Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A chromatographic technique that utilizes the ability of biological molecules to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.
Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.
Techniques used to separate mixtures of substances based on differences in the relative affinities of the substances for mobile and stationary phases. A mobile phase (fluid or gas) passes through a column containing a stationary phase of porous solid or liquid coated on a solid support. Usage is both analytical for small amounts and preparative for bulk amounts.
Chromatographic techniques in which the mobile phase is a liquid.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
The sum of the weight of all the atoms in a molecule.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Any compound containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety such as an acylglycerol (see GLYCERIDES), a sphingoid, a ceramide (CERAMIDES) (N-acylsphingoid) or a prenyl phosphate. (From IUPAC's webpage)
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
A subclass of ACIDIC GLYCOSPHINGOLIPIDS. They contain one or more sialic acid (N-ACETYLNEURAMINIC ACID) residues. Using the Svennerholm system of abbrevations, gangliosides are designated G for ganglioside, plus subscript M, D, or T for mono-, di-, or trisialo, respectively, the subscript letter being followed by a subscript arabic numeral to indicated sequence of migration in thin-layer chromatograms. (From Oxford Dictionary of Biochemistry and Molecular Biology, 1997)
The rate dynamics in chemical or physical systems.
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.
A type of ion exchange chromatography using diethylaminoethyl cellulose (DEAE-CELLULOSE) as a positively charged resin. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A non-crystalline form of silicon oxide that has absorptive properties. It is commonly used as a desiccating agent and as a stationary phase for CHROMATOGRAPHY. The fully hydrated form of silica gel has distinct properties and is referred to as SILICIC ACID.
The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.
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.
An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A method of gel filtration chromatography using agarose, the non-ionic component of agar, for the separation of compounds with molecular weights up to several million.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
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)
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
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.
Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.
Lipids containing at least one monosaccharide residue and either a sphingoid or a ceramide (CERAMIDES). They are subdivided into NEUTRAL GLYCOSPHINGOLIPIDS comprising monoglycosyl- and oligoglycosylsphingoids and monoglycosyl- and oligoglycosylceramides; and ACIDIC GLYCOSPHINGOLIPIDS which comprises sialosylglycosylsphingolipids (GANGLIOSIDES); SULFOGLYCOSPHINGOLIPIDS (formerly known as sulfatides), glycuronoglycosphingolipids, and phospho- and phosphonoglycosphingolipids. (From IUPAC's webpage)
The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
The largest class of organic compounds, including STARCH; GLYCOGEN; CELLULOSE; POLYSACCHARIDES; and simple MONOSACCHARIDES. Carbohydrates are composed of carbon, hydrogen, and oxygen in a ratio of Cn(H2O)n.
A series of steps taken in order to conduct research.
A form of SILICON DIOXIDE composed of skeletons of prehistoric aquatic plants which is used for its ABSORPTION quality, taking up 1.5-4 times its weight in water. The microscopic sharp edges are useful for insect control but can also be an inhalation hazard. It has been used in baked goods and animal feed. Kieselguhr is German for flint + earthy sediment.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A chromatography technique in which the stationary phase is composed of a non-polar substance with a polar mobile phase, in contrast to normal-phase chromatography in which the stationary phase is a polar substance with a non-polar mobile phase.
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Substances that display the physical properties of ELASTICITY and VISCOSITY. The dual-nature of these substances causes them to resist applied forces in a time-dependent manner.
The characteristic 3-dimensional shape of a carbohydrate.
Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Unstable isotopes of phosphorus that decay or disintegrate emitting radiation. P atoms with atomic weights 28-34 except 31 are radioactive phosphorus isotopes.
The chemical and physical integrity of a pharmaceutical product.
The process of cleaving a chemical compound by the addition of a molecule of water.
Characteristics or attributes of the outer boundaries of objects, including molecules.
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)
Electrophoresis in which a pH gradient is established in a gel medium and proteins migrate until they reach the site (or focus) at which the pH is equal to their isoelectric point.
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
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)
The measurement of the density of a material by measuring the amount of light or radiation passing through (or absorbed by) the material.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
A mass spectrometric technique that is used for the analysis of a wide range of biomolecules, such as glycoalkaloids, glycoproteins, polysaccharides, and peptides. Positive and negative fast atom bombardment spectra are recorded on a mass spectrometer fitted with an atom gun with xenon as the customary beam. The mass spectra obtained contain molecular weight recognition as well as sequence information.
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.
Elements of limited time intervals, contributing to particular results or situations.
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.
A colorless, flammable liquid used in the manufacture of FORMALDEHYDE and ACETIC ACID, in chemical synthesis, antifreeze, and as a solvent. Ingestion of methanol is toxic and may cause blindness.
A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.
Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.
GLYCOSPHINGOLIPIDS with a sulfate group esterified to one of the sugar groups.
Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.
Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
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
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
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.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Method for assessing flow through a system by injection of a known quantity of radionuclide into the system and monitoring its concentration over time at a specific point in the system. (From Dorland, 28th ed)
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
GLYCEROPHOSPHOLIPIDS in which one of the two acyl chains is attached to glycerol with an ether alkenyl linkage instead of an ester as with the other glycerophospholipids.
Measurement and evaluation of the components of substances to be taken as FOOD.
A ganglioside present in abnormally large amounts in the brain and liver due to a deficient biosynthetic enzyme, G(M3):UDP-N-acetylgalactosaminyltransferase. Deficiency of this enzyme prevents the formation of G(M2) ganglioside from G(M3) ganglioside and is the cause of an anabolic sphingolipidosis.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Usually high-molecular-weight, straight-chain primary alcohols, but can also range from as few as 4 carbons, derived from natural fats and oils, including lauryl, stearyl, oleyl, and linoleyl alcohols. They are used in pharmaceuticals, cosmetics, detergents, plastics, and lube oils and in textile manufacture. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Established cell cultures that have the potential to propagate indefinitely.
The outer layer of the woody parts of plants.
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 mass spectrometry technique using two (MS/MS) or more mass analyzers. With two in tandem, the precursor ions are mass-selected by a first mass analyzer, and focused into a collision region where they are then fragmented into product ions which are then characterized by a second mass analyzer. A variety of techniques are used to separate the compounds, ionize them, and introduce them to the first mass analyzer. For example, for in GC-MS/MS, GAS CHROMATOGRAPHY-MASS SPECTROMETRY is involved in separating relatively small compounds by GAS CHROMATOGRAPHY prior to injecting them into an ionization chamber for the mass selection.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
Proteins prepared by recombinant DNA technology.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
A group of naturally occurring N-and O-acyl derivatives of the deoxyamino sugar neuraminic acid. They are ubiquitously distributed in many tissues.
A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
A group of GLYCOLIPIDS in which the sugar group is GALACTOSE. They are distinguished from GLYCOSPHINGOLIPIDS in lacking nitrogen. They constitute the majority of MEMBRANE LIPIDS in PLANTS.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.
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.
Solid dosage forms, of varying weight, size, and shape, which may be molded or compressed, and which contain a medicinal substance in pure or diluted form. (Dorland, 28th ed)
Plants whose roots, leaves, seeds, bark, or other constituent parts possess therapeutic, tonic, purgative, curative or other pharmacologic attributes, when administered to man or animals.
A hexose or fermentable monosaccharide and isomer of glucose from manna, the ash Fraxinus ornus and related plants. (From Grant & Hackh's Chemical Dictionary, 5th ed & Random House Unabridged Dictionary, 2d ed)
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
Antibodies produced by a single clone of cells.
Separation of a mixture in successive stages, each stage removing from the mixture some proportion of one of the substances, for example by differential solubility in water-solvent mixtures. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
GLYCEROL esterified with FATTY ACIDS.
Enzymes that catalyze the hydrolysis of ester bonds within RNA. EC 3.1.-.
A method of separation of two or more substances by repeated distribution between two immiscible liquid phases that move past each other in opposite directions. It is a form of liquid-liquid chromatography. (Stedman, 25th ed)
The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)
A hybrid separation technique combining both chromatographic and electrophoretic separation principles. While the method was invented to separate neutral species, it can also be applied to charged molecules such as small peptides.
Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.
The three primary germinal layers (ECTODERM; ENDODERM; and MESODERM) developed during GASTRULATION that provide tissues and body plan of a mature organism. They derive from two early layers, hypoblast and epiblast.
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.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
Derivatives of PHOSPHATIDYLCHOLINES obtained by their partial hydrolysis which removes one of the fatty acid moieties.
Relating to the size of solids.
Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.
The pH in solutions of proteins and related compounds at which the dipolar ions are at a maximum.
The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
A specific monosialoganglioside that accumulates abnormally within the nervous system due to a deficiency of GM1-b-galactosidase, resulting in GM1 gangliosidosis.
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 group of enzymes with the general formula CMP-N-acetylneuraminate:acceptor N-acetylneuraminyl transferase. They catalyze the transfer of N-acetylneuraminic acid from CMP-N-acetylneuraminic acid to an acceptor, which is usually the terminal sugar residue of an oligosaccharide, a glycoprotein, or a glycolipid. EC 2.4.99.-.
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)
A group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase pathway. They are extremely potent mediators of a diverse group of physiological processes.
Adherent debris produced when cutting the enamel or dentin in cavity preparation. It is about 1 micron thick and its composition reflects the underlying dentin, although different quantities and qualities of smear layer can be produced by the various instrumentation techniques. Its function is presumed to be protective, as it lowers dentin permeability. However, it masks the underlying dentin and interferes with attempts to bond dental material to the dentin.
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.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
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.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
Members of the class of neutral glycosphingolipids. They are the basic units of SPHINGOLIPIDS. They are sphingoids attached via their amino groups to a long chain fatty acyl group. They abnormally accumulate in FABRY DISEASE.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
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.
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
A class of enzymes that catalyze the hydrolysis of one of the two ester bonds in a phosphodiester compound. EC 3.1.4.
Nucleotides in which the purine or pyrimidine base is combined with ribose. (Dorland, 28th ed)
Technique involving the diffusion of antigen or antibody through a semisolid medium, usually agar or agarose gel, with the result being a precipitin reaction.
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.
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)
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.
A common saturated fatty acid found in fats and waxes including olive oil, palm oil, and body lipids.
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.
A group of compounds with the general formula M10(PO4)6(OH)2, where M is barium, strontium, or calcium. The compounds are the principal mineral in phosphorite deposits, biological tissue, human bones, and teeth. They are also used as an anticaking agent and polymer catalysts. (Grant & Hackh's Chemical Dictionary, 5th ed)
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.
The development and use of techniques and equipment to study or perform chemical reactions, with small quantities of materials, frequently less than a milligram or a milliliter.
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.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
An unsaturated, essential fatty acid. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is formed by the synthesis from dietary linoleic acid and is a precursor in the biosynthesis of prostaglandins, thromboxanes, and leukotrienes.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.
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.
Methods of creating machines and devices.
Unstable isotopes of iodine that decay or disintegrate emitting radiation. I atoms with atomic weights 117-139, except I 127, are radioactive iodine isotopes.
Proteins found in any species of bacterium.
Proteins that share the common characteristic of binding to carbohydrates. Some ANTIBODIES and carbohydrate-metabolizing proteins (ENZYMES) also bind to carbohydrates, however they are not considered lectins. PLANT LECTINS are carbohydrate-binding proteins that have been primarily identified by their hemagglutinating activity (HEMAGGLUTININS). However, a variety of lectins occur in animal species where they serve diverse array of functions through specific carbohydrate recognition.
Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.
Sites on an antigen that interact with specific antibodies.
The relationship between the dose of an administered drug and the response of the organism to the drug.
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Compounds in which a methyl group is attached to the cyano moiety.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.
Presence of warmth or heat or a temperature notably higher than an accustomed norm.
The formation of a solid in a solution as a result of a chemical reaction or the aggregation of soluble substances into complexes large enough to fall out of solution.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Changes in the amounts of various chemicals (neurotransmitters, receptors, enzymes, and other metabolites) specific to the area of the central nervous system contained within the head. These are monitored over time, during sensory stimulation, or under different disease states.
Methodologies used for the isolation, identification, detection, and quantitation of chemical substances.
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
Transport proteins that carry specific substances in the blood or across cell membranes.
Sulfuric acid diammonium salt. It is used in CHEMICAL FRACTIONATION of proteins.
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)
Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.
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.
Concentration or quantity that is derived from the smallest measure that can be detected with reasonable certainty for a given analytical procedure.
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.
Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.
Substances that reduce the growth or reproduction of BACTERIA.
Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.
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.
An extraction method that separates analytes using a solid phase and a liquid phase. It is used for preparative sample cleanup before analysis by CHROMATOGRAPHY and other analytical methods.
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.
High-molecular-weight insoluble polymers that contain functional cationic groups capable of undergoing exchange reactions with anions.
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 mineral component of bones and teeth; it has been used therapeutically as a prosthetic aid and in the prevention and treatment of osteoporosis.
Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.
An electrochemical process in which macromolecules or colloidal particles with a net electric charge migrate in a solution under the influence of an electric current.
The phenomenon whereby certain chemical compounds have structures that are different although the compounds possess the same elemental composition. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.
The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.
Centrifugation with a centrifuge that develops centrifugal fields of more than 100,000 times gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Pyrolysis of organic compounds at the temperature of a hydrogen-air flame to produce ionic intermediates which can be collected and the resulting ion current measured by gas chromatography.
The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.
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.
Projection neurons in the CEREBRAL CORTEX and the HIPPOCAMPUS. Pyramidal cells have a pyramid-shaped soma with the apex and an apical dendrite pointed toward the pial surface and other dendrites and an axon emerging from the base. The axons may have local collaterals but also project outside their cortical region.
The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.

Prodigious substrate specificity of AAC(6')-APH(2"), an aminoglycoside antibiotic resistance determinant in enterococci and staphylococci. (1/5786)

BACKGROUND: High-level gentamicin resistance in enterococci and staphylococci is conferred by AAC(6')-APH(2"), an enzyme with 6'-N-acetyltransferase and 2"-O-phosphotransferase activities. The presence of this enzyme in pathogenic gram-positive bacteria prevents the successful use of gentamicin C and most other aminoglycosides as therapeutic agents. RESULTS: In an effort to understand the mechanism of aminoglycoside modification, we expressed AAC(6')-APH(2") in Bacillus subtilis. The purified enzyme is monomeric with a molecular mass of 57 kDa and displays both the expected aminoglycoside N-acetyltransferase and O-phosphotransferase activities. Structure-function analysis with various aminoglycosides substrates reveals an enzyme with broad specificity in both enzymatic activities, accounting for AAC(6')-APH(2")'s dramatic negative impact on clinical aminoglycoside therapy. Both lividomycin A and paromomycin, aminoglycosides lacking a 6'-amino group, were acetylated by AAC(6')-APH(2"). The infrared spectrum of the product of paromomycin acetylation yielded a signal consistent with O-acetylation. Mass spectral and nuclear magnetic resonance analysis of the products of neomycin phosphorylation indicated that phosphoryl transfer occurred primarily at the 3'-OH of the 6-aminohexose ring A, and that some diphosphorylated material was also present with phosphates at the 3'-OH and the 3"'-OH of ring D, both unprecedented observations for this enzyme. Furthermore, the phosphorylation site of lividomycin A was determined to be the 5"-OH of the pentose ring C. CONCLUSIONS: The bifunctional AAC(6')-APH(2") has the capacity to inactivate virtually all clinically important aminoglycosides through N- and O-acetylation and phosphorylation of hydroxyl groups. The extremely broad substrate specificity of this enzyme will impact on future development of aminoglycosides and presents a significant challenge for antibiotic design.  (+info)

A new bile acid conjugate, ciliatocholic acid, from bovine gall bladder bile. (2/5786)

This study was carried out to investigate the occurrence of ciliatocholic acid in bovine gall bladder bile. Ciliatocholic acid was synthesized according to the method described by Bergstrom and Norman for the synthesis of taurocholic acid. Elemental analysis, melting point, and the infrared spectrum of this substance were determined. An isolation procedure for ciliatocholic acid was established by stepwise elution with an HCl-ethanol solvent system using a Dowex-1 anion exchange resin column chromatographic technique. Ciliatocholic acid amounting to 158 mug (as ciliatine) per 100 ml of gall bladder bile was found in the fraction eluted with 0.01 N HCl in 50% ethanol. This coumpound was purified by preparative thin-layer chromatography and confirmed to be ciliatocholic acid from the hydrolytic stability, phosphorus determination, and chromatographic behavior. Thus, bovine gall bladder bile contains a small amount of ciliatocholic acid.  (+info)

Lipolytic action of cholera toxin on fat cells. Re-examination of the concept implicating GM1 ganglioside as the native membrane receptor. (3/5786)

The possible role of galactosyl-N-acetylgalactosaminyl-[N-acetylneuraminyl]-galactosylglucosylceramide (GM1) ganglioside in the lipolytic activity of cholera toxin on isolated fat cells has been examined. Analyses of the ganglioside content and composition of intact fat cells, their membranous ghosts, and the total particulate fraction of these cells indicate that N-acetylneuraminylgalactosylglucosylceramide (GM3) represents the major ganglioside, with substantial amounts of N-acetylgalactosaminyl-[N-acetylneuraminyl]-galactosylglucosylceramide (GM2) and smaller amounts of other higher homologues also present. Native GM1 was not detected in any of these preparations. Examination of the relative capacities of various exogenously added radiolabeled sphingolipids to bind to the cells indicated that GM2 and glucosylsphingosine were accumulated by the cells to extents comparable to GM1. Galactosylsphingosine and sulfatide also exhibited significant, although lesser, binding affinities for the cells. The adipocytes appeared to nonspecifically bind exogenously added GM1; saturation of binding sites for GM1 could not be observed up to the highest concentration tested (2 X 10(-4) M), wherein about 7 X 10(9) molecules were associated with the cells. Essentially all of this exogenously added GM1 was found bound to the plasma membrane "ghost" fraction. Investigation of the biological responses of the cells confirmed their sensitivities to both cholera toxin and epinephrine-stimulated lipolysis, as well as the lag period displayed during the toxin's action. While we could confirm that the toxin's lipolytic activity can be enhanced by prior treatment of the fat cells with GM1, several of the observed characteristics of this phenomenon differ from earlier reported findings. Accordingly, added GM1 was able to enhance only the subsequent rate, but not the extent, of toxin-stimulated glycerol release (lipolysis) from the cells. We also were unable to confirm the ability of GM1 to enhance the toxin's activity at either saturating or at low toxin concentrations. The limited ability of added GM1 to enhance the toxin's activity appeared in a unique bell-shaped dose-response manner. The inability of high levels of GM1 to stimulate a dose of toxin that was ineffective on native cells suggests that the earlier reported ability of crude brain gangliosides to accomplish this was due to some component other than GM1 in the crude extract. While several glycosphingolipids and some other carbohydrate-containing substances that were tested lacked the ability to mimic the enhancing effect of GM1, 4-methylumbelliferyl-beta-D-galactoside exhibited an effect similar to, although less pronounced than, that of GM1. The findings in these studies are unable to lend support to the earlier hypothesis that (a) GM1 is cholera toxin's naturally occurring membrane receptor on native fat cells, and (b) the ability of exogenously added GM1 to enhance the toxin's lipolytic activity represents the specific creation of additional natural receptors on adipocytes...  (+info)

Elevated expression of the CD4 receptor and cell cycle arrest are induced in Jurkat cells by treatment with the novel cyclic dinucleotide 3',5'-cyclic diguanylic acid. (4/5786)

The effect of the novel, naturally occurring nucleotide cyclic diguanylic acid (c-di-GMP) on the lymphoblastoid CD4+ Jurkat cell line was studied. When exposed to 50 microM c-di-GMP, Jurkat cells exhibited a markedly elevated expression of the CD4 receptor of up to 6.3-fold over controls. C-di-GMP also causes blockage of the cell cycle at the S-phase, characterized by increased cellular thymidine uptake, reduction in G2/M-phase cells, increase in S-phase cells and decreased cell division. Additionally c-di-GMP naturally enters these cells and binds irreversibly to the P21ras protein. The effects described appear to be unique for c-di-GMP.  (+info)

Esterases in serum-containing growth media counteract chloramphenicol acetyltransferase activity in vitro. (5/5786)

The spirochete Borrelia burgdorferi was unexpectedly found to be as susceptible to diacetyl chloramphenicol, the product of the enzyme chloramphenicol acetyltransferase, as it was to chloramphenicol itself. The susceptibilities of Escherichia coli and Bacillus subtilis, as well as that of B. burgdorferi, to diacetyl chloramphenicol were then assayed in different media. All three species were susceptible to diacetyl chloramphenicol when growth media were supplemented with rabbit serum or, to a lesser extent, human serum. Susceptibility of E. coli and B. subtilis to diacetyl chloramphenicol was not observed in the absence of serum, when horse serum was used, or when the rabbit or human serum was heated first. In the presence of 10% rabbit serum, a strain of E. coli bearing the chloramphenicol acetyltransferase (cat) gene had a fourfold-lower resistance to chloramphenicol than in the absence of serum. A plate bioassay for chloramphenicol activity showed the conversion by rabbit, mouse, and human sera but not bacterial cell extracts or heated serum of diacetyl chloramphenicol to an inhibitory compound. Deacetylation of acetyl chloramphenicol by serum components was demonstrated by using fluorescent substrates and thin-layer chromatography. These studies indicate that esterases of serum can convert diacetyl chloramphenicol back to an active antibiotic, and thus, in vitro findings may not accurately reflect the level of chloramphenicol resistance by cat-bearing bacteria in vivo.  (+info)

An improved separation procedure for nucleoside monophosphates on polyethyleneimine-(PEI-)cellulose thin layers. (6/5786)

A procedure is described for the two-dimensional separation of the 4 major and 16 modified nucleoside-(5') monophosphates on anion-exchange thin layers of polyethyleneimine- (PEI-)cellulose. The method, which is simple and less time-consuming than existing partition chromatographic methods, may be used for the identification of 5'-termini of RNA and RNA fragments.  (+info)

Accumulation of N-acyl-ethanolamine phospholipids in rat brains during post-decapitative ischemia: a 31p NMR study. (7/5786)

Phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy has been used to study accumulation of N-acyl-ethanolamine phospholipids in rat brains during post-decapitative ischemia. Lipids were extracted from rat brain homogenates and the extracts were thoroughly washed with aq. potassium ethylenediaminetetraacetic acid (EDTA). The lower organic phases were isolated and evaporated to dryness under a stream of nitrogen and the lipids were redissolved in CDCl3-CH3OH-H2O 100.0:29.9:5.2 (v/v/v) for NMR analysis. Increasing the period of post-decapitative ischemia resulted in an accumulation of two signals in the NMR spectra at 0.18 and 0.22 ppm (relative to the chemical shift of 1,2-diacyl-sn-glycero-3-phosphocholine (PCDIACYL) at -0.84 ppm). These signals were identified as originating from 1,2-diacyl-sn-glycero-3-phospho-(N-acyl)-ethanolamine (NAPEDIACYL) and 1-(1'-alkenyl)-2-acyl-sn -glycero-3-phospho-(N-acyl)-ethanolamine (NAPEPLAS), respectively, by spiking with authentic materials. Additionally, the identification was verified by thin-layer chromatography, which also showed the accumulation of N-acyl-ethanolamine phospholipids. The use of K-EDTA instead of the commonly used Cs-EDTA in the preparation of the NMR samples allowed the separation of the chemical shifts of N-acyl-ethanolamine phospholipids from those of the ethanolamine phospholipids. Moreover, the chemical shift of cardiolipin was moved from 0.15 ppm observed with Cs-EDTA to about 0.31 ppm with K-EDTA. The present study demonstrates that it is possible to detect and quantify post-decapitative accumulation of NAPE subclasses (NAPEDIACYL and NAPEPLAS) in rat brains by the use of 31P NMR spectroscopy.  (+info)

Lipophilicity determination of some potential photosystem II inhibitors on reversed-phase high-performance thin-layer chromatography. (8/5786)

The retention characteristics of 25 2-cyano-3-methylthio-3-substituted amine-acrylates are determined using reversed-phase thin-layer chromatography (RP-TLC) with methanol-water mixtures as eluents. The relationship between Rm values and partition coefficients (C log P) are established. The Rm values decrease linearly with increasing methanol concentration in the eluent. The Rm values extrapolated to zero organic modifier concentration (Rm0) in the eluent are highly related to C log P. The Rm0 value can be used to evaluate the lipophilicity of this kind of compound.  (+info)

The presence of a smear layer has been associated with delayed healing, increased risk of infection, and decreased strength of the newly formed tissue. Therefore, removing or reducing the smear layer is an important step in wound care to promote optimal healing outcomes.

The term "smear layer" was first introduced by Dr. Jeffrey M. Olsen and colleagues in 2007, and since then it has been widely adopted in the medical field as a key concept in wound care.

... (TLC) is a chromatography technique used to separate non-volatile mixtures. Thin-layer chromatography ... "Applications of Thin Layer Chromatography". 2018-09-18. Retrieved 2018-09-25. "Thin Layer Chromatography: A ... Thin-layer chromatography, 2nd edition, Wiley Joseph Sherma, Bernard Fried (1991): Handbook of Thin-Layer Chromatography (= ... showing the thickness value of commercial regular and preparative Thin Layer Chromatography plates Thin Layer Chromatography: ...
... is a variant of liquid chromatography that is employed for the separation of enantiomers. It ... Ibuprofen by Thin-Layer Chromatography. An Improved Analytical Procedure". Journal of Planar Chromatography-Modern TLC. 17 (2 ... Del Bubba, Massimo; Checchini, Leonardo; Lepri, Luciano (2012). "Thin-layer chromatography enantioseparations on chiral ... baclofen by ligand exchange thin layer chromatography". Journal of Chromatographic Science. 54: 842-846. doi:10.1093/chromsci/ ...
... (HPTLC) is an enhanced form of thin-layer chromatography (TLC). A number of ... high performance thin-layer chromatography, Amsterdam, Elsevier Reich A., Schibli A. (2006): High Performance Thin-Layer ... Journal of Planar Chromatography-modern TLC 23 (4), 282-285 [2] F. Geiss (1987): Fundamentals of thin layer chromatography ... Thin-Layer Chromatography: Reagents and Detection Methods, Volume 1b, VCH, Weinheim Hahn-Deinstorp, E. (2000): Applied Thin- ...
"Dihydromorphine , Thin Layer Chromatography , Chemistry". Dureja. Handbook Of Pain Management pp. 67 Antkiewicz-Michaluk L, ...
Thin layer chromatography (TLC) is a simple separation technique that can be coupled with DAPPI-MS to identify lipids. Some of ... F., Poole, Colin (2015-01-01). Instrumental thin-layer chromatography. Elsevier. ISBN 9780124172234. OCLC 897437460. Han, Yehua ... Layer with Photopatterned Virtual Channel for the Separation of Peptides Using Two-Dimensional Thin Layer Chromatography- ... "Thin-Layer Chromatography/Desorption Atmospheric Pressure Photoionization Orbitrap Mass Spectrometry of Lipids". Analytical ...
by thin-layer chromatography". Transactions of the British Mycological Society. 49 (1): 11-17. doi:10.1016/S0007-1536(66)80029- ... Cheilocystidia (found on the edges of the gills), which are similar in shape to the pleurocystidia, are thin-walled, hyaline, ...
Waksmundzka-Hajnos, Monika; Sherma, Joseph; Kowalska, Teresa (2008). Thin layer chromatography in phytochemistry. CRC Press. ...
Examples include the silica layer in thin-layer chromatography Detector - the instrument used for qualitative and quantitative ... or a layer of solid particles spread on a support such as a glass plate (thin-layer chromatography). Different compounds in the ... Handbook of Thin-Layer Chromatography. Marcel Dekker Inc. ISBN 978-0824748661. OCLC 437068122. Displacement Chromatography 101 ... Thin-layer chromatography (TLC) is a widely employed laboratory technique used to separate different biochemicals on the basis ...
ISBN 978-0-306-10984-3. Lukasz Komsta; Monika Waksmundzka-Hajnos; Joseph Sherma (20 December 2013). Thin Layer Chromatography ...
Komsta L, Waksmundzka-Hajnos M, Sherma J (20 December 2013). Thin Layer Chromatography in Drug Analysis. CRC Press. pp. 652-. ... Biomedical Chromatography. 26 (12): 1589-95. doi:10.1002/bmc.2736. PMID 22495777. Anderson PO, Knoben JE, Troutman WG (22 ...
2013-10-20). Thin Layer Chromatography in Drug Analysis. CRC Press. p. 302. ISBN 9781466507166. Retrieved 2020-06-11. Marshall ...
... : Thin-layer Chromatography. Reinhold Publishing Co., New York 1963. J. M. Bobbitt, A. E Schwarting, and R. J. ... In 1968, Bobbitt became lead instructor for an American Chemical Society course on thin-layer chromatography and taught ... Additional research interests included the synthesis of nitrogen heterocycles, thin-layer chromatography, electrolytic ... Bobbitt was the author of two books on chromatography and some 120 research articles. ...
Pellotine Lundström, Jan; Agurell, Stig (1967). "Thin-layer chromatography of the peyote alkaloids". Journal of Chromatography ...
It produces thin-layer chromatography plates and accessories. The firm was started as Custom Service Chemicals in 1961 by four ...
Striegel, Mary F. and Jo Hill (1996). Thin-Layer Chromatography for Binding Media Analysis (PDF). United States of America: J. ...
More advanced analytical techniques, such as thin layer chromatography, high performance liquid chromatography, and mass ... 4. Thin layer chromatography of lichen substances" (PDF). Acta Chemica Scandinavica. 21: 1162-1172. doi:10.3891/acta.chem.scand ... In cases where the results of a spot test on the thallus are uncertain, it is possible to squash a thin section of the tissue ...
The irregularly branched, fruticose thallus of the lichen measures up to 8 mm (0.3 in). Thin-layer chromatography shows that ...
Myhill, D.; Jackson, D.S. (1963). "Separation of proline and hydroxyproline using thin-layer chromatography". Analytical ...
No lichen products were detected using thin-layer chromatography. It is somewhat similar in appearance to Astrothelium ...
The separation is first optimised using thin-layer chromatography before performing column chromatography. A column is prepared ... A thin-layer chromatograph can show how a mixture of compounds will behave when purified by column chromatography. ... The eluent is optimized in small scale pretests, often using thin layer chromatography (TLC) with the same stationary phase. ... Fair, JD; Kormos, CM (2008). "Flash column chromatograms estimated from thin-layer chromatography data". J Chromatogr A. 1211 ( ...
No secondary chemicals were detected using thin-layer chromatography. Øvstedal, Dag O.; Gremmen, Niek J.M. (2010). "New lichen ...
No secondary chemicals were detected using thin-layer chromatography. Øvstedal, Dag O.; Gremmen, Niek J.M. (2010). "New lichen ... The lichen has a thin, green-grey crust-like thallus that grows in bark fissures. Its ascospores, which number eight per ascus ...
The compound was isolated and identified using thin layer chromatography. In order to validate his theory that cetyl ...
Several lichen products have been detected using thin-layer chromatography. These are parietin and gyrophoric acid as major ... a cortical layer with a palisade paraplectenchyma, and the lack of a thick palisade cortical layer on the underside of the ... thalline exciple (the ring-shaped layer of tissue surrounding the hymenium). Neobrownliella brownlieae has a crustose thallus ...
Preparative thin-layer chromatography was used to separate the diastereomers. Epothilone B is a 16-membered polyketide ...
Phosphomolybdic acid is a stain used in thin-layer chromatography. Molybdenum is an essential element in most organisms; a 2008 ... a thin layer of molybdenum prevents contact of the lubricated parts. It also has semiconducting properties with distinct ...
J. J. Kirkland (1965). "Porous Thin-Layer Modified Glass Bead Supports for Gas Liquid Chromatography". Analytical Chemistry. 37 ... Layer-by-layer (LbL) deposition is a thin film fabrication technique. The films are formed by depositing alternating layers of ... Atomic layer deposition J. J. Richardson; et al. (2015). "Technology-driven layer-by-layer assembly of nanofilms". Science. 348 ... Liu, Weijing (2016). "Layer-by-Layer Deposition with Polymers Containing Nitrilotriacetate, A Convenient Route to Fabricate ...
... these are lichen products that are detectable using thin-layer chromatography. Feuerstein, Shirley Cunha; Aptroot, André; da ...
It can also be referred to as Centrifugal Thin-Layer Chromatography. It is a common technique for isolating compounds and can ... Here the solvent travels from the center of the circular chromatography silica layered on a plate towards the periphery. The ... Radial chromatography is a form of chromatography, a preparatory technique for separating chemical mixtures. ... Continuous Annular chromatography uses a stationary phase which is filled into an annular gap. The eluent is continuously fed ...
... , or RU, is a concept in thin layer chromatography. It is designed for the quantitative measurement of ... Articles needing additional references from December 2011, All articles needing additional references, Chromatography). ...
No lichen products were detected in this species using thin-layer chromatography. Czarnota, Paweł; Guzow-Krzemińska, Beata ( ...
First, the contaminants have to diffuse across the water boundary layer. The thickness of this layer is dependent on water flow ... The sorbent is placed into a chromatography column so that the chemicals that samples can be recovered using an organic solvent ... The SPMD consist of a thin-walled, nonporous, polyethylene membrane tube that is filled with high molecular weight lipid. These ...
Several sampling and analytical methods including thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC ...
... which are lichen products that can be detected using thin-layer chromatography. Feuerstein, Shirley Cunha; Lücking, Robert; ...
When ice forms on the beds, trucks can be driven onto the ice to spread a thin layer of sand to control pests and rejuvenate ... liquid chromatography-mass spectrometry, or a modified 4-dimethylaminocinnamaldehyde colorimetric method. Variations in extract ... Competition between canners was fierce because profits were thin. The Ocean Spray cooperative was established in 1930 through a ...
No lichen products were detected in collected samples of the species using thin-layer chromatography. The characteristics that ... The spores have a thick gelatinous layer that is 17-22 μm thick. ...
... is a method of detecting and quantifying mRNA and other long RNA molecules in a thin layer of tissue sample. Targets can be ... measuring the size of each small fragment using size-exclusion chromatography, and using that information to determine where ...
... a lichen product that can be detected using thin-layer chromatography. Feuerstein, Shirley Cunha; Lücking, Robert; Borges da ...
... such as liquid chromatography-mass spectrometry, thin-layer chromatography-mass spectrometry, Fourier-transform ion cyclotron ...
One of the first to use gas chromatography, mass spectrometry and thin layer chromatography in flavor research, Patton proved, ...
No lichen products were detected in the collected specimens using thin-layer chromatography. Astrothelium curvisporum and A. ... The lichen has a pale ochraceous-green thallus with a cortex; the thallus is surrounded by a thin (≤1 mm wide) black prothallus ...
The entire sample was analyzed by thin-layer chromatography from which 55 grams of Niebla caespitosa were later submitted (14 ... and by its relatively thin cortex, 25-50 µm thick, in contrast to 45-75 µm thick in Niebla josecuervoi, which also differs by ... undoubtedly due to the relatively thin cortex. The species will mostly likely be confused with Niebla effusa, one that differs ...
Thin layer chromatography (TLC) is performed on the supernatant, which separates out the components. Lecithin and sphingomyelin ...
Many customizations, additives, and thin additional external layers on one or both sides are often added to help with various ... Journal of Chromatography A. 315: 201-210. doi:10.1016/S0021-9673(01)90737-X. Quoted from a campaign site giving no details of ... Thin sheets of polystyrene are used in polystyrene film capacitors as it forms a very stable dielectric, but has largely fallen ... a thin insulation sheet also used for model building Although it is a closed-cell foam, both expanded and extruded polystyrene ...
Secondary chemicals in the lichen that are detectable with thin-layer chromatography include alectoronic acid (major), and ... It has a thin, shiny, pale olive-green to olive-grey thallus with numerous isidia. ...
Mars has no protective ozone layer), has built up a thin layer of a very strong oxidant. A sufficiently strong oxidizing ... October 2006). "The limitations on organic detection in Mars-like soils by thermal volatilization-gas chromatography-MS and ... Mars lacks an ozone layer, so the surface is bathed in ultraviolet) can cause carbon dioxide to react with soils to produce ...
Ehmann, A. (1977). "The van URK-Salkowski reagent - a sensitive and specific chromogenic reagent for silica gel thin-layer ... Journal of Chromatography A. 1216 (20): 4485-91. doi:10.1016/j.chroma.2009.03.026. PMID 19339019. Meudt, W. J.; Gaines, T. P. ( ... chromatographic detection and identification of indole derivatives" (PDF). Journal of Chromatography A. 132 (2): 267-276. doi: ...
Techniques available to measure blood concentrations include thin layer chromatography, gas liquid chromatography with or ...
Badr JM (January 2013). "A validated high performance thin layer chromatography method for determination of yohimbine ... "Profiling the indole alkaloids in yohimbe bark with ultra-performance liquid chromatography coupled with ion mobility ...
... contains stictic acid, a lichen product detectable using thin-layer chromatography. Feuerstein, Shirley ...
In this situation the surrounding gas layer reaches temperature equilibrium with the surface of the particle. Molecules with ... Experiments by Schafer, Kim, Vlassak and Keith suggest that photophoretic forces could levitate thin 10 centimetre-scale ... Journal of Liquid Chromatography & Related Technologies. Informa UK Limited. 20 (16-17): 2907-2929. doi:10.1080/ ... "Controlled levitation of nanostructured thin films for sun-powered near-space flight". Science Advances. 7 (7). Bibcode: ...
The triterpenes of V. ligulata, commonly referred to as T1 and T2 by their Rf values on thin-layer chromatography plates, have ...
Van Berkel, Gary J.; Sanchez, Amaury D.; Quirke, J. Martin E. (2002). "Thin-Layer Chromatography and Electrospray Mass ... Zhang, Jialing; Zhou, Zhigui; Yang, Jianwang; Zhang, Wei; Bai, Yu; Liu, Huwei (2012). "Thin Layer Chromatography/Plasma ... chromatography and imaging methods". Rapid Communications in Mass Spectrometry. 28 (16): 1779-1791. doi:10.1002/rcm.6960. ISSN ... A New Highly Sensitive Approach for Liquid Chromatography/Mass Spectrometry of Small and Large Molecules". Analytical Chemistry ...
... detection of the heteroatom silicate phosphate Dittmer's spray reagent for phospholipids is used in thin layer chromatography ... specific spray for the detection of phospholipids on thin-layer chromatograms", Dittmer, J. C., R. L. Lester. J. Lipid Res. 5 ( ...
... including but not limited to thin-layer chromatography (TLC) and high-pressure liquid chromatography. Voltammetry ... J. Planar Chromatography. 1996, 9:269. Hoekstra JC, Johnson DC. Anal. Chim. Acta. 1999, 390:45. (All articles with vague or ... It is important to note that in squarewave volammetric analyses, the diffusion layer is not renewed between potential cycles. ... the conditions present for each cycle is a complex diffusion layer which has evolved through all prior potential cycles. The ...
It is oxidized in air at about 933 K (660 °C, 1220 °F), although an oxide passivation layer forms even at room temperature. ... This report included an initial chemical examination: the thermal gradient version of the gas-chromatography method was applied ... and the beta phase usually exists as thin films obtained by magnetron sputtering, chemical vapor deposition or electrochemical ... The reactivity is not always obvious due to the rapid formation of a stable oxide layer, which prevents further reactions, ...
... and a chemical analysis with thin-layer chromatography did not find any secondary chemicals. da Silva Cáceres, Marcela Eugenia ...
... a lichen product that can be detected using thin-layer chromatography. Feuerstein, Shirley Cunha; Lücking, Robert; Borges da ... The lichen has a pale beige to whitish thallus with a thin cortex and a dark brown prothallus. It has hyaline ascospores that ...
Thin layer chromatography (TLC) is a quick alternative to more complex chromatography methods. TLC can be used to analyze inks ... In 1906 botanist Mikhail Tsvet invented paper chromatography, an early predecessor to thin layer chromatography, and used it to ... and thin layer chromatography. The range of different methods is important due to the destructive nature of some instruments ... Gas chromatography (GC) performs the same function as liquid chromatography, but it is used for volatile mixtures. In forensic ...
Thin-layer chromatography (TLC) is by far one of the most common analytical methods used to achieve purposes, and it has many ... Thin-Layer Chromatography in Food Analysis DOI link for Thin-Layer Chromatography in Food Analysis ... Thin-layer chromatography (TLC) is by far one of the most common analytical methods used to achieve purposes, and it has many ... BookPractical Thin-Layer Chromatography. Click here to navigate to parent product. ...
Thin layer chromatography of phosphoinnositides. / González Sastre, F.; Folchpi, L.. In: J. Lipid Research, Vol. 0, No. 9, ... González Sastre, F & Folchpi, L 1968, Thin layer chromatography of phosphoinnositides, J. Lipid Research, vol. 0, no. 9, pp. ... González Sastre, F. ; Folchpi, L. / Thin layer chromatography of phosphoinnositides. In: J. Lipid Research. 1968 ; Vol. 0, No. ... González Sastre F, Folchpi L. Thin layer chromatography of phosphoinnositides. J. Lipid Research. 1968 Jan 1;0(9):532-532. ...
Thin-layer chromatography (TLC). TLC was performed according to Yao and Rastetter50. A TLC plate (silica on aluminum, Sigma) ... Yao, J. K. & Rastetter, G. M. Microanalysis of complex tissue lipids by high-performance thin-layer chromatography. Anal. ... We also identified and quantified the lipids in RBC EVs, with thin layer chromatography (TLC) and matrix-assisted laser ... The authors would like to thank Tineke van Lingen for performing the thin-layer chromatography experiments and Fred MacKintosh ...
Thin layer chromatography (TLC) uses a layer of silica poured onto a glass plate as a stationary phase. The mobile phase is ... High Performance Thin Layer Chromatography (HPTLC) gives much greater resolution and separation of components than normal TLC. ... 15How can High Performance Thin Layer Chromatography (HPTLC) help your company?. ... What is Chromatography?. Chromatography is a scientific method used to separate different components in a mixture and to ...
Thin layer chromatography (TLC)-Zhejiang Scientific Instruments & Material I/E Co., Ltd. ...
This study analysis performed thin layer chromatography (TLC) method to separate the adsorption on the adsorbent thin layer. ... Determination of Capsaicin Levels in Capsicum annum Linn Ethanolic Extract using Thin Layer Chromatography Analysis. ...
23.2 What is Thin Layer Chromatography?. 23.3 What is Gas Chromatography?. 23.4 What is Column Chromatography?. 23.5 What is ... High Pressure Liquid Chromatography?. 23.6 What is Ion Chromatography?. 23.7 What is Gel Permeation Chromatography?. 23.8 What ... Chromatographic Techniques 23.1 What is Paper Chromatography?. ...
Thin Layer Chromatography. Thin layer chromatography (TLC) is a separation technique based on differential partitioning of ... Qualitative Thin Layer Chromatography Analysis Ginkgo. Qualitative Thin Layer Chromatography Analysis of Flavonoids and ... Syringe Filters for Chromatography. Syringe filter selection guide for HPLC, UHPLC, and Ion Chromatography using pore size, ... Sample preparation for analytical techniques such as HPLC, UHPLC, ion chromatography, gas chromatography, and dissolution ...
Randomly collected 110 samples from eleven Medical Officers Of Health areas in Jaffna district were analyzed by using thin ... layer chromatography and UV-visible spectrophotometry. According to the results, 100% beverages and 85% ... These nonpermitted colour spots were not detectable by paper chromatography analysis but appeared in thin layer chromatography ... Extracted colours were identified by thin layer chromatography. Extracted colour samples and colour standards were dissolved in ...
Braselton WE, Johnson M [2003]. Thin layer chromatography convulsant screen extended by gas chromatography-mass spectrometry. J ...
Colour Tests and Thin-Layer Chromatography. 16. Immunoassays. 17. Ultraviolet, Visible and Fluorescence Spectrophotometry ...
... by thin layer chromatography (TLC), dithionite (searched for but not detected in process solutions) by polarography or TLC, ... Thin layer chromatography; Volumetric analysis; Gravimetric analysis; Citrate process; Air pollution detection; Flue gas ...
Thin layer chromatography is applicable to the analysis of gastric contents and urine. In methanol / ammonia (100:1.5) the Rf ... The UV spectrum in methanol gives deltamax at 227 nm; A, = 372 (Risley & Bopp, 1990). Using thin layer chromatography, the drug ... Good chromatography over 8 minutes was obtained using C8 column with a mobile phase of triethylamine acetate (10 mL/L, pH to ... Gas chromatography can be performed without derivatization by many methods which are suitable for analysis of other ...
Thin layer chromatography-based assay of O6-methylguanine-DNA methyltransferase activity in tissue. Anal Biochem. 2010 Oct.405( ...
Quantitative thin layer chromatography for the determination of medroxyprogesterone acetate using a smartphone and open-source ...
Categories: Chromatography, Thin Layer Image Types: Photo, Illustrations, Video, Color, Black&White, PublicDomain, ...
The method described uses paper and thin-layer chromatography. Thin-layer cliromatograph3 using wide-pore silica gel ...
Purification of ABA was effected by thin layer chromatography. ABA was quantified by HPLC and enzyme linked immunosorbent assay ...
Thin-layer chromatography was performed with silica gel plates using toluene and ethyl acetate in a 1:1 proportion. The IR ...
Thin-layer chromatography and multivariate data analysis of willow bark extracts. J Chromatogr Sci. 2004;42:306-9. View ... Application of high-performance liquid chromatography for research of salicin in bark of different varieties of Salix. Medicina ...
2. Validation of fluorescent thin layer chromatography as point of care test. Preliminary results from the initial analysis of ... using the fluorescent thin layer chromatography method to detect mycolactone, has shown great potential for a rapid diagnosis ...
Reactions were monitored by thin-layer chromatography on silica gel 60 F254 plate using UV illumination at 254 nm. Column ... After removing the solvent, the resulting residue was further purified by column chromatography on silica gel using 10-30% ... chromatography was performed on silica gel (230-400 mesh), using a mixture of hexane and ethyl acetate as eluents. Nuclear ...
Currently, simpler methods such as loop-mediated isothermal amplification assay and fluorescent thin layer chromatography are ... Mycobacterium ulcerans disease diagnosis from clinical samples by fluorescence of mycolactone on thin layer chromatography. ...
... and thin-layer chromatography and hyphenated techniques thereof; sample preparation, chemometrics; and validation. The ... Liquid Chromatography (LC/HPLC)Gas Chromatography (GC)Sample PreparationMass SpectrometryPharmaceutical AnalysisEnvironmental ... View MoreLiquid Chromatography (LC/HPLC)Gas Chromatography (GC)Sample PreparationMass SpectrometryPharmaceutical Analysis ... 39th International Symposium on Capillary Chromatography (ISCC) and 12th GC×GC Symposium 2015. Ft. Worth, Texas, USA. E-mail: ...
... techniques employed for the organic analysis of lipsticks by compositional comparison include thin layer chromatography (TLC), ... Liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS), Gas chromatography-inductively coupled plasma ... gas chromatography (GC), and high-performance liquid chromatography (HPLC). These methods provide useful information regarding ... One of the primary techniques to achieve this is to separate the chemical species with high-performance liquid chromatography ( ...
High Performance Thin Layer Chromatography (HPTLC). *High Performance Liquid Chromatography (HPLC). *Gas Liquid Chromatography ...
  • 1 extraction was carried out using immunoaffinity column, separated by reversed-phase (C-18) high performance liquid chromatography (HPLC) , and quantified by fluorescence detector. (
  • Gas chromatography in combination with mass spectrometry and/or thin-layer chromatography is used to confirm positive results, especially in legal proceedings. (
  • How can High Performance Thin Layer Chromatography (HPTLC) help your company? (
  • High Performance Thin Layer Chromatography (HPTLC) gives much greater resolution and separation of components than normal TLC. (
  • Considerably much less solvent is used for mobile phase in HPTLC as compared to other chromatography techniques making it more environmentally friendly and cost effective. (
  • Randomly collected 110 samples from eleven Medical Officers Of Health areas in Jaffna district were analyzed by using thin layer chromatography and UV-visible spectrophotometry. (
  • TLC can be considered to be as powerful a determination method as gas liquid chromatography and high performance liquid chromatography in determining minor components and residue analysis of food and food products. (
  • The process involves applying a very small sample of the mixture to a solid, porous layer (stationary phase) and passing a liquid solvent (mobile phase) through this stationary phase. (
  • This study analysis performed thin layer chromatography (TLC) method to separate the adsorption on the adsorbent thin layer. (
  • Thin-layer chromatography (TLC) is by far one of the most common analytical methods used to achieve purposes, and it has many valuable analytical applications in the field of food analysis and quality control. (
  • With all types of tests mentioned, including thin-layer chromatography, false-negative results tend to be more common than false-positive results. (
  • Chromatography is a scientific method used to separate different components in a mixture and to identify key compounds of interest present in the mixture. (
  • Thin layer chromatography (TLC)_Product classification_Zhejiang Scientific Instruments & Material I/E Co., Ltd. (
  • Additive manufacturing (AM) refers to several types of processes that join materials to build objects, often layer-by-layer, from a computer-aided design file. (
  • Although they do not deplete the ozone layer, they are known to be powerful greenhouse gases and, thus, contributors to climate change. (
  • Identification of Ginkgo biloba supplements adulteration using high performance thin layer chromatography and ultra high performance liquid chromatography-diode array detector-quadrupole time of flight-mass spectrometry Avula B, Sagi S, Gafner S, Upton R, Wang YH, Wang M, Khan IA. (
  • Improved thin-layer chromatographic method in the diagnosis of mannosidosis. (
  • Definitive diagnosis of Crigler-Najjar syndrome requires high-performance liquid chromatography of bile or a tissue enzyme assay of a liver biopsy sample. (
  • Highly sensitive on-site detection of drugs adulterated in botanical dietary supplements using thin layer chromatography combined with dynamic surface enhanced Raman spectroscopy Fang F, Qi Y, Lu F, Yang L. Talanta. (
  • Detection of structurally similar adulterants in botanical dietary supplements by thin-layer chromatography and surface enhanced Raman spectroscopy combined with two-dimensional correlation spectroscopy. (