Centrifugation, Density Gradient: 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)Centrifugation: Process of using a rotating machine to generate centrifugal force to separate substances of different densities, remove moisture, or simulate gravitational effects. It employs a large motor-driven apparatus with a long arm, at the end of which human and animal subjects, biological specimens, or equipment can be revolved and rotated at various speeds to study gravitational effects. (From Websters, 10th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Centrifugation, Zonal: Centrifugation using a rotating chamber of large capacity in which to separate cell organelles by density-gradient centrifugation. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Centrifugation, Isopycnic: A technique used to separate particles according to their densities in a continuous density gradient. The sample is usually mixed with a solution of known gradient materials and subjected to centrifugation. Each particle sediments to the position at which the gradient density is equal to its own. The range of the density gradient is usually greater than that of the sample particles. It is used in purifying biological materials such as proteins, nucleic acids, organelles, and cell types.Cell Fractionation: Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.Metrizamide: A solute for density gradient centrifugation offering higher maximum solution density without the problems of increased viscosity. It is also used as a resorbable, non-ionic contrast medium.Microscopy, Electron: 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.Molecular Weight: The sum of the weight of all the atoms in a molecule.Bone Density: The amount of mineral per square centimeter of BONE. This is the definition used in clinical practice. Actual bone density would be expressed in grams per milliliter. It is most frequently measured by X-RAY ABSORPTIOMETRY or TOMOGRAPHY, X RAY COMPUTED. Bone density is an important predictor for OSTEOPOROSIS.Povidone: A polyvinyl polymer of variable molecular weight; used as suspending and dispersing agent and vehicle for pharmaceuticals; also used as blood volume expander.Ultracentrifugation: 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)Triiodobenzoic Acids: Triiodo-substituted derivatives of BENZOIC ACID.Subcellular Fractions: 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)Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Cell SeparationCell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Kinetics: The rate dynamics in chemical or physical systems.Sucrose: A nonreducing disaccharide composed of GLUCOSE and FRUCTOSE linked via their anomeric carbons. It is obtained commercially from SUGARCANE, sugar beet (BETA VULGARIS), and other plants and used extensively as a food and a sweetener.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.TritiumCesium: A member of the alkali metals. It has an atomic symbol Cs, atomic number 50, and atomic weight 132.91. Cesium has many industrial applications, including the construction of atomic clocks based on its atomic vibrational frequency.Population Density: Number of individuals in a population relative to space.Hydrogen-Ion Concentration: 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)Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Detergents: 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.Rabbits: 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.Organoids: An organization of cells into an organ-like structure. Organoids can be generated in culture. They are also found in certain neoplasms.Cattle: 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.Silicon Dioxide: 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.Solubility: 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)Cell Line: Established cell cultures that have the potential to propagate indefinitely.Filtration: A process of separating particulate matter from a fluid, such as air or a liquid, by passing the fluid carrier through a medium that will not pass the particulates. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Cells, Cultured: 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.Electrophoresis: 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.Methods: A series of steps taken in order to conduct research.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Macromolecular Substances: 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.Diatrizoate: A commonly used x-ray contrast medium. As DIATRIZOATE MEGLUMINE and as Diatrizoate sodium, it is used for gastrointestinal studies, angiography, and urography.Octoxynol: 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.Lysosomes: 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)Chromatography: 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.Temperature: 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.Nucleotidases: A class of enzymes that catalyze the conversion of a nucleotide and water to a nucleoside and orthophosphate. EC 3.1.3.-.Densitometry: The measurement of the density of a material by measuring the amount of light or radiation passing through (or absorbed by) the material.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Lipoproteins, LDL: A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.Molecular Sequence Data: 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.Lipoproteins, HDL: A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.Cytoplasmic Granules: Condensed areas of cellular material that may be bounded by a membrane.DNA: 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).Lipoproteins: Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.Amino Acids: 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.Spermatozoa: Mature male germ cells derived from SPERMATIDS. As spermatids move toward the lumen of the SEMINIFEROUS TUBULES, they undergo extensive structural changes including the loss of cytoplasm, condensation of CHROMATIN into the SPERM HEAD, formation of the ACROSOME cap, the SPERM MIDPIECE and the SPERM TAIL that provides motility.Phospholipids: 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.Membranes: Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Rats, Inbred Strains: 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.Cholesterol: The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.Biological Transport: The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.Microsomes: 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)Chemical Precipitation: 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.Escherichia coli: 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.Organelles: 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.Intracellular Membranes: 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.Carbon Isotopes: Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.Chromatography, DEAE-Cellulose: 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)Polyethylene Glycols: 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.Magnesium: 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.Proteins: 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.Chemical Fractionation: 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)Phosphorus Isotopes: Stable phosphorus atoms that have the same atomic number as the element phosphorus, but differ in atomic weight. P-31 is a stable phosphorus isotope.Chlorides: Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.Cytoplasm: 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)Cell Nucleus: Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.Amino Acid Sequence: 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.Membrane Microdomains: Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.Lipoproteins, VLDL: A class of lipoproteins of very light (0.93-1.006 g/ml) large size (30-80 nm) particles with a core composed mainly of TRIGLYCERIDES and a surface monolayer of PHOSPHOLIPIDS and CHOLESTEROL into which are imbedded the apolipoproteins B, E, and C. VLDL facilitates the transport of endogenously made triglycerides to extrahepatic tissues. As triglycerides and Apo C are removed, VLDL is converted to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LOW-DENSITY LIPOPROTEINS from which cholesterol is delivered to the extrahepatic tissues.Acid Phosphatase: An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.2.Chromatography, Affinity: 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)Cell-Free System: A fractionated cell extract that maintains a biological function. A subcellular fraction isolated by ultracentrifugation or other separation techniques must first be isolated so that a process can be studied free from all of the complex side reactions that occur in a cell. The cell-free system is therefore widely used in cell biology. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p166)ThymidineCytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.Models, Biological: 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.Protein Binding: 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.Adenosine Triphosphatases: A group of enzymes which catalyze the hydrolysis of ATP. The hydrolysis reaction is usually coupled with another function such as transporting Ca(2+) across a membrane. These enzymes may be dependent on Ca(2+), Mg(2+), anions, H+, or DNA.Apolipoproteins: Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.Ribonucleases: Enzymes that catalyze the hydrolysis of ester bonds within RNA. EC 3.1.-.Chromatography, Ion Exchange: 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.Electrophoresis, Agar Gel: Electrophoresis in which agar or agarose gel is used as the diffusion medium.Ficoll: A sucrose polymer of high molecular weight.Culture Techniques: Methods of maintaining or growing biological materials in controlled laboratory conditions. These include the cultures of CELLS; TISSUES; organs; or embryo in vitro. Both animal and plant tissues may be cultured by a variety of methods. Cultures may derive from normal or abnormal tissues, and consist of a single cell type or mixed cell types.Hypergravity: Condition wherein the force of gravity is greater than or is increased above that on the surface of the earth. This is expressed as being greater than 1 g.Immune Sera: Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.UridineSperm Motility: Movement characteristics of SPERMATOZOA in a fresh specimen. It is measured as the percentage of sperms that are moving, and as the percentage of sperms with productive flagellar motion such as rapid, linear, and forward progression.Polyribosomes: A multiribosomal structure representing a linear array of RIBOSOMES held together by messenger RNA; (RNA, MESSENGER); They represent the active complexes in cellular protein synthesis and are able to incorporate amino acids into polypeptides both in vivo and in vitro. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Erythrocyte Aging: The senescence of RED BLOOD CELLS. Lacking the organelles that make protein synthesis possible, the mature erythrocyte is incapable of self-repair, reproduction, and carrying out certain functions performed by other cells. This limits the average life span of an erythrocyte to 120 days.Immunodiffusion: Technique involving the diffusion of antigen or antibody through a semisolid medium, usually agar or agarose gel, with the result being a precipitin reaction.Culture Media: 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.RNA, Messenger: 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.Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Microbodies: Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.RNA: A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Digitonin: A glycoside obtained from Digitalis purpurea; the aglycone is digitogenin which is bound to five sugars. Digitonin solubilizes lipids, especially in membranes and is used as a tool in cellular biochemistry, and reagent for precipitating cholesterol. It has no cardiac effects.Lipids: 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)Ribosomes: Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.Electrophoresis, Disc: Electrophoresis in which discontinuities in both the voltage and pH gradients are introduced by using buffers of different composition and pH in the different parts of the gel column. The term 'disc' was originally used as an abbreviation for 'discontinuous' referring to the buffers employed, and does not have anything to do with the shape of the separated zones.Carbohydrates: 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.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Golgi Apparatus: 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)Adenosine Triphosphate: 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.Phosphotungstic Acid: Tungsten hydroxide oxide phosphate. A white or slightly yellowish-green, slightly efflorescent crystal or crystalline powder. It is used as a reagent for alkaloids and many other nitrogen bases, for phenols, albumin, peptone, amino acids, uric acid, urea, blood, and carbohydrates. (From Merck Index, 11th ed)Calcium: 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.Nucleic Acid Renaturation: The reformation of all, or part of, the native conformation of a nucleic acid molecule after the molecule has undergone denaturation.Species Specificity: 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.Fluorescent Antibody Technique: 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.Cell Compartmentation: A partitioning within cells due to the selectively permeable membranes which enclose each of the separate parts, e.g., mitochondria, lysosomes, etc.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Swine: 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).Denaturing Gradient Gel Electrophoresis: Electrophoresis in which various denaturant gradients are used to induce nucleic acids to melt at various stages resulting in separation of molecules based on small sequence differences including SNPs. The denaturants used include heat, formamide, and urea.Viruses, Unclassified: Viruses whose taxonomic relationships have not been established.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Sonication: The application of high intensity ultrasound to liquids.Osmolar Concentration: 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.Deoxyribonucleases: Enzymes which catalyze the hydrolases of ester bonds within DNA. EC 3.1.-.DNA, Circular: Any of the covalently closed DNA molecules found in bacteria, many viruses, mitochondria, plastids, and plasmids. Small, polydisperse circular DNA's have also been observed in a number of eukaryotic organisms and are suggested to have homology with chromosomal DNA and the capacity to be inserted into, and excised from, chromosomal DNA. It is a fragment of DNA formed by a process of looping out and deletion, containing a constant region of the mu heavy chain and the 3'-part of the mu switch region. Circular DNA is a normal product of rearrangement among gene segments encoding the variable regions of immunoglobulin light and heavy chains, as well as the T-cell receptor. (Riger et al., Glossary of Genetics, 5th ed & Segen, Dictionary of Modern Medicine, 1992)Trypsin: 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.Chemistry: A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.Mutation: 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.Nucleoproteins: Proteins conjugated with nucleic acids.Biological Transport, Active: The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.Chemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.Nucleic Acid Denaturation: Disruption of the secondary structure of nucleic acids by heat, extreme pH or chemical treatment. Double strand DNA is "melted" by dissociation of the non-covalent hydrogen bonds and hydrophobic interactions. Denatured DNA appears to be a single-stranded flexible structure. The effects of denaturation on RNA are similar though less pronounced and largely reversible.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Mitochondria: 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)Pronase: A proteolytic enzyme obtained from Streptomyces griseus.Edetic Acid: A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.Nucleic Acid Hybridization: Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)Colloids: Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other.Complement Fixation Tests: Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.Sodium Dodecyl Sulfate: An anionic surfactant, usually a mixture of sodium alkyl sulfates, mainly the lauryl; lowers surface tension of aqueous solutions; used as fat emulsifier, wetting agent, detergent in cosmetics, pharmaceuticals and toothpastes; also as research tool in protein biochemistry.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Bacterial Proteins: Proteins found in any species of bacterium.Glucose-6-Phosphatase: An enzyme that catalyzes the conversion of D-glucose 6-phosphate and water to D-glucose and orthophosphate. EC 3.1.3.9.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.Microscopy, Immunoelectron: 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.Proteoglycans: Glycoproteins which have a very high polysaccharide content.Plants: Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.Reticulocytes: Immature ERYTHROCYTES. In humans, these are ERYTHROID CELLS that have just undergone extrusion of their CELL NUCLEUS. They still contain some organelles that gradually decrease in number as the cells mature. RIBOSOMES are last to disappear. Certain staining techniques cause components of the ribosomes to precipitate into characteristic "reticulum" (not the same as the ENDOPLASMIC RETICULUM), hence the name reticulocytes.Dogs: 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)Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.Urate Oxidase: An enzyme that catalyzes the conversion of urate and unidentified products. It is a copper protein. The initial products decompose to form allantoin. EC 1.7.3.3.Chick Embryo: The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.Viral Proteins: Proteins found in any species of virus.Carbon Radioisotopes: Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Staining and Labeling: The marking of biological material with a dye or other reagent for the purpose of identifying and quantitating components of tissues, cells or their extracts.Peptides: 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.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Brain: 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.Bromides: Salts of hydrobromic acid, HBr, with the bromine atom in the 1- oxidation state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Surface-Active Agents: Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics.Rats, Sprague-Dawley: 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.Immunoblotting: 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.Microvilli: Minute projections of cell membranes which greatly increase the surface area of the cell.Physicochemical Phenomena: The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.Blotting, Western: 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.Chemistry, Physical: The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.Potassium: 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.Freezing: Liquids transforming into solids by the removal of heat.Virion: The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.Autoradiography: 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)Rubella virus: The type (and only) species of RUBIVIRUS causing acute infection in humans, primarily children and young adults. Humans are the only natural host. A live, attenuated vaccine is available for prophylaxis.Chemistry Techniques, Analytical: Methodologies used for the isolation, identification, detection, and quantitation of chemical substances.Histocytochemistry: Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Liposomes: 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.Endoplasmic Reticulum: 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)DNA Replication: The process by which a DNA molecule is duplicated.Sulfates: Inorganic salts of sulfuric acid.Succinate Dehydrogenase: A flavoprotein containing oxidoreductase that catalyzes the dehydrogenation of SUCCINATE to fumarate. In most eukaryotic organisms this enzyme is a component of mitochondrial electron transport complex II.Isoelectric Focusing: 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.Mitochondria, Liver: Mitochondria in hepatocytes. As in all mitochondria, there are an outer membrane and an inner membrane, together creating two separate mitochondrial compartments: the internal matrix space and a much narrower intermembrane space. In the liver mitochondrion, an estimated 67% of the total mitochondrial proteins is located in the matrix. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p343-4)Receptors, Cell Surface: 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.Antibodies: 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).Buffers: A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.Semen: The thick, yellowish-white, viscid fluid secretion of male reproductive organs discharged upon ejaculation. In addition to reproductive organ secretions, it contains SPERMATOZOA and their nutrient plasma.Chickens: 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.Guinea Pigs: 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.Antigen-Antibody Complex: The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.Dialysis: A process of selective diffusion through a membrane. It is usually used to separate low-molecular-weight solutes which diffuse through the membrane from the colloidal and high-molecular-weight solutes which do not. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.beta-Cyclodextrins: Cyclic GLUCANS consisting of seven (7) glucopyranose units linked by 1,4-glycosidic bonds.Protein Conformation: 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).Neutrophils: Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.

The exocyst is an effector for Sec4p, targeting secretory vesicles to sites of exocytosis. (1/7983)

Polarized secretion requires proper targeting of secretory vesicles to specific sites on the plasma membrane. Here we report that the exocyst complex plays a key role in vesicle targeting. Sec15p, an exocyst component, can associate with secretory vesicles and interact specifically with the rab GTPase, Sec4p, in its GTP-bound form. A chain of protein-protein interactions leads from Sec4p and Sec15p on the vesicle, through various subunits of the exocyst, to Sec3p, which marks the sites of exocytosis on the plasma membrane. Sec4p may control the assembly of the exocyst. The exocyst may therefore function as a rab effector system for targeted secretion.  (+info)

Studies on a nonpolysomal ribonucleoprotein coding for myosin heavy chains from chick embryonic muscles. (2/7983)

A messenger ribonucleoprotein (mRNP) particle containing the mRNA coding for the myosin heavy chain (MHC mRNA) has been isolated from the postpolysomal fraction of homogenates of 14-day-old chick embryonic muscles. The mRNP sediments in sucrose gradient as 120 S and has a characteristic buoyant density of 1.415 g/cm3, which corresponds to an RNA:protein ratio of 1:3.8. The RNA isolated from the 120 S particle behaved like authentic MHC mRNA purified from chick embryonic muscles with respect to electrophoretic mobility and ability to program the synthesis of myosin heavy chain in a rabbit reticulocyte lysate system as judged by multi-step co-purification of the in vitro products with chick embryonic leg muscle myosin added as carrier. The RNA obtained from the 120 S particle was as effective as purified MHC mRNA in stimulating the synthesis of the complete myosin heavy chains in rabbit reticulocyte lysate under conditions where non-muscle mRNAs had no such effect. Analysis of the protein moieties of the 120 S particle by sodium dodecyl sulfate-polyacrylamide gel electrophoresis shows the presence of seven distinct polypeptides with apparent molecular weights of 44,000, 49,000, 53,000, 81,000, 83,000, and 98,000, whereas typical ribosomal proteins are absent. These results indicate that the 120 S particles are distinct cellular entities unrelated to ribosomes or initiation complexes. The presence of muscle-specific mRNAs as cytoplasmic mRNPs suggests that these particles may be involved in translational control during myogenesis in embryonic muscles.  (+info)

Characterization of nuclear structures containing superhelical DNA. (3/7983)

Structures resembling nuclei but depleted of protein may be released by gently lysing cells in solutions containing non-ionic detergents and high concentrations of salt. These nucleoids sediment in gradients containing intercalating agents in a manner characteristic of DNA that is intact, supercoiled and circular. The concentration of salt present during isolation of human nucleoids affects their protein content. When made in I-95 M NaCl they lack histones and most of the proteins characteristic of chromatin; in 1-0 M NaCl they contain variable amounts of histones. The effects of various treatments on nucleoid integrity were investigated.  (+info)

Isocitrate lyase of Ashbya gossypii--transcriptional regulation and peroxisomal localization. (4/7983)

The isocitrate lyase-encoding gene AgICL1 from the filamentous hemiascomycete Ashbya gossypii was isolated by heterologous complementation of a Saccharomyces cerevisiae icl1d mutant. The open reading frame of 1680 bp encoded a protein of 560 amino acids with a calculated molecular weight of 62584. Disruption of the AgICL1 gene led to complete loss of AgIcl1p activity and inability to grow on oleic acid as sole carbon source. Compartmentation of AgIcl1p in peroxisomes was demonstrated both by Percoll density gradient centrifugation and by immunogold labeling of ultrathin sections using specific antibodies. This fitted with the peroxisomal targeting signal AKL predicted from the C-terminal DNA sequence. Northern blot analysis with mycelium grown on different carbon sources as well as AgICL1 promoter replacement with the constitutive AgTEF promoter revealed a regulation at the transcriptional level. AgICL1 was subject to glucose repression, derepressed by glycerol, partially induced by the C2 compounds ethanol and acetate, and fully induced by soybean oil.  (+info)

Mass spectral study of polymorphism of the apolipoproteins of very low density lipoprotein. (5/7983)

New isoforms of apolipoprotein (apo)C-I and apoC-III have been detected in delipidated fractions from very low density lipoprotein (VLDL) using matrix-assisted laser desorption (MALDI) and electrospray ionization (ESI) mass spectrometry (MS). The cleavage sites of truncated apoC-III isoforms have also been identified. The VLDL fractions were isolated by fixed-angle single-spin ultracentrifugation using a self-generating sucrose density gradient and delipidated using a newly developed C18 solid phase extraction protocol. Fifteen apoC isoforms and apoE were identified in the MALDI spectra and the existence of the more abundant species was verified by ESI-MS. The relative intensities of the apoCs are closely correlated in three normolipidemic subjects. A fourth subject with type V hyperlipidemia exhibited an elevated apoC-III level and a suppressed level of the newly discovered truncated apoC-I isoform. ApoC-II was found to be particularly sensitive to in vitro oxidation. The dynamic range and specificity of the MALDI assay shows that the complete apoC isoform profile and apoE phenotype can be obtained in a single measurement from the delipidated VLDL fraction.  (+info)

Purification and characterization of rat hippocampal CA3-dendritic spines associated with mossy fiber terminals. (6/7983)

We report a revised and improved isolation procedure for CA3-dendritic spines, most of them still in association with mossy fiber terminals resulting in a 7.5-fold enrichment over nuclei and a 29-fold enrichment over myelin. Additionally, red blood cells, medullated fibers, mitochondria and small synaptosomes were significantly depleted. We show by high resolution electron microscopy that this subcellular fraction contains numerous dendritic spines with a rich ultrastructure, e.g. an intact spine apparatus, membranous organelles, free and membrane-bound polyribosomes, endocytic structures and mitochondria. This improved experimental system will allow us to study aspects of post-synaptic functions at the biochemical and molecular level.  (+info)

Two types of HTLV-1 particles are released from MT-2 cells. (7/7983)

The MT-2 cell line transformed by human T-cell leukemia virus type 1 (HTLV-1) contains one complete provirus and seven defective proviruses. Four defective genomes have an identical structure (LTR-MA-deltaCA-pX-LTR) with an open reading frame that spans from MA to pX, giving rise to a 3.4-kb (24S) RNA transcript encoding a chimeric Gag-pX protein, p28. MT-2 cells release two distinct types of virions. The major "classic" type of particle has a buoyant density of 1.155-1.16 g/cm3 and contains the standard HTLV-I structural proteins and reverse transcriptase (RT). In addition, about 5% of particles are "light," approximately 1.12 g/cm3, and contain p28, RT activity, and the 3.4-kb RNA transcript. RT-PCR and in vitro translation indicate that some of the classic HTLV-1 particles package 3.4-kb RNA as well as full-length 8.5-kb RNA. In addition to matrix features, the p28 protein has a motif resembling a zinc finger at the C-terminal, pX0 region, which may play a role in the assembly of the defective light virions.  (+info)

Subcellular localization of oestrogen-induced uterine peroxidase. (8/7983)

The distribution of oestrogen-induced peroxidase in the resuspended 8000g pellet of rat uterine homogenates was examined by centrifugation in a sucrose density gradient. Within 10h of treatment with oestradiol, peroxidase activity was found in a region devoid of catalase or urate oxidase (peroxisomal markers) which did not overlap the fractions containing succinate dehydrogenase (mitochondrial marker) or acid phosphatase (lysosomal marker). The induced uterine enzyme was localized in reticular membrane-bound vesicles with isopycnic density of 1.28g/ml from which it could be released by treatment with detergent.  (+info)

Video articles in JoVE about centrifugation density gradient include Characterization and Isolation of Mouse Primary Microglia by Density Gradient Centrifugation, DNA Extraction from 0.22 μM Sterivex Filters and Cesium Chloride Density Gradient Centrifugation, Protocol for Isolation of Primary Human Hepatocytes and Corresponding Major Populations of Non-parenchymal Liver Cells, A New Approach for the Comparative Analysis of Multiprotein Complexes Based on 15N Metabolic Labeling and Quantitative Mass Spectrometry, Isolation of Intact Mitochondria from Skeletal Muscle by Differential Centrifugation for High-resolution Respirometry Measurements, Preparation of Liquid-exfoliated Transition Metal Dichalcogenide Nanosheets with Controlled Size and Thickness: A State of the Art Protocol, Isolation of Cellular Lipid Droplets: Two Purification Techniques Starting from Yeast Cells and Human Placentas, Cloning and Large-Scale Production of High-Capacity Adenoviral Vectors Based on the Human
An investigation of the distribution of immunoglobulins in the external secretions of the hamster revealed the predominance of γA. Only γA was found in saliva, whereas colostrum and urine both contained γ2 in addition to γA. Hamster γA was present in the serum at concentrations that were insufficient to allow its visualization by routine immunoelectrophoresis. No differences in electrophoretic mobility were found between serum and secretory γA regardless of derivation. The secretory γA from saliva, colostrum and urine had sedimentation characteristics intermediate between serum γA and 19S markers in sucrose density gradient ultracentrifugation studies. Similar results were obtained on Sephadex G-200 gel filtration. Isolated secretory γA had an s020,w of 15.2S. Mild reductive procedures did not appear to alter the sedimentation characteristics of this molecule. No antigenic differences were found between serum, salivary, colostral and urinary γA.. ...
Sigma-Aldrich offers Sigma-D1556, OptiPrep™ Density Gradient Medium for your research needs. Find product specific information including CAS, MSDS, protocols and references.
... - Isolation of cells, cell organelles, subcellular membranes, viruses and macromolecules using centrifugation techniques
Transcriptional regulation has been the main focus for gene regulation in the past. However, a tremendous amount of evidence from recent studies also indicates that translational regulation plays a key role during development, cell cycle control, and mechanisms related to acute drug resistance. Gene expression analysis on actively translated mRNA transcripts provides a unique approach to study post transcriptional regulation. Previous studies have relied on a traditional sucrose gradient ultracentrifugation procedure to isolate polysome complexes and requires a large amount of cells (up to 500 million cells). As a result, this still remains a major bottleneck for the investigation of post transcriptional regulation with limited quantities of clinical samples. Therefore, there is an urgent need to develop a novel approach to isolate actively translated polysomes from a small number of cells (10 to 500 cells). The new approach will allow us to systematically study potential translational ...
Blinded analyses of the concentrations of binding proteins for retinol and retinoic acid (CRABP) in homogenates of cancer and normal tissue aliquots obtained from human cervix, endometrium, ovary, breast, and lung were carried out by the sucrose gradient ultracentrifugation technique. In carcinomas of the cervix and endometrium, CRABP mean values of 50.4 and 123.2 pmol/g tissue, respectively, were detected. Such concentrations represent a 3- and 4-fold increase over the mean values of CRABP in the normal cervix (16.9 pmol/g) and normal endometrium (30.8 pmol/g), respectively. In carcinomas of the ovary, the mean CRABP level was 128.6 pmol/g compared to a maximal mean value of ≦0.46 pmol/g in the normal ovary. Elevated levels of CRABP were also found in breast and lung carcinomas compared to the amounts detected in the same patient in normal tissue aliquots of the same organ.. The differences between CRABP concentrations in cervical, endometrial, ovarian, and breast carcinomas and those in ...
In order to study the release of ATP from a neuronal preparation thought to be "purinergic," isolated varicosities were prepared from myenteric plexus by mincing and homogenizing the longitudinal muscle of guinea pig ileum in 0.32 M sucrose. The presence of varicosities within the crude preparation (P2), isolated by differential centrifugation, was confirmed by electron microscopy and by the presence of occluded lactate dehydrogenase as a cytoplasmic marker. Varicosities were purified further from the P2 fraction on a discontinuous sucrose density gradient and characterized morphologically. Varicosities resembling cholinergic, "purinergic," and adrenergic axonal terminals were identified. The release of ATP from both crude and purified varicosities was detected by monitoring the light produced when the released ATP reacted with firefly luciferin-luciferase which was present in the incubation medium. Elevated extracellular K+ or Rb+ caused the release of ATP, whereas elevated Na+ and Li+ did not. ...
Assays detecting antigen (Ag)-specific T-cell responses in immune-mediated processes are increasingly employed to understand disease pathogenesis and "immune staging". The quantity and quality of starting peripheral blood mononuclear cell (PBMC) preparations are important factors in the performance of such assays. We therefore compared final PBMC yield and function by modifying parameters at the blood drawing, storage and processing steps. While drawing blood in vacuum-driven tubes or syringes and separating PBMCs on density gradients using standard or membrane (Leucosep (R)) tubes made no difference, storing tubes for 18 h without any agitation led to PBMC preparations contaminated with granulocytes and decreased interferon (IFN)-gamma enzyme-linked immunospot (ELISpot) responses. Even agitated blood showed a trend towards reduced ELISpot responses and increased human leukocyte Ag (HLA) multimer readouts when stored for 18 h compared to 3 h. These changes were reduced by diluting blood prior to ...
Constitutive secretory vesicles carrying heparan sulfate proteoglycan (HSPG) were identified in isolated rat hepatocytes by pulse-chase experiments with [35S]sulfate and purified by velocity-controlled sucrose gradient centrifugation followed by equilibrium density centrifugation in Nycodenz. Using this procedure, the vesicles were separated from plasma membranes, Golgi, trans-Golgi network (TGN), ER, endosomes, lysosomes, transcytotic vesicles, and mitochondria. The diameter of these vesicles was approximately 100-200 nm as determined by electron microscopy. A typical coat structure as described for intra-Golgi transport vesicles or clathrin-coated vesicles could not be seen, and the vesicles were not associated with the coat protein beta-COP. Furthermore, the vesicles appear to represent a low density compartment (1.05-1.06 g/ml). Other constitutively secreted proteins (rat serum albumin, apolipoprotein E, and fibrinogen) could not be detected in purified HSPG-carrying vesicles, but banded in ...
The dynamics of the flow inside an evaporating sessile droplet of water with polystyrene micro-spheres of 1.0 μm in diameter in suspension is described. The initial volume of the droplets is in the ra
Cytochrome P-450 in rat liver nuclear membranes of untreated, PB-pretreated, or 3-MC-pretreated animals was spectrally similar to corresponding liver microsomes. Epoxide hydrase activity of liver nuclear membrane and microsomes was induced by PB administration; 3-MC did not cause any induction. The same results were obtained when either the DNase digestion method or sucrose density centrifugation technique for preparation of nuclear membranes was used.. ...
Total CD4+ Th cells from IRF4+/+ or −/− mice were purified using the first steps of the multisort kit (Miltenyi Biotec) as described previously (5). 106/ml of purified Th cells were stimulated in vitro for 72 h with 5 μg/ml of immobilized anti-CD3 mAb, 2.5 μg/ml of soluble anti-CD28 mAb (BD Biosciences), or 100 U/ml of recombinant human IL-2 as described previously (5). After a resting period of 48-72 h in the absence of anti-CD3 mAb, but in the presence of IL-2, viable cells were purified on a Ficoll density gradient and restimulated in the presence of IL-2 either with anti-CD3 (immobilized at 5 μg/ml) or with 1 μg/ml of soluble anti-Fas mAb Jo2 (Becton Dickinson) together with 2 μg/ml of protein G (Sigma-Aldrich). Apoptosis was analyzed by annexin V and propidium iodide (PI) staining as described previously (12) at the indicated times after secondary stimulation. Viable as well as dead cells were included in this analysis according to forward and side scatter characteristics. The role ...
Equilibrium sedimentation uses a gradient of a solution to separate particles based on their individual densities (mass/volume). A pivotal aspect about this type of sedimentation is that it is completely independent of the shape of the molecule. It is used to purify the differential centrifugation. A solution is prepared with the densest portion of the gradient at the bottom. Particles to be separated are then added to the gradient and centrifuged. Each particle proceeds until it reaches an environment of comparable density. Such a density gradient may be continuous or prepared in an incremental fashion. For instance, when using sucrose to prepare density gradients, one can carefully float a solution of 40% sucrose onto a layer of 45% sucrose and add further less dense layers above. The homogenate, prepared in a dilute buffer and centrifuged briefly to remove tissue and unbroken cells, is then layered on top. After centrifugation typically for an hour at about 100,000 x g, disks of cellular ...
We investigated the function of Cav1. 4 MgCl2. The intracellular alternative included (in millimeter focus) 130 beliefs < .05 were considered significant. Outcomes Sucrose-density lean fractionation of protein involved in depolarization-induced insulin release in Inches-1 Cav1 and cells.2/II-III cells The KATP funnel, made up of Kir6.2 and SUR1 subunits, has a central function in the insulin release stimulated by blood sugar and sulfonylureas. The localization was examined by us of Kir6.2, SUR1, and EPAC2 in lipid rafts by fractionating the Triton A100-insoluble part of Cav1 and Inches-1.2/II-III cell lysates in discontinuous sucrose gradients. EPAC2 is normally reported to interact straight with both Piccolo (21) and SUR1 (19), and we discovered that both EPAC2 and SUR1 are extremely focused in lipid number fractions of sucrose gradients (the user interface of 5% and 30% sucrose) in both Inches-1 cells and Cav1.2/II-III cells (Figure 1). We assessed the localization of the KATP funnel subunit ...
We investigated the function of Cav1. 4 MgCl2. The intracellular alternative included (in millimeter focus) 130 beliefs < .05 were considered significant. Outcomes Sucrose-density lean fractionation of protein involved in depolarization-induced insulin release in Inches-1 Cav1 and cells.2/II-III cells The KATP funnel, made up of Kir6.2 and SUR1 subunits, has a central function in the insulin release stimulated by blood sugar and sulfonylureas. The localization was examined by us of Kir6.2, SUR1, and EPAC2 in lipid rafts by fractionating the Triton A100-insoluble part of Cav1 and Inches-1.2/II-III cell lysates in discontinuous sucrose gradients. EPAC2 is normally reported to interact straight with both Piccolo (21) and SUR1 (19), and we discovered that both EPAC2 and SUR1 are extremely focused in lipid number fractions of sucrose gradients (the user interface of 5% and 30% sucrose) in both Inches-1 cells and Cav1.2/II-III cells (Figure 1). We assessed the localization of the KATP funnel subunit ...
Results. Western blot analysis of PKCα and PKCγ translocation. N/N 1003A cells were treated with 200 nM TPA (a conventional PKC activator) for 60 min, 10 ng/ml EGF, or 15 ng/ml bFGF. Confluent cells were taken up in ice cold 50 mM Tris, 20 mM MgCl2, 25 μg/ml aprotinin, and 25 μg/ml leupeptin, pH 7.5 and sonicated. The lysate was spun down for 60 min at 35,000 rpm (100,000x g). Western blot analysis was performed on the pellet that contained plasma membrane and the supernatant that contained cytosolic components.. Upon activation by TPA, PKCα and PKCγ should translocate from the cytosol to the plasma membrane [25]. In order to determine if PKCα and PKCγ translocate to the plasma membrane in N/N 1003A cells upon activation, TPA was added to the cell culture media for 60 min. PKCα did translocate to the membrane (pellet fraction) upon activation of the enzyme by TPA (Figure 1A, lane 2 versus lane 4). PKCγ also translocated to the membrane (pellet fraction, Figure 1B, lane 2 versus lane ...
The present invention relates to methods of enriching for desired cell population from cell sources, such as body fluids, dispersed tissue specimens and cultured cells. In particular, the present inve
As of today, there are 39 hydrogen fueling stations in the U.S., all but four of them in the state of California. They serve roughly 39 million Californians, whereas 284 million Americans outside the state have no access to hydrogen fuel-cell cars nor stations at which to refill them. Germany, on the other hand, has 83 million residents-and 45...
... : Designed for use in sucrose density gradient centrifugation, gradient gel electrophoresis, and li
Sucrose density gradient centrifugation& recover fractions-,SDS-PAGE(10% gel) (GM1 would migrate with the dye front)-,electro-transfer to nitrocellulose (or PVDF) membrane -,blocking with 4% skimmilk for 30min-, incubate with Ctx-HRP in 4% skimmilk for 1h-,wash PBS-Tween x 3times-,Detection with ECL. ...
pluriSelect separation tubes have been developed for optimal separation of leukocytes and peripheral blood mononuclear cells (PBMC) from whole blood and bone marrow. pluriMate and TwinSpin prevents you from time-consuming and laborious overlaying of the sample material. During centrifugation, Leukocytes, lymphocytes and PBMCs are separated from unwanted erythrocytes and granulocytes, depending on the density gradient media ...
try using percol gradient centrifugation. ive forgotten the manufacturer. they do have protocols for separating live/dead cells. you will have to optimize the percol density(s) for your type of cells. you may also have to use more than one density gradient of percol to separate the layers of dead and live cells.good luck. john. ...
Studies on the composition and structure of plant viruses can only be attempted after their purification from infected tissue homogenates. Owing to their intrinsic differences, however, the ease with which different viruses can be purified varies considerably. A few relatively stable viruses, e.g. tobacco mosaic virus or turnip yellow mosaic virus, can be treated with high concentrations of salt and precipitated by acid or alcohol without inactivation. With less stable viruses such methods are usually unsuccessful. The particles of such viruses, however, can be sedimented by ultracentrifugation and procedures developed frequently involve two treatments: (a) differential centrifugation and concentration after initial clarification of buffered homogenates such as with organic solvents (Steere, 1956; Tomlinson, Shepherd & Walker, 1959; Wetter, 1960), (b) further fractionation by rate or equilibrium density gradient centrifugation as developed by Brakke (1960). Because of the small capacity of the
The molecular nature and replicative behavior of R factor 222 was examined in Proteus mirabilis . In deoxyribonucleic acid (DNA} from R+ P. mirabilis , R factor 222 was identified by CsCl density gradient centrifugation as 2 satellite DNA bands at densities corresponding to 50 and 58 moles percent guanine plus cytosine (% GC) . Replication of the 50 and 58% GC components of R factor 222 in P. mirabilis was analyzed during growth in the presence and absence of chloramphenicol (CAM} and after shifting exponentialand stationary- phase cells to conditions which inhibit host protein or DNA synthesis . CAM reduced the cellular growth rate but increased the amount of both R factor components relative to host chromosomal DNA . However, the 58% GC component showed a larger proportionate increase. This was inferred to indicate reduced synthesis of an inhibitor that acts on both R factor components and an initiator required for replication of the 50% GC component . Replicative patterns observed after shifting
Molecular Cloning, also known as Maniatis, has served as the foundation of technical expertise in labs worldwide for 30 years. No other manual has been so popular, or so influential.
On Wed, 30 Sep 1998, Patrick wrote: , Hi all. , , A request from first-time user of CsCl/EtBr for plant DNA purification: , Upon addition of ethidium bromide to my phenol/chloroform purified , Plant-DNA solution in CsCl, I observe a change of color from normal , orange-red to light cherry red. If I remember correctly this was also the case, when I have purified DNA with CsCl density gradient centrifugation. , Check http://www.biologie.uni-ulm.de/bio2/knoop/images/ethidium.jpg , for visual impression... Unfortunatly my display doesnt show the correct colours. , After centrifugation color accumulated COMPLETELY with a sluggish , material on top of the gradient. Considering the possibility that some , remaining protein/polysaccharides may be responsible for this, I have , taken the remainder of clear solution and repeated the EtBr addition. No , improvement - same color change (even after repeating this for the 4th , time!) , , Anybody ideas what is going on? , I dont know, what is going on, but ...
A simple technique is described for the isolation of Toxoplasma gondii tissue cysts from fetal ovine brain by centrifugation on a discontinuous density gradient of 30 per cent and 90 per cent Percoll (colloidal silica solution). Brain samples from 51 aborted ovine fetuses were examined by both the Percoll and mouse inoculation techniques; eight infections were detected by the Percoll technique compared to 12 by mouse inoculation. Possible reasons for this discrepancy and the scope for improving the Percoll technique are discussed.. ...
An analytical ultracentrifluge was used to characterize the behaviors of ultracentrifugal sedimentation of bovine serum albumin solutions. We obtained data both for the sedimentation velocity and for the growth rate of the sediment that accumulates during ultracentrifugation. Effects of the rotor speed, the solution concentration, and the volume of the solution contained in the cell on the sedimentation behaviors were investigated experimentally. The sedimentation behaviors and the properties of the compressible sediment were explained well in terms of the theory which has been applied with respect to particulate suspension. Finally, it was shown that such factors of the solution environment as the solution pH and the salt concentration have a large effect on the sedimentation behaviors.. ...
Outer-arm dynein purified from trout spermatozoa was disrupted by low-ionic-strength dialysis, and the resulting subunits were separated by sucrose density-gradient centrifugation. The intact 19 S dynein, containing the alpha- an beta-heavy chains, intermediate chains (ICs) 1-5 and light chains (LCs) 1-6, yielded several discrete particles: a 17.5 S adenosine triphosphatase (ATPase) composed of the alpha- and beta-chains ICs 3-5 and LC 1; a 9.5 S complex containing ICs 1 and 2 together with LCs 2, 3, 4, and 6; and a single light chain (LC 5), which sedimented at approximately 4 S. In some experiments, ICs 3-5 also separated from the heavy chain complex and were obtained as a distinct subunit. Further dissociation of the 17.5 S particle yielded a 13.1 S ATPase that contained the beta-heavy chain and ICs 3-5. The polypeptide compositions of the complexes provide new information on the intermolecular associations that occur within dynein. Substructural features of the trout dynein polypeptides also were
Harvest cowpea plants about 2 weeks after inoculation, then homogenize at 4°C in two volumes of 0.5 M citrate buffer (pH 7.0) containing 0.1% thioglycollic acid. Express juice through cheesecloth, and add 20 ml carbon tetrachloride to every 100 ml extract. Shake the extract for 15 min, and clarify by low-speed centrifugation. Concentrate the virus by three cycles of differential centrifugation. Resuspend the pellets from high speed centrifugation in 0.01 M citrate buffer. Purify further by sucrose density-gradient centrifugation (Tsuchizaki et al., 1971).. ...
Exosomes purification and analyses comprise a fast evolving research area; more than 70% of published research on exosomes has been done within the last six years. Challenges to researchers working with exosomes include setting up density gradients by hand, because it is tedious, time-consuming and subject to user, lab, and method variability.
Previous studies in this laboratory have allowed the formulation of a model for the molecular arrangement of C5, C6, C7, C8, and C9 on the surface of cells undergoing immune cytolysis with an assigned cumulative m.w. of 995,000. To verify directly the existence of a C5-C9 complex, serum samples containing radiolabeled terminal components were activated at 37°C with EA, antigen-antibody complexes, CVF, inulin or zymosan. Subsequent sucrose density gradient ultracentrifugation showed that all treatments cited led to the formation, in varying degrees, of rapidly sedimenting material which incorporated C5, C6, C7, C8, and C9, but not C3. The reaction was inhibited by 0.01 M EDTA and 0°C. The complex had a sedimentation coefficient of 22.4S, a diffusion coefficient of 1.98 × 10-7 cm2 sec-1 and thus a calculated m.w. of 1.04 × 106.. ...
Purification of mitochondria and mitochondrial subfractionation. Mitochondria were purified from brain tissue using the discontinuous sucrose gradient method. Briefly, brain homogenate was made in ice-cold homo-buffer (0.32 M sucrose, 20 mM Tris-HCl, pH 7.4) and spun at 900 g, 4°C, for 10 minutes. The supernatant was transferred to another clean tube and spun at 10,000 g, 4°C, for 10 minutes. The resultant pellet, enriched for mitochondria, was resuspended in 2 ml homo-buffer, loaded on top of a sucrose gradient (1.2 M, 0.8 M, and 0.32 M sucrose; 20 mM Tris-HCl, pH 7.4) and spun at 53,000 g, 4°C, for 2 hours. The white band at the interface between medium (0.8 M) and heavy (1.2 M) solutions was collected as highly purified mitochondria. Mitochondria from cultured cells were isolated using a kit (catalog no. 89874) from Pierce. Mitochondrial subfractionation was carried out as described by Hovius et al. (40). Briefly, purified mitochondria (1 mg) were resuspended in 500 μl ice-cold buffer (10 ...
Cells. The Raji control cell line and the cell lines expressing either DC-SIGN (Raji-DC-SIGN) or L-SIGN (Raji-L-SIGN) were cultured as previously described (4). PBMCs were isolated from buffy coats by standard Ficoll-Hypaque density centrifugation, activated with phytohemagglutinin (3 μg/ml), and cultured in RPMI medium containing 10% FCS, penicillin (100 units/ml), and streptomycin (100 units/ml). On day 3 the cells underwent CD4+ enrichment by incubation with CD8 immunomagnetic beads (Dynal Biotech) and were negatively selected according to the manufacturers instructions and cultured with IL-2 (100 U/ml). DCs for the single-cycle transmission assay were generated from fresh PBMCs with cells layered on a standard Percoll gradient (Amersham Pharmacia). The light fraction with predominantly monocytes was collected, washed, and seeded in 24-well or 6-well culture plates at a density of 5 × 105 cells or 2.5 × 106 per well, respectively. After 60 minutes at 37°C, the adherent cells were ...
Cells. The Raji control cell line and the cell lines expressing either DC-SIGN (Raji-DC-SIGN) or L-SIGN (Raji-L-SIGN) were cultured as previously described (4). PBMCs were isolated from buffy coats by standard Ficoll-Hypaque density centrifugation, activated with phytohemagglutinin (3 μg/ml), and cultured in RPMI medium containing 10% FCS, penicillin (100 units/ml), and streptomycin (100 units/ml). On day 3 the cells underwent CD4+ enrichment by incubation with CD8 immunomagnetic beads (Dynal Biotech) and were negatively selected according to the manufacturers instructions and cultured with IL-2 (100 U/ml). DCs for the single-cycle transmission assay were generated from fresh PBMCs with cells layered on a standard Percoll gradient (Amersham Pharmacia). The light fraction with predominantly monocytes was collected, washed, and seeded in 24-well or 6-well culture plates at a density of 5 × 105 cells or 2.5 × 106 per well, respectively. After 60 minutes at 37°C, the adherent cells were ...
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Molecular Cloning, also known as Maniatis, has served as the foundation of technical expertise in labs worldwide for 30 years. No other manual has been so popular, or so influential.
Centrifugation is the use of the centrifugal forces generated in a spinning rotor to separate biological particles, such as cells, viruses, sub‐cellular organelles, macromolecules (principally proteins and nucleic acids) and macromolecular complexes (such as ribonucleoproteins and lipoproteins)
The growth of a mouse leukemia virus in an established mouse cell line was examined after the line became contaminated with an unidentified Mycoplasma species. The contaminated cultures grew well in small plastic cultures dishes, but they could not be propagated in larger roller bottles unless the growth medium was changed frequently. Cells from Mycoplasma-contaminated and Mycoplasma-free cultures were exposed to 3H-labeled uridine for 24 hr. Culture fluids were harvested 2 or 24 hr after labeling and purified by centrifugation through discontinuous sucrose gradients. Considerably less uridine-3H-labeled virus was recovered from supernatant fluids of Mycoplasma-contaminated cultures than from Mycoplasma-free cultures. Equilibrium sedimentation in sucrose gradients of uridine-3H-labeled material from culture supernatants of contaminated cultures produced 3H peaks at buoyant densities of 1.20 to 1.24 and 1.16 to 1.18 g/ml. Virus titers in culture fluids from Mycoplasma-contaminated cultures were ...
The present invention generally encompasses the control of the release rate of agents from a polymeric matrix. This control over the release rate of agents provides for control over, inter alia, the therapeutic, prophylactic, diagnostic, and ameliorative effects that are realized by a patient in need of such treatment. In addition, the control of the release rate of agents also has an effect upon the mechanical integrity of the polymeric matrix, as well as a relationship to a subjects absorption rate of the absorbable polymers.
... / insoluble fractions separated by differential centrifugation. FKIPS DCARD stable
Plasma membrane(PM) protein accounts for a small fraction of total cellular protein in plants but performs a very critical role in plant physiology. Isolation and purification of PM protein from plant tissues have been traditionally done by sucrose density ultracentrifugation and aqueous two-phase partitioning. These methods, while relatively effective, require ultracentrifugation and large amount of starting material. The procedures are usually tedious and time consuming.To overcome the shortcomings, we have developed this PM isolation kit. Plant tissues are first sensitized by buffer A, homogenized, and pass through a specialized filter cartridge that allows homogenates to pass through with a zigzag path. The cell membranes are ruptured into a range of predefined size during the process. Native plasma membranes are separated from a mixture of un-ruptured cells, nuclei, cytosol and organelles by subsequent differential centrifugation and density centrifugation without using ...
I am having trouble isolating mtDNA using CsCl gradients. Is there an easier way to isolate mtDNA? I was wondering if anyone could give me some help! This is becoming a really big problem!!!!! Thank oyu very much, Rodney Earl Pettway Rodney Earl Pettway Department of Plant Pathology and Microbiology Texas A&M University College Station, TX 77843 Pettway at ppserver.tamu.edu ...
Density marker beads are small colored microspheres of known density that are used for calibrating density gradients and determining density in gradient columns
JML-135-2007-105-114. This paper contains the results of a new experimental study of the effect of temperature on density, refractive index on mixing and ultrasonic velocity for a number of linear n-alkanes conbined with ethanol. A perusal of deviations between the experimental and calculated derived magnitudes shows that the predictive procedures give a qualitative estimation for the studied mixtures due to their high nonideality.. ...
2014.1-2015.12 Academy of Mathematics & Systems Science Postdoc within the research center NCMIS, working with Prof. Ping Zhang on density patch problem ...
View Notes - ps_2 from CHEMICAL E 20.410j at MIT. DOWNSTREAM PROCESSING Problem Set #2 Problem 1 A key to understanding centrifugation is understanding the equations that describe it. One can
The classical procedure for estimating the approximate size of a protein is by its sedimentation coefficient, determined either using an analytical ultr...
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The distribution of [3H]leukotriene D4 [( 3H]LTD4) receptors in subcellular membrane fractions obtained from sheep tracheal smooth muscle was studied. Using differential centrifugation and discontinuous sucrose density gradient centrifugation, the subcellular membranes were separated into six fractions. The [3H]LTD4 receptor distribution profile in these fractions correlated with markers for the plasma membrane (5-nucleotidase and alkaline phosphodiesterase) and did not correlate with markers for the mitochondria (cytochrome c oxidase and succinate-dependent cytochrome c reductase). The dissociation constant (Kd) and maximum number of binding sites (Bmax) for [3H]LTD4 binding to the receptors in the crude mixture of membranes (PII) were 0.38 +/- 0.2 nM and 77 +/- 14 fmol/mg of protein, respectively. The Kd and Bmax of [3H]LTD4 binding to the receptors in the plasma membrane-enriched fraction (FII) were 0.40 +/- 0.2 nM and 268 +/- 46 fmol/mg of protein, respectively. The specificity profile of ...
Hypertriglyceridemia concurrent Hyperlipidemia: Vertical Density Gradient Ultracentrifugation a Better Test to Prevent Undertreatment of High-Risk Cardiac Patients Curator: Aviva Lev-Ari, PhD, RN Equation May Give Wrong LDL Status By Todd Neale, Senior Staff Writer, MedPage Today Published: March 28, 2013 Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo,…
Lee J.C., Henry B., Yeh Y.C.. Specific binding of purified proteins from the large ribosomal subunits of Saccharomyces cerevisiae to 5.8 S rRNA was examined by three different methods: nitrocellulose membrane filtration, sucrose density gradient centrifugation, and RNA-Sepharose column chromatography. RNA-protein complex formation was proportional to the amount of proteins added to the reaction mixture. The binding of proteins to the RNA could be saturated. Such RNA-protein complexes were isolated on sucrose density gradients. Protein species present in these complexes were isolated, iodinated, and analyzed by two-dimensional polyacrylamide gel electrophoresis. Eleven proteins, L13, L14, L17, L19, L21, L24, L25, L29, L30, L33, and L39, were identified. By comparison, only six proteins interacted with the 5.8 S rRNA-Sepharose under similar ionic conditions. They were proteins L14, L21, L24, L27, L29, and L30. To better characterize these binding proteins, the interaction of individual proteins ...
After ethics committee approval (ethics committee of the University Hospital Essen, Essen, Germany) and written informed consent, venous blood (24 ml) was withdrawn from 10 healthy individuals with the homozygous insertion (II) or deletion (DD) genotype, respectively, and centrifuged at 1800g for 20 min using Ficoll density gradient centrifugation tubes (Vacutainer CPT tubes; Becton Dickinson, Franklin Lakes, NJ). Monocytes were resuspended in RPMI 1640 medium (Gibco Products Invitrogen Corporation, Grand Island, NY) containing 5% fetal calf serum (Biochrom AG, Berlin, Germany) and antibiotics (100 U/ml penicillin and 100 μg/ml streptomycin; Invitrogen Corporation, Carlsbad, CA). The cell suspension was added to cell culture tubes, and monocytes were allowed to adhere to the surface of the tubes for 2 h. Finally, the supernatant was discarded, fresh RPMI 1640 medium was added, and the cells were allowed to rest for 48 h (37°C; 5% CO2in air) before the experiments. Meanwhile, 12 mm glass plates ...
Rationale: We previously identified circulating mesoangioblasts (cMABs), a subset of mesenchymal stem cells that co-express KDR and Nkx2.5, from the patients undergoing open heart surgery. cMABs are capable of differentiating into endothelial cells, smooth muscle cells and cardiomyocytes. More recently, we demonstrated that hepatocyte growth factor (HGF) induces cMAB mobilization in rodents.. Objective: We therefore hypothesized that heparin induces cMAB mobilization by increasing the serum levels of HGF. We also explored the niche of cMABs.. Methods and Results: Patients undergoing cardiac catheterization were treated with an increasing dose of heparin at 100U/kg (n=7), 200 U/kg (n=11) and 300 U/kg (n=11). Serum HGF levels were determined by ELISA. Mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation and cultured on a fibronectin-coated dish, and the number of outgrowing colonies was counted. Consistent with previous studies, heparin ...
F3088-14 Standard Test Method for Use of a Centrifugation Method to Quantify/Study Cell-Material Adhesive Interactions cell adhesion~ cell-to-material interaction~
TY - JOUR. T1 - Fractions of HeLa DNA differing in their content of guanine + cytosine. AU - Schildkraut, Carl L.. AU - Maio, Joseph J.. PY - 1969/12/14. Y1 - 1969/12/14. N2 - DNA isolated from preparations of HeLa cell nucleoli has been fractionated into six components which band in CsCl at densities corresponding to their G + C contents according to the relation: ρ{variant} = 0.98 (G + C) + 1.659, where ρ{variant} refers to buoyant density and (G + C) to the average mole fraction of guanine + cytosine. This nucleolar DNA is significantly enriched with respect to two satellite bands: a light satellite (ρ{variant} = 1.686 g/ml.) and a heavy satellite (ρ{variant} = 1.712 g/ml.). In an alkaline CsCl density gradient, the light satellite DNA can be separated into two complementary strands, as demonstrated by base composition analysis.. AB - DNA isolated from preparations of HeLa cell nucleoli has been fractionated into six components which band in CsCl at densities corresponding to their G + C ...
Define Buoyant density. Buoyant density synonyms, Buoyant density pronunciation, Buoyant density translation, English dictionary definition of Buoyant density. n. 1. a. The tendency or capacity to remain afloat in a liquid or rise in air or gas. b. The upward force that a fluid exerts on an object less dense than...
The following enzyme-assisted method is useful (Takanami & Kubo, 1979a). Powder frozen leaves of infected P. floridana, and disrupt in a mechanical blender in 0.1 M sodium citrate buffer (2 ml/g leaf), pH 6.0, containing 1% Driselase (an enzyme preparation which macerates plant tissue), and 0.1% thioglycollic acid. Shake the suspension for 2 h at 25 to 28°C and then emulsify by adding 0.5 vol. of a 1:1 (v/v) mixture of chloroform and n-butanol, and centrifuge at low speed. Precipitate the virus from the aqueous phase by adding polyethylene glycol (M. Wt 6000) to 8% (w/v) and NaCl to 0.4 M. Resuspend the virus in 0.01 M borate buffer, pH 8.0, concentrate by two cycles of differential centrifugation using 0.0l M phosphate buffer, pH 7.6 to 8.0, as the resuspending medium. Further purification is achieved by sucrose density gradient centrifugation. Virus yields are 5 to 10 mg per kg leaf material, at least ten times more than those obtained by methods that do not include the use of ...
Cell culture: monocultures. Primary human fetal astrocyte cultures were established from 3 different brains as previously described (67). We confirmed an identical in vitro phenotype of commercially available cells (Lonza) and cross-referenced these to previous phenotypes. To establish human CD3+ T lymphocyte cultures from human blood of healthy donors, density centrifugation using Ficoll-Paque PLUS (GE Healthcare) was initially performed to isolate peripheral blood mononuclear cells (PBMCs) from whole blood. Six milliliters of whole blood containing acid citrate dextrose anticoagulant (Biological Specialty Corp.) was diluted with an equal volume of HBSS (Mediatech Inc.) and carefully layered in 15-ml tubes prefilled with 4 ml of density gradient medium. Tubes were centrifuged 40 minutes at 900 relative centrifugal force (RCF). PBMCs were collected by transfer pipette and afterward washed 2-3 times in HBSS (Mediatech Inc.) and centrifuged 15 minutes at 250 RCF. Human CD3+ T lymphocytes were then ...
To this mixture, 3mL absolute ethanol (EtOH, 99.99%) and sodium hydroxide (NaOH, 1M) mixture (in equal volume) were added and subjected to microwave assisted pyrolysis for 5min till color of the mixture turned to wine red. This mixture was separated by sucrose density gradient centrifugation (SDGC) using 50-100% gradient concentration of sucrose. Three distinct bands were removed carefully and their properties were studied. Bands are referred to B1, B2, and B3 for further discussions. Each fraction was subjected to repeated centrifugation steps to get rid of residual sucrose and pure C-dots were Inhibitors,research,lifescience,medical collected by spinning at 8385×g for 15min. On vacuum heating. for 8h, powdered form of black colored C-dots was obtained which was then used to make 100mg/mL stock solution and stored at −20°C. 2.4. Synthesis of [email protected] Conjugate For the synthesis of the above conjugate, 0.5mL (1000μM) ciprofloxacin solution was added to 9.5mL (95mg/mL) C-dots and ...
SW 41 Ti Rotor Assembly; For use in instruments classified: HRS Major Applications: Rate-zonal and isopycnic centrifugation of viruses, rate-zonal centrifugation of RNA. Includes: Part No. Description SW 41 Ti Rotor 333790; Bucket ...
The concentrated viral lysate is purified via sucrose density gradient centrifugation, providing a semi-purified antigen of |60% viral protein...
Day, E D.; Mickey, D D.; Rigsbee, L C.; and Meier, H, "Zonal centrifugation and flotation-fractionation of msd mutant mouse brain." (1972). Subject Strain Bibliography 1972. 1757 ...
Ive been doing the liquid ionic cesium chloride protocol for 4 months. This one calls for 3 grams a day of the cesium, along with about half that much daily potassium. I also wondered about the rate of response compared to what I read online, but then realized most of what I read referenced a dose of 6 or 9 grams daily, meant to be taken for a .... [Chat Online] ...
High pH Therapy is based on the ready uptake of cesium chloride by cancer cells, and is aimed at depriving the cell of glucose while supporting the body with antioxidants and other nutrients.
Enveloped virus-like particles (VLPs) are increasingly used as vaccines and immunotherapeutics. Frequently, very time consuming density gradient centrifugation
It has been suggested that GAP-43 (growth-associated protein) binds to various proteins in growing neurons as part of its mechanism of action. To test this hypothesis in vivo, differentiated N1E-115 neuroblastoma cells were labeled with [35S]-amino acids and were treated with a cleavable crosslinking reagent. The cells were lysed in detergent and the lysates were centrifuged at 100,000 x g to isolate crosslinked complexes. Following cleavage of the crosslinks and analysis by two-dimensional gel electrophoresis, it was found that the crosslinker increased the level of various proteins, and particularly actin, in this pellet fraction. However, GAP-43 was not present, suggesting that GAP-43 was not extensively crosslinked to proteins of the cytoskeleton and membrane skeleton and did not sediment with them. GAP-43 also did not sediment with the membrane skeleton following nonionic detergent lysis. Calmodulin, but not actin or other proposed interaction partners, co-immunoprecipitated with GAP-43 from the
DNA - Deoxyribonucleic Acid and RNA - Ribonucleic Acid: Biology Assignment Help, Homework Help, Project Help and Instant solution for DNA-RNA with qualified biology experts.
Use this EasySep™ kit to isolate untouched neutrophils from human whole blood without density gradient centrifugation, sedimentation, or RBC lysis.
Direct isolation of untouched immune cells from whole blood, buffy coat, or LRSC in just 25 minutes. Get pure target cells from large volumes without the need for density gradient centrifugation or RBC lysis. - Ísland
Direct isolation of untouched immune cells from whole blood, buffy coat, or LRSC in just 25 minutes. Get pure target cells from large volumes without the need for density gradient centrifugation or RBC lysis. - USA
In seismic processing, one goal is to recover missing traces when the data is sparsely and incompletely sampled. We present a method which treats this reconstruction problem from a novel perspective. By utilizing its connection with the general matrix completion (MC) problem, we build an approximately low-rank matrix, which can be reconstructed through solving a proper nuclear norm minimization problem. Two efficient algorithms, accelerated proximal gradient method (APG) and low-rank matrix fitting (LMaFit) are discussed in this paper. The seismic data can then be recovered by the conversion of the completed matrix into the original signal space. Numerical experiments show the efficiency and high performance of data recovery for our model compared with other models.
Minimize double Time=10; Time_Stop Criteria(1,Time,clock()); //Terminates after Time second, first argument signifies number of cores running // Minimizes the function, with stepsizes based on Lipchitz constants with //Random starting point, Full Gradient method Min1.Optimize("Lipschitz",&Criteria,"Random"); cout ,, Min1.Get_Min().transpose() ,, endl; Error_Stop Criteria2(0,0.1); // First argument corresponds to Func. Min, and second to desired error // Minimizes the function, with stepsizes based on Lipchitz constants with Random starting point, PCDM with number of cores=2 Min3.Optimize(2,"Lipschitz",&Criteria2,"Random"); cout ,, Min3.Get_Min().transpose() ,, endl; ...
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No. However, a second centrifugation step helps remove traces of buffy coat that may be accidentally transferred when aspirating plasma after the first centrifugation step. ...
In 1944, Oswald Avery, Colin MacLeod, and Maclyn McCarty published an article in which they concluded that genes, or molecules that dictate how organisms develop, are made of deoxyribonucleic acid, or DNA. The article is ...
Results for sedimentation tank equipment from 2H, 2H TUBEdek, A.YITE and other leading brands. Compare and contact a supplier near you
상세정보: D-(+)-Sucrose. 당사는 제품 선택, 서비스, 공정 우수성을 통해 과학을 지원하며 고객이 과학의 가능성을 확장하도록 돕습니다.
Abstract In October-November, 1988 there was an outbreak of dengue fever in the Kaoshiung area of southern Taiwan. We collected 100 serum samples from 96 patients at the onset of their fever for virus cultures and identification. A human promonocyte cell line (HL-CZ) established in our laboratory was used and proved to be susceptible for dengue virus propagation. Type 1 dengue virus in the HL-CZ cell culture was identified by immunofluorescence tests using monoclonal antibodies, and also by hemagglutination tests with goose red blood cells. The density of the virus particles, as measured by sucrose gradient ultracentrifugation, ranged from 1.186 to 1.224 g/ml. The virus yield from this cell culture is comparable with that from the C6/36 mosquito cell line. There was a significant correlation between the antibody responses tested with Western dot blots and hemagglutination inhibition techniques.
Developmental and global regulation of mRNA translation plays a major role in regulating gene expression in mammalian spermatogenic cells. Sucrose gradients are widely used to analyze mRNA translation. Unfortunately, the information from sucrose gradient experiments is often compromised by the absence of quantification and absorbance tracings, and confusion about the basic properties of sucrose gradients. The Additional Materials contain detailed protocols for the preparation and analysis of sucrose and Nycodenz gradients, obtaining absorbance tracings of sucrose gradients, aligning tracings and fractions, and extraction of equal proportions of RNA from all fractions. The techniques described here have produced consistent measurements despite changes in personnel and minor variations in RNA extraction, gradient analysis, and mRNA quantification, and describes for the first time potential problems in using gradients to analyze mRNA translation in purified spermatogenic cells. Accurate quantification of
A discontinuous sucrose density gradient was used to separate membrane fractions from a homogenate of maize root tips. Endoplasmic reticulum-, Golgi apparatus-, plasma membrane- and mitochondria-rich fractions were identified by their enzymic characteristics and by their appearance under the electron microscope. Maize roots were incubated in vivo with D-[U-14C]glucose, [Me-14C]choline chloride and diazotized [U-3H]sulphanilic acid. The pattern of incorporation of radioactivity into the various membrane fractions was investigated. Analyses of the polypeptide chains of the membrane fractions by SDS-polyacrylamide gel electrophoresis showed that the mitochondria-rich fraction had a different pattern of polypeptides from that of the other membrane fractions. The results are discussed in relation to the hypothesis of endomembrane flow and differentiation. ...
Summary We examined the properties of the mouse serum lipoprotein responsible for specific neutralization of the endogenous mouse xenotropic (X-tropic) type C retrovirus. The anti-X-tropic virus activity of the mouse lipoprotein neutralizing factor (NF) could not be blocked by sugars or lectins. Moreover, neutralization did not involve rupture of the virion core. Sucrose density gradient analysis of X-tropic virus mixed with various lipoprotein preparations demonstrated that the binding of complete virions to NF is associated with the neutralization.
The tRNA content and aminoacyl-tRNA synthetases of regenerating liver in the phase of rapid growth were compared with those of livers from both intact and sham-operated rats. At 48 h after hepatectomy, the amount of active tRNA (called total acceptor capacity) is significantly higher in regenerating liver than in control livers, owing to a general, possibly not uniform, increase in the various tRNA families, which suggests that it may contribute to the increased protein synthesis and to decreased protein degradation as well. The activities of most, but not of all, aminoacyl-tRNA synthetases in cell sap of regenerating liver tend to be greater than normal. Increased activity of histidyl-tRNA synthetase fits in with the possibility that the mechanisms that control the rate of protein degradation through aminoacylation of tRNAHis in cultured cells [Scornik (1983) J. Biol. Chem. 258, 882-886] also operate in the liver and play a role in regeneration. Sedimentation analysis of cell sap in sucrose ...
Semi-conservative replication of DNA was proved by the work of Mathew Meselson and Franklin Stahl (1958). They grew Escherichia coli for many generations in a medium having heavy isotope of nitrogen, in the form of 15NH4Cl, till the bacterial DNA became com-pletely labelled with heavy isotope.. The labelled bacteria were then shifted to fresh medium hav-ing normal or 14N nitrogen. Samples were taken for each generation (one generation takes 20 minutes as E. coli divides in 20 minutes) and the DNA was tested for the heavy isotope of nitrogen through density gradient centrifugation using caesium chloride. Caesium chloride is highly water soluble heavy salt.. When spun in centrifuge at high speed (say 50,000 revolutions per minute) the salt forms a density gradient with heaviest most concentrated region at the bottom and successively less concentrated lighter one towards the surface. When DNA is mixed with caesium chloride it will settle down at a particular height in centrifugation, heavier ...
Cesium chloride, 99+%, for analysis, ACROS Organics™ 250g; Plastic bottle Cesium chloride, 99+%, for analysis, ACROS Organics™ Cesium
Cesium chloride, White powder/crystalline/beads, 99.99% (Metals basis), Alfa Aesar™ 50g Cesium chloride, White powder/crystalline/beads, 99.99% (Metals basis),...
Our understanding of the structure of the plasma membrane of mammalian cells was based on the Singer-Nicolson fluid mosaic membrane model, where all the constituents of the membrane move freely ( Singer and Nicolson, 1972). In recent years the Singer-Nicolson membrane model has been changed by demonstrations of lateral heterogeneities, patches and domains in the plasma membrane ( Edidin, 1996; Jacobson et al., 1995; Kusumi and Sako, 1996). These lateral heterogeneities of the plasma membrane, often called `lipid rafts, are emerging as sites of cellular signalling.. In this study we decided to investigate the significance of raft formation in LPS-mediated cellular activation. Using biochemical techniques in order to isolate lipid rafts on the basis of their insolubility in Triton X-100 and low buoyant density centrifugation, we isolated lipid rafts before and after LPS stimulation. Certain molecules involved in the innate recognition of bacteria, such as CD14 and hsp70 and 90, were ...
Looking for Centrifugation, isopycnic? Find out information about Centrifugation, isopycnic. A line on a chart connecting all points of equal or constant density. Of equal or constant density, with respect to either space or time Explanation of Centrifugation, isopycnic
Human large bowel lamina propria lymphoid cells have been isolated using both mechanical and enzymatic techniques. Their separation from other cell types after isolation was effected with greater efficiency by sedimentation on isokinetic gradients than by filtration through glass bead columns. After being purified, the capacity of the lamina propria lymphocytes to function in vitro as effector cells in antibody-dependent cellular cytotoxicity was determined. Mechanical distruption of the mucosa gave low yields of lymphoid cells, which lacked the capacity for cytotoxicity. Enzymatic digestion of mucosal tissue, by comparison, yielded large numbers of viable lymphoid cells which retained a significant level of cytotoxic activity. Investigation revealed that mechanical homogenisation stimulated the synthesis of prostaglandin E2, and inhibitor studies showed that this mediator was responsible for the lack of cytotoxic activity in mechanically-liberated lymphocytes.. ...
TY - JOUR. T1 - Proliferation and cell loss of human leukemic cell subpopulations in liquid culture. AU - Bernabei, P. A.. AU - Agostino, F. C.. AU - Bezzini, R.. AU - Saccardi, R.. AU - Gattei, V.. AU - Santini, V.. AU - Casini, M.. AU - Rossi Ferrini, P.. PY - 1988/3. Y1 - 1988/3. N2 - A kinetic study was performed on leukemic blasts from patients with acute myeloid leukemia, separated into 2 subpopulations by a specific density gradient. The growth curve and the [3H]-thymidine uptake were simultaneously analyzed. While cumulative nucleotide uptake fitted with the growth kinetics in the low-density fraction, such a concordance was not found in the high-density subpopulation. That indicated the occurrence of simultaneous growth and loss in the high density fraction, which could not be evaluated by a simple numerical determination.. AB - A kinetic study was performed on leukemic blasts from patients with acute myeloid leukemia, separated into 2 subpopulations by a specific density gradient. The ...
Isolation of the PSD fraction. PSD fractions were prepared from rat forebrains as previously described (Carlin et al., 1980; Cho et al., 1992). Synaptosomes were isolated from homogenates by differential and density gradient centrifugation and then extracted with 0.5% Triton X-100 for 15 min. The resulting "One-Triton" PSD fraction was pelleted by centrifugation at 36,800 × gfor 45 min. A portion of the One-Triton fraction was extracted again either with 0.5% Triton X-100 for 15 min or with 3%N-lauroyl-sarcosine for 10 min and then pelleted by centrifugation at 201,800 × g for 1 hr to obtain the "Two-Triton" PSD fraction or the "One-Triton plus Sarcosyl" PSD fraction, respectively. Protein concentrations were determined by a modified method of Lowrey (Peterson, 1983).. Identification of proteins in the PSD fraction by mass spectrometry. Protein identification was performed by mass spectrometry combined with sequence database searches (Jensen et al., 1998). Protein bands cut from a Coomassie ...
Software Packages for Holonomic Gradient Method. The numerical evaluation of the normalizing constant for a given statistical distribution is a fundamental problem in statistics. For example, the normalizing constant of the Gaussian distribution is expressed in terms of a rational expression of a parameter of the distribution named as the standard deviation. However, normalizing constants of many interesting stasistical distributions do not have such closed expressions. The holonomic gradient method, HGM in short, is a general method to evaluate normalizing constant numerically for several parameters in the framework of Zeilbergers holonomic systems approach. In fact, broad classes of normalizing constants are holonomic functions with respect to parameters. Then, such normalizing constants satisfy holonomic systems of linear partial differential equations. The HGM consists of three steps for a given normalizing constant. (1) Find a holonomic system satisfied by the normalizing constant. We may use
The regional metabolism of high-molecular-weight RNA in the developing female rat brain was investigated after the intracranial injection of [32P]P1. The synthesis of polyadenylated RNA relative to high-molecular-weight RNA was determined after oligo(dT)-cellulose chromatography of total cellular high-molecular-weight RNA labelled after 4h. In both hypothalamus and cortex this synthesis was significantly higher during the first 10 days post partum than at subsequent ages. In both regions apparently more mRNA is synthesized in the young. The ratio of the specific radioactivity of cytoplasmic high-molecular-weight RNA relative to that of the nucleus, measured after a 48 h period of labelling, was considered to be an index of the nucleocytoplasmic transport of newly synthesized RNA [Berthold & Lim (1976) Biochem. J. 154, 529-539]. In the cortex, nucleo-cytoplasmic RNA transport in rats aged up to 20 days was significantly higher than in older rats, with the maximal value being attained between 16 ...
Hi Peter Which cell type do you wish to stain? Neurons or glia? Julia >I am looking for an antibody against a plasma membrane >marker protein for > >IHC (brainstem slices). _______________________________________________ Histonet mailing list [email protected] http://lists.utsouthwestern.edu/mailman/listinfo/histonet ...
This method can decrease interference caused by the internal variables of the host, such as organism immunity level, allosteric effects of hemoglobin, and capability to metabolize drugs (Amaratunga et al., 2012; Witkowski et al., 2013a). RSA in vitro is proposed to give phenotypic information, thus enabling screening for reduced susceptibility to ART in prolonged clearance parasites (Witkowski et al., 2013b).. IMPROVED METHODS FOR RSA While feasible and efficient for the surveillance of ART resistance, the RSA tool has several limitations, including sophisticated Percoll gradient centrifugation, biased assessment of the degree of sorbitol synchronization treatment, and exacting requirements for counting viable parasites (Witkowski et al., 2013a). In Whitney A. Kites laboratory, two alternative RSA methods have been developed; that is, filtration ring-stage survival assay and sorbitol-only ring-stage survival assay. The first is essentially a filtration process in which the 0-3 h fresh ...
In forensic casework analysis, mitochondrial deoxyribonucleic acid (DNA) often is used when the evidence material contains scarce amounts of DNA. Here, a mitochondrial DNA typing system for D-loop and coding region analysis based on pyrosequencing is described. Pyrosequencing is a real-time, single-tube sequencing-by-synthesis method, in which a cascade of enzymatic reactions yields detectable light. This pyrosequencing system has a higher resolution than the D-loop analysis performed routinely today as it also covers informative positions in the mitochondrial coding region. The system is composed of 16 polymerase chain reaction (PCR) fragments and 24 pyrosequencing reactions with a turn around time for a 96-well plate of less than 3 h after PCR.. ...
In order to qualify as a biomarker of novel therapies, this imaging metric for measuring tumor volume must demonstrate a better correlation with therapy-induced biologic activity/clinical outcome than conventional methods. To evaluate volumetric techniques in assessing therapy response and gain acceptance of such techniques in clinical practice, computer assistance is necessary to perform measurements and reduce variability in measured values.. Computer-aided measurement of tumor volume requires automated separation of the tumor from its surrounding background through segmentation. The strategy chosen for segmentation of a specific type of tumor is often influenced by the growing pattern of the tumor and its relationship to surrounding anatomical structures. A simple thresholding algorithm involves an automated determination of a density value (or Hounsfield unit threshold) that separates the tumor from its background based on density distribution. A region-growing algorithm employs the ...
Here we present protocols for detergent-free homogenization of cultured mammalian cells based on nitrogen cavitation and subsequent...
The pH Therapy Basic Package 1 with Cesium Chloride and Potassium is designed to be used in conjunction with an alkalizing diet and lifestyle change.
The mixing zone between Cayuga Lake, N.Y. and one of its tributaries, Salmon Creek, was studied to determine effects of physical processes such as adsorption, precipitation or sedimentation on...
Carr, Dr Steven M. "CsCl density-gradient centrifugation". www.mun.ca. Retrieved 2017-04-03. Martinez, Lluis. "Magnetic DNA ... With high speed buoyant density ultracentrifugation, a density gradient is created with caesium chloride in water. DNA will go ... to the density that reflects its own, and ethidium bromide is then added to enhance the visuals the nucleic acid band provides ...
"Isolation of human NK cells by density gradient centrifugation". J. Immunol. Methods. 36 (3-4): 285-91. doi:10.1016/0022-1759( ... The demonstration that density gradient-isolated large granular lymphocytes were responsible for human NK activity, made by ... Using discontinuous density centrifugation, and later monoclonal antibodies, natural killing ability was mapped to the subset ...
"An analysis of eukaryotic genomes by density gradient centrifugation". Journal of Molecular Biology. 108 (1): 219-235. doi: ... The DNA fragments extracted by the gradient centrifugation were later termed "isochores", which was subsequently defined as " ... uncovered the compositional non-uniformity within vertebrate genomes using thermal melting and density gradient centrifugation ...
A density gradient medium for the centrifugation of biological particles. Historically Metrizamide replaced Pantopaque as the ...
OptiPrep™: The ideal density gradient medium, Axis-Shield Density Gradient Media. Accessed on line Nov. 19, 2015. Waite J.A, ... Post centrifugation the supernatant above and the cushion below is removed, leaving a concentrated sperm pellet in the conical ... It is sold under the trade name Visipaque; it is also sold as a density gradient medium under the name OptiPrep. Visipaque is ... 2008;70:704-714 http://www.cosmobiousa.com/axis-shield-density-gradient-optiprep.html http://www3.gehealthcare.com/en/products/ ...
Purification before culturing can be accomplished by CsCl density gradient centrifugation. Renaudin, J; Aullo, P; Vignault, JC ... SpV1 buoyant densities are 1.39 g/cm3 in CsCl and 1.21 g/cm3 in metrizamide. Spiroplasma phages affect members of the genus ...
Isolate the mRNA-ribosome complexes using sucrose gradient density centrifugation or specialized chromatography columns. Phenol ... These sites of slow or paused translation are demonstrated by an increase in ribosome density and these pauses can link ...
"Ribonucleic acids fractionation by density-gradient centrifugation and by agar gel electrophoresis: A comparison". Analytical ...
"Separation and concentration of living dinoflagellate resting cysts from marine sediments via density-gradient centrifugation ... Another method, rarely used, uses a sucrose gradient. Recent times have brought about the possibility to get molecular ... calibration as annual density proxy and first evidence of pseudo-cryptic speciation". Journal of Quaternary Science. 27: 734- ...
Ycf4 co-fractionates with a protein complex larger than PSI upon sucrose density gradient centrifugation of solubilised ...
Such an "equilibrium" centrifugation can allow extensive purification of a given particle. Sucrose gradient centrifugation - a ... Centrifugation is a process that uses centrifugal force to separate mixtures of particles of varying masses or densities ... However, when the proteins are moving through a sucrose gradient, they encounter liquid of increasing density and viscosity. A ... Samples separated by these gradients are referred to as "rate zonal" centrifugations. After separating the protein/particles, ...
... by density gradient centrifugation. The tube contains an insert that prevents the mixing of the density gradient medium and ... These immunorosettes pellet when centrifuged over a density gradient medium, leaving untouched target cells at the plasma: ... density gradient medium interface. SepMate is a tube that allows for the isolation of peripheral blood mononuclear cells (PBMC ...
... for density gradient centrifugation and for separating mixtures. Common applications of heavy liquids include: Density gradient ... A heavy liquid is a solution or liquid chemical substance with a high density and a relatively low viscosity. Heavy liquids are ... centrifugation Separating mixtures and sink/swim analysis Flotation process Determination of density The classical heavy ... With this relatively new heavy liquid densities up to 3.1 g·cm−3 can be adjusted . Adding parts of pulverulent Tungsten carbide ...
... or other substances on the basis of their density. Isopycnic centrifugation refers to a method wherein a density gradient is ... After this gradient is formed particles move within the gradient to the position having a density matching their own (this is ... Unless there is a flux of mass into or out of a control volume, a process which occurs at a constant density also occurs at a ... It may also be applied to other situations where a continuous medium has smoothly-varying density, such as in the case of an ...
... of nervous tissue under isotonic conditions and subsequent fractionation using differential and density gradient centrifugation ... Synaptosomes may be used to isolate postsynaptic densities or the presynaptic active zone with attached synaptic vesicles. ... or postsynaptic densities can now be studied by proteomic techniques, leading to a deeper understanding of the molecular ... enrichment of different types of postsynaptic densities". J Cell Biol. 86: 831-845. doi:10.1083/jcb.86.3.831. CS1 maint: ...
These studies utilized the method of density gradient centrifugation that was developed for the test of the semiconservative ...
These nuclei can then be removed using cytochalasin B to disrupt the cytoskeleton and centrifugation in a density gradient to ...
... and density gradient centrifugation. It has significant advantages when compared to the use of zinc chloride solution or the ... density 3.1 g/cm3) SPT is widely used as a heavy liquid for gravity separation (sink swim analysis) ...
... "density-gradient") centrifugation. It is isostructural with potassium salt. Coordination sphere of one of two types of Cs+ site ...
... and allowed them to be isolated as sealed structures by the combination of differential and density gradient centrifugation. He ... shock he subsequently showed that intact synaptic vesicles of high purity can be isolated by density gradient centrifugation ... an electron-microscopic study of cell fragments derived by homogenization and centrifugation". J Anat. 96 (Pt. 1): 79-88. PMC ...
... and TEM-8 in colorectal carcinoma patients using OncoQuick density gradient centrifugation system". J. Surg. Res. 155 (2): 183- ... 2007). "Relationship between vascular invasion and microvessel density and micrometastasis". World J. Gastroenterol. 13 (46): ...
... coli through sucrose-density-gradient centrifugation. Cell-free synthetic pathway biotransformation biosystems are proposed as ... "A high-energy-density sugar biobattery based on a synthetic enzymatic pathway". Nature Communications. 5: 3026. doi:10.1038/ ... reticulocytes have been lysed in a solution of MgCl2 and had the extract filtered away from the membranes by centrifugation. ...
Density gradient centrifugation (in a continuous or discontinuous gradient) can concentrate semen samples with low ... sorting have been routinely used in assisted reproductive technologies including the method of density gradient centrifugation ... Similarly, so-called swim-up techniques apply a centrifugation step and then sperm is allowed to swim up into a medium, thus ... However, use of sperm centrifugation is detrimental to the sperm viability and elicits production of reactive oxygen species. ...
... anticoagulated blood sample that contains most of the white blood cells and platelets following density gradient centrifugation ... After centrifugation, one can distinguish a layer of clear fluid (the plasma), a layer of red fluid containing most of the red ...
... to select sperm from semen by density gradient centrifugation, for use in techniques such as in vitro fertilization or ... It is used for the isolation of cells, organelles, and/or viruses by density centrifugation. Percoll consists of colloidal ... Pertoft, H.; Laurent, T.C.; Laas, T.; Kagedal, L. (1978). "Density gradients prepared from colloidal silica particles coated by ... Percoll is well suited for density gradient experiments because it possesses a low viscosity compared to alternatives, a low ...
Density Gradient CentrifugationEdit. Density gradient centrifugation is considered one of the more efficient methods of ... Density gradient centrifugation can be used both as a separation technique and as a method of measuring the densities of ... which in fact have little to no density gradient.[7]. Differential CentrifugationEdit. Differential Centrifugation is a type of ... They used density gradient centrifugation to determine which isotope or isotopes of nitrogen were present in the DNA after ...
The aim of the study was to compare the new density gradient centrifugation system OncoQuick with the standard density gradient ... centrifugation system Ficoll for improved tumor cell enrichment in... ... Density gradient centrifugation with OncoQuick results in higher relative tumor cell enrichment than Ficoll density gradient ... The aim of the study was to compare the new density gradient centrifugation system OncoQuick with the standard density gradient ...
Alternatively, density gradient centrifugation may be performed using multiple layers of the different gradient densities. This ... on the accuracy of the density gradients, i.e., the density gradients must be prepared such that their densities are accurate ... Density gradient centrifugation is a method of separating cells based on the different densities of cell types in a mixture. ... Thus, density gradient centrifugation is most often carried out through repetitive steps based on a series of different density ...
DNA Extraction from 0.22 μM Sterivex Filters and Cesium Chloride Density Gradient Centrifugation, Protocol for Isolation of ... Characterization and Isolation of Mouse Primary Microglia by Density Gradient Centrifugation, ... Isolation of Human Monocytes by Double Gradient Centrifugation and Their Differentiation to Macrophages in Teflon-coated Cell ... Preparation of Synaptic Plasma Membrane and Postsynaptic Density Proteins Using a Discontinuous Sucrose Gradient, Human ...
Density-Gradient Separation of Organic and Inorganic Particles by Centrifugation Message Subject. (Your Name) has forwarded a ... Aqueous suspensions of particulate organic and inorganic material were centrifuged in a 2-bromo-ethanol density gradient. The ... degree of separation with this new technique is superior to that achieved with sucrose density gradients. ...
What is density-gradient centrifugation? Meaning of density-gradient centrifugation medical term. What does density-gradient ... Looking for online definition of density-gradient centrifugation in the Medical Dictionary? density-gradient centrifugation ... density-gradient centrifugation. density-gradient centrifugation. the separation of the components of an homogenate by a ... and Percoll density-gradient centrifugation [13, 25].. Percoll density-gradient centrifugation method could be used to assess ...
Zone-spreading of a major component by non-ideal sedimentation in density-gradient centrifugation can cause zone spreading of a ... but in a much wider zone after centrifugation with a large amount of a second virus. ... A small amount of southern bean mosaic virus was contained in a narrow zone after density-gradient centrifugation, ... A small amount of southern bean mosaic virus was contained in a narrow zone after density-gradient centrifugation, but in a ...
... subjecting the blood of the mother body to first density-gradient centrifugation to collect a cell fraction containing the ... subjecting the treated cell fraction containing the nucleated red blood cells to second density-gradient centrifugation to ... thereby avoiding the overlapping of the density of the nucleated red blood cells and the density of white blood cells each ... treating the cell fraction containing the nucleated red blood cells in such a manner that the density of the nucleated red ...
... of human lymphocytes obtained following NH4Cl induced red blood cell lysis and Ficoll-Hypaque density gradient centrifugation. ... of human lymphocytes obtained following NH4Cl induced red blood cell lysis and Ficoll-Hypaque density gradient centrifugation. ... of human lymphocytes obtained following NH4Cl induced red blood cell lysis and Ficoll-Hypaque density gradient centrifugation. ... of human lymphocytes obtained following NH4Cl induced red blood cell lysis and Ficoll-Hypaque density gradient centrifugation. ...
... depending on the density gradient media.. Please select your region. This is important to be able to checkout with correct ... During centrifugation, Leukocytes, lymphocytes and PBMCs are separated from unwanted erythrocytes and granulocytes, ...
Density Gradient Centrifugation. 2 × 107 uninfected or infected HL-60 cells were washed with ice-cold 1x PBS twice followed by ... were homogenized and the post-nuclear supernatants were separated by density gradient centrifugation. Successive one-ml ... Lysates of HL-60 cells, host cell-free A. phagocytophilum organisms, or gradient centrifugation fractions were analyzed by SDS- ... phagocytophilum infected HL-60 cells were fractionated by a continuous density gradient fractionation method that keeps the ApV ...
... followed by density gradient centrifugation using Larex (Stractan) or other gradient medium to remove other non-parenchymal ... Isolation of human HSC (fat-storing cells) was also reported in other studies using density gradient centrifugation method [31 ... Isolation of human HSCs using density gradient centrifugation. Friedman [23] first successfully isolated, cultured, and ... Isolation and culture of hepatic lipocytes, Kupffer cells, and sinusoidal endothelial cells by density gradient centrifugation ...
Sucrose density gradient centrifugation.. This was done according to a method described previously (6). In brief, INS cell ... INS cell cytosolic fraction was subjected to sucrose (5-20%) density gradient centrifugation (see research design and methods ... To this end, using Triton X-114 phase partition, co-immunoprecipitation, and sucrose density gradient centrifugation approaches ... Western blot analysis of individual fractions isolated from β-cell lysates subjected to sucrose density gradient centrifugation ...
Sucrose density gradient centrifugation of TX-100-insoluble fraction. Continuous sucrose density gradients (5-60% or 5-40%) in ... 1994) by sucrose density gradient centrifugation. Both fractions, in accordance with their detergent insolubility, densities ... The sucrose density gradient fractions from centrifugation of the pellet obtained by procedure 1 had very little actin or ... aDensity of spot on TLC plate as a percentage of total densities of all spots. bRatio of densities of cholesterol (chol), GalC ...
... obtained from Neurospora crassa grown under different conditions was investigated by density-gradient centrifugation on Percoll ... density 1·059; to 1·061; g ml-1) was also present in the stationary phase. When N. crassa was grown with acetate as the carbon ... The glyoxysomes were found to be less dense than the mitochondria and their density decreased from 1·076; to 1·055; g ml-1 as ... The buoyant density of isolated mitochondria and glyoxysomes ... conditions was investigated by density-gradient centrifugation ...
Apoptosis , Centrifugation , Centrifugation, Density Gradient , Chromatin , DNA Fragmentation , DNA , Methods , Product ... Centrifugation / Centrifugation, Density Gradient / Apoptosis / Product Packaging / DNA Fragmentation Clinical aspect: ... and to investigate the effects of density-gradient centrifugation (DGC) and magnetic-activated cell sorting (MACS) on reducing ... isolation of sperm with high DNA integrity and stable chromatin packaging by a combination of density-gradient centrifugation ...
Sucrose density gradient centrifugation. The cells were plated on 10-cm plates and transfected with 9 μg of total DNA per well ... A widely used approach in this category employs density gradient fractionation using either non-ionic detergent-based or ... Lubrol and separated into DRM and non-DRM fractions by sucrose gradient density fractionation at 180,000 × g for 18 h at 4°C. ... Lubrol and separated into DRM and non-DRM fractions by sucrose gradient density fractionation at 180,000 × g for 18 h at 4°C. ...
Sucrose-density-gradient centrifugation assays. COS-7 cells were harvested, lysed and sedimented as described in [40]. Briefly ... In addition, the fusion protein GST-4.1R60Δ16 behaved like GST-4.1R60Δ16,18 in sucrose-density-gradient centrifugation assays ( ... We next performed sucrose-density-gradient centrifugation assays using extracts from COS-7 cells transfected with 4.1R135Δ16- ... was analysed by sucrose-density-gradient centrifugation assays (Figure 4). Protein 4.1R80Δ16 fractionated at the top of the ...
Keywords: Aneuploidy; Density gradient centrifugation; DNA fragmentation; Sperm; Swim-up Introduction. The percentage of sperm ... SU, swim-up; DGC, density gradient centrifugation.. a)Sperm cells with a small halo or no halo, or that were degraded, when ... Swim-up and density gradient centrifugation (DGC) are commonly used sperm preparation methods for assisted conception [5]. ... The aim of this study was to compare the efficacy of swim-up and density gradient centrifugation (DGC) for reducing the amount ...
Density gradient centrifugation. Mitochondria were solubilized at 2 mg protein/ml in digitonin buffer for 20 min on ice and ... Furthermore, glycerol density gradient centrifugation of digitonin-solubilized mitochondria showed that Ups1p-Flag and Ups3p- ... Isolated mitochondria were solubilized in 1% digitonin and subjected to 20-40% glycerol density gradient centrifugation. In ... E) Mitochondria were solubilized with digitonin and subjected to glycerol density gradient centrifugation. Fractions were ...
OptiPrep density gradient centrifugation. The procedure was performed as previously described (Lobb et al., 2015) by using the ... 3 c). Together with the data on vesicle size, their buoyancies in density gradient centrifugation and their neutral ... 2 g). Subfractionation of EEVs by density gradient centrifugation and subsequent analyses by SDS-PAGE, Coomassie blue staining ... a buoyancy of 1.16-1.23 g/ml in density gradient centrifugation (Théry et al., 2006; Lobb et al., 2015), and a protein ...
Preparation of Enriched Plasma Membranes by Density Gradient Centrifugation-. A total of 5 × 108 cells were homogenized in 10 ... Percoll was removed by centrifugation of the fractions in 1-ml 1PC tubes at 900,000 × g in Sorvall RC M150 GX using the S150AT ... The gradient was fractionated from the top by the displacement method. In order to select fractions containing enriched plasma ... Homogenization and centrifugation were repeated. The post-nuclear supernatant was centrifuged at 50,000 × g for 30 min. The ...
Density gradient centrifugation. Lec-1 cells stably expressing GM or transiently expressing CD4 or sucrase-isomaltase were ... Our sucrose-density gradient analysis showed that an ERGIC-53 construct unable to form intermolecular disulfide bridges is ... It is difficult to correctly predict the size of the GM complexes from density gradients because the marker proteins are all ... Density gradient analysis may, therefore, underestimate the actual size of the GM complexes. Nevertheless, these experiments ...
Density Gradient Centrifugation by AUTHOR, UNKNOWN * PDF * £51.99 * Vitamin E Chemistry and Nutritional Benefits ...
Density Gradient Centrifugation Product Type: Book. Edition: 1. Volume: 6. First Published: 1978 ...
Density Gradient CentrifugationEdit. Density gradient centrifugation is considered one of the more efficient methods of ... Density gradient centrifugation can be used both as a separation technique and as a method of measuring the densities of ... which in fact have little to no density gradient.[7]. Differential CentrifugationEdit. Differential Centrifugation is a type of ... They used density gradient centrifugation to determine which isotope or isotopes of nitrogen were present in the DNA after ...
  • In particular, the present invention relates to the use of a cell-trap centrifugation tube containing a specific density gradient solution adjusted to the specific density of a desired cell population to enrich for the desired cell from a cell source. (freepatentsonline.com)
  • The tube allows the desired cell population to be collected by decantation after centrifugation to minimize cell loss and maximize efficiency. (freepatentsonline.com)
  • In addition, the method can be further simplified by density-adjusted cell sorting which uses cell type-specific binding agents such as antibodies and lectins linked to carrier particles to impart a different density to the undesired populations in a more convenient manner. (freepatentsonline.com)
  • The density gradient profiles and electrophoretic patterns of restriction endonuclease digests were identical among all the cell lines examined and were indistinguishable from those of the parental DC-3F DNA. (springer.com)
  • The ATPase associated with different cellular activities family member p97, associated p47, and the t-SNARE syntaxin 5 are necessary for the cell-free reconstitution of transitional endoplasmic reticulum (tER) from starting low-density microsomes. (pnas.org)
  • Leukemic blasts (mostly CD34 + ) from patients with acute myeloblastic leukemia (AML) expressed variable amounts of CXCR-4, which was functionally active, as demonstrated by a positive correlation between the SDF-1-induced transendothelial migration and the cell surface density of CXCR-4 (r = 0.97). (bloodjournal.org)
  • Intracellular fluid becomes hypotonic, water moves down its concentration gradient out of the cell. (wikipedia.org)
  • These membranes were then fractionated according to their density by centrifuging at 350,000 × g for 3 h in a VTi65.1 rotor (Beckman Coulter), during which time an iodixanol gradient is generated. (mcponline.org)