Membranes. Medical search

Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.

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.

The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.

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.

The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).

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.

The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.

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.

A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.

A darkly stained mat-like EXTRACELLULAR MATRIX (ECM) that separates cell layers, such as EPITHELIUM from ENDOTHELIUM or a layer of CONNECTIVE TISSUE. The ECM layer that supports an overlying EPITHELIUM or ENDOTHELIUM is called basal lamina. Basement membrane (BM) can be formed by the fusion of either two adjacent basal laminae or a basal lamina with an adjacent reticular lamina of connective tissue. BM, composed mainly of TYPE IV COLLAGEN; glycoprotein LAMININ; and PROTEOGLYCAN, provides barriers as well as channels between interacting cell layers.

Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.

Glycoproteins found on the membrane or surface of cells.

Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.

The two lipoprotein layers in the MITOCHONDRION. The outer membrane encloses the entire mitochondrion and contains channels with TRANSPORT PROTEINS to move molecules and ions in and out of the organelle. The inner membrane folds into cristae and contains many ENZYMES important to cell METABOLISM and energy production (MITOCHONDRIAL ATP SYNTHASE).

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.

The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.

Cell membranes associated with synapses. Both presynaptic and postsynaptic membranes are included along with their integral or tightly associated specializations for the release or reception of transmitters.

Established cell cultures that have the potential to propagate indefinitely.

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.

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.

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.

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.

Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.

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.

Transport proteins that carry specific substances in the blood or across cell membranes.

The thin layers of tissue that surround the developing embryo. There are four extra-embryonic membranes commonly found in VERTEBRATES, such as REPTILES; BIRDS; and MAMMALS. They are the YOLK SAC, the ALLANTOIS, the AMNION, and the CHORION. These membranes provide protection and means to transport nutrients and wastes.

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)

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.

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.

Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.

A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)

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.

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.

A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)

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.

Proteins found in any species of bacterium.

Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.

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.

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.

The sum of the weight of all the atoms in a molecule.

Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.

Structures which are part of the CELL MEMBRANE or have cell membrane as a major part of their structure.

An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.

Minute projections of cell membranes which greatly increase the surface area of the cell.

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.

Components of a cell produced by various separation techniques which, though they disrupt the delicate anatomy of a cell, preserve the structure and physiology of its functioning constituents for biochemical and ultrastructural analysis. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p163)

Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)

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.

The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.

Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.

A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.

The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)

Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.

Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.

The parts of a macromolecule that directly participate in its specific combination with another molecule.

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.

The voltage difference, normally maintained at approximately -180mV, across the INNER MITOCHONDRIAL MEMBRANE, by a net movement of positive charge across the membrane. It is a major component of the PROTON MOTIVE FORCE in MITOCHONDRIA used to drive the synthesis of ATP.

Functionally and structurally differentiated, purple-pigmented regions of the cytoplasmic membrane of some strains of Halobacterium halobium. The membrane develops under anaerobic conditions and is made almost entirely of the purple pigment BACTERIORHODOPSINS. (From Singleton & Sainsbury Dictionary of Microbiology and Molecular Biology, 2d ed)

Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.

Elements of limited time intervals, contributing to particular results or situations.

A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.

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).

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)

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 sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.

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 adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.

The ability of a substrate to allow the passage of ELECTRONS.

A fold of the mucous membrane of the CONJUNCTIVA in many animals. At rest, it is hidden in the medial canthus. It can extend to cover part or all of the cornea to help clean the CORNEA.

The inner layer of CHOROID, also called the lamina basalis choroideae, located adjacent to the RETINAL PIGMENT EPITHELIUM; (RPE) of the EYE. It is a membrane composed of the basement membranes of the choriocapillaris ENDOTHELIUM and that of the RPE. The membrane stops at the OPTIC NERVE, as does the RPE.

Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.

The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.

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.

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.

Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays.

Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.

Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.

A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.

The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.

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.

Proteins prepared by recombinant DNA technology.

The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.

The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.

Cytoplasmic vesicles formed when COATED VESICLES shed their CLATHRIN coat. Endosomes internalize macromolecules bound by receptors on the cell surface.

Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.

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.

Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion.

The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.

Proteins obtained from ESCHERICHIA COLI.

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.

The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.

Porins are protein molecules that were originally found in the outer membrane of GRAM-NEGATIVE BACTERIA and that form multi-meric channels for the passive DIFFUSION of WATER; IONS; or other small molecules. Porins are present in bacterial CELL WALLS, as well as in plant, fungal, mammalian and other vertebrate CELL MEMBRANES and MITOCHONDRIAL MEMBRANES.

The rate dynamics in chemical or physical systems.

Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.

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)

Single membrane vesicles, generally made of PHOSPHOLIPIDS.

The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.

Measurement of the intensity and quality of fluorescence.

Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.

Spontaneous tearing of the membranes surrounding the FETUS any time before the onset of OBSTETRIC LABOR. Preterm PROM is membrane rupture before 37 weeks of GESTATION.

Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.

An oval semitransparent membrane separating the external EAR CANAL from the tympanic cavity (EAR, MIDDLE). It contains three layers: the skin of the external ear canal; the core of radially and circularly arranged collagen fibers; and the MUCOSA of the middle ear.

A layer of the cornea. It is the basal lamina of the CORNEAL ENDOTHELIUM (from which it is secreted) separating it from the CORNEAL STROMA. It is a homogeneous structure composed of fine collagenous filaments, and slowly increases in thickness with age.

Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.

CELL LINES derived from the CV-1 cell line by transformation with a replication origin defective mutant of SV40 VIRUS, which codes for wild type large T antigen (ANTIGENS, POLYOMAVIRUS TRANSFORMING). They are used for transfection and cloning. (The CV-1 cell line was derived from the kidney of an adult male African green monkey (CERCOPITHECUS AETHIOPS).)

The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.

The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)

The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.

Application of a life support system that circulates the blood through an oxygenating system, which may consist of a pump, a membrane oxygenator, and a heat exchanger. Examples of its use are to assist victims of smoke inhalation injury, respiratory failure, and cardiac failure.

Vesicles that are involved in shuttling cargo from the interior of the cell to the cell surface, from the cell surface to the interior, across the cell or around the cell to various locations.

A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured. Such rupture is supposed to be under metabolic (hormonal) control. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)

Amino acid sequences found in transported proteins that selectively guide the distribution of the proteins to specific cellular compartments.

The thermodynamic interaction between a substance and WATER.

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)

Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.

A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. It is formed by the sequential assembly of terminal complement components (COMPLEMENT C5B; COMPLEMENT C6; COMPLEMENT C7; COMPLEMENT C8; and COMPLEMENT C9) into the target membrane. The resultant C5b-8-poly-C9 is the "membrane attack complex" or MAC.

Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.

A replica technique in which cells are frozen to a very low temperature and cracked with a knife blade to expose the interior surfaces of the cells or cell membranes. The cracked cell surfaces are then freeze-dried to expose their constituents. The surfaces are now ready for shadowing to be viewed using an electron microscope. This method differs from freeze-fracturing in that no cryoprotectant is used and, thus, allows for the sublimation of water during the freeze-drying process to etch the surfaces.

Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.

CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.

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.

Ubiquitously expressed integral membrane glycoproteins found in the LYSOSOME.

Orientation of intracellular structures especially with respect to the apical and basolateral domains of the plasma membrane. Polarized cells must direct proteins from the Golgi apparatus to the appropriate domain since tight junctions prevent proteins from diffusing between the two domains.

Multisubunit enzymes that reversibly synthesize ADENOSINE TRIPHOSPHATE. They are coupled to the transport of protons across a membrane.

An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.

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.

The plasma membrane of the egg.

Calcium-transporting ATPases found on the PLASMA MEMBRANE that catalyze the active transport of CALCIUM from the CYTOPLASM into the extracellular space. They play a role in maintaining a CALCIUM gradient across plasma membrane.

The innermost membranous sac that surrounds and protects the developing embryo which is bathed in the AMNIOTIC FLUID. Amnion cells are secretory EPITHELIAL CELLS and contribute to the amniotic fluid.

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.

Histochemical localization of immunoreactive substances using labeled antibodies as reagents.

A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.

Proteins involved in the transport of specific substances across the membranes of the MITOCHONDRIA.

Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

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)

Cyclic GLUCANS consisting of seven (7) glucopyranose units linked by 1,4-glycosidic bonds.

Regulatory proteins that act as molecular switches. They control a wide range of biological processes including: receptor signaling, intracellular signal transduction pathways, and protein synthesis. Their activity is regulated by factors that control their ability to bind to and hydrolyze GTP to GDP. EC 3.6.1.-.

An enzyme that catalyzes the active transport system of sodium and potassium ions across the cell wall. Sodium and potassium ions are closely coupled with membrane ATPase which undergoes phosphorylation and dephosphorylation, thereby providing energy for transport of these ions against concentration gradients.

Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.

Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.

The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.

A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.

Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.

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.

Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.

Specific particles of membrane-bound organized living substances present in eukaryotic cells, such as the MITOCHONDRIA; the GOLGI APPARATUS; ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.

The membrane system of the CELL NUCLEUS that surrounds the nucleoplasm. It consists of two concentric membranes separated by the perinuclear space. The structures of the envelope where it opens to the cytoplasm are called the nuclear pores (NUCLEAR PORE).

The relationship between the dose of an administered drug and the response of the organism to the drug.

A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.

A high molecular weight (220-250 kDa) water-soluble protein which can be extracted from erythrocyte ghosts in low ionic strength buffers. The protein contains no lipids or carbohydrates, is the predominant species of peripheral erythrocyte membrane proteins, and exists as a fibrous coating on the inner, cytoplasmic surface of the membrane.

A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.

Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.

A basement membrane in the cochlea that supports the hair cells of the ORGAN OF CORTI, consisting keratin-like fibrils. It stretches from the SPIRAL LAMINA to the basilar crest. The movement of fluid in the cochlea, induced by sound, causes displacement of the basilar membrane and subsequent stimulation of the attached hair cells which transform the mechanical signal into neural activity.

One or more layers of EPITHELIAL CELLS, supported by the basal lamina, which covers the inner or outer surfaces of the body.

A cyclododecadepsipeptide ionophore antibiotic produced by Streptomyces fulvissimus and related to the enniatins. It is composed of 3 moles each of L-valine, D-alpha-hydroxyisovaleric acid, D-valine, and L-lactic acid linked alternately to form a 36-membered ring. (From Merck Index, 11th ed) Valinomycin is a potassium selective ionophore and is commonly used as a tool in biochemical studies.

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.

Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.

Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.

Condensed areas of cellular material that may be bounded by a membrane.

Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.

RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.

Antibodies produced by a single clone of cells.

The characteristic three-dimensional shape of a molecule.

A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.

The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.

Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.

Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.

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.

Surface glycoproteins on platelets which have a key role in hemostasis and thrombosis such as platelet adhesion and aggregation. Many of these are receptors.

The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.

Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.

Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.

Negatively charged atoms, radicals or groups of atoms which travel to the anode or positive pole during electrolysis.

The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

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.

Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.

A major integral transmembrane protein of the ERYTHROCYTE MEMBRANE. It is the anion exchanger responsible for electroneutral transporting in CHLORIDE IONS in exchange of BICARBONATE IONS allowing CO2 uptake and transport from tissues to lungs by the red blood cells. Genetic mutations that result in a loss of the protein function have been associated with type 4 HEREDITARY SPHEROCYTOSIS.

The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.

Compounds containing carbohydrate or glycosyl groups linked to phosphatidylinositols. They anchor GPI-LINKED PROTEINS or polysaccharides to cell membranes.

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.

Membrane-limited structures derived from the plasma membrane or various intracellular membranes which function in storage, transport or metabolism.

Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.

A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.

Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.

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.

A fungal metabolite which is a macrocyclic lactone exhibiting a wide range of antibiotic activity.

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)

The movement of ions across energy-transducing cell membranes. Transport can be active, passive or facilitated. Ions may travel by themselves (uniport), or as a group of two or more ions in the same (symport) or opposite (antiport) directions.

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)

Tendency of fluids (e.g., water) to move from the less concentrated to the more concentrated side of a semipermeable membrane.

Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).

The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.

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.

Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.

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)

The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.

The process of cleaving a chemical compound by the addition of a molecule of water.

A tyrosine phosphoprotein that plays an essential role in CAVEOLAE formation. It binds CHOLESTEROL and is involved in LIPIDS transport, membrane traffic, and SIGNAL TRANSDUCTION.

A class of porins that allow the passage of WATER and other small molecules across CELL MEMBRANES.

Membranous cisternae of the CHLOROPLAST containing photosynthetic pigments, reaction centers, and the electron-transport chain. Each thylakoid consists of a flattened sac of membrane enclosing a narrow intra-thylakoid space (Lackie and Dow, Dictionary of Cell Biology, 2nd ed). Individual thylakoids are interconnected and tend to stack to form aggregates called grana. They are found in cyanobacteria and all plants.

Extra-vesicular binding of noradrenaline and guanethidine in the adrenergic neurones of the rat heart: a proposed site of action of adrenergic neurone blocking agents. (1/2566)

1 The binding and efflux characteristics of [14C]-guanethidine and [3H]-noradrenaline were studied in heart slices from rats which were pretreated with reserpine and nialamide. 2 Binding of both compounds occurred at extra-vesicular sites within the adrenergic neurone. After a brief period of rapid washout, the efflux of [14C]-guanethidine and [3H]-noradrenaline proceeded at a steady rate. The efflux of both compounds appeared to occur from a single intraneuronal compartment. 3 (+)-Amphetamine accelerated the efflux of [14C]-noradrenaline; this effect was inhibited by desipramine. 4 Unlabelled guanethidine and amantadine also increased the efflux of labelled compounds. Cocaine in high concentrations increased slightly the efflux of [14C]-guanethidine but not that of [3H]-noradrenaline. 5 Heart slices labelled with [3H]-noradrenaline became refractory to successive exposures to releasing agents although an appreciable amount of labelled compound was still present in in these slices. 6 It is suggested that [14C]-guanethidine and [3H]-noradrenaline are bound at a common extravesicular site within the adrenergic neurone. Binding of guanethidine to the extra-vesicular site may be relevant to its pharmacological action, i.e., the blockade of adrenergic transmission. (+info)

The Saccharomyces cerevisiae CWH8 gene is required for full levels of dolichol-linked oligosaccharides in the endoplasmic reticulum and for efficient N-glycosylation. (2/2566)

The Saccharomyces cerevisiae mutant cwh8 was previously found to have an anomalous cell wall. Here we show that the cwh8 mutant has an N -glycosylation defect. We found that cwh8 cells were resistant to vanadate and sensitive to hygromycin B, and produced glycoforms of invertase and carboxypeptidase Y with a reduced number of N -chains. We have cloned the CWH8 gene. We found that it was nonessential and encoded a putative transmembrane protein of 239 amino acids. Comparison of the in vitro oligosaccharyl transferase activities of membrane preparations from wild type or cwh8 Delta cells revealed no differences in enzyme kinetic properties indicating that the oligosaccharyl transferase complex of mutant cells was not affected. cwh8 Delta cells also produced normal dolichols and dolichol-linked oligosaccharide intermediates including the full-length form Glc3Man9GlcNAc2. The level of dolichol-linked oligosaccharides in cwh8 Delta cells was, however, reduced to about 20% of the wild type. We propose that inefficient N -glycosylation of secretory proteins in cwh8 Delta cells is caused by an insufficient supply of dolichol-linked oligosaccharide substrate. (+info)

Isolation and characterization of major intrinsic microsomal membrane proteins. (3/2566)

Treatment of the membrane matrix derived from hepatic microsomes with buffered 1 M urea resulted in the selective extraction of a group of proteins together with a portion of the membrane lipid. Thorough chemical characterization of this fraction has been performed, and the proteins have been fractionated by two different procedures. The first of these, preparative polyacrylamide gel electrophoresis, has produced five highly homogeneous membrane proteins which have been characterized with regard to molecular weight, electrophoretic behavior in five different polyacrylamide systems, NH2 terminus, relative carbohydrate content, isoelectric point, and amino acid composition. The five proteins of this group fell in the molecular weight range of 54,000 to 96,000 and had isoelectric points ranging from pH 4.9 to pH 6.7. Further fractionation of the urea-soluble proteins by gel filtration in a sodium dodecyl sulfate-containing medium resulted in the isolation of four homogeneous molecular weight classes of proteins which have been characterized with respect to various physicochemical parameters. The major membrane glycoprotein (apparent molecular weight, 171,000) was isolated by this procedure and found to contain approximately equal amounts of NH2-terminal glycine and serine. suggesting the presence of at least two polypeptide chains in this molecular weight region. From the urea-insoluble fraction of the membrane comprising approximately 80% of the total protein, five intrinsic polypeptides designated S-5 through S-9 were isolated. S-5 (54,000) and S-6 (49,000) represent the most prominent components in the microsomal membrane, accounting for close to 30% of the total protein. Also isolated and characterized is the smallest membrane protein (S-9), a hydrophobic polypeptide of molecular weight 16,000. All of the urea-insoluble proteins are glycoproteins, and S-7 (35,000) gives the second most intense stain for carbohydrate of all proteins in the microsomal membrane. (+info)

Kinetic analysis of drug-receptor interactions of long-acting beta2 sympathomimetics in isolated receptor membranes: evidence against prolonged effects of salmeterol and formoterol on receptor-coupled adenylyl cyclase. (4/2566)

The long-acting beta2 sympathomimetics salmeterol and formoterol have been presumed to exert their prolonged action either by binding to an accessory binding site ("exo-site") near the beta2 adrenoceptor or by their high affinity for beta2 adrenoceptors and correspondingly slow dissociation. Whereas most studies with salmeterol had been done in intact tissues, which have slow diffusion and compartmentation of drugs in lipophilic phases, that restrict drug access to the receptor biophase, we used purified receptor membranes from rat lung and disaggregated calf tracheal myocytes as model systems. Binding experiments were designed to measure the slow dissociation of agonists by means of delayed association of (-)-[125I]iodopindolol. Rat lung membranes were pretreated with high concentrations of agonists (salmeterol, formoterol, isoprenaline) before dissociation was induced by 50-fold dilution. Half-times of association of (-)-[125I]iodopindolol remained unchanged compared with untreated controls, indicating that dissociation of agonists occurred in less than 2 min. Adenylyl cyclase experiments were designed to determine the on and off kinetics of agonists to beta2 adrenoceptors by measuring the rate of receptor-induced cyclic AMP (cAMP) formation. Experiments were performed in tracheal membranes characterized by high Vmax values of cAMP formation. Adenylyl cyclase activation occurred simultaneously with the addition of the agonist, continued linearly with time for 60 min, and ceased immediately after the antagonist was added. Similarly, when receptor membranes were preincubated in a small volume with high salmeterol concentrations, there was a linear increase in cAMP formation, which was immediately interrupted by a 100-fold dilution of the reaction mixture. This militates against the exo-site hypothesis. On the other hand, dissociation by dilution was much less when membranes were preincubated with a large volume of salmeterol at the same concentration, indicating that physicochemical effects, and not exo-site binding, underlie its prolonged mode of action. (+info)

Biochemical and electrophysiological studies on the mechanism of action of PNU-151774E, a novel antiepileptic compound. (5/2566)

PNU-151774E [(S)-(+)-2-(4-(3-fluorobenzyloxy)benzylamino)propanamide methanesulfonate], a new anticonvulsant that displays a wide therapeutic window, has a potency comparable or superior to that of most classic anticonvulsants. PNU-151774E is chemically unrelated to current antiepileptics. In animal seizure models it possesses a broad spectrum of action. In the present study, the action mechanism of PNU-151774E has been investigated using electrophysiological and biochemical assays. Binding studies performed with rat brain membranes show that PNU-151774E has high affinity for binding site 2 of the sodium channel receptor, which is greater than that of phenytoin or lamotrigine (IC50, 8 microM versus 47 and 185 microM, respectively). PNU-151774E reduces sustained repetitive firing in a use-dependent manner without modifying the first action potential in hippocampal cultured neurons. In the same preparation PNU-151774E inhibits tetrodotoxin-sensitive fast sodium currents and high voltage-activated calcium currents under voltage-clamp conditions. These electrophysiological activities of PNU-151774E correlate with its ability to inhibit veratrine and KCl-induced glutamate release in rat hippocampal slices (IC50, 56.4 and 185.5 microM, respectively) and calcium inward currents in mouse cortical neurons. On the other hand, PNU-151774E does not affect whole-cell gamma-aminobutryic acid- and glutamate-induced currents in cultured mouse cortical neurons. These results suggest that PNU-151774E exerts its anticonvulsant activity, at least in part, through inhibition of sodium and calcium channels, stabilizing neuronal membrane excitability and inhibiting transmitter release. The possible relevance of these pharmacological properties to its antiepileptic potential is discussed. (+info)

Localization and environment of tryptophans in soluble and membrane-bound states of a pore-forming toxin from Staphylococcus aureus. (6/2566)

The location and environment of tryptophans in the soluble and membrane-bound forms of Staphylococcus aureus alpha-toxin were monitored using intrinsic tryptophan fluorescence. Fluorescence quenching of the toxin monomer in solution indicated varying degrees of tryptophan burial within the protein interior. N-Bromosuccinimide readily abolished 80% of the fluorescence in solution. The residual fluorescence of the modified toxin showed a blue-shifted emission maximum, a longer fluorescence lifetime as compared to the unmodified and membrane-bound alpha-toxin, and a 5- to 6-nm red edge excitation shift, all indicating a restricted tryptophan environment and deeply buried tryptophans. In the membrane-bound form, the fluorescence of alpha-toxin was quenched by iodide, indicating a conformational change leading to exposure of some tryptophans. A shorter average lifetime of tryptophans in the membrane-bound alpha-toxin as compared to the native toxin supported the conclusions based on iodide quenching of the membrane-bound toxin. Fluorescence quenching of membrane-bound alpha-toxin using brominated and spin-labeled fatty acids showed no quenching of fluorescence using brominated lipids. However, significant quenching was observed using 5- and 12-doxyl stearic acids. An average depth calculation using the parallax method indicated that the doxyl-quenchable tryptophans are located at an average depth of 10 A from the center of the bilayer close to the membrane interface. This was found to be in striking agreement with the recently described structure of the membrane-bound form of alpha-toxin. (+info)

Cellular mechanisms contributing to response variability of cortical neurons in vivo. (7/2566)

Cortical neurons recorded in vivo exhibit highly variable responses to the repeated presentation of the same stimulus. To further understand the cellular mechanisms underlying this phenomenon, we performed intracellular recordings from neurons in cat striate cortex in vivo and examined the relationships between spontaneous activity and visually evoked responses. Activity was assessed on a trial-by-trial basis by measuring the membrane potential (Vm) fluctuations and spike activity during brief epochs immediately before and after the onset of an evoked response. We found that the response magnitude, expressed as a change in Vm relative to baseline, was linearly correlated with the preceding spontaneous Vm. This correlation was enhanced when the cells were hyperpolarized to reduce the activation of voltage-gated conductances. The output of the cells, expressed as spike counts and latencies, was only moderately correlated with fluctuations in the preceding spontaneous Vm. Spike-triggered averaging of Vm revealed that visually evoked action potentials arise from transient depolarizations having a rise time of approximately 10 msec. Consistent with this, evoked spike count was found to be linearly correlated with the magnitude of Vm fluctuations in the gamma (20-70 Hz) frequency band. We also found that the threshold of visually evoked action potentials varied over a range of approximately 10 mV. Examination of simultaneously recorded intracellular and extracellular activity revealed a correlation between Vm depolarization and spike discharges in adjacent cells. Together these results demonstrate that response variability is attributable largely to coherent fluctuations in cortical activity preceding the onset of a stimulus, but also to variations in action potential threshold and the magnitude of high-frequency fluctuations evoked by the stimulus. (+info)

Direct evidence of Na+/Ca2+ exchange in squid rhabdomeric membranes. (8/2566)

Na+/Ca2+ exchange has been investigated in squid (Loligo pealei) rhabdomeric membranes. Ca2+-containing vesicles have been prepared from purified rhabdomeric membranes by extrusion through polycarbonate filters of 1-micrometer pore size. After removal of external Ca2+, up to 90% of the entrapped Ca2+ could be specifically released by the addition of Na+; this finding indicates that most of the vesicles contained Na+/Ca2+ exchanger. The Na+-induced Ca2+ efflux had a half-maximum value (K1/2) of approximately 44 mM and a Hill coefficient of approximately 1.7. The maximal Na+-induced Ca2+ efflux was approximately 0.6 nmol Ca2+. s-1. mg protein-1. Similar Na+-induced Ca2+ effluxes were measured if K+ was replaced with Li+ or Cs+. Vesicles loaded with Ca2+ by Na+/Ca2+ exchange also released this Ca2+ by Na+/Ca2+ exchange, suggesting that Na+/Ca2+ exchange operated in both forward and reverse modes. Limited proteolysis by trypsin resulted in a rate of Ca2+ efflux enhanced by approximately fivefold when efflux was activated with 95 mM NaCl. For vesicles subjected to limited proteolysis by trypsin, Na+/Ca2+ exchange was characterized by a K1/2 of approximately 25 mM and a Hill coefficient of 1.6. For these vesicles, the maximal Na+-induced Ca2+ efflux was about twice as great as in control vesicles. We conclude that Na+/Ca2+ exchange proteins localized in rhabdomeric membranes mediate Ca2+ extrusion in squid photoreceptors. (+info)

The fetal membranes separate maternal tissue from fetal tissue at a basic mechanical level. The fetal membrane is composed of a ... The fetal membranes surround the developing embryo and form the fetal-maternal interface. The fetal membranes are derived from ... The fetal membranes are the four extraembryonic membranes, associated with the developing embryo, and fetus in humans and other ... It has been suggested that the presence of more fetal membrane microfractures may mean the fetal membranes may be predisposed ...

https://en.wikipedia.org/wiki/Fetal_membranes

Membrane systems are suitable to represent the evolution of objects and movement of objects and membranes through membranes. A ... Hence, an additional layer of membrane is created around the eaten membrane: the patch on that membrane is specified by the ... Here we motivate and present the mobile membranes. Mobile membranes represent a variant of membrane systems inspired by the ... namely moving a membrane inside a neighbouring membrane, or outside the membrane where it is placed, respectively. The ...

https://en.wikipedia.org/wiki/Mobile_membranes

... by The Membranes". Membranes.bandcamp.com. Retrieved 14 September 2020. Official website (Articles with short description, ... The Membranes are an English post-punk band formed in Blackpool, Lancashire in 1977, the initial line-up being John Robb (bass ... After The Membranes, Robb went on to form Sensuround and later Goldblade. In 2009, the band reformed after My Bloody Valentine ... Inspired by punk rock and the DIY ethic of punk, they started both a fanzine, Rox, and The Membranes at the same time. Tilton, ...

https://en.wikipedia.org/wiki/The_Membranes

AROM: artificial rupture of membranes. This term describes a rupture of the membranes by a third party, usually a midwife or ... PROM: premature rupture of membranes. This term describes a rupture of the membranes that occurs before the onset of labor. ... SROM: spontaneous rupture of membranes. This term describes the normal, spontaneous rupture of the membranes at full term. The ... PPROM: preterm, premature rupture of membranes. This term describes a rupture of the membranes that occurs before 37 weeks ...

https://en.wikipedia.org/wiki/Rupture_of_membranes

These closed membranes are double membrane-bond, with lysosomes inside it. The main function of these membrane is degradation, ... The mitochondria-associated ER membranes (MAMs), play role in cell death modulation. Mitochondrial outer membrane ... Mitochondrion Neurodegeneration Membrane contact site Alzheimer's disease Parkinson's disease Membrane contact site Vance, Jean ... These membranes are involved in import of certain lipids from the ER to mitochondria and in regulation of calcium homeostasis, ...

https://en.wikipedia.org/wiki/Mitochondria_associated_membranes

The membranes can be ruptured using a specialized tool, such as an amnihook or amnicot, or they may be ruptured by the ... With the membranes punctured, amniotic fluid is able to escape from the uterus and exit the vagina. The absence of a fluid ... Artificial rupture of membranes (AROM), also known as an amniotomy, is performed by a midwife or obstetrician and was once ... With the amnihook method, a sterile plastic hook is inserted into the vagina and used to puncture the membranes containing the ...

https://en.wikipedia.org/wiki/Artificial_rupture_of_membranes

Sealing membranes after rupture: Infection is the major risk associated with PROM and PPROM. By closing the ruptured membranes ... Prelabor rupture of membranes (PROM), previously known as premature rupture of membranes, is breakage of the amniotic sac ... Fibronectin and alpha-fetoprotein blood tests Prelabor rupture of membranes (PROM): when the fetal membranes rupture early, at ... Preterm prelabor rupture of membranes (PPROM): prelabor rupture of membranes that occurs before 37 weeks gestation. ...

https://en.wikipedia.org/wiki/Prelabor_rupture_of_membranes

A cell membrane defines a boundary between a cell and its environment. The primary constituent of a membrane is a phospholipid ... The membrane skeleton is a network of proteins below the bilayer that links with the proteins in the lipid membrane. The ... A cell membrane is simplified as lipid bilayer plus membrane skeleton. The skeleton is a cross-linking protein network and ... The Conformation of Membranes, Nature 349 (1991) 475-481. [2] U. Seifert, Configurations of Fluid Membranes and Vesicles, Adv. ...

https://en.wikipedia.org/wiki/Elasticity_of_cell_membranes

Membranes can be generally classified into synthetic membranes and biological membranes. Biological membranes include cell ... The water to be treated passes between the membranes of two adjacent membrane assemblies. The plate supports the membranes and ... Physical cleaning techniques for membrane include membrane relaxation and membrane backwashing. Back-washing or back-flushing ... "Potential of mechanical cleaning of membranes from a membrane bioreactor". Journal of membrane science. 429, 2013. 259-267. ...

https://en.wikipedia.org/wiki/Membrane

... a triangular membrane occurring in eyes Cell membranes: Plasma membrane, a membrane that separates the interior of all cells ... a smooth membrane consisting of a thin layer of cells, which secrete serous fluid Tunic membrane, protective membrane covering ... like biological membranes. Membrane may also refer to: Look up membrane in Wiktionary, the free dictionary. Biology: Isolating ... flexible surface Membrane structure, a sort of spatial structure made of tensioned membranes Membrane (M-Theory), a spatially ...

https://en.wikipedia.org/wiki/Membrane_(disambiguation)

... s also form a matrix in which membrane proteins reside. Historically lipids were thought to merely serve a ... Cell membranes require high levels of cholesterol - typically an average of 20% cholesterol in the whole membrane, increasing ... Wikimedia Commons has media related to Membrane lipids. Membrane+lipids at the US National Library of Medicine Medical Subject ... Membrane lipids are a group of compounds (structurally similar to fats and oils) which form the double-layered surface of all ...

https://en.wikipedia.org/wiki/Membrane_lipid

... Muscles, nerves and arteries of neck. Deep dissection. Anterior ... The thyrohyoid membrane (or hyothyroid membrane) is a broad, fibro-elastic sheet of the larynx. It connects the upper border of ... The thyrohyoid membrane needs to be manipulated to access the superior thyroid artery. The thyrohyoid membrane refers to the ... The thyrohyoid membrane is attached below to the upper border of the thyroid cartilage and to the front of its superior cornu, ...

https://en.wikipedia.org/wiki/Thyrohyoid_membrane

An acoustic membrane is a thin layer that vibrates and is used in acoustics to produce or transfer sound, such as a drum, ... Membranophone Vibrations of a circular membrane v t e (Articles lacking sources from August 2011, All articles lacking sources ...

https://en.wikipedia.org/wiki/Acoustic_membrane

In this system a semipermeable membrane separates two solutions of different concentration of the same solute. If the membrane ... The movements of most solutes through the membrane are mediated by membrane transport proteins which are specialized to varying ... The regulation of passage through the membrane is due to selective membrane permeability - a characteristic of biological ... The macromolecules on one side of the membrane can bond preferentially to a certain component of the membrane or chemically ...

https://en.wikipedia.org/wiki/Membrane_transport

A Cargile membrane was a sterile membrane made from the peritoneum of the ox, and was the first commercially available adhesion ... Craig, A. B.; Ellis, A. G. (June 1905). "I. An Experimental and Histological Study of Cargile Membrane: With Reference to (1) ... It was designed primarily to cover surfaces over which peritoneum has been removed, especially where a sterile membrane would ... Some uses of Cargile membrane - Red Cross Notes. Johnson & Johnson. 1904. pp. 70-. "Find A Grave". Archived from the original ...

https://en.wikipedia.org/wiki/Cargile_membrane

... in a bird egg (7) Vitelline membrane in an amphibian egg (2) Vitelline membrane in a fish egg (A) Formation ... The vitelline membrane or vitelline envelope is a structure surrounding the outer surface of the plasma membrane of an ovum ( ... The innermost membrane of all animal eggs except some cnidarians is called the vitelline membrane. Some invertebrates and some ... Frog and bird eggs have a very thin vitelline membrane which are surrounded by either a jelly layer (frogs) or other membranes ...

https://en.wikipedia.org/wiki/Vitelline_membrane

... may refer to: External limiting membrane Internal limiting membrane Glial-limiting membrane This ... disambiguation page lists articles associated with the title Limiting membrane. If an internal link led you here, you may wish ...

https://en.wikipedia.org/wiki/Limiting_membrane

The basement membrane is also essential for angiogenesis (development of new blood vessels). Basement membrane proteins have ... The most notable examples of basement membranes is the glomerular basement membrane of the kidney, by the fusion of the basal ... other roles for basement membrane include blood filtration and muscle homeostasis. Fractones may be a type of basement membrane ... The basement membrane is a thin, pliable sheet-like type of extracellular matrix that provides cell and tissue support and acts ...

https://en.wikipedia.org/wiki/Basement_membrane

Impermeable' is essential here to distinguish nanotube membrane with traditional, well known porous membranes. Fluids and gas ... Nanotube membranes are either a single, open-ended nanotube(CNT) or a film composed of an array of nanotubes that are oriented ... Soon after, ensemble membranes consisting of multi-walled and double-walled carbon nanotubes were fabricated and studied. It ... Transport of polystyrene particles (60 and 100 nm diameter) through single-tube membranes (150 nm) was reported in 2000. ...

https://en.wikipedia.org/wiki/Nanotube_membrane

Chemical reactors making use of membranes are usually referred to as membrane reactors. The membrane can be used for different ... A membrane reactor is a physical device that combines a chemical conversion process with a membrane separation process to add ... For dense membranes the separation is governed by the difference of the chemical potential of the components in the membrane. ... The membrane allows the uniform distribution of oxygen as the driving force for the permeation of oxygen through the membrane ...

https://en.wikipedia.org/wiki/Membrane_reactor

... s are a family of biological membrane proteins which allow the passive movement of ions (ion channels), water ( ... A hemichannel is a membrane channel made up of six subunits. A hemichannel is defined as one-half of a gap junction channel. ... Baroja-Mazo A, Barberà-Cremades M, Pelegrín P (January 2013). "The participation of plasma membrane hemichannels to purinergic ... See Glossary, under "membrane channels". (Membrane biology). ... or other solutes to passively pass through the membrane down ...

https://en.wikipedia.org/wiki/Membrane_channel

Both obturator muscles are connected with this membrane. Hip joint. Lateral view. Obturator membrane This article incorporates ... The membrane is attached to the sharp margin of the obturator foramen except at its lower lateral angle, where it is fixed to ... The obturator membrane is a thin fibrous sheet, which almost completely closes the obturator foramen. Its fibers are arranged ...

https://en.wikipedia.org/wiki/Obturator_membrane

The outer membrane is permeable to most ions and metabolites, but the inner membrane of the chloroplast is highly specialised ... The two envelope membranes are separated by a gap of 10-20 nm, called the intermembrane space. Within the envelope membranes, ... Each of the envelope membranes is a lipid bilayer that is between 6 and 8 nm thick. The lipid composition of the outer membrane ... The thylakoid membrane is quite similar in lipid composition to the inner envelope membrane, containing 78% galactolipids, 15.5 ...

https://en.wikipedia.org/wiki/Chloroplast_membrane

Membrane+dipeptidase at the US National Library of Medicine Medical Subject Headings (MeSH) Portal: Biology (EC 3.4.13). ... Membrane dipeptidase (EC 3.4.13.19, renal dipeptidase, dehydropeptidase I (DPH I), dipeptidase, aminodipeptidase, dipeptide ... This membrane-bound, zinc enzyme has broad specificity. Inhibitors include bestatin and cilastatin. Dipeptidase 1 (DPEP1) ...

https://en.wikipedia.org/wiki/Membrane_dipeptidase

The perineal membrane is an anatomical term for a fibrous membrane in the perineum. The term "inferior fascia of urogenital ... The perineal membrane is triangular in shape. It attaches to both ischiopubic rami of the pelvis. It also attaches to the ... diaphragm", used in older texts, is considered equivalent to the perineal membrane. It is the superior border of the ...

https://en.wikipedia.org/wiki/Perineal_membrane

... can refer to: Anterior atlantooccipital membrane Posterior atlantooccipital membrane This ... disambiguation page lists articles associated with the title Atlantooccipital membrane. If an internal link led you here, you ...

https://en.wikipedia.org/wiki/Atlantooccipital_membrane

... may refer to: The periodontal ligament (PDL), largely referred to as the periodontal membrane outside of ... This disambiguation page lists articles associated with the title Periodontal membrane. If an internal link led you here, you ... the United States An artificial periodontal membrane, used to block the spread of growing epithelium after periodontal surgery ...

https://en.wikipedia.org/wiki/Periodontal_membrane

... may refer to: M-theory, a theory in physics that unifies all of the consistent versions of superstring theory ... Membrane theory of shells, describes the mechanical properties of shells Membrane potential, a theory that explained the ... of nerve and muscle as a diffusion potential This disambiguation page lists articles associated with the title Membrane Theory ...

https://en.wikipedia.org/wiki/Membrane_Theory

Bio-Membrane is classified in two categories, synthetic membrane and natural membrane. synthetic membranes further classified ... Organic membrane sub classified polymeric membranes and inorganic membrane sub classified ceramic polymers. Green membrane or ... A biomass-based membrane is a membrane made from organic materials such as plant fibers. These membranes are often used in ... Biomass Membrane gas separation more effective then commercial membrane. Membrane application in hemodialysis is a process of ...

https://en.wikipedia.org/wiki/Membrane_technology

A biological membrane, biomembrane or cell membrane is a selectively permeable membrane that separates the interior of a cell ... such as mucous membranes, basement membranes, and serous membranes. The lipid bilayer consists of two layers- an outer leaflet ... For all cells, membrane fluidity is important for many reasons. It enables membrane proteins to diffuse rapidly in the plane of ... It allows membranes to fuse with one another and mix their molecules, and it ensures that membrane molecules are distributed ...

https://en.wikipedia.org/wiki/Biological_membrane

EMBL-EBI

https://www.ebi.ac.uk/QuickGO/term/GO:0005741

... was valued at US$ 15.30 Bn. in 2021 and the market size is estimated to grow at a CAGR of 7.25%. ... Membrane Filtration Market was valued at US$ 15.30 Bn. in 2021. The Global Membrane Filtration Market size is estimated to grow ... North America Membrane Filtration Market, by Country (2021-2029) • United States • Canada • Mexico 6. European Membrane ... Membrane Filtration Market Overview:. Market growth of Membrane Filtration is growing rapidly because of a few factors, the ...

https://www.maximizemarketresearch.com/market-report/membrane-filtration-market/11166/

We found these membranes could remove > 99.99% of 25-250 nm diameter SiC nanoparticles dispersed in ethanol, ... Field trials on dirty canal water showed these composite membranes to remove aluminium to a level × 10 below the EU limit for ... In filtration tests, while adding ~ 10 wt% graphene/Teflon to the glass fibre membrane decreased the flow rate by × 100, ... Annealing the resultant composites leads to coalescence of the Teflon, resulting in very stable membranes with significantly ...

https://www.nature.com/articles/s41598-020-78091-x?error=cookies_not_supported&code=6c5d8e16-16f3-4c19-8d42-9c295c627f6c

MEMBRANE ACOUSTIC PANEL - Designer Sound absorbing room divider from OFFECCT ✓ all information ✓ high-resolution images ✓ CADs ... The components of Membrane will be produced in a mixture of recycled felt and plastic. It marks a successful first fusion ... Membrane filters sound waves and makes the sound in a room more balanced. One kit consists of 24 acoustic pieces including ... The design for Membrane derives from David Trubridges signature seed system in which a product is entirely made out of several ...

https://www.architonic.com/en/product/offecct-membrane-acoustic-panel/1356141

The user will learn about membrane proteins, their structures, and how they contribute towards cell function. ... It gives an overview of membrane proteins, with particular emphasis on peripheral and integral proteins. ...

https://www.merlot.org/merlot/viewCompositeReview.htm?id=1379718

In most cases, these membranes rupture during labor or within 24 hours before starting labor. Premature rupture ... This membrane is called the amniotic sac.. Often, the membranes rupture (break) during labor. This is often called "when the ... Premature rupture of the membranes (PROM) is said to occur when the membranes break before the 37th week of pregnancy. ... Some of the fluid is lost when the membranes break. The membranes may continue to leak. ...

https://medlineplus.gov/ency/patientinstructions/000512.htm

NC membranes are thin (150 um) sheets of NC polymer that have pores of highly controlled size. Typical is use of NC membranes ... Sterilization of NC membranes is achieved at 121 C (250 F), 1 bar for 15 minutes. As an added precaution, membranes can be ... NC membranes are manufactured by dissolving cellulose nitrate or a mixture of cellulose nitrate and cellulose acetate in a ... Radioactive membranes should be disposed of in an approved sanitary landfill established for radioactive waste. As an added ...

https://www.cdc.gov/mmwr/preview/mmwrhtml/00000630.htm

The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an ... The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an ... temperature to form a solid membrane. Solid lithium ion electrolyte membranes manufactured according to these methods are also ... Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes. United States: N. p., 2012. ...

https://www.osti.gov/doepatents/biblio/1078316

Extracorporeal Membrane Oxygenation as a Bridge to Surgical Repair of Postinfarct Ventricular Septal Defect : ASAIO Journal. ... Extracorporeal Membrane Oxygenation as a Bridge to Surgical Repair of Postinfarct Ventricular Septal Defect. Doi, Atsuo*; Negri ... Extracorporeal Membrane Oxygenation as a Bridge to Surgical Repair of Postinfarct Ventricular Septal Defect ... Extracorporeal Membrane Oxygenation Blood Flow and Blood Recirculation Compromise Thermodilution-Based Measurements of Cardiac ...

https://journals.lww.com/asaiojournal/Abstract/2023/01000/Extracorporeal_Membrane_Oxygenation_as_a_Bridge_to.20.aspx?context=FeaturedArticles&collectionId=4

Introduction to ECMO The term extracorporeal membrane oxygenation (ECMO) was initially used to describe long-term ... encoded search term (Pediatric Extracorporeal Membrane Oxygenation) and Pediatric Extracorporeal Membrane Oxygenation What to ... Pediatric Extracorporeal Membrane Oxygenation. Updated: Dec 21, 2017 * Author: Edwin Rodriguez-Cruz, MD; Chief Editor: Stuart ... Is extracorporeal membrane oxygenation for a neonate ever ethically obligatory?. J Pediatr. 2017 Dec 13. [QxMD MEDLINE Link]. ...

https://www.medscape.com/answers/1818617-182434/how-are-infections-controlled-in-pediatric-patients-on-ecmo

Delta Membrane Systems Ltd is the leading Type C Cavity Drain Membrane Manufacturer in the United Kingdom. Delta provides a ... We also supply ground gas protection membranes protecting structures from harmful ground gases such as radon, carbon dioxide, ...

https://www.deltamembranes.com/login/?requires_login=1&redirect_to=https://www.deltamembranes.com/product-categories/bespoke-sump-pumps

... Popp, Raymond Arthur ... Popp, Raymond Arthur (1958)."Comparative metabolism of blastocysts, extraembryonic membranes, and uterine endometrium of the ...

https://deepblue.lib.umich.edu/handle/2027.42/38048

Purchase Hollow Fiber Membranes - 1st Edition. Print Book & E-Book. ISBN 9780128218761, 9780128218914 ... Membrane fabrication and applications of PI hollow fiber membranes Section V Applications of hollow fiber membranes 18. ... Membrane fabrication and applications of PSf/PES/PPSU hollow fiber membranes 15. Polyvinylidene fluoride (PVDF) Membrane ... Development of membrane technology and comparison between hollow fiber membranes and other membrane configurations 2. Polymeric ...

https://www.elsevier.com/books/hollow-fiber-membranes/chung/978-0-12-821876-1

What is a membrane?. A membrane is a filter with small pores that let some of the substances through and others not. It looks ... The term membrane is derived partly from the French membrane (web in a plant / thin smooth skin around organs) and partly from ... The roadshow Polymer Membranes shows two interesting projects from the research of the group Membrane Materials and Processes ( ... The membrane allows in this case no water, but salt ions to diffuse into the fresh water from the salt sea water. And the ...

https://www.tue.nl/en/our-university/about-the-university/sustainability/go-green-office/roadshow-polymer-membranes/

At just a fraction of a millimetre thick and held under tension, the membrane is perfectly adapted to transmit even the ... The eardrum, or tympanic membrane, forms the interface between the outside world and the delicate bony structures of the middle ... are likely to have a higher prevalence of tympanic membrane perforations (T. S. Ibekwe et al. Otol. Neurotol. 28, 348-352; 2007 ... Holmes, D. Eardrum regeneration: membrane repair. Nature 546, S5 (2017). https://doi.org/10.1038/546S5a ...

https://www.nature.com/articles/546S5a?error=cookies_not_supported&code=febb68d7-4755-4fe5-9042-127cb5ea98d7

Preterm Rupture of Membranes. Preterm Rupture of Membranes "Mid-trimester Prolonged Rupture of Membranes" and "Delayed Interval ... Mid-trimester Prolonged Rupture of Membranes 2017 Notification Form. Delayed Interval Delivery in Premature Multiple Pregnancy ... "Mid-trimester Prolonged Rupture of Membranes" and "Delayed Interval Delivery in Premature Multiple Pregnancy". ...

https://www.ucc.ie/en/npec/npec-clinical-audits/mt_promanddid_pmp/

Membranes, an international, peer-reviewed Open Access journal. ... Submit to Membranes Review for Membranes Journal Menu. ► ▼ ... Membrane-based processes are attractive for treating oily wastewaters. However, membrane fouling due to the deposition of oil ... Membrane-based processes are attractive for treating oily wastewaters. However, membrane fouling due to the deposition of oil ... For the fouled membrane, the surface of the contaminated membrane was covered by macromolecular contaminants, causing the ...

https://www.mdpi.com/2077-0375/9/12

The Escherichia coli outer membrane protein OmpA acquires secondary structure prior to its integration into the membrane. ... Almost all proteins that reside in the outer membrane (OM) of Gram-negative bacteria contain a membrane-spanning segment that ... The YidC family of proteins are membrane insertases that catalyze the translocation of the periplasmic domain of membrane ... The Na+,K+-ATPase generates electrochemical gradients of Na+ and K+ across the plasma membrane via a functional cycle that ...

https://www.jbc.org/Membrane-Biology?startPage=0&pageSize=25

The roof is a white EPDM membrane. Id like to install gutters to direct water runoff. The facia boards are only 4 high and ... put back of gutter behind membrane and drip edge? - I recently bought a 60s flat-roofed house that doesnt have any gutters. ... roof membrane back of gutter terminal bar/drip edge. That way the roof membrane is pressed flat against the fascia and ... It seems to me that maybe I could just slip the back edge of the gutter behind the membrane and drip edge so that water runs ...

https://www.doityourself.com/forum/roofing-gutters-all-waterproofing-anywhere/594222-flat-roof-gutters-put-back-gutter-behind-membrane-drip-edge.html

Contact information of the Inorganic Membranes group at the University of Twente ... Inorganic Membranes Group. Faculty of Science & Technology. University of Twente. P.O. Box 217. 7500 AE Enschede. The ...

https://www.utwente.nl/en/tnw/im/contact/

FUJIFILM is a membrane supplier, and delivers the components to system builders and end users. Read here more. ... FUJIFILM is developing and producing unique membranes to filter microscopic particles out of gas or liquids. For example, these ...

https://www.fujifilm.com/ef/en/what-we-do/membranes

The tectorial membrane is above the hair cells within the ear. The membrane is joined to the bony shelf of the cochlea and ...

https://www.innerbody.com/image_nerv14/nerv180.html

The composite membranes exhibited strong antimicrobial activity against Gram-negative and Gram-positive bacteria. ... Antimicrobial bacterial cellulose-silver nanoparticles composite membranes have been obtained by ,i,“in situ”,/i, ... BC-Ag-TEA 1 M membrane, Figure 2(b) shows well dispersed spherical silver particles (white spots) attached to the BC membrane ... Bacterial Cellulose Membranes. Never dried bacterial cellulose (4 mm thick) membranes were supplied from Fibrocel-Produtos ...

https://www.hindawi.com/journals/jnm/2011/721631/

... even the membrane bound nuclei , which house the genetic instructions for life that are written in our DNA, begin to show ... Tags: Aging, B Cell, Brain, Cell, Cell Cycle, Cell Division, Cell Nucleus, Cytoplasm, Daughter Cell, DNA, Genetic, Membrane, ... If those gated holes are lost, the membrane collapses, he said. " How do you replace a bridge while transport is happening?" he ... As parts of us age, even the membrane bound nuclei , which house the genetic instructions for life that are "written" in our ...

https://www.news-medical.net/news/2009/01/23/45236.aspx

3M™ Betafine™ XL Series Filter Cartridge, XL10PP010B2K, 10 in, 1 μ, 30/Case 3M™ Betafine™ XL Series Filter Cartridge, XL20PP010B0A, 20 in, 1 μ, 15/Case 3M™ Betafine™ PPG Series Filter Cartridge, PPG020B01BA, 10 in, 0.2 μ, 6/Case 3M™ Betafine™ XL Series Filter Cartridge, XL10PP050DC, 10 in, 5 μ, 30/Case 3M™ High Flow Series Filter Cartridge, HF60PP005A01, 60 in, 5 μ, Silicone, 1/Case 3M™ LifeASSURE™ BNA Series Filter Cartridge, BNA045F04BA, 40 in, 0.45 μ, 6/Case 3M™ Betafine™ XL Series Filter Cartridge, XL20PP050B0C, 20 in, 5 μ, 15/Case 3M™ Betafine™ XL Series Filter Cartridge, XL30PP005B2A, 30 in, 0.5 μ, 15/Case 3M™ LifeASSURE™ PDA Series Filter Cartridge, PDA020F50JA, 5 in, 0.2 µ, 1/Case 3M™ LifeASSURE™ BLA Series Filter Cartridge, BLA020B04BA, 40 in, 0.2 μ, 6/Case 3M™ Betafine™ XL Series Filter Cartridge, XL20PP005C2A, 20 in, 0.5 μ, 15/Case 3M™ High Flow Series Filter Cartridge, HF60PP002D01, 60 in, 2 μ, Nitrile, 1/Case 3M™ Betafine™ ...

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Integral Molecular has developed the Membrane Proteome Array, a high-throughput flow cytometry platform. ... To zero in on membrane protein antibody targets, ... The Membrane Proteome Array. To address the need for antibody ... The MPA makes use of the largest membrane protein library yet assembled, representing over 4,500 unique human membrane proteins ... Figure 3. Integral Moleculars Membrane Proteome Array was used to identify human membrane proteins that act as receptors for ...

https://www.genengnews.com/magazine/screening-the-membrane-proteome/

All the latest membrane separation news, videos, and more from the worlds leading engineering magazine. ... Nanotube Membrane Could Revolutionize Osmotic Power Membrane could boost efficiency of todays osmotic systems 1000 times. ... membrane separation News & Articles. Showing 3 posts that have the tag "membrane-separation" ... Graphene-based Gas Membranes Promise Reduced Carbon Dioxide Emissions For first time physical experiments show that graphene ...

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... This 150 gpd membrane fits most all RO systems. ... This thin film membrane is custom rolled to our specifications. All I can say if you love the membrane we have been selling for ... 150GPD Membrane and Flow restrictor. This 150 gpd membrane fits most all RO systems. It is a thin film composite mambrane with ... This membrane is high output with slightly lower rejection. NEW 150 gallon per day membrane. It can produce up 150 gallon per ...

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We study membrane materials for power-to-X technologies in order to elucidate their atomic structures, defects and transport ... Gas separation membranes for power plant and chemical engineering applications are investigated with respect to their ...

https://www.fz-juelich.de/en/er-c/er-c-2/research/topics/gas-separation-membranes-1

Here, we map the electrical potentials along the membrane of di … ... We find that the intramembrane potential gradient is indeed more positive in the membranes of neurites than in the membranes of ... Distinct electric potentials in soma and neurite membranes Neuron. 1994 Nov;13(5):1187-93. doi: 10.1016/0896-6273(94)90056-6. ... This is not attributable to differences in ion conductances or surface charge densities between the membranes of neurites and ...

https://pubmed.ncbi.nlm.nih.gov/7946355/

Eliminate the risk to contamination with our reverse osmosis membranes for RO water systems. (waterfilters.net)
INDION 2814 Alkaline RO Membrane Cleaner is a specially formulated cleaner for removing heavy metal fouling, bio-foulants, slime, polysilicic scales and other colloidal/particulate based foulants from reverse osmosis membranes. (jojomarketing.ae)

The largest share of 42% held by the membrane filtration market in the year 2021 is Reverse Osmosis segment. (maximizemarketresearch.com)
The segment which held the largest share of 39% of the membrane filtration market is water and wastewater treatment in the year 2021. (maximizemarketresearch.com)
Global HEPA Filter Membranes Market Size was estimated at USD 495.2 million in 2021 and is projected to reach USD 754.5 million by 2028, exhibiting a CAGR of 6.2% during the forecast period. (alpenhornnews.com)

When the water breaks early, it is called premature rupture of membranes (PROM). (medlineplus.gov)
If the water breaks before the 37th week of pregnancy, it is called preterm premature rupture of membranes (PPROM). (medlineplus.gov)

The goal of treatment in mucous membrane pemphigoid (MMP) (cicatricial pemphigoid) is to suppress extensive blister formation, promote healing, and prevent scarring. (medscape.com)
Patients with mucous membrane pemphigoid (MMP) and ocular involvement require ongoing ophthalmologic care. (medscape.com)
The transfer of epithelial stem cells restored useful vision in these patients, including several patients with ocular mucous membrane pemphigoid. (medscape.com)
Care should be taken to control the inflammatory component of the disease before and immediately after surgery because patients with mucous membrane pemphigoid frequently experience flare-ups after surgery. (medscape.com)
The management of mucous membrane pemphigoid (MMP) requires a coordinated team approach. (medscape.com)
The first international consensus on mucous membrane pemphigoid: definition, diagnostic criteria, pathogenic factors, medical treatment, and prognostic indicators. (medscape.com)
Mucous membrane pemphigoid (MMP), also known as cicatricial pemphigoid, refers to a group of rare chronic autoimmune blistering diseases that predominately affect the mucous membranes, including the conjunctiva, and occasionally the skin. (medscape.com)
The first international consensus on mucous membrane pemphigoid was published in 2002. (medscape.com)
See the illustration below depicting ocular mucous membrane pemphigoid. (medscape.com)
Ocular manifestations of cicatricial pemphigoid (mucous membrane pemphigoid) include symblepharon, demonstrated in this photograph by the tethering of the lower lid to the cornea. (medscape.com)
Classification of mucous membrane pemphigoid patients has been difficult because some patients with other autoimmune blistering diseases, including bullous pemphigoid (BP), epidermolysis bullosa acquisita (EBA),and anti-p200 pemphigoid, may have mucosal involvement. (medscape.com)
By direct immunofluorescence (DIF) study, antibodies bound in a linear band at the epidermal-dermal junction have been found in patients with mucous membrane pemphigoid (MMP), as depicted below. (medscape.com)
Different epithelial membrane zone components have been recognized by antibodies in patients with mucous membrane pemphigoid, including BP antigens 1 and 2 (BP230 and BP180), laminin-332, laminin-311, type VII collagen, b4 integrin subunit, and antigens with unknown identities (a 45-kd protein, uncein, a 168-kd epithelial protein, and a 120-kd epithelial protein). (medscape.com)
Mucous membrane pemphigoid (MMP) is an autoimmune blistering disease associated with autoantibodies directed against basement membrane zone target antigens. (medscape.com)
The two major antigens associated with mucous membrane pemphigoid are BP180 and laminin-332. (medscape.com)
Patients with clinical features of mucous membrane pemphigoid may have antibodies directed against BP230 or type VII collagen. (medscape.com)
Patients with mucous membrane pemphigoid react with epitopes on BP180 distinct from those associated with BP and linear IgA bullous dermatosis, particularly the C-terminal of the protein. (medscape.com)
A subset of patients with mucous membrane pemphigoid reacts with laminin-332. (medscape.com)
Laminin-332 contains disulfide-linked alpha, beta, and gamma chains, of which the alpha subunit is the major site of mucous membrane pemphigoid reactivity. (medscape.com)
After initiating the systemic corticosteroid therapy, the Mucous Membrane Pemphigoid (MMP) in a 9-year-old-boy suc- patient showed total regression of the lesions, and no indication cessfully treated with low doses of systemic corticosteroid. (bvsalud.org)
Oral manifestation of MMP is extremely rare in children5, with Mucous membrane pemphigoid (MMP) constitutes a group just a few reports in the literature. (bvsalud.org)

The roadshow Polymer Membranes shows two interesting projects from the research of the group Membrane Materials and Processes (MM/P). Kitty Nijmeijer and Zandrie Borneman manage some fifteen applied research projects that focuses on the creation, characterization, and application of membranes for a variety of applications. (tue.nl)
The paper, " An Integrated Materials Approach to Ultrapermeable and Ultraselective CO 2 Polymer Membranes ," is published in the journal Science . (eurekalert.org)

We commenced a protocol of veno-arterial extracorporeal membrane oxygenation (VA ECMO) for those patients who present in cardiogenic shock with the aim to improve end-organ function before definitive surgical repair to reduce postoperative mortality. (lww.com)
The term extracorporeal membrane oxygenation (ECMO) was initially used to describe long-term extracorporeal support that focused on the function of oxygenation. (medscape.com)
Extracorporeal membrane oxygenation (ECMO) system. (medscape.com)
Extracorporeal membrane oxygenation (ECMO) is an established therapeutic option for patients with medically refractory cardiogenic or respiratory failure. (cdc.gov)
Extracorporeal Membrane Oxygenation (ECMO) is a topic covered in the Adult and Pediatric Cardiac . (sts.org)
Extracorporeal membrane oxygenation (ECMO) can provide lifesaving respiratory and cardiac support for patients when maximal conventional therapy is failing. (sts.org)

Extracorporeal Membrane Oxygenation as a Bridge to Surgical. (lww.com)
A diagram of extracorporeal membrane oxygenation is shown below. (medscape.com)
In 1970, Baffes et al reported the successful use of extracorporeal membrane oxygenation as support in infants with congenital heart defects who were undergoing cardiac surgery. (medscape.com)

And we've demonstrated that we can vastly improve the selectivity of membranes to remove CO 2 while retaining relatively high CO 2 permeability. (eurekalert.org)
A longstanding challenge for such membranes has been a trade-off between permeability and selectivity. (eurekalert.org)
The higher the permeability, the more quickly you can move gas through the membrane. (eurekalert.org)
But when permeability goes up, selectivity goes down - meaning that nitrogen, or other constituents, also pass through the membrane quickly - reducing the ratio of CO 2 to other gases in the mixture. (eurekalert.org)
Practically viable solutions for AEMFC design will most likely require both advanced material design (to tune and control the water diffusivity and hydraulic permeability across the membrane and the hydrophobic/hydrophilic character of the gas diffusion and electrode layers on both sides) as well as innovative stack-level or system-level design (to provide additional routes for water transport from the anode to the cathode). (chalmers.se)
Upon incorporating 4 mg/m2 of liposomes, the best-performing S4-a membrane is able to achieve 27% higher water permeability than the liposome-free membrane, demonstrating a permeability of 3.24 L/m2·h·bar along with 99.3% NaCl rejection for seawater desalination. (ntu.edu.sg)
These PA structural changes of the AQP-based membrane were found to contribute over 70% to the water permeability increase via comparing the separation performance of the membranes prepared with liposome , detergent , and proteoliposome, respectively, and one proteoliposome-ruptured membrane . (bvsalud.org)

EPDM waterproof membrane is made from ethylene propylene diene monomer (EPDM), adding into some chemical auxiliaries, for example, carbon black, nanophase modifier, plasticizer, vulcanization accelerator and others, it is one kind of polymer waterproof membrane with excellent performance elasticity. (bestcon-group.com)

Journal of Membrane Science 409-410 : 34-43. (nus.edu.sg)

Timely diagnosis of ruptured fetal membranes during the pregnancy is important. (who.int)

Comparative metabolism of blastocysts, extraembryonic membranes, and uterine endometrium of the mouse This investigation was supported in part by a Horace H. Rackham Graduate Student Research Grant No. 143. (umich.edu)

The roof is a white EPDM membrane. (doityourself.com)
The qualified roofing experts at The Home Builder's Network, Inc. provide knowledgeable EPDM material roofing recommendations in addition to licensed and insured white membrane roofing installation that is fitted to your existing roof system at a fraction of the cost of complete roof replacement. (myhomebuildersnetwork.com)
Energy efficient singly ply EPDM white membrane roofing is fully adhered to your existing roof or mechanically fastened or ballasted by our skilled and experienced roofing technicians. (myhomebuildersnetwork.com)
One of the easiest roofing systems to maintain and repair, the specific characteristics of an EPDM white membrane roofing systems allow it to stand up exceptionally well to years of exposure to harsh weather conditions and fluctuations temperatures with very little maintenance requirements. (myhomebuildersnetwork.com)

The scientists engineered a microfluidic device containing an array of microscopic cups, each trapping a single droplet of water bathed in oil and lipids, the molecules that make up cellular membranes. (scripps.edu)
In this chapter we consider the structure and organization of the two main constituents of biological membranes-the lipids and the membrane proteins. (nih.gov)

The development of low-cost ultrafiltration membranes with relatively high flow rate and selectivity is an important goal which could improve access to clean water in the developing world. (nature.com)
In filtration tests, while adding ~ 10 wt% graphene/Teflon to the glass fibre membrane decreased the flow rate by × 100, the selectivity improved by × 10 3 compared to the neat glass fibre membrane. (nature.com)
We then engineered the surface of these membranes to improve selectivity. (eurekalert.org)
Zr-fum67-mes33-fcu-MOF membranes exhibit record -high nitrogen / methane selectivity and nitrogen permeance under practical pressures up to 50 bar, removing both carbon dioxide and nitrogen from natural gas . (bvsalud.org)
This study reveals that the changed morphology dominates the performance improvement of the AQP-based PA membrane and well explains why the actual AQP-based PA membranes cannot acquire the theoretical water / salt selectivity of a biomimetic AQP membrane , deepening our understanding of the AQP-based membranes . (bvsalud.org)

Methods: Sputum samples were collected from 156 workers employed in 15 cotton textile mills, and expression of epithelial membrane antigen (‎EMA)‎ and cytokeratin (‎CK)‎ marker proteins was investigated. (who.int)
Sections (5 µm thick) of the paraffin blocks were cut using a microtome, and stained with immunohistochemical molecular markers for epithelial membrane antigen (EMA) or cytokeratin (CK). (who.int)
Systemic corticosteroids are usually ear deposition of IgG, IgA, or C3 along the epithelial basement avoided in treating young patients having MMP with oral le- membrane zone (BMZ)1, resulting from the formation of anti- sions, because of their serious side effects. (bvsalud.org)

In most cases, these membranes rupture during labor or within 24 hours before starting labor. (medlineplus.gov)
Premature rupture of the membranes (PROM) is said to occur when the membranes break before the 37th week of pregnancy. (medlineplus.gov)
Often, the membranes rupture (break) during labor. (medlineplus.gov)
Tympanic membrane perforation (also called ruptured eardrum) is a tear or rupture of the skin that separates the ear canal from the middle ear (eardrum). (childrens.com)
An untreated tympanic membrane perforation or an extremely violent rupture can also lead to complications like middle ear infections (bacteria enters through the tear) or development of a cholesteatoma (a cyst in the middle ear). (childrens.com)

2002. Chapter 10, Membrane Structure. (nih.gov)

IMSEAR at SEARO: Ultrafiltration membranes in biotechnology. (who.int)
Ultrafiltration membranes in biotechnology. (who.int)

Special proteins inserted in cellular membranes create pores that permit the passage of molecules across them. (nih.gov)

Biocompatibility and biodegradation of a native porcine pericardium membrane: results of in vitro and in vivo examinations. (straumann.com)

Membrane Filtration Market was valued at US$ 15.30 Bn. (maximizemarketresearch.com)
The Global Membrane Filtration Market size is estimated to grow at a CAGR of 7.25% over the forecast period. (maximizemarketresearch.com)
Market growth of Membrane Filtration is growing rapidly because of a few factors, the rapidly growing dairy industries, regulations for water safety and filtration, and increasing demand for premium products. (maximizemarketresearch.com)
Membrane filtration is broadly used for removing microorganisms, bacteria, and organic material from the water. (maximizemarketresearch.com)
Also, the government regulations for water purification are also contributing to the demand for the membrane filtration market. (maximizemarketresearch.com)
Low energy costs and increasing demand for industrial filtration for better processing are driving the membrane filtration market. (maximizemarketresearch.com)
Membrane filtration is also used in large-scale industrial use. (maximizemarketresearch.com)
So, these are the factors that drive the market growth of the membrane filtration market. (maximizemarketresearch.com)
Cost-reducing properties of the membrane filtration along with the rising demand for good quality membrane filtered food have boosted the market growth of the membrane filtration market across the globe. (maximizemarketresearch.com)
the increased adoption of this technology by government bodies to ensure access to safe and clean water is contributing to the rising demand for reverse osmosis in the membrane filtration market. (maximizemarketresearch.com)
Based on the Application , the Membrane Filtration Market is segmented into Water and wastewater treatment, Dairy Drinks and concentrates, Food and Beverages, Winery. (maximizemarketresearch.com)
Typical is use of NC membranes with pore sizes of 0.45 um suitable for capturing bacteria in a filtration process. (cdc.gov)
The researchers are also interested in exploring other applications, such as whether the new membrane technology could be used in biomedical ventilator devices or filtration devices in the aquaculture sector. (eurekalert.org)

In a 2016 preferred practice guideline for epiretinal membranes, the authors reported that, over a 5-year period, 29% of epiretinal membranes progressed, 26% regressed, and 39% remained stable. (medscape.com)

Cell membranes are crucial to the life of the cell. (nih.gov)
Cell membranes are dynamic, fluid structures, and most of their molecules are able to move about in the plane of the membrane. (nih.gov)
The functions of cell membranes are considered in later chapters. (nih.gov)
Voiceover] Let's explore the Fluid Mosaic Model of cell membranes. (khanacademy.org)

Field trials on dirty canal water showed these composite membranes to remove aluminium to a level × 10 below the EU limit for drinking water and reduce iron and bacteria contents to below detectable levels. (nature.com)
Antimicrobial bacterial cellulose-silver nanoparticles composite membranes have been obtained by "in situ" preparation of Ag nanoparticles from hydrolytic decomposition of silver nitrate solution using triethanolamine as reducing and complexing agent. (hindawi.com)
The composite membranes exhibited strong antimicrobial activity against Gram-negative and Gram-positive bacteria. (hindawi.com)
Antimicrobial tests for the BC-silver nanoparticles composite membranes were also considered. (hindawi.com)

It gives an overview of membrane proteins, with particular emphasis on peripheral and integral proteins. (merlot.org)
The user will learn about membrane proteins, their structures, and how they contribute towards cell function. (merlot.org)
The lack of suitable methods to identify the targets of functional antibodies and ligands, particularly membrane proteins (which are the targets for more than 60% of FDA-approved antibody therapies), has led to freezers full of potential therapeutic candidates with no known target. (genengnews.com)
The MPA is a high-throughput cell-based platform for identifying the targets of orphan antibodies and other ligands that bind to membrane proteins ( Figure 1 ). (genengnews.com)
Membrane proteins account for roughly a quarter of all the proteins encoded by the human genome and often fold into conformationally complex structures that are difficult to retain outside of the cell. (genengnews.com)
The key feature of the MPA is that human membrane proteins are individually expressed and tested in their native state directly within human cells, thereby retaining their structural integrity and native post-translational modifications. (genengnews.com)
The MPA makes use of the largest membrane protein library yet assembled, representing over 4,500 unique human membrane proteins. (genengnews.com)
Integral Molecular has leveraged its 15 years of experience working on membrane proteins by including optimized variants of the most recalcitrant membrane proteins, overcoming challenges with their expression and trafficking. (genengnews.com)
Membrane proteins are expressed in human cells within 384-well microplates, and ligand binding is detected by flow cytometry, allowing sensitive detection of both specific and off-target binding. (genengnews.com)
In the course of developing antibodies against membrane proteins, Integral Mo lecular has identified hundreds of orphan antibodies that are highly reactive with human membrane proteins but whose specificities are not yet known. (genengnews.com)
Ion gradients across membranes, established by the activities of specialized membrane proteins, can be used to synthesize ATP, to drive the transmembrane movement of selected solutes, or, in nerve and muscle cells, to produce and transmit electrical signals. (nih.gov)
In the plasma membrane, some proteins serve as structural links that connect the cytoskeleton through the lipid bilayer to either the extracellular matrix or an adjacent cell, while others serve as receptors to detect and transduce chemical signals in the cell's environment. (nih.gov)
As would be expected, it takes many different membrane proteins to enable a cell to function and interact with its environment. (nih.gov)
In fact, it is estimated that about 30% of the proteins that are encoded in an animal cell's genome are membrane proteins. (nih.gov)
The fluid mosaic model describes the cell membrane as a tapestry of several types of molecules (phospholipids, cholesterols, and proteins) that are constantly moving. (khanacademy.org)

MM/P is doing research into the application of polymeric membranes in water to purify waste water and re-use of water. (tue.nl)
The test rig is a universal laboratory scale facility which can take any type of membranes of different materials (flat sheet, hollow fibre, polymeric, inorganic, etc.), applicable for various mild and harsh conditions, e.g. for natural gas sweetening as well as flue gas CO 2 separation. (sintef.no)

If the process of manufacturing of membrane is not precisely maintained, the membrane with big pores size may disturb the final result and give poor performance. (maximizemarketresearch.com)
NC membranes are thin (150 um) sheets of NC polymer that have pores of highly controlled size. (cdc.gov)
By controlling the conditions of solvent evaporation, controlled pores are formed in the resulting polymer sheet (membrane). (cdc.gov)
A membrane is a filter with small pores that let some of the substances through and others not. (tue.nl)
He suspects that's because the pores are not only essential for molecular transport, but they are also structural components of the double lipid layer that is the nuclear membrane. (news-medical.net)
Even if most of the 100s to 1000s of pores on any given cell nucleus are in decent shape and functioning, damage to a few can turn the nuclear membrane into a permeable barrier, allowing leakage of the wrong molecules in or out of the nucleus. (news-medical.net)

The liposome loading within the selective polyamide (PA) layer of the TFN membrane can be precisely controlled by manipulating spraying conditions to eliminate the wastage of precious additives compared to the conventional blending method. (ntu.edu.sg)
Proteoliposome-Incorporated Seawater Reverse Osmosis Polyamide Membrane: Is the Aquaporin Water Channel Effect in Improving Membrane Performance Overestimated? (bvsalud.org)
The water channel feature of the aquaporin (AQP) is considered to be the key in improving the permselectivity of AQP-based thin- film composite (TFC) polyamide (PA) membranes , yet much less attention has been paid to the physicochemical property changes of the PA layer induced by AQP-reconstituted proteoliposomes. (bvsalud.org)

3.1 This test method tests the hydrostatic resistance of a waterproofing membrane and can be used to compare the hydrostatic resistance of waterproofing membranes. (astm.org)
1.1 This test method measures the hydrostatic resistance of a waterproofing membrane under controlled laboratory conditions. (astm.org)
And if the floor will get wet for prolonged periods, it's a good idea to install a waterproofing membrane. (hometips.com)
Features Polyethylene membrane roll designed for waterproofing and vapor control Made with polypropylene fabric on both sides used for waterproofi. (thetoollocker.com)
Features Pliable sheet-applied waterproofing membrane and vapor-retarder Ready-to-tile sheet membrane 8-mil-thick and guarantees uniform thickness. (thetoollocker.com)
Waterproofing membranes are produced according to weather conditions. (gbgtr.com)
GBG supports its customers for choosing the appropriate Waterproofing membranes for their project through its proffessional technical team and serves for all importing & exporting procedures. (gbgtr.com)

We also supply ground gas protection membranes protecting structures from harmful ground gases such as radon, carbon dioxide, methane & hydrocarbons. (deltamembranes.com)
The eardrum, or tympanic membrane, forms the interface between the outside world and the delicate bony structures of the middle ear - the ossicles - that conduct sound vibrations to the inner ear. (nature.com)
Understanding the myriad biochemical roles of membranes requires the ability to prepare synthetic versions of these complex multi-layered structures, which has been a long-standing challenge. (scripps.edu)

botiss Jason® membrane is a native collagen membrane obtained from porcine pericardium, developed and manufactured for dental tissue regeneration. (straumann.com)
botiss collprotect® membrane is a native collagen membrane made of porcine dermis. (straumann.com)
The study aimed to verify histologically the bone repair following the use of resorbable collagen membrane with or without ethyl cyanoacrylate fixation. (bvsalud.org)

Protein molecules that span the lipid bilayer mediate nearly all of the other functions of the membrane, transporting specific molecules across it, for example, or catalyzing membrane-associated reactions, such as ATP synthesis. (nih.gov)

Each membrane protein clone in the MPA includes a C-terminal epitope tag, allowing confirmation of protein expression and the ability to verify the integrity of the membrane protein library. (genengnews.com)
Because the MPA expresses each membrane protein directly within living cells, it can be used to identify the targets of many types of interactions that require functional readouts based on cellular activity. (genengnews.com)
Integral Molecular's MPA is a high-throughput cell-based platform for identifying the membrane protein targets of antibodies and other ligands. (genengnews.com)
The MPA was initially validated by testing the specificity of antibodies with known membrane protein targets. (genengnews.com)
For the anti-P2X3 candidate, the MPA also identified binding to an additional membrane protein, informing the final lead selection in this program to avoid off-target binding that could cause patient side-effects. (genengnews.com)
The bacterial protein shown here uses the energy from light (photons) to activate the pumping of protons across the plasma membrane. (nih.gov)
these protein sensors, or receptors, transfer information-rather than ions or molecules-across the membrane. (nih.gov)
Despite their differing functions, all biological membranes have a common general structure: each is a very thin film of lipid and protein molecules, held together mainly by noncovalent interactions. (nih.gov)
In Chapters 12 and 13 we discuss the internal membranes of the cell and the protein traffic through and between them. (nih.gov)
In addition, sphingolipid-dependent signals control phosphorylation of protein kinase C (Pkc1), which plays an essential role in the pathways that link the cell cycle and ribosome biogenesis to membrane growth. (escholarship.org)

Membrane filters are abundantly used in wastewater treatment to remove and filter out pollutants. (maximizemarketresearch.com)
Rapidly increasing wastewater treatment activity in the entire world is also a reason for the increasing demand for membrane filters in the market. (maximizemarketresearch.com)

Inside eucaryotic cells, the membranes of the endoplasmic reticulum, Golgi apparatus, mitochondria, and other membrane-enclosed organelles maintain the characteristic differences between the contents of each organelle and the cytosol. (nih.gov)
Biochemical dissection of AP-1 recruitment onto Golgi membranes. (rupress.org)
Recruitment of the Golgi-specific AP-1 adaptor complex onto Golgi membranes is thought to be a prerequisite for clathrin coat assembly on the TGN. (rupress.org)
We have used an in vitro assay to examine the translocation of cytosolic AP-1 onto purified Golgi membranes. (rupress.org)
Association of AP-1 with the membranes required GTP or GTP analogues and was inhibited by the fungal metabolite, brefeldin A. In the presence of GTP gamma S, binding of AP-1 to Golgi membranes was strictly dependent on the concentration of cytosol added to the assay. (rupress.org)
Using only an adaptor-enriched fraction from cytosol, purified myristoylated ARF1, and Golgi membranes, the GTP gamma S-dependent recruitment of AP-1 could be reconstituted. (rupress.org)
Our results show that the association of the AP-1 complex with Golgi membranes, like the coatomer complex, requires ARF, which accounts for the sensitivity of both to brefeldin A. In addition, they provide the basis for a model for the early biochemical events that lead to clathrin-coated vesicle formation on the TGN. (rupress.org)

However, if the floor tends to flex, consider installing an isolation membrane. (hometips.com)

40 nm, performance which is superior to commercial alumina membranes. (nature.com)

In this work, we demonstrated the effectiveness of using spray-assisted interfacial polymerization (IP) technique in fabricating liposome-integrated thin film nanocomposite (TFN) membranes for seawater reverse osmosis (SWRO). (ntu.edu.sg)

The processes are liable to membrane contaminate the effect that decreases in penetrate flux. (maximizemarketresearch.com)
In addition, novel membrane processes and applications of hollow fiber membranes are introduced. (elsevier.com)
People interested in membrane technologies and membrane processes, especially hollow fiber membranes. (elsevier.com)
Based on our long-standing experience in multi-layer coating and high-quality manufacturing processes, FUJIFILM is developing and producing unique membranes to filter microscopic particles out of gas or liquids. (fujifilm.com)

These membrane filters work by allowing CO 2 to pass through the membrane more quickly than the other constituents in the mixed gas. (eurekalert.org)
This study systematically investigated the roles of proteoliposome constituents ( liposome / detergent /AQP) in affecting the physicochemical properties and performance of the membranes . (bvsalud.org)

SINTEF high pressure membrane test rig equipped with mini-compressor (membrane area: ca. 10 - 30 cm2, gas flow rate: 0.5 - 1.5 Nm3/hr, pressure: 1 - 90bar, temperature: 25 - 90 oC, CO 2 content in gas: 5 - 90 vol. (sintef.no)

What are the signs and symptoms of Pediatric Tympanic Membrane Perforation (Ruptured Eardrum)? (childrens.com)
Accidents, injuries and infections can cause tympanic membrane perforation. (childrens.com)

Features Available in 1 gallon, 3-1/2 gallon or 5 gallon buckets Ready-to-use liquid membrane can be applied with a brush or roller Extremely quic. (thetoollocker.com)
Removal of phenol from aqueous solution by a new emulsion liquid membrane (ELM) system and its heat-induced demulsification have been investigated. (semanticscholar.org)
The present study deals with the removal of phenol from aqueous solution using the emulsion liquid membrane technique. (semanticscholar.org)
Box-Behnken design was utilized to obtain optimized process condition for maximizing lactic acid extraction efficiency and initial extraction rate by emulsion liquid membrane (ELM) process. (semanticscholar.org)
The purpose of this study is to explore the emulsion liquid membrane stability for acetaminophen (ACTP) removal from aqueous solution by manipulating the concentration of stripping agent, agitation speed, extraction time, and treat ratio. (semanticscholar.org)
This work aims to the extraction of the priority pollutant 4-nitrophenol (4-NP) from water by emulsion liquid membrane (ELM). (semanticscholar.org)
Study on a new surfactant for removal of phenol from wastewater by emulsion liquid membrane. (semanticscholar.org)

Serratia marcescens is an opportunistic pathogen that can utilize chitin as a carbon source, through its ability to produce chitin-degrading enzymes to digest chitin and membrane transporters to transport the degradation products (chitooligosaccharides) into the cells. (jbc.org)
Our membranes exhibit outstanding handling properties, controlled degradation patterns and are characterized by their excellent biocompatibility, making them the ideal choice for applications in implant dentistry and periodontology. (straumann.com)

Phospholipids are asymmetrically distributed between the lipid bilayer of plasma membranes in which phosphatidylserine (PtdSer) is confined to the inner leaflet. (jbc.org)
This lipid bilayer provides the basic fluid structure of the membrane and serves as a relatively impermeable barrier to the passage of most water-soluble molecules. (nih.gov)
The liposomal membrane , providing a platform for the system, was prepared by the self -assembly of an oligonucleotide lipid , a phospholipid and a cationic synthetic lipid . (bvsalud.org)

TRPM3 activity depends on the membrane phospholipid phosphatidylinositol 4,5-bisphosphate (PI(4,5)P 2 ), but the molecular mechanism of activation by PI(4,5)P 2 is not known. (jbc.org)
To address the need for antibody target deconvolution and receptor identification, Integral Molecular has developed the Membrane Proteome Array (MPA). (genengnews.com)
Layer-by-layer membrane assembly allows us to create synthetic cells with membranes of arbitrary complexity at the molecular and supramolecular scale," said TSRI Assistant Professor Brian Paegel, who authored the study with Research Associate Sandro Matosevic. (scripps.edu)
We can now control the molecular composition of the inner and outer layers of a bilayer membrane, and even assemble multi-layered membranes that resemble the envelope of the cell nucleus. (scripps.edu)
We can now control the molecular composition of the inner and outer layers of a bilayer membrane," says Assistant Professor Brian Paegel. (scripps.edu)

Because when you understand what a phospholipid is, it starts to make sense why it would form a bilayer like this, and why it's the basis for so many membranes in biological systems. (khanacademy.org)

The tectorial membrane is above the hair cells within the ear. (innerbody.com)
The membrane is joined to the bony shelf of the cochlea and passes like a roof over the receptor cells, making contact with the tips of their hairs. (innerbody.com)
Here, we map the electrical potentials along the membrane of differentiated N1E-115 neuroblastoma cells with a potential-sensitive dye. (nih.gov)
The membranes surrounding and inside cells are involved in every aspect of biological function. (scripps.edu)
Although we focus mainly on the plasma membrane, most of the concepts discussed are applicable to the various internal membranes in cells as well. (nih.gov)
Recently, anion exchange membrane fuel cells (AEMFCs) have received attention as an attractive alternative to the acidic proton exchange membrane fuel cells (PEMFCs) that dominate in vehicle applications. (chalmers.se)

Gas separation membranes for power plant and chemical engineering applications are investigated with respect to their structural, chemical and transport properties. (fz-juelich.de)
Membrane technology is environmentally friendly and one of the most promising future separation technologies, especially for CO 2 capture since no chemicals involved, no secondary pollutants are emitted from the capture plant. (sintef.no)

Fine, superficial, radiating folds extend outward from the margins of the contracted membrane. (medscape.com)

The possibility to reach power densities almost equal those achieved in PEMFCs with membranes of similar thickness and while using non-PGM catalyzed cathodes has already been demonstrated. (chalmers.se)
The type and degree of symptoms experienced by an individual with epiretinal membrane (ERM) depends largely on the thickness of the membrane, the degree of retinal distortion it causes, the location of the wrinkling, and the presence or the absence of retinal detachment or edema. (medscape.com)

This work presents a readily scalable spray-assisted IP technique to fabricate liposome-integrated SWRO membrane for seawater desalination. (ntu.edu.sg)

ATP11A and ATP11C, type IV P-Type ATPases in plasma membranes, flip PtdSer from the outer to the inner leaflet, but involvement of other P4-ATPases is unclear. (jbc.org)
We herein demonstrated that once PtdSer was exposed on the cell surface of ATP11A −/− ATP11C −/− mouse T cell line (W3), its internalization to the inner leaflet of plasma membranes was negligible at 15 °C. (jbc.org)
The plasma membrane encloses the cell, defines its boundaries, and maintains the essential differences between the cytosol and the extracellular environment. (nih.gov)
A) An electron micrograph of a plasma membrane (of a human red blood cell) seen in cross section. (nih.gov)
A conserved signaling network monitors delivery of sphingolipids to the plasma membrane in budding yeast. (escholarship.org)
In budding yeast, cell cycle progression and ribosome biogenesis are dependent on plasma membrane growth, which ensures that events of cell growth are coordinated with each other and with the cell cycle. (escholarship.org)
A conserved signaling network appears to play an essential role in signaling by responding to delivery of sphingolipids to the plasma membrane. (escholarship.org)

Anatomy54

Organisms12

Diseases2

Chemicals and Drugs99

Analytical, Diagnostic and Therapeutic Techniques and Equipment29

Phenomena and Processes57

Disciplines and Occupations4

Technology, Industry, Agriculture7

Information Science3

Health Care1

Extra-vesicular binding of noradrenaline and guanethidine in the adrenergic neurones of the rat heart: a proposed site of action of adrenergic neurone blocking agents. (1/2566)

The Saccharomyces cerevisiae CWH8 gene is required for full levels of dolichol-linked oligosaccharides in the endoplasmic reticulum and for efficient N-glycosylation. (2/2566)

Isolation and characterization of major intrinsic microsomal membrane proteins. (3/2566)

Kinetic analysis of drug-receptor interactions of long-acting beta2 sympathomimetics in isolated receptor membranes: evidence against prolonged effects of salmeterol and formoterol on receptor-coupled adenylyl cyclase. (4/2566)

Biochemical and electrophysiological studies on the mechanism of action of PNU-151774E, a novel antiepileptic compound. (5/2566)

Localization and environment of tryptophans in soluble and membrane-bound states of a pore-forming toxin from Staphylococcus aureus. (6/2566)

Cellular mechanisms contributing to response variability of cortical neurons in vivo. (7/2566)

Direct evidence of Na+/Ca2+ exchange in squid rhabdomeric membranes. (8/2566)

Membranes

Membrane Lipids

Cell Membrane

Intracellular Membranes

Membrane Potentials

Membranes, Artificial

Erythrocyte Membrane

Membrane Fluidity

Cell Membrane Permeability

Basement Membrane

Membrane Transport Proteins

Membrane Glycoproteins

Lipid Bilayers

Mitochondrial Membranes

Microscopy, Electron

Protein Transport

Synaptic Membranes

Cell Line

Liposomes

Protein Binding

Calcium

Models, Biological

Cell Fractionation

Protein Structure, Tertiary

Carrier Proteins

Extraembryonic Membranes

Hydrogen-Ion Concentration

Detergents

Escherichia coli

Electrophoresis, Polyacrylamide Gel

Endoplasmic Reticulum

Phosphatidylcholines

Cells, Cultured

Golgi Apparatus

Mutation

Bacterial Proteins

Microscopy, Fluorescence

Freeze Fracturing

Molecular Sequence Data

Molecular Weight

Recombinant Fusion Proteins

Cell Membrane Structures

Potassium

Microvilli

Temperature

Subcellular Fractions

Mitochondria

Amino Acid Sequence

Biological Transport, Active

Endocytosis

Microscopy, Confocal

Cytoplasm

Erythrocytes

Models, Molecular

Binding Sites

Rabbits

Membrane Potential, Mitochondrial

Purple Membrane

Ion Channels

Time Factors

Sodium

Protein Conformation

Solubility

Cattle

Base Sequence

Fluorescent Antibody Technique

Fluorescent Dyes

Adenosine Triphosphate

Electric Conductivity

Nictitating Membrane

Bruch Membrane

Permeability

Signal Transduction

Protein Structure, Secondary

Octoxynol

Microscopy, Immunoelectron

Cytosol

Exocytosis

Cricetinae

Cholesterol