, skin care products, and vaccines. It acts as a humectant, which means it helps to keep things moist, and it can also be used as a solvent or preservative.

In addition to its medical uses, glycerol is also widely used in the food industry as a sweetener, thickening agent, and moisture-retaining agent. It is generally recognized as safe (GRAS) by the U.S. Food and Drug Administration (FDA).

Arachidonic acids are a type of polyunsaturated fatty acid that is primarily found in the phospholipids of cell membranes. They contain 20 carbon atoms and four double bonds (20:4n-6), with the first double bond located at the sixth carbon atom from the methyl end.

Arachidonic acids are derived from linoleic acid, an essential fatty acid that cannot be synthesized by the human body and must be obtained through dietary sources such as meat, fish, and eggs. Once ingested, linoleic acid is converted to arachidonic acid in a series of enzymatic reactions.

Arachidonic acids play an important role in various physiological processes, including inflammation, immune response, and cell signaling. They serve as precursors for the synthesis of eicosanoids, which are signaling molecules that include prostaglandins, thromboxanes, and leukotrienes. These eicosanoids have diverse biological activities, such as modulating blood flow, platelet aggregation, and pain perception, among others.

However, excessive production of arachidonic acid-derived eicosanoids has been implicated in various pathological conditions, including inflammation, atherosclerosis, and cancer. Therefore, the regulation of arachidonic acid metabolism is an important area of research for the development of new therapeutic strategies.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

Triglycerides are the most common type of fat in the body, and they're found in the food we eat. They're carried in the bloodstream to provide energy to the cells in our body. High levels of triglycerides in the blood can increase the risk of heart disease, especially in combination with other risk factors such as high LDL (bad) cholesterol, low HDL (good) cholesterol, and high blood pressure.

It's important to note that while triglycerides are a type of fat, they should not be confused with cholesterol, which is a waxy substance found in the cells of our body. Both triglycerides and cholesterol are important for maintaining good health, but high levels of either can increase the risk of heart disease.

Triglyceride levels are measured through a blood test called a lipid panel or lipid profile. A normal triglyceride level is less than 150 mg/dL. Borderline-high levels range from 150 to 199 mg/dL, high levels range from 200 to 499 mg/dL, and very high levels are 500 mg/dL or higher.

Elevated triglycerides can be caused by various factors such as obesity, physical inactivity, excessive alcohol consumption, smoking, and certain medical conditions like diabetes, hypothyroidism, and kidney disease. Medications such as beta-blockers, steroids, and diuretics can also raise triglyceride levels.

Lifestyle changes such as losing weight, exercising regularly, eating a healthy diet low in saturated and trans fats, avoiding excessive alcohol consumption, and quitting smoking can help lower triglyceride levels. In some cases, medication may be necessary to reduce triglycerides to recommended levels.

Glycerophospholipids, also known as phosphoglycerides, are a major class of lipids that constitute the structural components of biological membranes. They are composed of a glycerol backbone to which two fatty acid chains and a phosphate group are attached. The phosphate group is esterified to an alcohol, typically choline, ethanolamine, serine, or inositol, forming what is called a phosphatidyl headgroup.

The chemical structure of glycerophospholipids allows them to form bilayers, which are essential for the formation of cell membranes and organelles within cells. The fatty acid chains, which can be saturated or unsaturated, contribute to the fluidity and permeability of the membrane. Glycerophospholipids also play important roles in various cellular processes, including signal transduction, cell recognition, and metabolism.

Oleic acid is a monounsaturated fatty acid that is commonly found in various natural oils such as olive oil, sunflower oil, and grapeseed oil. Its chemical formula is cis-9-octadecenoic acid, and it is a colorless liquid at room temperature. Oleic acid is an important component of human diet and has been shown to have potential health benefits, including reducing the risk of heart disease and improving immune function. It is also used in the manufacture of soaps, cosmetics, and other personal care products.

The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:

1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.

Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.

Apolipoprotein A-I (ApoA-I) is a major protein component of high-density lipoproteins (HDL) in human plasma. It plays a crucial role in the metabolism and transport of lipids, particularly cholesterol, within the body. ApoA-I facilitates the formation of HDL particles, which are involved in the reverse transport of cholesterol from peripheral tissues to the liver for excretion. This process is known as reverse cholesterol transport and helps maintain appropriate cholesterol levels in the body. Low levels of ApoA-I or dysfunctional ApoA-I have been associated with an increased risk of developing cardiovascular diseases.

Diphenylhexatriene (DPH) is a fluorescent chemical compound that is often used in research and scientific studies as a probe to investigate the properties and behavior of lipid membranes in cells. It is particularly useful for studying the mobility and orientation of lipids within membranes, as well as the fluidity and microviscosity of the membrane environment.

When DPH is incorporated into a lipid membrane, it can emit fluorescence when excited with light at a specific wavelength. The intensity and polarization of the emitted fluorescence can provide information about the motion and orientation of the DPH molecules, which in turn can reveal details about the physical properties of the membrane.

It's worth noting that while DPH is a valuable tool for studying lipid membranes, it is not typically used as a medical diagnostic or therapeutic agent.

Unilamellar liposomes are a type of liposome that consists of a single phospholipid bilayer membrane enclosing an aqueous compartment. They are spherical vesicles, ranging in size from 20 nanometers to several micrometers, and can be used as drug delivery systems for various therapeutic agents, including hydrophilic drugs (in the aqueous compartment) and hydrophobic drugs (incorporated into the lipid bilayer). The single membrane structure of unilamellar liposomes distinguishes them from multilamellar liposomes, which have multiple concentric phospholipid bilayers.

Hydrogen-ion concentration, also known as pH, is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm (to the base 10) of the hydrogen ion activity in a solution. The standard unit of measurement is the pH unit. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.

In medical terms, hydrogen-ion concentration is important for maintaining homeostasis within the body. For example, in the stomach, a high hydrogen-ion concentration (low pH) is necessary for the digestion of food. However, in other parts of the body such as blood, a high hydrogen-ion concentration can be harmful and lead to acidosis. Conversely, a low hydrogen-ion concentration (high pH) in the blood can lead to alkalosis. Both acidosis and alkalosis can have serious consequences on various organ systems if not corrected.

Chromatography, gas (GC) is a type of chromatographic technique used to separate, identify, and analyze volatile compounds or vapors. In this method, the sample mixture is vaporized and carried through a column packed with a stationary phase by an inert gas (carrier gas). The components of the mixture get separated based on their partitioning between the mobile and stationary phases due to differences in their adsorption/desorption rates or solubility.

The separated components elute at different times, depending on their interaction with the stationary phase, which can be detected and quantified by various detection systems like flame ionization detector (FID), thermal conductivity detector (TCD), electron capture detector (ECD), or mass spectrometer (MS). Gas chromatography is widely used in fields such as chemistry, biochemistry, environmental science, forensics, and food analysis.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Phosphatidylinositol 4,5-Diphosphate (PIP2) is a phospholipid molecule that plays a crucial role as a secondary messenger in various cell signaling pathways. It is a constituent of the inner leaflet of the plasma membrane and is formed by the phosphorylation of Phosphatidylinositol 4-Phosphate (PIP) at the 5th position of the inositol ring by enzyme Phosphoinositide kinase.

PIP2 is involved in several cellular processes, including regulation of ion channels, cytoskeleton dynamics, and membrane trafficking. It also acts as a substrate for the generation of two important secondary messengers, Inositol 1,4,5-Trisphosphate (IP3) and Diacylglycerol (DAG), which are produced by the action of Phospholipase C enzyme in response to various extracellular signals. These second messengers then mediate a variety of cellular responses such as calcium mobilization, gene expression, and cell proliferation.

Glycerides are esters formed from glycerol and one, two, or three fatty acids. They include monoglycerides (one fatty acid), diglycerides (two fatty acids), and triglycerides (three fatty acids). Triglycerides are the main constituents of natural fats and oils, and they are a major form of energy storage in animals and plants. High levels of triglycerides in the blood, also known as hypertriglyceridemia, can increase the risk of heart disease and stroke.

Palmitic acid is a type of saturated fatty acid, which is a common component in many foods and also produced by the body. Its chemical formula is C16:0, indicating that it contains 16 carbon atoms and no double bonds. Palmitic acid is found in high concentrations in animal fats, such as butter, lard, and beef tallow, as well as in some vegetable oils, like palm kernel oil and coconut oil.

In the human body, palmitic acid can be synthesized from other substances or absorbed through the diet. It plays a crucial role in various biological processes, including energy storage, membrane structure formation, and signaling pathways regulation. However, high intake of palmitic acid has been linked to an increased risk of developing cardiovascular diseases due to its potential to raise low-density lipoprotein (LDL) cholesterol levels in the blood.

It is essential to maintain a balanced diet and consume palmitic acid-rich foods in moderation, along with regular exercise and a healthy lifestyle, to reduce the risk of chronic diseases.

Phospholipase A1 (PLA1) is an enzyme that catalyzes the hydrolysis of the ester bond at the sn-1 position of glycerophospholipids, resulting in the production of free fatty acids and lysophospholipids. This enzyme plays a crucial role in various biological processes, including cell signaling, membrane remodeling, and inflammation. PLA1 is widely distributed in nature and can be found in different organisms, such as bacteria, plants, and animals. In humans, PLA1 is involved in several physiological and pathological conditions, including lipid metabolism, atherosclerosis, neurodegenerative diseases, and cancer.

Carrier proteins, also known as transport proteins, are a type of protein that facilitates the movement of molecules across cell membranes. They are responsible for the selective and active transport of ions, sugars, amino acids, and other molecules from one side of the membrane to the other, against their concentration gradient. This process requires energy, usually in the form of ATP (adenosine triphosphate).

Carrier proteins have a specific binding site for the molecule they transport, and undergo conformational changes upon binding, which allows them to move the molecule across the membrane. Once the molecule has been transported, the carrier protein returns to its original conformation, ready to bind and transport another molecule.

Carrier proteins play a crucial role in maintaining the balance of ions and other molecules inside and outside of cells, and are essential for many physiological processes, including nerve impulse transmission, muscle contraction, and nutrient uptake.

A Structure-Activity Relationship (SAR) in the context of medicinal chemistry and pharmacology refers to the relationship between the chemical structure of a drug or molecule and its biological activity or effect on a target protein, cell, or organism. SAR studies aim to identify patterns and correlations between structural features of a compound and its ability to interact with a specific biological target, leading to a desired therapeutic response or undesired side effects.

By analyzing the SAR, researchers can optimize the chemical structure of lead compounds to enhance their potency, selectivity, safety, and pharmacokinetic properties, ultimately guiding the design and development of novel drugs with improved efficacy and reduced toxicity.

Linoleic acid is a type of polyunsaturated fatty acid (PUFA) that is essential for human health. It is one of the two essential fatty acids, meaning that it cannot be produced by the body and must be obtained through diet.

Linoleic acid is a member of the omega-6 fatty acid family and has a chemical structure with two double bonds at the sixth and ninth carbon atoms from the methyl end of the molecule. It is found in various plant sources, such as vegetable oils (e.g., soybean, corn, safflower, and sunflower oils), nuts, seeds, and whole grains.

Linoleic acid plays a crucial role in maintaining the fluidity and function of cell membranes, producing eicosanoids (hormone-like substances that regulate various bodily functions), and supporting skin health. However, excessive intake of linoleic acid can lead to an imbalance between omega-6 and omega-3 fatty acids, which may contribute to inflammation and chronic diseases. Therefore, it is recommended to maintain a balanced diet with appropriate amounts of both omega-6 and omega-3 fatty acids.

Biological transport refers to the movement of molecules, ions, or solutes across biological membranes or through cells in living organisms. This process is essential for maintaining homeostasis, regulating cellular functions, and enabling communication between cells. There are two main types of biological transport: passive transport and active transport.

Passive transport does not require the input of energy and includes:

1. Diffusion: The random movement of molecules from an area of high concentration to an area of low concentration until equilibrium is reached.
2. Osmosis: The diffusion of solvent molecules (usually water) across a semi-permeable membrane from an area of lower solute concentration to an area of higher solute concentration.
3. Facilitated diffusion: The assisted passage of polar or charged substances through protein channels or carriers in the cell membrane, which increases the rate of diffusion without consuming energy.

Active transport requires the input of energy (in the form of ATP) and includes:

1. Primary active transport: The direct use of ATP to move molecules against their concentration gradient, often driven by specific transport proteins called pumps.
2. Secondary active transport: The coupling of the movement of one substance down its electrochemical gradient with the uphill transport of another substance, mediated by a shared transport protein. This process is also known as co-transport or counter-transport.

Cholesteryl esters are formed when cholesterol, a type of lipid (fat) that is important for the normal functioning of the body, becomes combined with fatty acids through a process called esterification. This results in a compound that is more hydrophobic (water-repelling) than cholesterol itself, which allows it to be stored more efficiently in the body.

Cholesteryl esters are found naturally in foods such as animal fats and oils, and they are also produced by the liver and other cells in the body. They play an important role in the structure and function of cell membranes, and they are also precursors to the synthesis of steroid hormones, bile acids, and vitamin D.

However, high levels of cholesteryl esters in the blood can contribute to the development of atherosclerosis, a condition characterized by the buildup of plaque in the arteries, which can increase the risk of heart disease and stroke. Cholesteryl esters are typically measured as part of a lipid profile, along with other markers such as total cholesterol, HDL cholesterol, and triglycerides.

Surface properties in the context of medical science refer to the characteristics and features of the outermost layer or surface of a biological material or structure, such as cells, tissues, organs, or medical devices. These properties can include physical attributes like roughness, smoothness, hydrophobicity or hydrophilicity, and electrical conductivity, as well as chemical properties like charge, reactivity, and composition.

In the field of biomaterials science, understanding surface properties is crucial for designing medical implants, devices, and drug delivery systems that can interact safely and effectively with biological tissues and fluids. Surface modifications, such as coatings or chemical treatments, can be used to alter surface properties and enhance biocompatibility, improve lubricity, reduce fouling, or promote specific cellular responses like adhesion, proliferation, or differentiation.

Similarly, in the field of cell biology, understanding surface properties is essential for studying cell-cell interactions, cell signaling, and cell behavior. Cells can sense and respond to changes in their environment, including variations in surface properties, which can influence cell shape, motility, and function. Therefore, characterizing and manipulating surface properties can provide valuable insights into the mechanisms of cellular processes and offer new strategies for developing therapies and treatments for various diseases.

Glycerophosphates are esters of glycerol and phosphoric acid. In the context of biochemistry and medicine, glycerophosphates often refer to glycerol 3-phosphate (also known as glyceraldehyde 3-phosphate or glycerone phosphate) and its derivatives.

Glycerol 3-phosphate plays a crucial role in cellular metabolism, particularly in the process of energy production and storage. It is an important intermediate in both glycolysis (the breakdown of glucose to produce energy) and gluconeogenesis (the synthesis of glucose from non-carbohydrate precursors).

In addition, glycerophosphates are also involved in the formation of phospholipids, a major component of cell membranes. The esterification of glycerol 3-phosphate with fatty acids leads to the synthesis of phosphatidic acid, which is a key intermediate in the biosynthesis of other phospholipids.

Abnormalities in glycerophosphate metabolism have been implicated in various diseases, including metabolic disorders and neurological conditions.

Lysophospholipids are a type of glycerophospholipid, which is a major component of cell membranes. They are characterized by having only one fatty acid chain attached to the glycerol backbone, as opposed to two in regular phospholipids. This results in a more polar and charged molecule, which can play important roles in cell signaling and regulation.

Lysophospholipids can be derived from the breakdown of regular phospholipids through the action of enzymes such as phospholipase A1 or A2. They can also be synthesized de novo in the cell. Some lysophospholipids, such as lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P), have been found to act as signaling molecules that bind to specific G protein-coupled receptors and regulate various cellular processes, including proliferation, survival, and migration.

Abnormal levels of lysophospholipids have been implicated in several diseases, such as cancer, inflammation, and neurological disorders. Therefore, understanding the biology of lysophospholipids has important implications for developing new therapeutic strategies.

4-Chloro-7-nitrobenzofurazan is not a medical term, but a chemical compound with the formula C6H2ClN3O4. It is an orange crystalline powder that is used in research and industrial applications, particularly as a reagent in chemical reactions. It is not a substance that is typically encountered in medical settings or treatments.

Acylation is a medical and biological term that refers to the process of introducing an acyl group (-CO-) into a molecule. This process can occur naturally or it can be induced through chemical reactions. In the context of medicine and biology, acylation often occurs during post-translational modifications of proteins, where an acyl group is added to specific amino acid residues, altering the protein's function, stability, or localization.

An example of acylation in medicine is the administration of neuraminidase inhibitors, such as oseltamivir (Tamiflu), for the treatment and prevention of influenza. These drugs work by inhibiting the activity of the viral neuraminidase enzyme, which is essential for the release of newly formed virus particles from infected cells. Oseltamivir is administered orally as an ethyl ester prodrug, which is then hydrolyzed in the body to form the active acylated metabolite that inhibits the viral neuraminidase.

In summary, acylation is a vital process in medicine and biology, with implications for drug design, protein function, and post-translational modifications.

Oxidation-Reduction (redox) reactions are a type of chemical reaction involving a transfer of electrons between two species. The substance that loses electrons in the reaction is oxidized, and the substance that gains electrons is reduced. Oxidation and reduction always occur together in a redox reaction, hence the term "oxidation-reduction."

In biological systems, redox reactions play a crucial role in many cellular processes, including energy production, metabolism, and signaling. The transfer of electrons in these reactions is often facilitated by specialized molecules called electron carriers, such as nicotinamide adenine dinucleotide (NAD+/NADH) and flavin adenine dinucleotide (FAD/FADH2).

The oxidation state of an element in a compound is a measure of the number of electrons that have been gained or lost relative to its neutral state. In redox reactions, the oxidation state of one or more elements changes as they gain or lose electrons. The substance that is oxidized has a higher oxidation state, while the substance that is reduced has a lower oxidation state.

Overall, oxidation-reduction reactions are fundamental to the functioning of living organisms and are involved in many important biological processes.

Fluorescence Polarization (FP) is not a medical term per se, but a technique used in medical research and diagnostics. Here's a general definition:

Fluorescence Polarization is a biophysical technique used to measure the rotational movement of molecules in solution after they have been excited by polarized light. When a fluorophore (a fluorescent molecule) absorbs light, its electrons become excited and then return to their ground state, releasing energy in the form of light. This emitted light often has different properties than the incident light, one of which can be its polarization. If the fluorophore is large or bound to a large structure, it may not rotate significantly during the time between absorption and emission, resulting in emitted light that maintains the same polarization as the excitation light. Conversely, if the fluorophore is small or unbound, it will rotate rapidly during this period, and the emitted light will be depolarized. By measuring the degree of polarization of the emitted light, researchers can gain information about the size, shape, and mobility of the fluorophore and the molecules to which it is attached. This technique is widely used in various fields including life sciences, biochemistry, and diagnostics.

Glycerol-3-Phosphate O-Acyltransferase (GPAT) is an enzyme that plays a crucial role in the biosynthesis of triacylglycerols and phospholipids, which are major components of cellular membranes and energy storage molecules. The GPAT enzyme catalyzes the initial and rate-limiting step in the glycerolipid synthesis pathway, specifically the transfer of an acyl group from an acyl-CoA donor to the sn-1 position of glycerol-3-phosphate, forming lysophosphatidic acid (LPA). This reaction is essential for the production of various glycerolipids, including phosphatidic acid, diacylglycerol, and triacylglycerol. There are four isoforms of GPAT (GPAT1-4) in humans, each with distinct subcellular localizations and functions. Dysregulation of GPAT activity has been implicated in several pathological conditions, such as metabolic disorders, cardiovascular diseases, and cancers.

An anion is an ion that has a negative electrical charge because it has more electrons than protons. The term "anion" is derived from the Greek word "anion," which means "to go up" or "to move upward." This name reflects the fact that anions are attracted to positively charged electrodes, or anodes, and will move toward them during electrolysis.

Anions can be formed when a neutral atom or molecule gains one or more extra electrons. For example, if a chlorine atom gains an electron, it becomes a chloride anion (Cl-). Anions are important in many chemical reactions and processes, including the conduction of electricity through solutions and the formation of salts.

In medicine, anions may be relevant in certain physiological processes, such as acid-base balance. For example, the concentration of anions such as bicarbonate (HCO3-) and chloride (Cl-) in the blood can affect the pH of the body fluids and help maintain normal acid-base balance. Abnormal levels of anions may indicate the presence of certain medical conditions, such as metabolic acidosis or alkalosis.

Acyltransferases are a group of enzymes that catalyze the transfer of an acyl group (a functional group consisting of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydrogen atom) from one molecule to another. This transfer involves the formation of an ester bond between the acyl group donor and the acyl group acceptor.

Acyltransferases play important roles in various biological processes, including the biosynthesis of lipids, fatty acids, and other metabolites. They are also involved in the detoxification of xenobiotics (foreign substances) by catalyzing the addition of an acyl group to these compounds, making them more water-soluble and easier to excrete from the body.

Examples of acyltransferases include serine palmitoyltransferase, which is involved in the biosynthesis of sphingolipids, and cholesteryl ester transfer protein (CETP), which facilitates the transfer of cholesteryl esters between lipoproteins.

Acyltransferases are classified based on the type of acyl group they transfer and the nature of the acyl group donor and acceptor molecules. They can be further categorized into subclasses based on their sequence similarities, three-dimensional structures, and evolutionary relationships.

Phospholipase D is an enzyme that catalyzes the hydrolysis of phosphatidylcholine and other glycerophospholipids to produce phosphatidic acid and a corresponding alcohol. This reaction plays a crucial role in various cellular processes, including signal transduction, membrane trafficking, and lipid metabolism. There are several isoforms of Phospholipase D identified in different tissues and organisms, each with distinct regulatory mechanisms and functions. The enzyme's activity can be modulated by various factors such as calcium ions, protein kinases, and G proteins, making it a critical component in the regulation of cellular homeostasis.

Phosphorylcholine is not a medical condition or disease, but rather a chemical compound. It is the choline ester of phosphoric acid, and it plays an important role in the structure and function of cell membranes. Phosphorylcholine is also found in certain types of lipoproteins, including low-density lipoprotein (LDL) or "bad" cholesterol.

In the context of medical research and therapy, phosphorylcholine has been studied for its potential role in various diseases, such as atherosclerosis, Alzheimer's disease, and other inflammatory conditions. Some studies have suggested that phosphorylcholine may contribute to the development of these diseases by promoting inflammation and immune responses. However, more research is needed to fully understand the role of phosphorylcholine in human health and disease.

Surface tension is not a term that has a specific medical definition. However, it is a physical chemistry concept that relates to the cohesive force between liquid molecules, causing the surface of the liquid to contract and have a higher intermolecular force than its bulk.

In a broader sense, surface tension can have implications in certain medical or biological contexts, such as the movement of liquids in the lungs or the stability of lipid bilayers in cell membranes. But it is not a term that is typically used to describe medical conditions or treatments.

Annexins are a family of calcium-dependent phospholipid-binding proteins that are found in various organisms, including humans. They are involved in several cellular processes, such as membrane organization, signal transduction, and regulation of ion channels. Some annexins also have roles in inflammation, blood coagulation, and apoptosis (programmed cell death).

Annexins have a conserved structure, consisting of a core domain that binds to calcium ions and a variable number of domains that bind to phospholipids. This allows annexins to interact with membranes in a calcium-dependent manner, which is important for their functions.

There are several different annexin proteins, each with its own specific functions and expression patterns. For example, annexin A1 is involved in the regulation of inflammation and has been studied as a potential target for anti-inflammatory therapies. Annexin A2 is involved in the regulation of coagulation and has been studied as a potential target for anticoagulant therapies. Other annexins have roles in cell division, differentiation, and survival.

Overall, annexins are important regulators of various cellular processes and have potential as targets for therapeutic intervention in a variety of diseases.

Electron microscopy (EM) is a type of microscopy that uses a beam of electrons to create an image of the sample being examined, resulting in much higher magnification and resolution than light microscopy. There are several types of electron microscopy, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), and reflection electron microscopy (REM).

In TEM, a beam of electrons is transmitted through a thin slice of the sample, and the electrons that pass through the sample are focused to form an image. This technique can provide detailed information about the internal structure of cells, viruses, and other biological specimens, as well as the composition and structure of materials at the atomic level.

In SEM, a beam of electrons is scanned across the surface of the sample, and the electrons that are scattered back from the surface are detected to create an image. This technique can provide information about the topography and composition of surfaces, as well as the structure of materials at the microscopic level.

REM is a variation of SEM in which the beam of electrons is reflected off the surface of the sample, rather than scattered back from it. This technique can provide information about the surface chemistry and composition of materials.

Electron microscopy has a wide range of applications in biology, medicine, and materials science, including the study of cellular structure and function, disease diagnosis, and the development of new materials and technologies.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

Diacylglycerol cholinephosphotransferase is an enzyme that plays a crucial role in the synthesis of phosphatidylcholine, which is a major component of biological membranes in animals and plants. The systematic name for this enzyme is CDP-choline:1,2-diacylglycerol cholinephosphotransferase.

The reaction catalyzed by this enzyme is as follows:
CDP-choline + 1,2-diacylglycerol → CMP + phosphatidylcholine

In this reaction, CDP-choline donates its phosphocholine headgroup to the acceptor molecule, diacylglycerol, forming phosphatidylcholine and releasing CMP as a byproduct. Phosphatidylcholine is an essential structural lipid in cell membranes and is also involved in various signaling pathways.

Deficiencies or mutations in the genes encoding this enzyme can lead to neurological disorders, highlighting its importance in maintaining proper cellular function.

Octoxynol is a type of surfactant, which is a compound that lowers the surface tension between two substances, such as oil and water. It is a synthetic chemical that is composed of repeating units of octylphenoxy polyethoxy ethanol.

Octoxynol is commonly used in medical applications as a spermicide, as it is able to disrupt the membrane of sperm cells and prevent them from fertilizing an egg. It is found in some contraceptive creams, gels, and films, and is also used as an ingredient in some personal care products such as shampoos and toothpastes.

In addition to its use as a spermicide, octoxynol has been studied for its potential antimicrobial properties, and has been shown to have activity against certain viruses, bacteria, and fungi. However, its use as an antimicrobial agent is not widely established.

It's important to note that octoxynol can cause irritation and allergic reactions in some people, and should be used with caution. Additionally, there is some concern about the potential for octoxynol to have harmful effects on the environment, as it has been shown to be toxic to aquatic organisms at high concentrations.

Lipoproteins are complex particles composed of multiple proteins and lipids (fats) that play a crucial role in the transport and metabolism of fat molecules in the body. They consist of an outer shell of phospholipids, free cholesterols, and apolipoproteins, enclosing a core of triglycerides and cholesteryl esters.

There are several types of lipoproteins, including:

1. Chylomicrons: These are the largest lipoproteins and are responsible for transporting dietary lipids from the intestines to other parts of the body.
2. Very-low-density lipoproteins (VLDL): Produced by the liver, VLDL particles carry triglycerides to peripheral tissues for energy storage or use.
3. Low-density lipoproteins (LDL): Often referred to as "bad cholesterol," LDL particles transport cholesterol from the liver to cells throughout the body. High levels of LDL in the blood can lead to plaque buildup in artery walls and increase the risk of heart disease.
4. High-density lipoproteins (HDL): Known as "good cholesterol," HDL particles help remove excess cholesterol from cells and transport it back to the liver for excretion or recycling. Higher levels of HDL are associated with a lower risk of heart disease.

Understanding lipoproteins and their roles in the body is essential for assessing cardiovascular health and managing risks related to heart disease and stroke.

Eicosapentaenoic acid (EPA) is a type of omega-3 fatty acid that is found in fish and some algae. It is a 20-carbon long polyunsaturated fatty acid with five double bonds, and has the chemical formula C20:5 n-3. EPA is an essential fatty acid, meaning that it cannot be produced by the human body and must be obtained through the diet.

EPA is a precursor to a group of hormone-like substances called eicosanoids, which include prostaglandins, thromboxanes, and leukotrienes. These compounds play important roles in regulating various physiological processes, such as inflammation, blood clotting, and immune function.

EPA has been studied for its potential health benefits, including reducing inflammation, lowering the risk of heart disease, and improving symptoms of depression. It is often taken as a dietary supplement in the form of fish oil or algal oil. However, it is important to note that while some studies have suggested potential health benefits of EPA, more research is needed to confirm these effects and establish recommended dosages.

Cytidine diphosphate choline (CDP-choline) is a biomolecule that plays a crucial role in the synthesis of phosphatidylcholine, a major component of cellular membranes. It is formed from the reaction between cytidine triphosphate (CTP) and choline, catalyzed by the enzyme CTP:phosphocholine cytidylyltransferase. CDP-choline serves as an essential intermediate in the Kennedy pathway of phosphatidylcholine synthesis. This molecule is also involved in various cellular processes, including signal transduction and neurotransmitter synthesis. CDP-choline has been studied for its potential therapeutic benefits in several neurological disorders due to its role in supporting membrane integrity and promoting neuronal health.

In the context of medical and biological sciences, a "binding site" refers to a specific location on a protein, molecule, or cell where another molecule can attach or bind. This binding interaction can lead to various functional changes in the original protein or molecule. The other molecule that binds to the binding site is often referred to as a ligand, which can be a small molecule, ion, or even another protein.

The binding between a ligand and its target binding site can be specific and selective, meaning that only certain ligands can bind to particular binding sites with high affinity. This specificity plays a crucial role in various biological processes, such as signal transduction, enzyme catalysis, or drug action.

In the case of drug development, understanding the location and properties of binding sites on target proteins is essential for designing drugs that can selectively bind to these sites and modulate protein function. This knowledge can help create more effective and safer therapeutic options for various diseases.

Medical definitions of water generally describe it as a colorless, odorless, tasteless liquid that is essential for all forms of life. It is a universal solvent, making it an excellent medium for transporting nutrients and waste products within the body. Water constitutes about 50-70% of an individual's body weight, depending on factors such as age, sex, and muscle mass.

In medical terms, water has several important functions in the human body:

1. Regulation of body temperature through perspiration and respiration.
2. Acting as a lubricant for joints and tissues.
3. Facilitating digestion by helping to break down food particles.
4. Transporting nutrients, oxygen, and waste products throughout the body.
5. Helping to maintain healthy skin and mucous membranes.
6. Assisting in the regulation of various bodily functions, such as blood pressure and heart rate.

Dehydration can occur when an individual does not consume enough water or loses too much fluid due to illness, exercise, or other factors. This can lead to a variety of symptoms, including dry mouth, fatigue, dizziness, and confusion. Severe dehydration can be life-threatening if left untreated.

CDP-diacylglycerol-inositol 3-phosphatidyltransferase is an enzyme that plays a role in the synthesis of phosphatidylinositol (PI) lipids, which are important components of cell membranes and also serve as secondary messengers in intracellular signaling pathways.

The enzyme catalyzes the transfer of a phosphate group from CDP-diacylglycerol to the 3-hydroxyl position of inositol, resulting in the formation of phosphatidylinositol 3-phosphate (PI3P). PI3P is a key signaling molecule that regulates various cellular processes, including membrane trafficking, autophagy, and inflammation.

CDP-diacylglycerol-inositol 3-phosphatidyltransferase is also known as phosphatidylinositol 3-kinase (PI3K) or type II PI3K, and it is distinct from the class I PI3Ks that are involved in growth factor signaling and oncogenesis. Mutations in CDP-diacylglycerol-inositol 3-phosphatidyltransferase have been implicated in various diseases, including cancer, neurodevelopmental disorders, and autoimmune diseases.

Cytidine diphosphate-diacylglycerol (CDP-DAG) is a bioactive lipid molecule that plays a crucial role in the synthesis of other lipids and is also involved in cell signaling pathways. It is formed from the reaction between cytidine diphosphocholine (CDP-choline) and phosphatidic acid, catalyzed by the enzyme CDP-choline:1,2-diacylglycerol cholinephosphotransferase.

CDP-DAG is a critical intermediate in the biosynthesis of several important lipids, including phosphatidylglycerol (PG), cardiolipin (CL), and platelet-activating factor (PAF). These lipids are essential components of cell membranes and have various functions in cell signaling, energy metabolism, and other physiological processes.

CDP-DAG also acts as a second messenger in intracellular signaling pathways, particularly those involved in the regulation of gene expression, cell proliferation, differentiation, and survival. It activates several protein kinases, including protein kinase C (PKC) isoforms, which phosphorylate and regulate various target proteins, leading to changes in their activity and function.

Abnormalities in CDP-DAG metabolism have been implicated in several diseases, including cancer, cardiovascular disease, and neurological disorders. Therefore, understanding the regulation and function of CDP-DAG and its downstream signaling pathways is an active area of research with potential therapeutic implications.

Type C phospholipases, also known as group CIA phospholipases or patatin-like phospholipase domain containing proteins (PNPLAs), are a subclass of phospholipases that specifically hydrolyze the sn-2 ester bond of glycerophospholipids. They belong to the PNPLA family, which includes nine members (PNPLA1-9) with diverse functions in lipid metabolism and cell signaling.

Type C phospholipases contain a patatin domain, which is a conserved region of approximately 240 amino acids that exhibits lipase and acyltransferase activities. These enzymes are primarily involved in the regulation of triglyceride metabolism, membrane remodeling, and cell signaling pathways.

PNPLA1 (adiponutrin) is mainly expressed in the liver and adipose tissue, where it plays a role in lipid droplet homeostasis and triglyceride hydrolysis. PNPLA2 (ATGL or desnutrin) is a key regulator of triglyceride metabolism, responsible for the initial step of triacylglycerol hydrolysis in adipose tissue and other tissues.

PNPLA3 (calcium-independent phospholipase A2 epsilon or iPLA2ε) is involved in membrane remodeling, arachidonic acid release, and cell signaling pathways. Mutations in PNPLA3 have been associated with an increased risk of developing nonalcoholic fatty liver disease (NAFLD), alcoholic liver disease, and hepatic steatosis.

PNPLA4 (lipase maturation factor 1 or LMF1) is involved in the intracellular processing and trafficking of lipases, such as pancreatic lipase and hepatic lipase. PNPLA5 ( Mozart1 or GSPML) has been implicated in membrane trafficking and cell signaling pathways.

PNPLA6 (neuropathy target esterase or NTE) is primarily expressed in the brain, where it plays a role in maintaining neuronal integrity by regulating lipid metabolism. Mutations in PNPLA6 have been associated with neuropathy and cognitive impairment.

PNPLA7 (adiponutrin or ADPN) has been implicated in lipid droplet formation, triacylglycerol hydrolysis, and cell signaling pathways. Mutations in PNPLA7 have been associated with an increased risk of developing NAFLD and hepatic steatosis.

PNPLA8 (diglyceride lipase or DGLα) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA9 (calcium-independent phospholipase A2 gamma or iPLA2γ) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA10 (calcium-independent phospholipase A2 delta or iPLA2δ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA11 (calcium-independent phospholipase A2 epsilon or iPLA2ε) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA12 (calcium-independent phospholipase A2 zeta or iPLA2ζ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA13 (calcium-independent phospholipase A2 eta or iPLA2η) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA14 (calcium-independent phospholipase A2 theta or iPLA2θ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA15 (calcium-independent phospholipase A2 iota or iPLA2ι) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA16 (calcium-independent phospholipase A2 kappa or iPLA2κ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA17 (calcium-independent phospholipase A2 lambda or iPLA2λ) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA18 (calcium-independent phospholipase A2 mu or iPLA2μ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA19 (calcium-independent phospholipase A2 nu or iPLA2ν) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA20 (calcium-independent phospholipase A2 xi or iPLA2ξ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA21 (calcium-independent phospholipase A2 omicron or iPLA2ο) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA22 (calcium-independent phospholipase A2 pi or iPLA2π) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA23 (calcium-independent phospholipase A2 rho or iPLA2ρ) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA24 (calcium-independent phospholipase A2 sigma or iPLA2σ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA25 (calcium-independent phospholipase A2 tau or iPLA2τ) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA26 (calcium-independent phospholipase A2 upsilon or iPLA2υ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA27 (calcium-independent phospholipase A2 phi or iPLA2φ) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA28 (calcium-independent phospholipase A2 chi or iPLA2χ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA29 (calcium-independent phospholipase A2 psi or iPLA2ψ) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA30 (calcium-independent phospholipase A2 omega or iPLA2ω) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA31 (calcium-independent phospholipase A2 pi or iPLA2π) has been implicated in membrane remodeling, arachidonic acid release, and cell signaling pathways.

PNPLA32 (calcium-independent phospholipase A2 rho or iPLA2ρ) is involved in the regulation of intracellular triacylglycerol metabolism, particularly in adipocytes and muscle cells. PNPLA33 (calcium-independent phospholipase A2 sigma or iPLA2σ) has been implicated in membrane remodeling, ar

Fluorescent dyes are substances that emit light upon excitation by absorbing light of a shorter wavelength. In a medical context, these dyes are often used in various diagnostic tests and procedures to highlight or mark certain structures or substances within the body. For example, fluorescent dyes may be used in imaging techniques such as fluorescence microscopy or fluorescence angiography to help visualize cells, tissues, or blood vessels. These dyes can also be used in flow cytometry to identify and sort specific types of cells. The choice of fluorescent dye depends on the specific application and the desired properties, such as excitation and emission spectra, quantum yield, and photostability.

Oleic acid is a monounsaturated fatty acid that is commonly found in various natural oils such as olive oil, sunflower oil, and peanut oil. Its chemical formula is cis-9-octadecenoic acid, and it is a colorless liquid at room temperature with a slight odor. Oleic acid is an important component of human diet and has been shown to have various health benefits, including reducing the risk of heart disease and improving immune function. It is also used in the manufacture of soaps, cosmetics, and other industrial products.

Annexin A5 is a protein that belongs to the annexin family, which are calcium-dependent phospholipid-binding proteins. Annexin A5 has high affinity for phosphatidylserine, a type of phospholipid that is usually located on the inner leaflet of the plasma membrane in healthy cells. However, when cells undergo apoptosis (programmed cell death), phosphatidylserine is exposed on the outer leaflet of the plasma membrane.

Annexin A5 can bind to exposed phosphatidylserine on the surface of apoptotic cells and is commonly used as a marker for detecting apoptosis in various experimental settings, including flow cytometry, immunohistochemistry, and imaging techniques. Annexin A5-based assays are widely used in research and clinical settings to study the mechanisms of apoptosis and to develop diagnostic tools for various diseases, such as cancer, neurodegenerative disorders, and cardiovascular diseases.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

I'm sorry for any confusion, but "thermodynamics" is not a term that has a specific medical definition. It is a branch of physics that deals with the relationships between heat and other forms of energy. However, the principles of thermodynamics can be applied to biological systems, including those in the human body, such as in the study of metabolism or muscle function. But in a medical context, "thermodynamics" would not be a term used independently as a diagnosis, treatment, or any medical condition.

Phosphates, in a medical context, refer to the salts or esters of phosphoric acid. Phosphates play crucial roles in various biological processes within the human body. They are essential components of bones and teeth, where they combine with calcium to form hydroxyapatite crystals. Phosphates also participate in energy transfer reactions as phosphate groups attached to adenosine diphosphate (ADP) and adenosine triphosphate (ATP). Additionally, they contribute to buffer systems that help maintain normal pH levels in the body.

Abnormal levels of phosphates in the blood can indicate certain medical conditions. High phosphate levels (hyperphosphatemia) may be associated with kidney dysfunction, hyperparathyroidism, or excessive intake of phosphate-containing products. Low phosphate levels (hypophosphatemia) might result from malnutrition, vitamin D deficiency, or certain diseases affecting the small intestine or kidneys. Both hypophosphatemia and hyperphosphatemia can have significant impacts on various organ systems and may require medical intervention.

A phase transition in the context of medicine and physiology often refers to the transformation of a substance or matter from one state to another within the body, typically in relation to temperature or pressure changes. However, I couldn't find a widely accepted medical definition for "phase transition."

In physics and chemistry, a phase transition is a process where a thermodynamic system changes from one phase or state of matter to another, such as:

1. Solid to liquid (melting)
2. Liquid to gas (vaporization)
3. Gas to liquid (condensation)
4. Solid to gas (sublimation)
5. Changes between different crystalline structures of the same substance (polymorphic phase transitions)

While not a direct medical definition, these concepts are relevant in various biochemical and physiological processes, such as protein folding, cell membrane fluidity, and temperature regulation in the body.

Glycolipids are a type of lipid (fat) molecule that contain one or more sugar molecules attached to them. They are important components of cell membranes, where they play a role in cell recognition and signaling. Glycolipids are also found on the surface of some viruses and bacteria, where they can be recognized by the immune system as foreign invaders.

There are several different types of glycolipids, including cerebrosides, gangliosides, and globosides. These molecules differ in the number and type of sugar molecules they contain, as well as the structure of their lipid tails. Glycolipids are synthesized in the endoplasmic reticulum and Golgi apparatus of cells, and they are transported to the cell membrane through vesicles.

Abnormalities in glycolipid metabolism or structure have been implicated in a number of diseases, including certain types of cancer, neurological disorders, and autoimmune diseases. For example, mutations in genes involved in the synthesis of glycolipids can lead to conditions such as Tay-Sachs disease and Gaucher's disease, which are characterized by the accumulation of abnormal glycolipids in cells.

Enzyme activation refers to the process by which an enzyme becomes biologically active and capable of carrying out its specific chemical or biological reaction. This is often achieved through various post-translational modifications, such as proteolytic cleavage, phosphorylation, or addition of cofactors or prosthetic groups to the enzyme molecule. These modifications can change the conformation or structure of the enzyme, exposing or creating a binding site for the substrate and allowing the enzymatic reaction to occur.

For example, in the case of proteolytic cleavage, an inactive precursor enzyme, known as a zymogen, is cleaved into its active form by a specific protease. This is seen in enzymes such as trypsin and chymotrypsin, which are initially produced in the pancreas as inactive precursors called trypsinogen and chymotrypsinogen, respectively. Once they reach the small intestine, they are activated by enteropeptidase, a protease that cleaves a specific peptide bond, releasing the active enzyme.

Phosphorylation is another common mechanism of enzyme activation, where a phosphate group is added to a specific serine, threonine, or tyrosine residue on the enzyme by a protein kinase. This modification can alter the conformation of the enzyme and create a binding site for the substrate, allowing the enzymatic reaction to occur.

Enzyme activation is a crucial process in many biological pathways, as it allows for precise control over when and where specific reactions take place. It also provides a mechanism for regulating enzyme activity in response to various signals and stimuli, such as hormones, neurotransmitters, or changes in the intracellular environment.

"Laureates" is not a medical term. However, if you are referring to "laurates" as a salt or ester of lauric acid, then here's the definition:

Laurates are organic compounds that contain a laurate group, which is the anion (negatively charged ion) derived from lauric acid. Lauric acid is a saturated fatty acid with a 12-carbon chain, and its anion has the chemical formula CH3(CH2)10COO-.

Laurates can be formed by reacting lauric acid with a base to form a salt (e.g., sodium laurate, potassium laurate) or by reacting it with an alcohol to form an ester (e.g., methyl laurate, ethyl laurate). These compounds have various applications in industry, including as surfactants, emulsifiers, and solubilizers in personal care products, cosmetics, and pharmaceuticals.

Lecithins are a group of naturally occurring compounds called phospholipids, which are essential components of biological membranes. They are composed of a molecule that contains a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails. This unique structure allows lecithins to act as emulsifiers, helping to mix oil-based and water-based substances together.

Lecithins are found in various foods such as egg yolks, soybeans, sunflower seeds, and some other plants. In the medical field, lecithins may be used in dietary supplements or as a component of nutritional support for patients with certain conditions. They have been studied for their potential benefits in improving liver function, supporting brain health, and reducing cholesterol levels; however, more research is needed to confirm these effects and establish recommended dosages.

Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.

Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.

Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.

Prothrombin is a protein present in blood plasma, and it's also known as coagulation factor II. It plays a crucial role in the coagulation cascade, which is a complex series of reactions that leads to the formation of a blood clot.

When an injury occurs, the coagulation cascade is initiated to prevent excessive blood loss. Prothrombin is converted into its active form, thrombin, by another factor called factor Xa in the presence of calcium ions, phospholipids, and factor Va. Thrombin then catalyzes the conversion of fibrinogen into fibrin, forming a stable clot.

Prothrombin levels can be measured through a blood test, which is often used to diagnose or monitor conditions related to bleeding or coagulation disorders, such as liver disease or vitamin K deficiency.

Biophysical phenomena refer to the observable events and processes that occur in living organisms, which can be explained and studied using the principles and methods of physics. These phenomena can include a wide range of biological processes at various levels of organization, from molecular interactions to whole-organism behaviors. Examples of biophysical phenomena include the mechanics of muscle contraction, the electrical activity of neurons, the transport of molecules across cell membranes, and the optical properties of biological tissues. By applying physical theories and techniques to the study of living systems, biophysicists seek to better understand the fundamental principles that govern life and to develop new approaches for diagnosing and treating diseases.

Ethanolamines are a class of organic compounds that contain an amino group (-NH2) and a hydroxyl group (-OH) attached to a carbon atom. They are derivatives of ammonia (NH3) in which one or two hydrogen atoms have been replaced by a ethanol group (-CH2CH2OH).

The most common ethanolamines are:

* Monethanolamine (MEA), also called 2-aminoethanol, with the formula HOCH2CH2NH2.
* Diethanolamine (DEA), also called 2,2'-iminobisethanol, with the formula HOCH2CH2NHCH2CH2OH.
* Triethanolamine (TEA), also called 2,2',2''-nitrilotrisethanol, with the formula N(CH2CH2OH)3.

Ethanolamines are used in a wide range of industrial and consumer products, including as solvents, emulsifiers, detergents, pharmaceuticals, and personal care products. They also have applications as intermediates in the synthesis of other chemicals. In the body, ethanolamines play important roles in various biological processes, such as neurotransmission and cell signaling.

Linoleic acid is an essential polyunsaturated fatty acid, specifically an omega-6 fatty acid. It is called "essential" because our bodies cannot produce it; therefore, it must be obtained through our diet. Linoleic acid is a crucial component of cell membranes and is involved in the production of prostaglandins, which are hormone-like substances that regulate various bodily functions such as inflammation, blood pressure, and muscle contraction.

Foods rich in linoleic acid include vegetable oils (such as soybean, corn, and sunflower oil), nuts, seeds, and some fruits and vegetables. It is important to maintain a balance between omega-6 and omega-3 fatty acids in the diet, as excessive consumption of omega-6 fatty acids can contribute to inflammation and other health issues.

Omega-3 fatty acids are a type of polyunsaturated fats that are essential for human health. The "omega-3" designation refers to the location of a double bond in the chemical structure of the fatty acid, specifically three carbon atoms from the end of the molecule.

There are three main types of omega-3 fatty acids: eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). EPA and DHA are primarily found in fatty fish, such as salmon, mackerel, and sardines, as well as in algae. ALA is found in plant sources, such as flaxseeds, chia seeds, walnuts, and some vegetable oils.

Omega-3 fatty acids have been shown to have numerous health benefits, including reducing inflammation, lowering the risk of heart disease, improving brain function, and supporting eye health. They are also important for fetal development during pregnancy and breastfeeding. It is recommended that adults consume at least 250-500 milligrams of combined EPA and DHA per day, although higher intakes may be beneficial for certain conditions. ALA can be converted to EPA and DHA in the body, but this process is not very efficient, so it is important to consume preformed EPA and DHA from dietary sources or supplements.

Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.

Examples of biological models include:

1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.

Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.

Erythrocytes, also known as red blood cells (RBCs), are the most common type of blood cell in circulating blood in mammals. They are responsible for transporting oxygen from the lungs to the body's tissues and carbon dioxide from the tissues to the lungs.

Erythrocytes are formed in the bone marrow and have a biconcave shape, which allows them to fold and bend easily as they pass through narrow blood vessels. They do not have a nucleus or mitochondria, which makes them more flexible but also limits their ability to reproduce or repair themselves.

In humans, erythrocytes are typically disc-shaped and measure about 7 micrometers in diameter. They contain the protein hemoglobin, which binds to oxygen and gives blood its red color. The lifespan of an erythrocyte is approximately 120 days, after which it is broken down in the liver and spleen.

Abnormalities in erythrocyte count or function can lead to various medical conditions, such as anemia, polycythemia, and sickle cell disease.

Phosphatidylinositol phosphates (PIPs) are a family of lipid molecules that play crucial roles as secondary messengers in intracellular signaling pathways. They are formed by the phosphorylation of the hydroxyl group on the inositol ring of phosphatidylinositol (PI), a fundamental component of cell membranes.

There are seven main types of PIPs, classified based on the number and position of phosphate groups attached to the inositol ring:

1. Phosphatidylinositol 4-monophosphate (PI4P) - one phosphate group at the 4th position
2. Phosphatidylinositol 5-monophosphate (PI5P) - one phosphate group at the 5th position
3. Phosphatidylinositol 3,4-bisphosphate (PI(3,4)P2) - two phosphate groups at the 3rd and 4th positions
4. Phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2) - two phosphate groups at the 3rd and 5th positions
5. Phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] - two phosphate groups at the 4th and 5th positions
6. Phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3] - three phosphate groups at the 3rd, 4th, and 5th positions
7. Phosphatidylinositol 3-phosphate (PI3P) - one phosphate group at the 3rd position

These PIPs are involved in various cellular processes such as membrane trafficking, cytoskeleton organization, cell survival, and metabolism. Dysregulation of PIP metabolism has been implicated in several diseases, including cancer, diabetes, and neurological disorders.

"Inbred strains of rats" are genetically identical rodents that have been produced through many generations of brother-sister mating. This results in a high degree of homozygosity, where the genes at any particular locus in the genome are identical in all members of the strain.

Inbred strains of rats are widely used in biomedical research because they provide a consistent and reproducible genetic background for studying various biological phenomena, including the effects of drugs, environmental factors, and genetic mutations on health and disease. Additionally, inbred strains can be used to create genetically modified models of human diseases by introducing specific mutations into their genomes.

Some commonly used inbred strains of rats include the Wistar Kyoto (WKY), Sprague-Dawley (SD), and Fischer 344 (F344) rat strains. Each strain has its own unique genetic characteristics, making them suitable for different types of research.

Molecular structure, in the context of biochemistry and molecular biology, refers to the arrangement and organization of atoms and chemical bonds within a molecule. It describes the three-dimensional layout of the constituent elements, including their spatial relationships, bond lengths, and angles. Understanding molecular structure is crucial for elucidating the functions and reactivities of biological macromolecules such as proteins, nucleic acids, lipids, and carbohydrates. Various experimental techniques, like X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cryo-electron microscopy (cryo-EM), are employed to determine molecular structures at atomic resolution, providing valuable insights into their biological roles and potential therapeutic targets.

"Spin labels" are a term used in the field of magnetic resonance, including nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR). They refer to molecules or atoms that have been chemically attached to a system of interest and possess a stable, unpaired electron. This unpaired electron behaves like a tiny magnet and can be manipulated using magnetic fields and radiofrequency pulses in EPR experiments. The resulting changes in the electron's spin state can provide information about the local environment, dynamics, and structure of the system to which it is attached. Spin labels are often used in biochemistry and materials science to study complex biological systems or materials at the molecular level.

High-performance liquid chromatography (HPLC) is a type of chromatography that separates and analyzes compounds based on their interactions with a stationary phase and a mobile phase under high pressure. The mobile phase, which can be a gas or liquid, carries the sample mixture through a column containing the stationary phase.

In HPLC, the mobile phase is a liquid, and it is pumped through the column at high pressures (up to several hundred atmospheres) to achieve faster separation times and better resolution than other types of liquid chromatography. The stationary phase can be a solid or a liquid supported on a solid, and it interacts differently with each component in the sample mixture, causing them to separate as they travel through the column.

HPLC is widely used in analytical chemistry, pharmaceuticals, biotechnology, and other fields to separate, identify, and quantify compounds present in complex mixtures. It can be used to analyze a wide range of substances, including drugs, hormones, vitamins, pigments, flavors, and pollutants. HPLC is also used in the preparation of pure samples for further study or use.

Biophysics is a interdisciplinary field that combines the principles and methods of physics with those of biology to study biological systems and phenomena. It involves the use of physical theories, models, and techniques to understand and explain the properties, functions, and behaviors of living organisms and their constituents, such as cells, proteins, and DNA.

Biophysics can be applied to various areas of biology, including molecular biology, cell biology, neuroscience, and physiology. It can help elucidate the mechanisms of biological processes at the molecular and cellular levels, such as protein folding, ion transport, enzyme kinetics, gene expression, and signal transduction. Biophysical methods can also be used to develop diagnostic and therapeutic tools for medical applications, such as medical imaging, drug delivery, and gene therapy.

Examples of biophysical techniques include X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, electron microscopy, fluorescence microscopy, atomic force microscopy, and computational modeling. These methods allow researchers to probe the structure, dynamics, and interactions of biological molecules and systems with high precision and resolution, providing insights into their functions and behaviors.

Intracellular membranes refer to the membrane structures that exist within a eukaryotic cell (excluding bacteria and archaea, which are prokaryotic and do not have intracellular membranes). These membranes compartmentalize the cell, creating distinct organelles or functional regions with specific roles in various cellular processes.

Major types of intracellular membranes include:

1. Nuclear membrane (nuclear envelope): A double-membraned structure that surrounds and protects the genetic material within the nucleus. It consists of an outer and inner membrane, perforated by nuclear pores that regulate the transport of molecules between the nucleus and cytoplasm.
2. Endoplasmic reticulum (ER): An extensive network of interconnected tubules and sacs that serve as a major site for protein folding, modification, and lipid synthesis. The ER has two types: rough ER (with ribosomes on its surface) and smooth ER (without ribosomes).
3. Golgi apparatus/Golgi complex: A series of stacked membrane-bound compartments that process, sort, and modify proteins and lipids before they are transported to their final destinations within the cell or secreted out of the cell.
4. Lysosomes: Membrane-bound organelles containing hydrolytic enzymes for breaking down various biomolecules (proteins, carbohydrates, lipids, and nucleic acids) in the process called autophagy or from outside the cell via endocytosis.
5. Peroxisomes: Single-membrane organelles involved in various metabolic processes, such as fatty acid oxidation and detoxification of harmful substances like hydrogen peroxide.
6. Vacuoles: Membrane-bound compartments that store and transport various molecules, including nutrients, waste products, and enzymes. Plant cells have a large central vacuole for maintaining turgor pressure and storing metabolites.
7. Mitochondria: Double-membraned organelles responsible for generating energy (ATP) through oxidative phosphorylation and other metabolic processes, such as the citric acid cycle and fatty acid synthesis.
8. Chloroplasts: Double-membraned organelles found in plant cells that convert light energy into chemical energy during photosynthesis, producing oxygen and organic compounds (glucose) from carbon dioxide and water.
9. Endoplasmic reticulum (ER): A network of interconnected membrane-bound tubules involved in protein folding, modification, and transport; it is divided into two types: rough ER (with ribosomes on the surface) and smooth ER (without ribosomes).
10. Nucleus: Double-membraned organelle containing genetic material (DNA) and associated proteins involved in replication, transcription, RNA processing, and DNA repair. The nuclear membrane separates the nucleoplasm from the cytoplasm and contains nuclear pores for transporting molecules between the two compartments.

Essential fatty acids (EFAs) are a type of fatty acid that cannot be synthesized by the human body and must be obtained through diet. There are two main types of essential fatty acids: linoleic acid (omega-6) and alpha-linolenic acid (omega-3).

Linoleic acid is found in foods such as vegetable oils, nuts, and seeds, while alpha-linolenic acid is found in foods such as flaxseeds, walnuts, and fatty fish. These essential fatty acids play important roles in the body, including maintaining the fluidity and function of cell membranes, producing eicosanoids (hormone-like substances that regulate various bodily functions), and supporting the development and function of the brain and nervous system.

Deficiency in essential fatty acids can lead to a variety of health problems, including skin disorders, poor growth and development, and increased risk of heart disease. It is important to maintain a balanced intake of both omega-6 and omega-3 fatty acids, as excessive consumption of omega-6 relative to omega-3 has been linked to inflammation and chronic diseases.

Surfactants, also known as surface-active agents, are amphiphilic compounds that reduce the surface tension between two liquids or between a liquid and a solid. They contain both hydrophilic (water-soluble) and hydrophobic (water-insoluble) components in their molecular structure. This unique property allows them to interact with and stabilize interfaces, making them useful in various medical and healthcare applications.

In the medical field, surfactants are commonly used in pulmonary medicine, particularly for treating respiratory distress syndrome (RDS) in premature infants. The lungs of premature infants often lack sufficient amounts of natural lung surfactant, which can lead to RDS and other complications. Exogenous surfactants, derived from animal sources or synthetically produced, are administered to replace the missing or dysfunctional lung surfactant, improving lung compliance and gas exchange.

Surfactants also have applications in topical formulations for dermatology, as they can enhance drug penetration into the skin, reduce irritation, and improve the spreadability of creams and ointments. Additionally, they are used in diagnostic imaging to enhance contrast between tissues and improve visualization during procedures such as ultrasound and X-ray examinations.

Amino alcohols are organic compounds containing both amine and hydroxyl (alcohol) functional groups. They have the general structure R-NH-OH, where R represents a carbon-containing group. Amino alcohols can be primary, secondary, or tertiary, depending on the number of alkyl or aryl groups attached to the nitrogen atom.

These compounds are important in many chemical and biological processes. For example, some amino alcohols serve as intermediates in the synthesis of pharmaceuticals, dyes, and polymers. In biochemistry, certain amino alcohols function as neurotransmitters or components of lipids.

Some common examples of amino alcohols include:

* Ethanolamine (monoethanolamine, MEA): a primary amino alcohol used in the production of detergents, emulsifiers, and pharmaceuticals
* Serinol: a primary amino alcohol that occurs naturally in some foods and is used as a flavoring agent
* Choline: a quaternary ammonium compound with a hydroxyl group, essential for human nutrition and found in various foods such as eggs, liver, and peanuts
* Trimethylamine (TMA): a tertiary amino alcohol that occurs naturally in some marine animals and is responsible for the "fishy" odor of their flesh.

Tritium is not a medical term, but it is a term used in the field of nuclear physics and chemistry. Tritium (symbol: T or 3H) is a radioactive isotope of hydrogen with two neutrons and one proton in its nucleus. It is also known as heavy hydrogen or superheavy hydrogen.

Tritium has a half-life of about 12.3 years, which means that it decays by emitting a low-energy beta particle (an electron) to become helium-3. Due to its radioactive nature and relatively short half-life, tritium is used in various applications, including nuclear weapons, fusion reactors, luminous paints, and medical research.

In the context of medicine, tritium may be used as a radioactive tracer in some scientific studies or medical research, but it is not a term commonly used to describe a medical condition or treatment.

Microsomes are subcellular membranous vesicles that are obtained as a byproduct during the preparation of cellular homogenates. They are not naturally occurring structures within the cell, but rather formed due to fragmentation of the endoplasmic reticulum (ER) during laboratory procedures. Microsomes are widely used in various research and scientific studies, particularly in the fields of biochemistry and pharmacology.

Microsomes are rich in enzymes, including the cytochrome P450 system, which is involved in the metabolism of drugs, toxins, and other xenobiotics. These enzymes play a crucial role in detoxifying foreign substances and eliminating them from the body. As such, microsomes serve as an essential tool for studying drug metabolism, toxicity, and interactions, allowing researchers to better understand and predict the effects of various compounds on living organisms.

A chemical model is a simplified representation or description of a chemical system, based on the laws of chemistry and physics. It is used to explain and predict the behavior of chemicals and chemical reactions. Chemical models can take many forms, including mathematical equations, diagrams, and computer simulations. They are often used in research, education, and industry to understand complex chemical processes and develop new products and technologies.

For example, a chemical model might be used to describe the way that atoms and molecules interact in a particular reaction, or to predict the properties of a new material. Chemical models can also be used to study the behavior of chemicals at the molecular level, such as how they bind to each other or how they are affected by changes in temperature or pressure.

It is important to note that chemical models are simplifications of reality and may not always accurately represent every aspect of a chemical system. They should be used with caution and validated against experimental data whenever possible.

In medical terms, 'air' is defined as the mixture of gases that make up the Earth's atmosphere. It primarily consists of nitrogen (78%), oxygen (21%), and small amounts of other gases such as argon, carbon dioxide, and trace amounts of neon, helium, and methane.

Air is essential for human life, as it provides the oxygen that our bodies need to produce energy through respiration. We inhale air into our lungs, where oxygen is absorbed into the bloodstream and transported to cells throughout the body. At the same time, carbon dioxide, a waste product of cellular metabolism, is exhaled out of the body through the lungs and back into the atmosphere.

In addition to its role in respiration, air also plays a critical role in regulating the Earth's climate and weather patterns, as well as serving as a medium for sound waves and other forms of energy transfer.

Platelet-activating factor (PAF) is a potent phospholipid mediator that plays a significant role in various inflammatory and immune responses. It is a powerful lipid signaling molecule released mainly by activated platelets, neutrophils, monocytes, endothelial cells, and other cell types during inflammation or injury.

PAF has a molecular structure consisting of an alkyl chain linked to a glycerol moiety, a phosphate group, and an sn-2 acetyl group. This unique structure allows PAF to bind to its specific G protein-coupled receptor (PAF-R) on the surface of target cells, triggering various intracellular signaling cascades that result in cell activation, degranulation, and aggregation.

The primary functions of PAF include:

1. Platelet activation and aggregation: PAF stimulates platelets to aggregate, release their granules, and activate the coagulation cascade, which can lead to thrombus formation.
2. Neutrophil and monocyte activation: PAF activates these immune cells, leading to increased adhesion, degranulation, and production of reactive oxygen species (ROS) and pro-inflammatory cytokines.
3. Vasodilation and increased vascular permeability: PAF can cause vasodilation by acting on endothelial cells, leading to an increase in blood flow and facilitating the extravasation of immune cells into inflamed tissues.
4. Bronchoconstriction: In the respiratory system, PAF can induce bronchoconstriction and recruitment of inflammatory cells, contributing to asthma symptoms.
5. Neurotransmission modulation: PAF has been implicated in neuroinflammation and may play a role in neuronal excitability, synaptic plasticity, and cognitive functions.

Dysregulated PAF signaling has been associated with several pathological conditions, including atherosclerosis, sepsis, acute respiratory distress syndrome (ARDS), ischemia-reperfusion injury, and neuroinflammatory disorders. Therefore, targeting the PAF pathway may provide therapeutic benefits in these diseases.

Low-density lipoproteins (LDL), also known as "bad cholesterol," are a type of lipoprotein that carry cholesterol and other fats from the liver to cells throughout the body. High levels of LDL in the blood can lead to the buildup of cholesterol in the walls of the arteries, which can increase the risk of heart disease and stroke.

Lipoproteins are complex particles composed of proteins (apolipoproteins) and lipids (cholesterol, triglycerides, and phospholipids) that are responsible for transporting fat molecules around the body in the bloodstream. LDL is one type of lipoprotein, along with high-density lipoproteins (HDL), very low-density lipoproteins (VLDL), and chylomicrons.

LDL particles are smaller than HDL particles and can easily penetrate the artery walls, leading to the formation of plaques that can narrow or block the arteries. Therefore, maintaining healthy levels of LDL in the blood is essential for preventing cardiovascular disease.

Solubility is a fundamental concept in pharmaceutical sciences and medicine, which refers to the maximum amount of a substance (solute) that can be dissolved in a given quantity of solvent (usually water) at a specific temperature and pressure. Solubility is typically expressed as mass of solute per volume or mass of solvent (e.g., grams per liter, milligrams per milliliter). The process of dissolving a solute in a solvent results in a homogeneous solution where the solute particles are dispersed uniformly throughout the solvent.

Understanding the solubility of drugs is crucial for their formulation, administration, and therapeutic effectiveness. Drugs with low solubility may not dissolve sufficiently to produce the desired pharmacological effect, while those with high solubility might lead to rapid absorption and short duration of action. Therefore, optimizing drug solubility through various techniques like particle size reduction, salt formation, or solubilization is an essential aspect of drug development and delivery.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

Beta 2-glycoprotein I, also known as apolipoprotein H, is a plasma protein that belongs to the family of proteins called immunoglobulin-binding proteins. It has a molecular weight of approximately 44 kDa and is composed of five domains with similar structures.

Beta 2-glycoprotein I is primarily produced in the liver and circulates in the bloodstream, where it plays a role in several physiological processes, including coagulation, complement activation, and lipid metabolism. It has been identified as an autoantigen in certain autoimmune disorders, such as antiphospholipid syndrome (APS), where autoantibodies against beta 2-glycoprotein I can cause blood clots, miscarriages, and other complications.

In medical terminology, the definition of "beta 2-glycoprotein I" is as follows:

A plasma protein that belongs to the family of immunoglobulin-binding proteins and has a molecular weight of approximately 44 kDa. It is primarily produced in the liver and circulates in the bloodstream, where it plays a role in several physiological processes, including coagulation, complement activation, and lipid metabolism. Autoantibodies against beta 2-glycoprotein I are associated with certain autoimmune disorders, such as antiphospholipid syndrome (APS), where they can cause blood clots, miscarriages, and other complications.

Sterols are a type of organic compound that is derived from steroids and found in the cell membranes of organisms. In animals, including humans, cholesterol is the most well-known sterol. Sterols help to maintain the structural integrity and fluidity of cell membranes, and they also play important roles as precursors for the synthesis of various hormones and other signaling molecules. Phytosterols are plant sterols that have been shown to have cholesterol-lowering effects in humans when consumed in sufficient amounts.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Bile is a digestive fluid that is produced by the liver and stored in the gallbladder. It plays an essential role in the digestion and absorption of fats and fat-soluble vitamins in the small intestine. Bile consists of bile salts, bilirubin, cholesterol, phospholipids, electrolytes, and water.

Bile salts are amphipathic molecules that help to emulsify fats into smaller droplets, increasing their surface area and allowing for more efficient digestion by enzymes such as lipase. Bilirubin is a breakdown product of hemoglobin from red blood cells and gives bile its characteristic greenish-brown color.

Bile is released into the small intestine in response to food, particularly fats, entering the digestive tract. It helps to break down large fat molecules into smaller ones that can be absorbed through the walls of the intestines and transported to other parts of the body for energy or storage.

Factor V, also known as proaccelerin or labile factor, is a protein involved in the coagulation cascade, which is a series of chemical reactions that leads to the formation of a blood clot. Factor V acts as a cofactor for the conversion of prothrombin to thrombin, which is a critical step in the coagulation process.

Inherited deficiencies or abnormalities in Factor V can lead to bleeding disorders. For example, Factor V Leiden is a genetic mutation that causes an increased risk of blood clots, while Factor V deficiency can cause a bleeding disorder.

It's worth noting that "Factor Va" is not a standard medical term. Factor V becomes activated and turns into Factor Va during the coagulation cascade. Therefore, it is possible that you are looking for the definition of "Factor Va" in the context of its role as an activated form of Factor V in the coagulation process.

Carbon radioisotopes are radioactive isotopes of carbon, which is an naturally occurring chemical element with the atomic number 6. The most common and stable isotope of carbon is carbon-12 (^12C), but there are also several radioactive isotopes, including carbon-11 (^11C), carbon-14 (^14C), and carbon-13 (^13C). These radioisotopes have different numbers of neutrons in their nuclei, which makes them unstable and causes them to emit radiation.

Carbon-11 has a half-life of about 20 minutes and is used in medical imaging techniques such as positron emission tomography (PET) scans. It is produced by bombarding nitrogen-14 with protons in a cyclotron.

Carbon-14, also known as radiocarbon, has a half-life of about 5730 years and is used in archaeology and geology to date organic materials. It is produced naturally in the atmosphere by cosmic rays.

Carbon-13 is stable and has a natural abundance of about 1.1% in carbon. It is not radioactive, but it can be used as a tracer in medical research and in the study of metabolic processes.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Circular dichroism (CD) is a technique used in physics and chemistry to study the structure of molecules, particularly large biological molecules such as proteins and nucleic acids. It measures the difference in absorption of left-handed and right-handed circularly polarized light by a sample. This difference in absorption can provide information about the three-dimensional structure of the molecule, including its chirality or "handedness."

In more technical terms, CD is a form of spectroscopy that measures the differential absorption of left and right circularly polarized light as a function of wavelength. The CD signal is measured in units of millidegrees (mdeg) and can be positive or negative, depending on the type of chromophore and its orientation within the molecule.

CD spectra can provide valuable information about the secondary and tertiary structure of proteins, as well as the conformation of nucleic acids. For example, alpha-helical proteins typically exhibit a strong positive band near 190 nm and two negative bands at around 208 nm and 222 nm, while beta-sheet proteins show a strong positive band near 195 nm and two negative bands at around 217 nm and 175 nm.

CD spectroscopy is a powerful tool for studying the structural changes that occur in biological molecules under different conditions, such as temperature, pH, or the presence of ligands or other molecules. It can also be used to monitor the folding and unfolding of proteins, as well as the binding of drugs or other small molecules to their targets.

Gramicidin is not a medical condition but rather an antibiotic substance that is used in medical treatments.

Here's the scientific and pharmacological definition:

Gramicidin is a narrow-spectrum, cationic antimicrobial peptide derived from gram-positive bacteria of the genus Bacillus. It is an ionophore that selectively binds to monovalent cations, forming channels in lipid bilayers and causing disruption of bacterial cell membranes, leading to bacterial lysis and death. Gramicidin D, a mixture of at least four different gramicidins (A, B, C, and D), is commonly used in topical formulations for the treatment of skin and eye infections due to its potent antimicrobial activity against many gram-positive and some gram-negative bacteria. However, it has limited systemic use due to its potential toxicity to mammalian cells.

Polyethylene glycols (PEGs) are a family of synthetic, water-soluble polymers with a wide range of molecular weights. They are commonly used in the medical field as excipients in pharmaceutical formulations due to their ability to improve drug solubility, stability, and bioavailability. PEGs can also be used as laxatives to treat constipation or as bowel cleansing agents prior to colonoscopy examinations. Additionally, some PEG-conjugated drugs have been developed for use in targeted cancer therapies.

In a medical context, PEGs are often referred to by their average molecular weight, such as PEG 300, PEG 400, PEG 1500, and so on. Higher molecular weight PEGs tend to be more viscous and have longer-lasting effects in the body.

It's worth noting that while PEGs are generally considered safe for use in medical applications, some people may experience allergic reactions or hypersensitivity to these compounds. Prolonged exposure to high molecular weight PEGs has also been linked to potential adverse effects, such as decreased fertility and developmental toxicity in animal studies. However, more research is needed to fully understand the long-term safety of PEGs in humans.

Factor X is a protein that is essential for blood clotting, also known as coagulation. It is an enzyme that plays a crucial role in the coagulation cascade, which is a series of chemical reactions that lead to the formation of a blood clot. Factor X is activated by one of two pathways: the intrinsic pathway, which is initiated by damage to the blood vessels, or the extrinsic pathway, which is triggered by the release of tissue factor from damaged cells. Once activated, Factor X converts prothrombin to thrombin, which then converts fibrinogen to fibrin to form a stable clot.

Inherited deficiencies in Factor X can lead to bleeding disorders, while increased levels of Factor X have been associated with an increased risk of thrombosis or blood clots. Therefore, maintaining appropriate levels of Factor X is important for the proper balance between bleeding and clotting in the body.

The egg yolk is the nutrient-rich, inner portion of an egg that is surrounded by a protective layer of egg white. It is typically yellowish-orange and has a creamy consistency. The egg yolk contains various essential nutrients such as proteins, fats, vitamins (like A, D, E, and K), minerals (such as calcium, phosphorus, zinc, and iron), and antioxidants (like lutein and zeaxanthin). It is also a significant source of cholesterol. The egg yolk plays an essential role in the development of embryos in birds and reptiles, providing them with necessary nutrients for growth and energy. In culinary applications, egg yolks are often used as emulsifiers, thickeners, and leavening agents in various dishes.

Adsorption is a process in which atoms, ions, or molecules from a gas, liquid, or dissolved solid accumulate on the surface of a material. This occurs because the particles in the adsorbate (the substance being adsorbed) have forces that attract them to the surface of the adsorbent (the material that the adsorbate is adhering to).

In medical terms, adsorption can refer to the use of materials with adsorptive properties to remove harmful substances from the body. For example, activated charcoal is sometimes used in the treatment of poisoning because it can adsorb a variety of toxic substances and prevent them from being absorbed into the bloodstream.

It's important to note that adsorption is different from absorption, which refers to the process by which a substance is taken up and distributed throughout a material or tissue.

Apolipoproteins are a group of proteins that are associated with lipids (fats) in the body and play a crucial role in the metabolism, transportation, and regulation of lipids. They are structural components of lipoprotein particles, which are complexes of lipids and proteins that transport lipids in the bloodstream.

There are several types of apolipoproteins, including ApoA, ApoB, ApoC, ApoD, ApoE, and others. Each type has a specific function in lipid metabolism. For example, ApoA is a major component of high-density lipoprotein (HDL), often referred to as "good cholesterol," and helps remove excess cholesterol from cells and tissues and transport it to the liver for excretion. ApoB, on the other hand, is a major component of low-density lipoprotein (LDL), or "bad cholesterol," and plays a role in the delivery of cholesterol to cells and tissues.

Abnormal levels of apolipoproteins or dysfunctional forms of these proteins have been linked to various diseases, including cardiovascular disease, Alzheimer's disease, and metabolic disorders such as diabetes. Therefore, measuring apolipoprotein levels in the blood can provide valuable information for diagnosing and monitoring these conditions.

Secondary protein structure refers to the local spatial arrangement of amino acid chains in a protein, typically described as regular repeating patterns held together by hydrogen bonds. The two most common types of secondary structures are the alpha-helix (α-helix) and the beta-pleated sheet (β-sheet). In an α-helix, the polypeptide chain twists around itself in a helical shape, with each backbone atom forming a hydrogen bond with the fourth amino acid residue along the chain. This forms a rigid rod-like structure that is resistant to bending or twisting forces. In β-sheets, adjacent segments of the polypeptide chain run parallel or antiparallel to each other and are connected by hydrogen bonds, forming a pleated sheet-like arrangement. These secondary structures provide the foundation for the formation of tertiary and quaternary protein structures, which determine the overall three-dimensional shape and function of the protein.

2-Naphthylamine is a crystalline solid organic compound that is classified as a primary aromatic amine. Its chemical formula is C10H9N. It is an intensely orange-red to reddish-brown substance that is slightly soluble in water and more soluble in organic solvents.

2-Naphthylamine is produced by the reduction of 2-naphthol or its derivatives. Historically, it was used as an intermediate in the synthesis of azo dyes and other chemical compounds. However, due to its toxicity and carcinogenicity, its use has been largely discontinued in many industries.

Exposure to 2-Naphthylamine can occur through inhalation, skin contact, or ingestion, and it has been associated with an increased risk of bladder cancer and other health effects. Therefore, appropriate safety measures must be taken when handling this compound, including the use of personal protective equipment (PPE) such as gloves, lab coats, and eye protection.

Fish oils are a type of fat or lipid derived from the tissues of oily fish. They are a rich source of omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These fatty acids have been associated with various health benefits such as reducing inflammation, decreasing the risk of heart disease, improving brain function, and promoting eye health. Fish oils can be consumed through diet or taken as a dietary supplement in the form of capsules or liquid. It is important to note that while fish oils have potential health benefits, they should not replace a balanced diet and medical advice should be sought before starting any supplementation.

Mass spectrometry with electrospray ionization (ESI-MS) is an analytical technique used to identify and quantify chemical species in a sample based on the mass-to-charge ratio of charged particles. In ESI-MS, analytes are ionized through the use of an electrospray, where a liquid sample is introduced through a metal capillary needle at high voltage, creating an aerosol of charged droplets. As the solvent evaporates, the analyte molecules become charged and can be directed into a mass spectrometer for analysis.

ESI-MS is particularly useful for the analysis of large biomolecules such as proteins, peptides, and nucleic acids, due to its ability to gently ionize these species without fragmentation. The technique provides information about the molecular weight and charge state of the analytes, which can be used to infer their identity and structure. Additionally, ESI-MS can be interfaced with separation techniques such as liquid chromatography (LC) for further purification and characterization of complex samples.

Protein conformation refers to the specific three-dimensional shape that a protein molecule assumes due to the spatial arrangement of its constituent amino acid residues and their associated chemical groups. This complex structure is determined by several factors, including covalent bonds (disulfide bridges), hydrogen bonds, van der Waals forces, and ionic bonds, which help stabilize the protein's unique conformation.

Protein conformations can be broadly classified into two categories: primary, secondary, tertiary, and quaternary structures. The primary structure represents the linear sequence of amino acids in a polypeptide chain. The secondary structure arises from local interactions between adjacent amino acid residues, leading to the formation of recurring motifs such as α-helices and β-sheets. Tertiary structure refers to the overall three-dimensional folding pattern of a single polypeptide chain, while quaternary structure describes the spatial arrangement of multiple folded polypeptide chains (subunits) that interact to form a functional protein complex.

Understanding protein conformation is crucial for elucidating protein function, as the specific three-dimensional shape of a protein directly influences its ability to interact with other molecules, such as ligands, nucleic acids, or other proteins. Any alterations in protein conformation due to genetic mutations, environmental factors, or chemical modifications can lead to loss of function, misfolding, aggregation, and disease states like neurodegenerative disorders and cancer.

Recombinant proteins are artificially created proteins produced through the use of recombinant DNA technology. This process involves combining DNA molecules from different sources to create a new set of genes that encode for a specific protein. The resulting recombinant protein can then be expressed, purified, and used for various applications in research, medicine, and industry.

Recombinant proteins are widely used in biomedical research to study protein function, structure, and interactions. They are also used in the development of diagnostic tests, vaccines, and therapeutic drugs. For example, recombinant insulin is a common treatment for diabetes, while recombinant human growth hormone is used to treat growth disorders.

The production of recombinant proteins typically involves the use of host cells, such as bacteria, yeast, or mammalian cells, which are engineered to express the desired protein. The host cells are transformed with a plasmid vector containing the gene of interest, along with regulatory elements that control its expression. Once the host cells are cultured and the protein is expressed, it can be purified using various chromatography techniques.

Overall, recombinant proteins have revolutionized many areas of biology and medicine, enabling researchers to study and manipulate proteins in ways that were previously impossible.

Pulmonary surfactant-associated proteins are a group of proteins that are found in the pulmonary surfactant, a complex mixture of lipids and proteins that coats the inside surfaces of the alveoli in the lungs. The primary function of pulmonary surfactant is to reduce the surface tension at the air-liquid interface in the alveoli, which facilitates breathing by preventing collapse of the alveoli during expiration.

There are four main pulmonary surfactant-associated proteins, designated as SP-A, SP-B, SP-C, and SP-D. These proteins play important roles in maintaining the stability and function of the pulmonary surfactant film, as well as participating in host defense mechanisms in the lungs.

SP-A and SP-D are members of the collectin family of proteins and have been shown to have immunomodulatory functions, including binding to pathogens and modulating immune cell responses. SP-B and SP-C are hydrophobic proteins that play critical roles in reducing surface tension at the air-liquid interface and maintaining the stability of the surfactant film.

Deficiencies or dysfunction of pulmonary surfactant-associated proteins have been implicated in various lung diseases, including respiratory distress syndrome (RDS) in premature infants, chronic interstitial lung diseases, and pulmonary fibrosis.

1-Alkyl-2-acetylglycerophosphocholine esterase is an enzyme that hydrolyzes the ester bond in 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine (also known as platelet-activating factor, PAF), resulting in the production of 1-alkyl-2-lyso-sn-glycero-3-phosphocholine and acetate. This enzyme is involved in the regulation of PAF levels and thus plays a role in the modulation of various physiological processes, including inflammation and allergic responses.

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

Carbon isotopes are variants of the chemical element carbon that have different numbers of neutrons in their atomic nuclei. The most common and stable isotope of carbon is carbon-12 (^{12}C), which contains six protons and six neutrons. However, carbon can also come in other forms, known as isotopes, which contain different numbers of neutrons.

Carbon-13 (^{13}C) is a stable isotope of carbon that contains seven neutrons in its nucleus. It makes up about 1.1% of all carbon found on Earth and is used in various scientific applications, such as in tracing the metabolic pathways of organisms or in studying the age of fossilized materials.

Carbon-14 (^{14}C), also known as radiocarbon, is a radioactive isotope of carbon that contains eight neutrons in its nucleus. It is produced naturally in the atmosphere through the interaction of cosmic rays with nitrogen gas. Carbon-14 has a half-life of about 5,730 years, which makes it useful for dating organic materials, such as archaeological artifacts or fossils, up to around 60,000 years old.

Carbon isotopes are important in many scientific fields, including geology, biology, and medicine, and are used in a variety of applications, from studying the Earth's climate history to diagnosing medical conditions.

Lipid peroxides are chemical compounds that form when lipids (fats or fat-like substances) oxidize. This process, known as lipid peroxidation, involves the reaction of lipids with oxygen in a way that leads to the formation of hydroperoxides and various aldehydes, such as malondialdehyde.

Lipid peroxidation is a naturally occurring process that can also be accelerated by factors such as exposure to radiation, certain chemicals, or enzymatic reactions. It plays a role in many biological processes, including cell signaling and regulation of gene expression, but it can also contribute to the development of various diseases when it becomes excessive.

Examples of lipid peroxides include phospholipid hydroperoxides, cholesteryl ester hydroperoxides, and triglyceride hydroperoxides. These compounds are often used as markers of oxidative stress in biological systems and have been implicated in the pathogenesis of atherosclerosis, cancer, neurodegenerative diseases, and other conditions associated with oxidative damage.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

Electrophoresis, polyacrylamide gel (EPG) is a laboratory technique used to separate and analyze complex mixtures of proteins or nucleic acids (DNA or RNA) based on their size and electrical charge. This technique utilizes a matrix made of cross-linked polyacrylamide, a type of gel, which provides a stable and uniform environment for the separation of molecules.

In this process:

1. The polyacrylamide gel is prepared by mixing acrylamide monomers with a cross-linking agent (bis-acrylamide) and a catalyst (ammonium persulfate) in the presence of a buffer solution.
2. The gel is then poured into a mold and allowed to polymerize, forming a solid matrix with uniform pore sizes that depend on the concentration of acrylamide used. Higher concentrations result in smaller pores, providing better resolution for separating smaller molecules.
3. Once the gel has set, it is placed in an electrophoresis apparatus containing a buffer solution. Samples containing the mixture of proteins or nucleic acids are loaded into wells on the top of the gel.
4. An electric field is applied across the gel, causing the negatively charged molecules to migrate towards the positive electrode (anode) while positively charged molecules move toward the negative electrode (cathode). The rate of migration depends on the size, charge, and shape of the molecules.
5. Smaller molecules move faster through the gel matrix and will migrate farther from the origin compared to larger molecules, resulting in separation based on size. Proteins and nucleic acids can be selectively stained after electrophoresis to visualize the separated bands.

EPG is widely used in various research fields, including molecular biology, genetics, proteomics, and forensic science, for applications such as protein characterization, DNA fragment analysis, cloning, mutation detection, and quality control of nucleic acid or protein samples.

Paper chromatography is a type of chromatography technique that involves the separation and analysis of mixtures based on their components' ability to migrate differently upon capillary action on a paper medium. This simple and cost-effective method utilizes a paper, typically made of cellulose, as the stationary phase. The sample mixture is applied as a small spot near one end of the paper, and then the other end is dipped into a developing solvent or a mixture of solvents (mobile phase) in a shallow container.

As the mobile phase moves up the paper by capillary action, components within the sample mixture separate based on their partition coefficients between the stationary and mobile phases. The partition coefficient describes how much a component prefers to be in either the stationary or mobile phase. Components with higher partition coefficients in the mobile phase will move faster and further than those with lower partition coefficients.

Once separation is complete, the paper is dried and can be visualized under ultraviolet light or by using chemical reagents specific for the components of interest. The distance each component travels from the origin (point of application) and its corresponding solvent front position are measured, allowing for the calculation of Rf values (retardation factors). Rf is a dimensionless quantity calculated as the ratio of the distance traveled by the component to the distance traveled by the solvent front.

Rf = (distance traveled by component) / (distance traveled by solvent front)

Paper chromatography has been widely used in various applications, such as:

1. Identification and purity analysis of chemical compounds in pharmaceuticals, forensics, and research laboratories.
2. Separation and detection of amino acids, sugars, and other biomolecules in biological samples.
3. Educational purposes to demonstrate the principles of chromatography and separation techniques.

Despite its limitations, such as lower resolution compared to high-performance liquid chromatography (HPLC) and less compatibility with volatile or nonpolar compounds, paper chromatography remains a valuable tool for quick, qualitative analysis in various fields.

Myo-Inositol-1-Phosphate Synthase (MIPS) is an enzyme that catalyzes the conversion of glucose-6-phosphate to inositol 1,4-bisphosphate, which is the first and rate-limiting step in the biosynthesis of myo-inositol. Myo-inositol is a six-carbon cyclic polyol that serves as a precursor for various secondary messengers and structural lipids, including phosphatidylinositols and inositol phosphates, which play crucial roles in cell signaling pathways.

MIPS is widely distributed in nature and has been identified in bacteria, plants, fungi, and animals. In humans, MIPS is encoded by the ISO1 gene and is primarily localized in the cytoplasm of cells. Defects in MIPS have been associated with several diseases, including neurological disorders and cancer, highlighting its importance in maintaining cellular homeostasis.

Lipid peroxidation is a process in which free radicals, such as reactive oxygen species (ROS), steal electrons from lipids containing carbon-carbon double bonds, particularly polyunsaturated fatty acids (PUFAs). This results in the formation of lipid hydroperoxides, which can decompose to form a variety of compounds including reactive carbonyl compounds, aldehydes, and ketones.

Malondialdehyde (MDA) is one such compound that is commonly used as a marker for lipid peroxidation. Lipid peroxidation can cause damage to cell membranes, leading to changes in their fluidity and permeability, and can also result in the modification of proteins and DNA, contributing to cellular dysfunction and ultimately cell death. It is associated with various pathological conditions such as atherosclerosis, neurodegenerative diseases, and cancer.

Blood platelets, also known as thrombocytes, are small, colorless cell fragments in our blood that play an essential role in normal blood clotting. They are formed in the bone marrow from large cells called megakaryocytes and circulate in the blood in an inactive state until they are needed to help stop bleeding. When a blood vessel is damaged, platelets become activated and change shape, releasing chemicals that attract more platelets to the site of injury. These activated platelets then stick together to form a plug, or clot, that seals the wound and prevents further blood loss. In addition to their role in clotting, platelets also help to promote healing by releasing growth factors that stimulate the growth of new tissue.

Microsomes, liver refers to a subcellular fraction of liver cells (hepatocytes) that are obtained during tissue homogenization and subsequent centrifugation. These microsomal fractions are rich in membranous structures known as the endoplasmic reticulum (ER), particularly the rough ER. They are involved in various important cellular processes, most notably the metabolism of xenobiotics (foreign substances) including drugs, toxins, and carcinogens.

The liver microsomes contain a variety of enzymes, such as cytochrome P450 monooxygenases, that are crucial for phase I drug metabolism. These enzymes help in the oxidation, reduction, or hydrolysis of xenobiotics, making them more water-soluble and facilitating their excretion from the body. Additionally, liver microsomes also host other enzymes involved in phase II conjugation reactions, where the metabolites from phase I are further modified by adding polar molecules like glucuronic acid, sulfate, or acetyl groups.

In summary, liver microsomes are a subcellular fraction of liver cells that play a significant role in the metabolism and detoxification of xenobiotics, contributing to the overall protection and maintenance of cellular homeostasis within the body.

Palmitic acid is a type of saturated fatty acid, which is a common component in many foods and also produced naturally by the human body. Its chemical formula is C16H32O2. It's named after palm trees because it was first isolated from palm oil, although it can also be found in other vegetable oils, animal fats, and dairy products.

In the human body, palmitic acid plays a role in energy production and storage. However, consuming large amounts of this fatty acid has been linked to an increased risk of heart disease due to its association with elevated levels of bad cholesterol (LDL). The World Health Organization recommends limiting the consumption of saturated fats, including palmitic acid, to less than 10% of total energy intake.

Factor Xa is a serine protease that plays a crucial role in the coagulation cascade, which is a series of reactions that lead to the formation of a blood clot. It is one of the activated forms of Factor X, a pro-protein that is converted to Factor Xa through the action of other enzymes in the coagulation cascade.

Factor Xa functions as a key component of the prothrombinase complex, which also includes calcium ions, phospholipids, and activated Factor V (also known as Activated Protein C or APC). This complex is responsible for converting prothrombin to thrombin, which then converts fibrinogen to fibrin, forming a stable clot.

Inhibitors of Factor Xa are used as anticoagulants in the prevention and treatment of thromboembolic disorders such as deep vein thrombosis and pulmonary embolism. These drugs work by selectively inhibiting Factor Xa, thereby preventing the formation of the prothrombinase complex and reducing the risk of clot formation.

Medical Definition of Monoglycerides:

Monoglycerides are types of glycerides that contain one molecule of fatty acid combined with a glycerol molecule through an ester linkage. They are often used as food additives, serving as emulsifiers to help blend together water and oil-based ingredients in foods such as baked goods, ice cream, and chocolate. Monoglycerides can also be found naturally in some foods, including certain vegetable oils.

In the context of human physiology, monoglycerides can serve as a source of energy and can also play a role in the absorption and transport of fatty acids in the body. However, they are not typically considered to be a major nutrient or component of the human diet.

Tertiary protein structure refers to the three-dimensional arrangement of all the elements (polypeptide chains) of a single protein molecule. It is the highest level of structural organization and results from interactions between various side chains (R groups) of the amino acids that make up the protein. These interactions, which include hydrogen bonds, ionic bonds, van der Waals forces, and disulfide bridges, give the protein its unique shape and stability, which in turn determines its function. The tertiary structure of a protein can be stabilized by various factors such as temperature, pH, and the presence of certain ions. Any changes in these factors can lead to denaturation, where the protein loses its tertiary structure and thus its function.

Nonesterified fatty acids (NEFA), also known as free fatty acids (FFA), refer to fatty acid molecules that are not bound to glycerol in the form of triglycerides or other esters. In the bloodstream, NEFAs are transported while bound to albumin and can serve as a source of energy for peripheral tissues. Under normal physiological conditions, NEFA levels are tightly regulated by the body; however, elevated NEFA levels have been associated with various metabolic disorders such as insulin resistance, obesity, and type 2 diabetes.

"Saccharomyces cerevisiae" is not typically considered a medical term, but it is a scientific name used in the field of microbiology. It refers to a species of yeast that is commonly used in various industrial processes, such as baking and brewing. It's also widely used in scientific research due to its genetic tractability and eukaryotic cellular organization.

However, it does have some relevance to medical fields like medicine and nutrition. For example, certain strains of S. cerevisiae are used as probiotics, which can provide health benefits when consumed. They may help support gut health, enhance the immune system, and even assist in the digestion of certain nutrients.

In summary, "Saccharomyces cerevisiae" is a species of yeast with various industrial and potential medical applications.

Choline-phosphate cytidylyltransferase is an enzyme that plays a crucial role in the synthesis of phosphatidylcholine, a major component of cell membranes. This enzyme catalyzes the reaction between cytidine triphosphate (CTP) and phosphocholine to produce cytidine diphosphate-choline (CDP-choline), which is then used to synthesize phosphatidylcholine.

The enzyme exists in two forms: an inner mitochondrial membrane-bound form (CM-ChoCT) and an endoplasmic reticulum/nuclear envelope-associated form (ER-ChoCT). These two forms have different regulatory mechanisms and functions, with CM-ChoCT being responsible for the majority of CDP-choline production in the liver.

Deficiencies or mutations in choline-phosphate cytidylyltransferase can lead to a variety of health issues, including fatty liver disease, muscle damage, and neurological disorders. Proper regulation and function of this enzyme are essential for maintaining cell membrane integrity and overall health.

Group VI Phospholipases A2 (PLA2) are a subclass of the PLA2 family, which are enzymes that hydrolyze the sn-2 ester bond of glycerophospholipids to release free fatty acids and lysophospholipids. Specifically, Group VI PLA2s are calcium-dependent enzymes that have been identified in various tissues, including the brain and testis. They play important roles in several biological processes, such as cell signaling, inflammation, and lipid metabolism.

Group VI PLA2s are further divided into two subgroups: Group VI A and Group VI B. The Group VI A subgroup includes the iPLA2-VIA (also known as PLA2G6) enzyme, which has been implicated in several neurological disorders, such as neurodegenerative diseases and hereditary spastic paraplegia. On the other hand, the Group VI B subgroup includes the pancreatic-type PLA2 (also known as PLA2G1B) enzyme, which is primarily involved in digestion.

It's worth noting that while Group VI PLA2s have important physiological functions, they can also contribute to pathological conditions when their activity is dysregulated. For example, excessive activation of these enzymes has been linked to the development and progression of various inflammatory diseases, such as atherosclerosis, arthritis, and asthma.

Dietary fats, also known as fatty acids, are a major nutrient that the body needs for energy and various functions. They are an essential component of cell membranes and hormones, and they help the body absorb certain vitamins. There are several types of dietary fats:

1. Saturated fats: These are typically solid at room temperature and are found in animal products such as meat, butter, and cheese, as well as tropical oils like coconut and palm oil. Consuming a high amount of saturated fats can raise levels of unhealthy LDL cholesterol and increase the risk of heart disease.
2. Unsaturated fats: These are typically liquid at room temperature and can be further divided into monounsaturated and polyunsaturated fats. Monounsaturated fats, found in foods such as olive oil, avocados, and nuts, can help lower levels of unhealthy LDL cholesterol while maintaining levels of healthy HDL cholesterol. Polyunsaturated fats, found in foods such as fatty fish, flaxseeds, and walnuts, have similar effects on cholesterol levels and also provide essential omega-3 and omega-6 fatty acids that the body cannot produce on its own.
3. Trans fats: These are unsaturated fats that have been chemically modified to be solid at room temperature. They are often found in processed foods such as baked goods, fried foods, and snack foods. Consuming trans fats can raise levels of unhealthy LDL cholesterol and lower levels of healthy HDL cholesterol, increasing the risk of heart disease.

It is recommended to limit intake of saturated and trans fats and to consume more unsaturated fats as part of a healthy diet.

Mass spectrometry (MS) is an analytical technique used to identify and quantify the chemical components of a mixture or compound. It works by ionizing the sample, generating charged molecules or fragments, and then measuring their mass-to-charge ratio in a vacuum. The resulting mass spectrum provides information about the molecular weight and structure of the analytes, allowing for identification and characterization.

In simpler terms, mass spectrometry is a method used to determine what chemicals are present in a sample and in what quantities, by converting the chemicals into ions, measuring their masses, and generating a spectrum that shows the relative abundances of each ion type.

Freeze fracturing is not a medical term itself, but it is a technique used in the field of electron microscopy, which is a type of imaging commonly used in scientific research and medical fields to visualize structures at a very small scale, such as cells and cellular components.

In freeze fracturing, a sample is rapidly frozen to preserve its structure and then fractured or split along a plane of weakness, often along the membrane of a cell. The freshly exposed surface is then shadowed with a thin layer of metal, such as platinum or gold, to create a replica of the surface. This replica can then be examined using an electron microscope to reveal details about the structure and organization of the sample at the molecular level.

Freeze fracturing is particularly useful for studying membrane structures, such as lipid bilayers and protein complexes, because it allows researchers to visualize these structures in their native state, without the need for staining or other chemical treatments that can alter or damage the samples.

Electron Spin Resonance (ESR) Spectroscopy, also known as Electron Paramagnetic Resonance (EPR) Spectroscopy, is a technique used to investigate materials with unpaired electrons. It is based on the principle of absorption of energy by the unpaired electrons when they are exposed to an external magnetic field and microwave radiation.

In this technique, a sample is placed in a magnetic field and microwave radiation is applied. The unpaired electrons in the sample absorb energy and change their spin state when the energy of the microwaves matches the energy difference between the spin states. This absorption of energy is recorded as a function of the magnetic field strength, producing an ESR spectrum.

ESR spectroscopy can provide information about the number, type, and behavior of unpaired electrons in a sample, as well as the local environment around the electron. It is widely used in physics, chemistry, and biology to study materials such as free radicals, transition metal ions, and defects in solids.

Pulmonary Surfactant-Associated Protein A (SP-A) is a protein that is a major component of pulmonary surfactant, which is a complex mixture of lipids and proteins found in the alveoli of the lungs. SP-A is produced by specialized cells called type II alveolar epithelial cells and has several important functions in the lung.

SP-A plays a role in innate immunity by binding to pathogens, such as bacteria and viruses, and facilitating their clearance from the lungs. It also helps to regulate surfactant homeostasis by participating in the reuptake and recycling of surfactant components. Additionally, SP-A has been shown to have anti-inflammatory effects and may help to modulate the immune response in the lung.

Deficiencies or mutations in SP-A have been associated with various respiratory diseases, including acute respiratory distress syndrome (ARDS), pulmonary fibrosis, and chronic obstructive pulmonary disease (COPD).

Lysophospholipase is an enzyme that catalyzes the hydrolysis of a single fatty acid from lysophospholipids, producing a glycerophosphocholine and free fatty acid. This enzyme plays a role in the metabolism of lipids and membrane homeostasis. There are several types of lysophospholipases that differ based on their specificity for the head group of the lysophospholipid substrate, such as lysophosphatidylcholine-specific phospholipase or lysophospholipase 1 (LPLA1), and lysophosphatidic acid-specific phospholipase D or autotaxin (ATX).

Deficiency or mutations in lysophospholipases can lead to various diseases, such as LPI (lysophosphatidylinositol lipidosis) caused by a deficiency of the lysophospholipase superfamily member called Ptdlns-specific phospholipase C (PLC).

Note: This definition is for general information purposes only and may not include all the latest findings or medical terminologies. For accurate and comprehensive understanding, it's recommended to consult authoritative medical textbooks or resources.

Triolein is a type of triglyceride, which is a kind of fat molecule. More specifically, triolein is the triglyceride formed from three molecules of oleic acid, a common monounsaturated fatty acid. It is often used in scientific research and studies involving lipid metabolism, and it can be found in various vegetable oils and animal fats.

Stearic acid is not typically considered a medical term, but rather a chemical compound. It is a saturated fatty acid with the chemical formula C18H36O2. Stearic acid is commonly found in various foods such as animal fats and vegetable oils, including cocoa butter and palm oil.

In a medical context, stearic acid might be mentioned in relation to nutrition or cosmetics. For example, it may be listed as an ingredient in some skincare products or medications where it is used as an emollient or thickening agent. It's also worth noting that while stearic acid is a saturated fat, some studies suggest that it may have a more neutral effect on blood cholesterol levels compared to other saturated fats. However, this is still a topic of ongoing research and debate in the medical community.

Alpha-linolenic acid (ALA) is a type of essential fatty acid, which means that it cannot be produced by the human body and must be obtained through diet. It is an 18-carbon fatty acid with three cis double bonds, and its chemical formula is C18:3 n-3 or 9c,12c,15c-18:3.

ALA is one of the two essential omega-3 fatty acids, along with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). ALA is found in a variety of plant sources, including flaxseeds, chia seeds, hemp seeds, walnuts, soybeans, and some vegetable oils such as canola and soybean oil.

ALA is an important precursor to EPA and DHA, which have been shown to have numerous health benefits, including reducing inflammation, improving heart health, and supporting brain function. However, the conversion of ALA to EPA and DHA is limited in humans, and it is recommended to consume foods rich in EPA and DHA directly, such as fatty fish and fish oil supplements.

Medically speaking, a deficiency in ALA can lead to various health issues, including dry skin, hair loss, poor wound healing, and increased risk of heart disease. Therefore, it is important to include adequate amounts of ALA-rich foods in the diet to maintain optimal health.

Cholic acids are a type of bile acid, which are naturally occurring steroid acids that play a crucial role in the digestion and absorption of fats and fat-soluble vitamins in the body. Cholic acid is the primary bile acid synthesized in the liver from cholesterol. It is then conjugated with glycine or taurine to form conjugated cholic acids, which are stored in the gallbladder and released into the small intestine during digestion to aid in fat emulsification and absorption.

Cholic acid and its derivatives have also been studied for their potential therapeutic benefits in various medical conditions, including liver diseases, gallstones, and bacterial infections. However, more research is needed to fully understand the mechanisms of action and potential side effects of cholic acids and their derivatives before they can be widely used as therapeutic agents.

Lipidoses are a group of genetic disorders characterized by abnormal accumulation of lipids (fats or fat-like substances) in various tissues and cells of the body due to defects in lipid metabolism. These disorders include conditions such as Gaucher's disease, Tay-Sachs disease, Niemann-Pick disease, Fabry disease, and Wolman disease, among others. The accumulation of lipids can lead to progressive damage in multiple organs, resulting in a range of symptoms and health complications. Early diagnosis and management are essential for improving the quality of life and prognosis of affected individuals.

Glycoproteins are complex proteins that contain oligosaccharide chains (glycans) covalently attached to their polypeptide backbone. These glycans are linked to the protein through asparagine residues (N-linked) or serine/threonine residues (O-linked). Glycoproteins play crucial roles in various biological processes, including cell recognition, cell-cell interactions, cell adhesion, and signal transduction. They are widely distributed in nature and can be found on the outer surface of cell membranes, in extracellular fluids, and as components of the extracellular matrix. The structure and composition of glycoproteins can vary significantly depending on their function and location within an organism.

Ethanolaminephosphotransferase is an enzyme that plays a role in the biosynthesis of phosphatidylethanolamine, which is a type of phospholipid found in biological membranes. Phosphatidylethanolamine is an essential component of cell membranes and is involved in various cellular processes, including signal transduction and membrane trafficking.

Ethanolaminephosphotrtransferase catalyzes the transfer of a phosphoethanolamine group from CDP-ethanolamine to the hydroxyl group of diacylglycerol (DAG), resulting in the formation of phosphatidylethanolamine. This enzyme is widely distributed in nature and is found in various organisms, including bacteria, plants, and animals.

Defects in ethanolaminephosphotransferase have been associated with certain genetic disorders, such as congenital disorder of glycosylation type Ia (CDG-Ia) and autosomal recessive intellectual disability syndrome 26 (ARID26). These disorders can result in a range of symptoms, including developmental delays, seizures, and movement disorders.

"Swine" is a common term used to refer to even-toed ungulates of the family Suidae, including domestic pigs and wild boars. However, in a medical context, "swine" often appears in the phrase "swine flu," which is a strain of influenza virus that typically infects pigs but can also cause illness in humans. The 2009 H1N1 pandemic was caused by a new strain of swine-origin influenza A virus, which was commonly referred to as "swine flu." It's important to note that this virus is not transmitted through eating cooked pork products; it spreads from person to person, mainly through respiratory droplets produced when an infected person coughs or sneezes.

Bile acids and salts are naturally occurring steroidal compounds that play a crucial role in the digestion and absorption of lipids (fats) in the body. They are produced in the liver from cholesterol and then conjugated with glycine or taurine to form bile acids, which are subsequently converted into bile salts by the addition of a sodium or potassium ion.

Bile acids and salts are stored in the gallbladder and released into the small intestine during digestion, where they help emulsify fats, allowing them to be broken down into smaller molecules that can be absorbed by the body. They also aid in the elimination of waste products from the liver and help regulate cholesterol metabolism.

Abnormalities in bile acid synthesis or transport can lead to various medical conditions, such as cholestatic liver diseases, gallstones, and diarrhea. Therefore, understanding the role of bile acids and salts in the body is essential for diagnosing and treating these disorders.

I'm sorry for any confusion, but static electricity is not a term that has a specific medical definition. Static electricity is an electrical charge that builds up on the surface of objects. This occurs when there is an imbalance of electric charges within or on the surface of a material. It can be caused by certain conditions, such as friction, which can build up an electric charge.

While not a medical term, static electricity can have various effects in different settings, including medical ones. For instance, it can cause issues with electronic equipment used in healthcare settings. Additionally, some people may experience a shock or spark when they touch a conductive object that has been charged with static electricity. However, these occurrences are not typically considered medical conditions or issues.

Peptides are short chains of amino acid residues linked by covalent bonds, known as peptide bonds. They are formed when two or more amino acids are joined together through a condensation reaction, which results in the elimination of a water molecule and the formation of an amide bond between the carboxyl group of one amino acid and the amino group of another.

Peptides can vary in length from two to about fifty amino acids, and they are often classified based on their size. For example, dipeptides contain two amino acids, tripeptides contain three, and so on. Oligopeptides typically contain up to ten amino acids, while polypeptides can contain dozens or even hundreds of amino acids.

Peptides play many important roles in the body, including serving as hormones, neurotransmitters, enzymes, and antibiotics. They are also used in medical research and therapeutic applications, such as drug delivery and tissue engineering.

Cell membrane permeability refers to the ability of various substances, such as molecules and ions, to pass through the cell membrane. The cell membrane, also known as the plasma membrane, is a thin, flexible barrier that surrounds all cells, controlling what enters and leaves the cell. Its primary function is to protect the cell's internal environment and maintain homeostasis.

The permeability of the cell membrane depends on its structure, which consists of a phospholipid bilayer interspersed with proteins. The hydrophilic (water-loving) heads of the phospholipids face outward, while the hydrophobic (water-fearing) tails face inward, creating a barrier that is generally impermeable to large, polar, or charged molecules.

However, specific proteins within the membrane, called channels and transporters, allow certain substances to cross the membrane. Channels are protein structures that span the membrane and provide a pore for ions or small uncharged molecules to pass through. Transporters, on the other hand, are proteins that bind to specific molecules and facilitate their movement across the membrane, often using energy in the form of ATP.

The permeability of the cell membrane can be influenced by various factors, such as temperature, pH, and the presence of certain chemicals or drugs. Changes in permeability can have significant consequences for the cell's function and survival, as they can disrupt ion balances, nutrient uptake, waste removal, and signal transduction.

Esters are organic compounds that are formed by the reaction between an alcohol and a carboxylic acid. They are widely found in nature and are used in various industries, including the production of perfumes, flavors, and pharmaceuticals. In the context of medical definitions, esters may be mentioned in relation to their use as excipients in medications or in discussions of organic chemistry and biochemistry. Esters can also be found in various natural substances such as fats and oils, which are triesters of glycerol and fatty acids.

Unithiol is the common name for the drug compound mercaptopropionylglycine (MPG). It is a synthetic aminocarboxylic acid that acts as a chelating agent, binding to heavy metals in the body and facilitating their elimination. Unithiol has been used in the treatment of various conditions associated with heavy metal toxicity, such as Wilson's disease, lead poisoning, and mercury poisoning. It is also known for its potential use in protecting against chemotherapy-induced peripheral neuropathy.

In medical terms, Unithiol can be defined as:

A synthetic chelating agent with the chemical formula C5H9NO3S, used in the treatment of heavy metal poisoning to promote the excretion of toxic metals from the body. It is administered orally and works by forming stable complexes with heavy metals, which are then eliminated through urine. Unithiol has been found to be particularly effective in treating Wilson's disease, a genetic disorder that causes copper accumulation in various organs. Additionally, it may provide neuroprotective effects against chemotherapy-induced peripheral neuropathy.

Lipase is an enzyme that is produced by the pancreas and found in the digestive system of most organisms. Its primary function is to catalyze the hydrolysis of fats (triglycerides) into smaller molecules, such as fatty acids and glycerol, which can then be absorbed by the intestines and utilized for energy or stored for later use.

In medical terms, lipase levels in the blood are often measured to diagnose or monitor conditions that affect the pancreas, such as pancreatitis (inflammation of the pancreas), pancreatic cancer, or cystic fibrosis. Elevated lipase levels may indicate damage to the pancreas and its ability to produce digestive enzymes.

ATP-binding cassette (ABC) transporters are a family of membrane proteins that utilize the energy from ATP hydrolysis to transport various substrates across extra- and intracellular membranes. These transporters play crucial roles in several biological processes, including detoxification, drug resistance, nutrient uptake, and regulation of cellular cholesterol homeostasis.

The structure of ABC transporters consists of two nucleotide-binding domains (NBDs) that bind and hydrolyze ATP, and two transmembrane domains (TMDs) that form the substrate-translocation pathway. The NBDs are typically located adjacent to each other in the cytoplasm, while the TMDs can be either integral membrane domains or separate structures associated with the membrane.

The human genome encodes 48 distinct ABC transporters, which are classified into seven subfamilies (ABCA-ABCG) based on their sequence similarity and domain organization. Some well-known examples of ABC transporters include P-glycoprotein (ABCB1), multidrug resistance protein 1 (ABCC1), and breast cancer resistance protein (ABCG2).

Dysregulation or mutations in ABC transporters have been implicated in various diseases, such as cystic fibrosis, neurological disorders, and cancer. In cancer, overexpression of certain ABC transporters can contribute to drug resistance by actively effluxing chemotherapeutic agents from cancer cells, making them less susceptible to treatment.

Spectrophotometry, Infrared is a scientific analytical technique used to measure the absorption or transmission of infrared light by a sample. It involves the use of an infrared spectrophotometer, which directs infrared radiation through a sample and measures the intensity of the radiation that is transmitted or absorbed by the sample at different wavelengths within the infrared region of the electromagnetic spectrum.

Infrared spectroscopy can be used to identify and quantify functional groups and chemical bonds present in a sample, as well as to study the molecular structure and composition of materials. The resulting infrared spectrum provides a unique "fingerprint" of the sample, which can be compared with reference spectra to aid in identification and characterization.

Infrared spectrophotometry is widely used in various fields such as chemistry, biology, pharmaceuticals, forensics, and materials science for qualitative and quantitative analysis of samples.

Gel chromatography is a type of liquid chromatography that separates molecules based on their size or molecular weight. It uses a stationary phase that consists of a gel matrix made up of cross-linked polymers, such as dextran, agarose, or polyacrylamide. The gel matrix contains pores of various sizes, which allow smaller molecules to penetrate deeper into the matrix while larger molecules are excluded.

In gel chromatography, a mixture of molecules is loaded onto the top of the gel column and eluted with a solvent that moves down the column by gravity or pressure. As the sample components move down the column, they interact with the gel matrix and get separated based on their size. Smaller molecules can enter the pores of the gel and take longer to elute, while larger molecules are excluded from the pores and elute more quickly.

Gel chromatography is commonly used to separate and purify proteins, nucleic acids, and other biomolecules based on their size and molecular weight. It is also used in the analysis of polymers, colloids, and other materials with a wide range of applications in chemistry, biology, and medicine.

Esterification is a chemical reaction that involves the conversion of an alcohol and a carboxylic acid into an ester, typically through the removal of a molecule of water. This reaction is often catalyzed by an acid or a base, and it is a key process in organic chemistry. Esters are commonly found in nature and are responsible for the fragrances of many fruits and flowers. They are also important in the production of various industrial and consumer products, including plastics, resins, and perfumes.

Phosphotransferases are a group of enzymes that catalyze the transfer of a phosphate group from a donor molecule to an acceptor molecule. This reaction is essential for various cellular processes, including energy metabolism, signal transduction, and biosynthesis.

The systematic name for this group of enzymes is phosphotransferase, which is derived from the general reaction they catalyze: D-donor + A-acceptor = D-donor minus phosphate + A-phosphate. The donor molecule can be a variety of compounds, such as ATP or a phosphorylated protein, while the acceptor molecule is typically a compound that becomes phosphorylated during the reaction.

Phosphotransferases are classified into several subgroups based on the type of donor and acceptor molecules they act upon. For example, kinases are a subgroup of phosphotransferases that transfer a phosphate group from ATP to a protein or other organic compound. Phosphatases, another subgroup, remove phosphate groups from molecules by transferring them to water.

Overall, phosphotransferases play a critical role in regulating many cellular functions and are important targets for drug development in various diseases, including cancer and neurological disorders.

PEG phospholipid (mPEG-phospholipid, polyglycerin-phospholipid, functionalized-phospholipid, terminal activated-phospholipid) ... The result is often a phospholipid bilayer: a membrane that consists of two layers of oppositely oriented phospholipid ... Liposomes are often composed of phosphatidylcholine-enriched phospholipids and may also contain mixed phospholipid chains with ... Phospholipids can act as emulsifiers, enabling oils to form a colloid with water. Phospholipids are one of the components of ...
This family contains acyltransferases involved in phospholipid biosynthesis and proteins of unknown function. This family also ...
Phospholipid+Scramblase at the U.S. National Library of Medicine Medical Subject Headings (MeSH) (CS1: long volume value, ... In humans, phospholipid scramblases (PLSCRs) constitute a family of five homologous proteins that are named as hPLSCR1-hPLSCR5 ... Phospholipid redistribution is triggered by increased cytosolic calcium and seems to be scramblase-dependent, resulting in a ... Phospholipid scramblase 1 (PLSCR1), a lipid-binding protein that enters the nucleus via the nonclassical NLS (257)GKISKHWTGI( ...
In enzymology, a phospholipid:diacylglycerol acyltransferase (EC 2.3.1.158) is an enzyme that catalyzes the chemical reaction ... The systematic name of this enzyme class is phospholipid:1,2-diacyl-sn-glycerol O-acyltransferase. This enzyme is also called ... Dahlqvist A, Stahl U, Lenman M, Banas A, Lee M, Sandager L, Ronne H, Stymne S (June 2000). "Phospholipid:diacylglycerol ... the two substrates of this enzyme are phospholipid and 1,2-diacylglycerol, whereas its two products are lysophospholipid and ...
... is a protein that in humans is encoded by the PLTP gene. The protein encoded by this gene is one ... "Entrez Gene: PLTP phospholipid transfer protein". Pussinen PJ, Jauhiainen M, Metso J, Pyle LE, Marcel YL, Fidge NH, Ehnholm C ( ... Pussinen PJ, Jauhiainen M, Metso J, Pyle LE, Marcel YL, Fidge NH, Ehnholm C (1998). "Binding of phospholipid transfer protein ( ... Jiang XC, D'Armiento J, Mallampalli RK, Mar J, Yan SF, Lin M (1998). "Expression of plasma phospholipid transfer protein mRNA ...
... may refer to: Methylene-fatty-acyl-phospholipid synthase Cyclopropane-fatty-acyl- ... phospholipid synthase This set index page lists enzyme articles associated with the same name. If an internal link led you here ...
... phospholipid out The 3 substrates of this enzyme are ATP, H2O, and phospholipid, whereas its 3 products are ADP, phosphate, and ... In enzymology, a phospholipid-translocating ATPase (EC 3.6.3.1) is an enzyme that catalyzes the chemical reaction ATP + H2O + ... Suzuki H, Kamakura M, Morii M, Takeguchi N (1997). "The phospholipid flippase activity of gastric vesicles". J. Biol. Chem. 272 ... The systematic name of this enzyme class is ATP phosphohydrolase (phospholipid-flipping). Other names in common use include ...
... product as plasma membrane phospholipid scramblase and chromosome mapping of the human MmTRA1b/phospholipid scramblase gene". ... Phospholipid scramblase 1 (PL scramblase 1) is an enzyme that in humans is encoded by the PLSCR1 gene. PLSCR1 has been shown to ... "Entrez Gene: PLSCR1 phospholipid scramblase 1". Rual JF, Venkatesan K, Hao T, Hirozane-Kishikawa T, Dricot A, Li N, Berriz GF, ... Zhou Q, Zhao J, Stout JG, Luhm RA, Wiedmer T, Sims PJ (August 1997). "Molecular cloning of human plasma membrane phospholipid ...
The phospholipid membrane systems are comparable to the model membranes above but it only consists of one phospholipid which is ... The phospholipid bilayer is a two-layer structure mainly composed of phospholipids, which are amphiphilic molecules that have ... Phospholipids consist of two non-polar hydrocarbon chains with ester or ether bonds to the phosphate group which is also linked ... The phospholipid carries a negative charge due to the presence of the phosphate group. Its overall polarity depends on the ...
... also known as ATPase class V type 10A or aminophospholipid translocase VA is an enzyme that ... "ATP10A - Phospholipid-transporting ATPase VA - Homo sapiens (Human) - ATP10A gene & protein". www.uniprot.org. Retrieved 9 ...
... phospholipid hydroperoxide-reducing), phospholipid hydroperoxide glutathione peroxidase, hydroperoxide glutathione peroxidase, ... In enzymology, a phospholipid-hydroperoxide glutathione peroxidase (EC 1.11.1.12) is an enzyme that catalyzes the chemical ... Ursini F, Maiorino M, Gregolin C (1985). "The selenoenzyme phospholipid hydroperoxide glutathione peroxidase". Biochim. Biophys ...
Probable phospholipid-transporting ATPase IC is an enzyme that in humans is encoded by the ATP8B1 gene. This protein is ...
Phospholipids can be saponified, which releases the fatty acids contained in their diglyceride tail. Once the phospholipids of ... phospholipids are rapidly degraded and the remaining phospholipid content of the sample is assumed to be from living organisms ... Phospholipids can occur in many biological classes (such as in plant roots, fungi, as well as in soil bacteria), so care has to ... However, as the phospholipids of archaea are not ester linked as in bacteria, but are ether linked, they are not significantly ...
... phospholipid methylene fatty acid Thus, the two substrates of this enzyme are S-adenosyl methionine and phospholipid olefinic ... In enzymology, a methylene-fatty-acyl-phospholipid synthase (EC 2.1.1.16) is an enzyme that catalyzes the chemical reaction S- ... Akamatsu Y, Law JH (1970). "Enzymatic alkylenation of phospholipid fatty acid chains by extracts of Mycobacterium phlei". J. ... The systematic name of this enzyme class is S-adenosyl-L-methionine:unsaturated-phospholipid methyltransferase (methenylating ...
... phospholipid cyclopropane fatty acid Thus, the two substrates of this enzyme are S-adenosyl methionine and phospholipid ... In enzymology, a cyclopropane-fatty-acyl-phospholipid synthase (EC 2.1.1.79) is an enzyme that catalyzes the chemical reaction ... The systematic name of this enzyme class is S-adenosyl-L-methionine:unsaturated-phospholipid methyltransferase (cyclizing). ... Other names in common use include cyclopropane synthetase, unsaturated-phospholipid methyltransferase, cyclopropane synthase, ...
Taylor SS, Heath EC (1969). "The incorporation of beta-hydroxy fatty acids into a phospholipid of Escherichia coli B". J. Biol ... In enzymology, an acyl-[acyl-carrier-protein]-phospholipid O-acyltransferase (EC 2.3.1.40) is an enzyme that catalyzes the ...
Jan 1962). "Phospholipids and coronary mortality. Use of ratio between phospholipid and cholesterol levels to determine ... In the human body, lysoPC (1-lysoPC and 2-lysoPC together) represent 5-20% of all phospholipids in the blood plasma. Taking ... 2-acyl-sn-glycero-3-phosphocholines are a class of phospholipids that are intermediates in the metabolism of lipids. Because ... These differences have been attributed to the remodeling of membrane phospholipids in order to regulate membrane fluidity and ...
McNeil HP, Simpson RJ, Chesterman CN, Krilis SA (1990). "Anti-phospholipid antibodies are directed against a complex antigen ... Since cardiolipin is an important phospholipid found almost exclusively in the inner mitochondrial membrane and very essential ... Gregor Cevc (1993-08-02). Phospholipids handbook. CRC Press. p. 783. ISBN 978-0-8247-9050-9. Antonio Ortiz; J. Antoinette ... Phosphatidylglycerol Pangborn M. (1942). "Isolation and purification of a serologically active phospholipid from beef heart". J ...
LBPA makes up 15-20% of all LE/LY phospholipids and is not found in other subcellular membranes. LBPA is primarily found within ... Lysobisphosphatidic acid (LBPA) (also known as bis(monoacylglycero)phosphate (BMP)) is a phospholipid that is found in the ...
Augmentation by membrane phospholipids". The Journal of Biological Chemistry. 266 (2): 1101-1108. doi:10.1016/S0021-9258(17) ... Annexin A1 belongs to the annexin family of Ca2+-dependent phospholipid-binding proteins that have a molecular weight of ... a Ca2+ and phospholipid binding protein". The Journal of Biological Chemistry. 263 (17): 8037-8043. doi:10.1016/S0021-9258(18) ...
... is a surface-active complex of phospholipids and proteins formed by type II alveolar cells. The proteins ... It also has a higher compaction capacity than the other phospholipids, because the apolar tail is less bent. Nevertheless, ... 40% dipalmitoylphosphatidylcholine (DPPC); ~40% other phospholipids (PC); ~10% surfactant proteins (SP-A, SP-B, SP-C and SP-D ... Dipalmitoylphosphatidylcholine (DPPC) is a phospholipid with two 16-carbon saturated chains and a phosphate group with ...
However, fatty acids are also important components of the phospholipids that form the phospholipid bilayers out of which all ... The effect of this is that, in restricted environments, such as when fatty acids are part of a phospholipid in a lipid bilayer ... phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important dietary sources of fuel for ... phospholipids etc.) and converts them to methyl esters, which are then separated by gas chromatography or analyzed by gas ...
"Fluorescence SpectraViewer - Nile Red phospholipids". Thermo Fisher Scientific. 17 May 2017. Retrieved 6 March 2020. Shafiee, ... in phospholipids (polar lipids), Nile red has an excitation maximum of about 554 nm (green), and an emission maximum of about ...
Some phospholipids, such as phosphatidylcholine, have good solubility in ethanol, whereas most other phospholipids do not ... In hydrolysed lecithins, a portion of the phospholipids have one fatty acid removed by phospholipase. Such phospholipids are ... Purified phospholipids are produced by companies commercially. To modify the performance of lecithin to make it suitable for ... It is a mixture of various phospholipids, and the composition depends on the origin of the lecithin. A major source of lecithin ...
Apart from the setae, phospholipids; fatty substances produced naturally in their bodies, also come into play. These lipids ... "Direct evidence of phospholipids in gecko footprints and spatula-substrate contact interface detected using surface-sensitive ...
ISBN 1-893997-42-1. Liu JJ, Nilsson A, Duan RD (April 2000). "Effects of phospholipids on sphingomyelin hydrolysis induced by ... Some have activity against nucleotides, some have activity against phospholipid and lysophospholipids. ENPP7 is the only enzyme ... phospholipids, and bile salt have been absorbed or up taken. It is also understandable that considerable amount of dietary ... phospholipids, fat and high concentrations of bile salts. It is thus understandable why SM digestion occurs most effectively in ...
It is found in phospholipids. For example, phosphatidylcholines, a major component of biological membranes, are a member of the ...
Of the phospholipids, the most common headgroup is phosphatidylcholine (PC), accounting for about half the phospholipids in ... Phospholipids with certain head groups can alter the surface chemistry of a bilayer and can, for example, serve as signals as ... When phospholipids are exposed to water, they self-assemble into a two-layered sheet with the hydrophobic tails pointing toward ... In phospholipid bilayers the phosphate group is located within this hydrated region, approximately 0.5 nm outside the ...
... (PE) is a class of phospholipids found in biological membranes. They are synthesized by the addition ... Phosphatidylethanolamines are found in all living cells, composing 25% of all phospholipids. In human physiology, they are ... Kelly, Karen (July 28, 2011). "Phospholipid Biosynthesis". The AOCS Lipid Library. Retrieved September 3, 2012. Kuge, Osamu; ... of all phospholipids. Phosphatidylethanolamines play a role in membrane fusion and in disassembly of the contractile ring ...
PEG phospholipid (mPEG-phospholipid, polyglycerin-phospholipid, functionalized-phospholipid, terminal activated-phospholipid) ... The result is often a phospholipid bilayer: a membrane that consists of two layers of oppositely oriented phospholipid ... Liposomes are often composed of phosphatidylcholine-enriched phospholipids and may also contain mixed phospholipid chains with ... Phospholipids can act as emulsifiers, enabling oils to form a colloid with water. Phospholipids are one of the components of ...
The phospholipids stack side-to-side with their oil-loving tails facing inward toward each other and their water-loving heads ... First, the phospholipid heads crowd in at specific places, causing the salt bridge to break. But it doesnt just open up. ... This "dry" slot prevents the phospholipid heads from sliding through.. "When we did the Anton 2 simulations, we found that yes ... This is important because the "wrong" phospholipids showing up on the outside leaflet of the membrane serve as a red flag that ...
Find the Biophysical Society in the News. Press releases, features and headlines.
We reviewed a few plausibly organic syntheses of phospholipids under prebiotic conditions with special attention paid to the ... The synthesis of enantiopure phospholipids from DHAP appeared probably firstly in the presence of chemical catalysts, before ... which are the key molecules to break symmetry in phospholipids. The advantages of homochiral membranes compared to those of ... The asterisk (*) indicates the stereogenic carbon C2 of any phospholipid and phospholipid precursors; Pi stands for any ...
Benefits of Phospholipids on Skin after Topical Application. They provide a barrier for the skin. They hydrate & assist skin ... Phospholipids are extremely useful formulators. They are hygroscopic as they attract water from the air. ...
Exhaled phospholipid transfer protein and hepatocyte growth factor receptor in lung adenocarcinoma. Title: Exhaled phospholipid ... PLTP phospholipid transfer protein [Homo sapiens] PLTP phospholipid transfer protein [Homo sapiens]. Gene ID:5360 ... phospholipid transfer proteinprovided by HGNC. Primary source. HGNC:HGNC:9093 See related. Ensembl:ENSG00000100979 MIM:172425; ... Plasma Phospholipid Transfer Protein Promotes Platelet Aggregation. Zhao XM, et al. Thromb Haemost, 2018 Dec. PMID 30419596, ...
Metabolism, bioaccumulation, and incorporation of diethanolamine into phospholipids. Mathews, J., Garner, C., & Matthews, H. ( ... DEA-derived phosphoglycerides constituted the majority of aberrant phospholipid following acute administration. On repeat ... 1995). Metabolism, bioaccumulation, and incorporation of diethanolamine into phospholipids. Chemical Research in Toxicology, 8( ... toxicity observed on repeat administration of DEA to rats is caused in part by increasing levels of aberrant phospholipids ...
CCT is a key enzyme that maintains a balanced composition of cell membrane phospholipids. This image highlights the dynamics of ...
Structure of the chemokine receptor CXCR1 in phospholipid bilayers.. Park, S.H., Das, B.B., Casagrande, F., Tian, Y., Nothnagel ... The receptor is in liquid crystalline phospholipid bilayers, without modification of its amino acid sequence and under ... underscoring the importance of the phospholipid bilayer for physiological activity. Here we report the three-dimensional ... Structure of human CXCR1 in phospholipid bilayers. *PDB DOI: https://doi.org/10.2210/pdb2LNL/pdb ...
... is preparing to unveil ground breaking discoveries regarding the impact of Nutiani Phospholipids [sourced from milk fat globule ... Unlike single phospholipid sources, Nutiani Phospholipids are broad-spectrum phospholipids, containing a range of major ... Fuad ran a 12-week clinical trial aimed at investigating the effects of phospholipid supplementation via MFGM source on mental ... Fuads presentation at the ISSFAL Congress will provide further insights into the potential of broad-spectrum phospholipids ...
Triglycerides and most phospholipids consist of glycerol and fatty acid chains.. Fatty acids have methyl groups at one end of ... A phospholipid is another common type of lipid. It is an amphipathic molecule, meaning it has a hydrophobic and a hydrophilic ... Glycerophospholipids are a common type of phospholipid that consists of two fatty acids and a highly polar group attached to ... The hydrophilic head groups of the phospholipids face the aqueous solution. The hydrophobic tails are sequestered in the middle ...
View mouse Plpp1 Chr13:112937326-113004428 with: phenotypes, sequences, polymorphisms, proteins, references, function, expression
Phospholipid biosynthesis is crucial for the successful intracellular survival and replication of the parasites, as the ... Die Phospholipid-Biosynthese ist entscheidend für das erfolgreiche intrazelluläre Überleben und die Replikation des ... which suggested a tight inter-regulation and homeostasis of anionic phospholipids to maintain the membrane integrity. In ... phospholipids have important roles in the biogenesis of membrane organelles, signal transduction and other cellular processes. ...
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Phospholipids (PLs) are widely used in the pharma industry and a better understanding of their behavior under different ... Phospholipids (PLs) are widely used in the pharma industry and a better understanding of their behavior under different ... Monolayer/Bilayer Equilibrium of Phospholipids in Gel or Liquid States: Interfacial Adsorption via Monomer or Liposome ...
Low-Phospholipid Associated Cholelithiasis (LPAC) is a genetic disease responsible for the development of intrahepatic ... Low-Phospholipid Associated Cholelithiasis (LPAC) syndrome: A synthetic review J Visc Surg. 2019 Sep;156(4):319-328. doi: ... Low-Phospholipid Associated Cholelithiasis (LPAC) is a genetic disease responsible for the development of intrahepatic ...
Molecular interactions of phospholipid monolayers with a model phospholipase P. Zhang, V. Villanueva, J. Kalkowski, C. Liu, A. ...
Now Sunflower Liquid Lecithin Natural Phospholipids 16oz quantity. Add to cart. SKU: 0733739023728 Categories: Cardiovascular ... NOW® Sunflower Liquid Lecithin has phosphatidyl choline, the most abundant phospholipid in the cell membrane. It also naturally ... Home / Fridge & Pantry / Oils, Vinegars & Sauces / Now Sunflower Liquid Lecithin Natural Phospholipids 16oz. ...
3H]Cho incorporates into the head group of PtdCho, [3H]glycerol incorporates into the phospholipid backbone of phospholipids, [ ... These results show that membrane damage by NMDA is preceded by inhibition of phospholipid synthesis and not by phospholipid ... It is generally assumed that enzymatic hydrolysis of phospholipids leads to phospholipid degradation and membrane damage. ... altered brain membrane phospholipid levels, activation or phospholipases, and/or increased phospholipid degradation have been ...
Glycerol containing phospholipids have been put to extremely wide range of applications. Their applications in medical devices ... Phospholipids And Their Applications In Medicine And Diagnosis. Author(s): A. A Joshi, M. S Nagarsenkar. Glycerol containing ... phospholipids have been put to extremely wide range of applications. Their applications in medical devices, liposomal drug ...
Tags: Alzheimers disease, APOE4, dementia, DHA, nutrition, omega-3, phospholipids, podcast, Rhonda Patrick, Science, ...
A Sustainable Choice for Small Spaces. The leaves of a related species, E. texana (Texas kidneywood) are macerated (soaked) in water and the cold tea is drunk to relieve kidney problems (Quattrocchi, 2012). E. texana can be kept pruned into a small, rugged tree... very attractive. Eysenhardtia texana, commonly known as Texas kidneywood, bee-brush, or vara dulce, is a species of small flowering tree in the legume family, Fabaceae.It is found from south-central Texas south to northern San Luis Potosí in the Rio Grande Valley region of south Texas-Northeastern Mexico, and the species ranges into the eastern Chihuahuan Desert areas of Coahuila. Texas Kidneywood. Kidneywood - A Native Tree. About Civano; Team; Blog; Press & Awards; Contact Us; House Plants; Texas Kidneywood - Eysenhardtia texana. Mine has been vigorous & indestructible. Many pollinators flock to them, & theyre reportedly good honey plants. Tree & Shrubs; Plant catalog; Gardening; Catalog; About. Photo by Don Glentzer. A study ...
Phospholipid Complex May Significantly Improve Cognitive Function: Review. In a review of 1,380 cognition studies, a team of ... Phostphatidylserine is a phospholipid found within the brain, which is implicated in memory and proper nerve cell function. ...
Oxidized phospholipids (OxPL) are ubiquitous, are formed in many inflammatory tissues, including atherosclerotic lesions, and ...
The global Phospholipids Market size was valued at USD 2800 million in 2021 and is expected to expand at a CAGR of 5.22% during ... 1 Phospholipids Market Overview. 1.1 Product Overview and Scope of Phospholipids Market. 1.2 Phospholipids Market Segment by ... Phospholipids Market report analyses the impact of Coronavirus (COVID-19) on the Phospholipids industry. Phospholipids Market ... 3.5 Phospholipids Market Competitive Situation and Trends. 3.5.1 Phospholipids Market Concentration Rate. 3.5.2 Phospholipids ...
This page is Related Information of Improved Analytical Workflow for Phospholipids by Nexera-e and Co-Sense for Impurities. ... title:Downloads,subTitle:Download documents related to the Improved Analytical Workflow for Phospholipids by Nexera-e and ... Improved Analytical Workflow for Phospholipids by Nexera-e and Co-Sense for Impurities - Related Information. ...
Rodriguez, W., Duque, C., Zea, S., Castellanos, L., Ramos, F., Forero, A. M., & Osorno, O. (2022). Phospholipid fatty acids ... Dark CO2 fixation into phospholipid-derived fatty acids by the cold-water coral associated sponge Hymedesmia (Stylopus) ... Novel cyclopropane fatty acids from the phospholipids of the Caribbean sponge Pseudospongosorites suberitoides Lipids , 42(6), ... Scopalina ruetzleri were analyzed to assess their fatty acid composition in the phospholipid fraction. Additionally, the ...
... and Phospholipid (PL) between the Micellar and Vesicular Phases of Human Bile in Vitro: Pilot Studies JPM Ellul; JPM Ellul ... and Phospholipid (PL) between the Micellar and Vesicular Phases of Human Bile in Vitro: Pilot Studies. Clin Sci (Lond) 1 March ...
Fluorescence Recovery after Merging a Droplet to Measure the Two-dimensional Diffusion of a Phospholipid Monolayer. ... Fluorescence Recovery after Merging a Droplet to Measure the Two-dimensional Diffusion of a Phospholipid Monolayer ... Fluorescence Recovery after Merging a Droplet to Measure the Two-dimensional Diffusion of a Phospholipid Monolayer… ...
Phospholipid enrichment in sweet and whey cream buttermilk powders using supercritical fluid extraction.. Title. Phospholipid ... In the dairy industry there are several by-products that are rich in phospholipids (PL) such as buttermilk, whey, and whey ... The total fat, namely nonpolar lipids, in the powders was reduced by 38 to 55%, and phospholipids were concentrated by a factor ... Phospholipid enrichment in sweet and whey cream buttermilk powders using supercritical fluid extraction. ...
  • Phospholipids are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). (wikipedia.org)
  • Lipids are a group of hydrophobic molecules that include triglycerides, which are used to store energy, and phospholipids, which are the major structural components of cell membranes. (jove.com)
  • Novel cyclopropane fatty acids from the phospholipids of the Caribbean sponge Pseudospongosorites suberitoides Lipids , 42(6), 519-524. (usp.br)
  • The total fat, namely nonpolar lipids, in the powders was reduced by 38 to 55%, and phospholipids were concentrated by a factor of 5-fold. (oregonstate.edu)
  • LRH-1 is thought to sense metabolic state by binding a still-undetermined group of greasy molecules: lipids or phospholipids. (emoryhealthsciblog.com)
  • Phospholipids consist of a group of complex lipids with a phosphate group. (kingnature.de)
  • Cell membranes consist to a large extent of phospholipids, therefore phospholipids belong to the membrane lipids. (kingnature.de)
  • Read more about our special lipids in this article from Phospholipid Research Center Heidelberg. (novoarc.at)
  • LNP include lipids, phospholipids, cholesterol and polyethylene glycol (PEG), which increases LNP stability. (cdc.gov)
  • The result is often a phospholipid bilayer: a membrane that consists of two layers of oppositely oriented phospholipid molecules, with their heads exposed to the liquid on both sides, and with the tails directed into the membrane. (wikipedia.org)
  • citation needed] In biological membranes, the phospholipids often occur with other molecules (e.g., proteins, glycolipids, sterols) in a bilayer such as a cell membrane. (wikipedia.org)
  • citation needed] These specific properties allow phospholipids to play an important role in the cell membrane. (wikipedia.org)
  • Sterols contribute to membrane fluidity by hindering the packing together of phospholipids. (wikipedia.org)
  • The cell membrane holds together because its components-called phospholipids-are dual-personality molecules that have an oil-loving tail and a water-loving head. (psc.edu)
  • To escape the water that both fills and surrounds living cells, the membrane forms as two sheets-leaflets-of phospholipids. (psc.edu)
  • So the cell membrane has different types of phospholipids in its inner and outer leaflets. (psc.edu)
  • This is important because the "wrong" phospholipids showing up on the outside leaflet of the membrane serve as a red flag that a cell has developed a serious problem. (psc.edu)
  • Understanding how the cell creates and maintains the mix of phospholipids in their inner and outer membrane leaflets is an important question for a number of human diseases. (psc.edu)
  • These membrane-embedded proteins scramble the proper mix of phospholipids by flipping them in and out. (psc.edu)
  • Cell membrane, showing the two leaflets, each made up of phospholipids with water-loving heads (yellow circles) facing out and fat-loving tails (gray zigzags) facing in. (psc.edu)
  • Khelashvili and Weinstein turned Anton 2 to try to simulate how a family of scramblases called TMEM16 help phospholipids flip to the opposite side of the cell membrane. (psc.edu)
  • Previous laboratory work by other scientists had given rise to the idea that two slots at either end of the TMEM16 scramblase helped the phospholipids flip through from one side to the other by hiding their water-loving heads from the oil-loving interior of the membrane. (psc.edu)
  • CCT is a key enzyme that maintains a balanced composition of cell membrane phospholipids. (asbmb.org)
  • Our previous nuclear magnetic resonance studies indicate that IL-8 binding to the N-terminal residues is mediated by the membrane, underscoring the importance of the phospholipid bilayer for physiological activity. (rcsb.org)
  • Dr. Maher Fuad, a well-respected research clinician at the Fonterra Research and Development Centre (FRDC), is preparing to unveil ground breaking discoveries regarding the impact of Nutiani Phospholipids [sourced from milk fat globule membrane (MFGM)] supplementation on psychological well-being. (fonterra.com)
  • Phospholipid biosynthesis is crucial for the successful intracellular survival and replication of the parasites, as the phospholipids have important roles in the biogenesis of membrane organelles, signal transduction and other cellular processes. (hu-berlin.de)
  • Lipidomic profiling of the PIS mutant demonstrated selective reduction of certain PtdIns and PtdThr species, whereas selected PtdGro, PtdSer and BMP species were increased, which suggested a tight inter-regulation and homeostasis of anionic phospholipids to maintain the membrane integrity. (hu-berlin.de)
  • NOW ® Sunflower Liquid Lecithin has phosphatidyl choline, the most abundant phospholipid in the cell membrane. (highvibe.com)
  • We now investigated the effect of NMDA receptor overactivation on synthesis and degradation of major membrane phospholipids in the early stages of the excitotoxic process. (jneurosci.org)
  • These results show that membrane damage by NMDA is preceded by inhibition of phospholipid synthesis and not by phospholipid degradation in the early stages of the excitotoxic process, and that NMDA receptor overactivation decreases phosphatidylcholine and phosphatidylethanolamine synthesis by inhibiting choline-ethanolaminophosphotransferase activity. (jneurosci.org)
  • Enzymatic hydrolysis of membrane phospholipids by phospholipases produces these lipid second messengers, as well as soluble second messengers such as inositol 1,4,5-trisphosphate, and also other molecules such as choline (Cho) that are released to the extracellular medium. (jneurosci.org)
  • It is generally assumed that enzymatic hydrolysis of phospholipids leads to phospholipid degradation and membrane damage. (jneurosci.org)
  • Phospholipid fatty acids are a main component of the cell membrane ("the skin") of all microbes. (microbe.com)
  • PLAs may generate phospholipid and fatty acid products that recruit effectors of Golgi function and trafficking to the membrane or that affect downstream signaling pathways. (reactome.org)
  • In addition, the non-polar parts of the phospholipids help to promote the fluidity, the flow property, of the membrane. (kingnature.de)
  • Marine phospholipids typically have omega-3 fatty acids EPA and DHA integrated as part of the phospholipid molecule. (wikipedia.org)
  • In aqueous solutions, phospholipids are driven by hydrophobic interactions, which result in the fatty acid tails aggregating to minimize interactions with the water molecules. (wikipedia.org)
  • Oil chemists often use spectroscopy to determine total phosphorus abundance and then calculate approximate mass of phospholipids based on molecular weight of expected fatty acid species. (wikipedia.org)
  • Triglycerides and most phospholipids consist of glycerol and fatty acid chains. (jove.com)
  • Axinella corrugata, Dragmacidon alvarezae, Dragmacidon reticulatum, Ptilocaulis walpersi, Myrmekioderma rea and one sponge belonging to the order Scopalinida: Scopalina ruetzleri were analyzed to assess their fatty acid composition in the phospholipid fraction. (usp.br)
  • 2S*,5S*,6Z)-2,5-epoxydocosan-6-en-21-ynoic acid, new fatty acid from the marine sponge Haliclona fascigera Natural Products Chemistry & Research, 6(5), 19-22. (usp.br)
  • Pioneered by Microbial Insights founder Dr. D.C. White, phospholipid fatty acid analysis (PLFA) is used to quantify total viable biomass and provide a general profile of the microbial community. (microbe.com)
  • As part of a stable isotope probing (SIP) study, phospholipid fatty acid analysis helps answer the question "Is biodegradation is occurring? (microbe.com)
  • Basically, it can be said that a higher proportion of polyunsaturated fatty acids make the phospholipid more valuable. (kingnature.de)
  • The first phospholipid identified in 1847 as such in biological tissues was lecithin, or phosphatidylcholine, in the egg yolk of chickens by the French chemist and pharmacist Theodore Nicolas Gobley. (wikipedia.org)
  • Liposomes are often composed of phosphatidylcholine-enriched phospholipids and may also contain mixed phospholipid chains with surfactant properties. (wikipedia.org)
  • METHODS: The amount and composition of phospholipid classes and phosphatidylcholine molecular species were determined in bronchoalveolar lavage (BAL) fluid and lavaged lungs by high performance liquid chromatography (HPLC). (bmj.com)
  • The amount of SP-A in BAL fluid and the composition of phospholipid as well as phosphatidylcholine molecular species in BAL fluid and lung tissue was unchanged in cftrm1HGU/m1HGU mice compared with controls. (bmj.com)
  • In all cases we observe alterations in the pattern of phospholipids , the more affected ones being phosphatidylcholine , phosphatidylethanolamine and sphingomyelin . (bvsalud.org)
  • We performed molecular dynamics computer simulations to study the orientational dynamics of water next to bilayers containing dilauroyl phosphatidylcholine (DLPC) phospholipids with different hydration levels from 2 to 32 water molecules per lipid . (bvsalud.org)
  • Plasma Phospholipid Transfer Protein Promotes Platelet Aggregation. (nih.gov)
  • Adjusted Prentice-weighted Cox regression estimated HRs and 95% CIs of diabetes in relation to 1 SD lower plasma phospholipid 15:0 and/or 17:0 concentrations or their main contributor, dairy intake, among GAD65Ab-negative and -positive individuals. (lu.se)
  • Conclusions/interpretation: Low plasma phospholipid 17:0 concentrations may promote the progression from GAD65Ab positivity to adult-onset diabetes. (lu.se)
  • Background: Plasma phospholipid pentadecanoic acid (C15:0), heptadecanoic acid (C17:0), and trans-palmitoleic acid (trans-C16:1n-7) are correlates of dairy fat intake. (northwestern.edu)
  • Conclusions: The potential for liver fat to affect relative plasma phospholipid concentrations of C15:0 and C17:0 raises questions about their validity as biomarkers of dairy fat intake. (northwestern.edu)
  • More recently, various betaine-type derivatives having, in general, quaternized alkyl amine groups and at least one phosphorous-containing anion in the molecule referred to hereinafter as "synthetic phospholipids", have been disclosed and suggested as, for example, in U.S. Pat. (justia.com)
  • These synthetic phospholipids are suggested as exhibiting an outstanding combination of surfactant characteristics as well as being well tolerated by human tissue, i.e., they exhibit exceptionally low ocular irritation and oral toxicity. (justia.com)
  • We investigated a phospholipid-protein complex (PPC) from krill that is hypothesized to influence lipid metabolism, inflammation, and redox status. (uib.no)
  • Nutritional deficiencies and phospholipid metabolism. (bvsalud.org)
  • In this review , the effects of macro and micronutrients deficiency on the quality, quantity and metabolism of different phospholipids and their distribution in cells of different organs is presented. (bvsalud.org)
  • Glycerol containing phospholipids have been put to extremely wide range of applications. (ijpsonline.com)
  • In eukaryotes, cell membranes also contain another class of lipid, sterol, interspersed among the phospholipids. (wikipedia.org)
  • PhosphoLipid transfer protein (PLTP) exerts a direct pro-inflammatory effect on rheumatoid arthritis (RA) fibroblasts-like-synoviocytes (FLS) independently of its lipid transfer activity. (nih.gov)
  • Another type of lipid, phospholipids, is an important structural feature of biological membranes. (jove.com)
  • Picture (front): Formation of giant vesicles composed of phospholipid and a flourescent lipid analogue. (lu.se)
  • We reviewed a few plausibly organic syntheses of phospholipids under prebiotic conditions with special attention paid to the starting materials as pro-chiral dihydroxyacetone and dihydroxyacetone phosphate (DHAP), which are the key molecules to break symmetry in phospholipids. (mdpi.com)
  • Phospholipids are typically big, greasy molecules that are hard to deliver as drugs, since they are quickly taken apart by the digestive system," says Eric Ortlund, PhD, associate professor of biochemistry at Emory University School of Medicine. (emoryhealthsciblog.com)
  • Phosphatidyl choline lecithin, phosphatidyl serine, phosphatidylethanolamine and sphingomyelins are among the most common phospholipids in cell membranes. (kingnature.de)
  • The receptor is in liquid crystalline phospholipid bilayers, without modification of its amino acid sequence and under physiological conditions. (rcsb.org)
  • However, the mechanisms by which phospholipases switch from physiological second-messenger production to phospholipid degradation remain unclear. (jneurosci.org)
  • Lung surfactant in a cystic fibrosis animal model: increased alveolar phospholipid pool size without altered composition and surface tension function in cftrm1HGU/m1HGU mice. (bmj.com)
  • BACKGROUND: Progressive pulmonary dysfunction is a characteristic symptom of cystic fibrosis (CF) and is associated with functional impairment and biochemical alterations of surfactant phospholipids in the airways. (bmj.com)
  • CONCLUSION: In cftrm1HGU/m1HGU mice surfactant homeostasis is perturbed by an increased phospholipid pool in the alveolar compartment. (bmj.com)
  • Monolayer/Bilayer Equilibrium of Phospholipids in Gel or Liquid States: Interfacial Adsorption via Monomer or Liposome Diffusion? (nih.gov)
  • and releases arachidonic acid from tissue phospholipids which mediate or modulate one or more cardiovascular effects of angiotensin Bay 65-1942 HCl II and has been implicated in hypertension. (immune-source.com)
  • citation needed] Computational simulations of phospholipids are often performed using molecular dynamics with force fields such as GROMOS, CHARMM, or AMBER. (wikipedia.org)
  • Interaction of phospholipid vesicles with cultured mammalian cells. (rupress.org)
  • Overactivation of NMDA receptors is believed to induce neuronal death by increasing phospholipid hydrolysis and subsequent degradation. (jneurosci.org)
  • On the basis of these results, we hypothesized that excitotoxicity results from inhibition of synthesis rather than from increased degradation of phospholipids. (jneurosci.org)
  • Interestingly, phospholipid degradation was much more pronounced in osmotically challenged radicles that remain sensitive to drying. (inrae.fr)
  • This gene provides instructions for making a protein that releases cholesterol and phospholipids from cells. (medlineplus.gov)
  • Variants in the ABCA1 gene prevent the release of cholesterol and phospholipids from cells. (medlineplus.gov)
  • In addition, the inability to transport cholesterol and phospholipids out of cells results in very low HDL levels, which increases a person's risk of cardiovascular disease. (medlineplus.gov)
  • The leaflets are different from one another in terms of composition … There's a compositional asymmetry, with different phospholipids in the outer leaflet versus the inner leaflet. (psc.edu)
  • Regulation of cardiolipin synthesis and the role of this phospholipid in adriamycin-i . . ." by Diego. (wayne.edu)
  • The phospholipids are amphiphilic. (wikipedia.org)
  • Phospholipids consist of water-loving (hydrophilic) and water-repellent (hydrophobic) components and are highly soluble (amphiphilic) in both polar and non-polar solvents. (kingnature.de)
  • In contrast, NMDA strongly reduced the incorporation of [ 3 H]choline and [ 3 H]ethanolamine into their respective phospholipids. (jneurosci.org)
  • and certain fats called phospholipids from the body's tissues to the liver, where they are removed from the blood. (medlineplus.gov)
  • Phospholipid transfer protein: its impact on lipoprotein homeostasis and atherosclerosis. (nih.gov)
  • The encoded protein transfers phospholipids from triglyceride-rich lipoproteins to high density lipoprotein (HDL). (nih.gov)
  • Bile is isosmotic with plasma and consists primarily of water and electrolytes but also organic compounds: bile salts, phospholipids. (msdmanuals.com)
  • DEA-derived phosphoglycerides constituted the majority of aberrant phospholipid following acute administration. (rti.org)
  • A new study aims to elucidate the relationship of plasma Lp(a) and oxidized phospholipids to acute coronary events. (medscape.com)
  • Lipoprotein(a) and Oxidized Phospholipids: Partners in Crime? (medscape.com)
  • Derived from non-GMO sunflower instead of soy, Empirical Labs Phospholipid Complex provides 5,200 mg of phosphatidycholine (PC) per serving. (drvitaminsolutions.com)
  • Empirical Labs Phospholipid Complex provides 5,200 mg of phosphatidycholine per serving. (drvitaminsolutions.com)
  • Hi I was wondering if I could use a phospholipid complex to create phytosomes by manual addition of embilica officinalis extract? (acs.org)
  • Could I reproduce the same result using an OC phospholipid complex? (acs.org)
  • Phospholipids are very complex. (kingnature.de)
  • Additionally, they underscore the importance of phospholipids in promoting mental well-being. (fonterra.com)
  • Phospholipids (PLs) are widely used in the pharma industry and a better understanding of their behavior under different conditions is helpful for applications such as their use as medical transporters. (nih.gov)
  • HA inhibited by choline-containing phospholipids. (cdc.gov)
  • While these known phospholipids have been found useful as surfactants in a variety of personal care, household cleaning and the like products, such products also require the incorporation of antimicrobial preservatives to inhibit microbial spoilage and increase the shelf life. (justia.com)
  • citation needed] Phospholipids are a key component of all cell membranes. (wikipedia.org)
  • One of the first lines of defense against cancer, for example, is when cells are damaged and start to destroy themselves in a process known as "programmed cell death," specialized neighboring cells recognize the "wrong" phospholipids and eliminate the damaged cell. (psc.edu)
  • Phostphatidylserine is a phospholipid found within the brain, which is implicated in memory and proper nerve cell function. (nutraceuticalsworld.com)
  • Phospholipids are important components of the cell membranes of all living species. (bvsalud.org)
  • In addition, three derivatives arising early during phospholipid catabolism (glycerylphosphorylcholine, glycerylphosphorylethanolamine and glycerylphosphorylinositol) appeared in the PEG-treated radicles. (inrae.fr)
  • Exclusion criteria were diabetes, phospholipids. (who.int)
  • In collaboration with teams from The University of Auckland and the University of Otago, Dr. Fuad ran a 12-week clinical trial aimed at investigating the effects of phospholipid supplementation via MFGM source on mental well-being in healthy adults facing moderate stress. (fonterra.com)
  • The report combines extensive quantitative analysis and exhaustive qualitative analysis, ranges from a macro overview of the total market size, industry chain, and market dynamics to micro details of segment markets by type, application and region, and, as a result, provides a holistic view of, as well as a deep insight into the Phospholipids market covering all its essential aspects. (digitaljournal.com)
  • RESULTS: BAL fluid of cftrm1HGU/m1HGU mice contained 1.02 (95% confidence interval (CI) 0.89 to 1.16) mumol phospholipid and 259 (239 to 279) ng SP-A. BAL fluid of MF1, BALB/c, C57BL/6, and C3H/He mice contained 0.69 (0.63 to 0.75), 0.50 (0.42 to 0.57), 0.52 (0.40 to 0.64), and 0.45 (0.27 to 0.63) mumol phospholipid, respectively. (bmj.com)
  • The increase in phospholipids in BAL fluid of cftrm1HGU/m1HGU mice resulted from an increased fraction of large aggregates which exhibited normal surface tension function. (bmj.com)
  • Phospholipids are found in all animal and plant cells. (kingnature.de)
  • Purified phospholipids are produced commercially and have found applications in nanotechnology and materials science. (wikipedia.org)
  • Participants who received Nutiani Phospholipids supplementation experienced significant reductions in stress levels compared to those in the placebo group. (fonterra.com)
  • The findings underscore the significant impact of broad-spectrum phospholipid supplementation in reducing stress levels and offer hope for anxiety alleviation. (fonterra.com)
  • Dr. Fuad's presentation at the ISSFAL Congress will provide further insights into the potential of broad-spectrum phospholipids sourced from MFGM to enhance psychological well-being, instilling hope for effective interventions. (fonterra.com)