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, 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, 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.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)Povidone: A polyvinyl polymer of variable molecular weight; used as suspending and dispersing agent and vehicle for pharmaceuticals; also used as blood volume expander.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.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)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.Cell SeparationFiltration: 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)Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Kinetics: The rate dynamics in chemical or physical systems.TritiumSucrose: 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.Organoids: An organization of cells into an organ-like structure. Organoids can be generated in culture. They are also found in certain neoplasms.Cesium: 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.Methods: A series of steps taken in order to conduct research.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.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.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)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.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.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.Nucleotidases: A class of enzymes that catalyze the conversion of a nucleotide and water to a nucleoside and orthophosphate. EC 3.1.3.-.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)Diatrizoate: A commonly used x-ray contrast medium. As DIATRIZOATE MEGLUMINE and as Diatrizoate sodium, it is used for gastrointestinal studies, angiography, and urography.Acid Phosphatase: An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.2.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.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.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)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)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.Membranes: Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.Cell Line: Established cell cultures that have the potential to propagate indefinitely.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.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.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)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.Triiodobenzoic Acids: Triiodo-substituted derivatives of BENZOIC ACID.Cytoplasmic Granules: Condensed areas of cellular material that may be bounded by a membrane.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.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.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.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)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.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.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.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.Freezing: Liquids transforming into solids by the removal of heat.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.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).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.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.Microbodies: Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.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)Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.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.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.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)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)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.Blood Specimen Collection: The taking of a blood sample to determine its character as a whole, to identify levels of its component cells, chemicals, gases, or other constituents, to perform pathological examination, etc.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.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)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.Ribonucleases: Enzymes that catalyze the hydrolysis of ester bonds within RNA. EC 3.1.-.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.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.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.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.Pronase: A proteolytic enzyme obtained from Streptomyces griseus.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.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.Evaluation Studies as Topic: Studies determining the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies. For drugs and devices, CLINICAL TRIALS AS TOPIC; DRUG EVALUATION; and DRUG EVALUATION, PRECLINICAL are available.Time Factors: Elements of limited time intervals, contributing to particular results or situations.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.Sperm 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.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.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)Chemistry Techniques, Analytical: Methodologies used for the isolation, identification, detection, and quantitation of chemical substances.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.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)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.ThymidineDialysis: 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)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.Bacteriological Techniques: Techniques used in studying bacteria.Ribosomes: Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.Viruses, Unclassified: Viruses whose taxonomic relationships have not been established.Nucleoproteins: Proteins conjugated with nucleic acids.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.Cytosol: Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.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.Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Deoxyribonucleases: Enzymes which catalyze the hydrolases of ester bonds within DNA. EC 3.1.-.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.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)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.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.Tissue Extracts: Preparations made from animal tissues or organs (ANIMAL STRUCTURES). They usually contain many components, any one of which may be pharmacologically or physiologically active. Tissue extracts may contain specific, but uncharacterized factors or proteins with specific actions.UridineChemical Phenomena: The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.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.Specimen Handling: Procedures for collecting, preserving, and transporting of specimens sufficiently stable to provide accurate and precise results suitable for clinical interpretation.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.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.GlucuronidaseSwine: 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).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)Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Sonication: The application of high intensity ultrasound to liquids.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.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.Chlorides: Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.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.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)DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.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)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.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.Electron Transport Complex IV: A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Viral Proteins: Proteins found in any species of virus.Proteoglycans: Glycoproteins which have a very high polysaccharide content.Peptide Hydrolases: Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.Ultrafiltration: The separation of particles from a suspension by passage through a filter with very fine pores. In ultrafiltration the separation is accomplished by convective transport; in DIALYSIS separation relies instead upon differential diffusion. Ultrafiltration occurs naturally and is a laboratory procedure. Artificial ultrafiltration of the blood is referred to as HEMOFILTRATION or HEMODIAFILTRATION (if combined with HEMODIALYSIS).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.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.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.Mucins: High molecular weight mucoproteins that protect the surface of EPITHELIAL CELLS by providing a barrier to particulate matter and microorganisms. Membrane-anchored mucins may have additional roles concerned with protein interactions at the cell surface.Nucleic Acid Renaturation: The reformation of all, or part of, the native conformation of a nucleic acid molecule after the molecule has undergone denaturation.Malate Dehydrogenase: An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 1.1.1.37.Densitometry: The measurement of the density of a material by measuring the amount of light or radiation passing through (or absorbed by) the material.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.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.Blood: The body fluid that circulates in the vascular system (BLOOD VESSELS). Whole blood includes PLASMA and BLOOD CELLS.Bacterial Proteins: Proteins found in any species of bacterium.Spheroplasts: Cells, usually bacteria or yeast, which have partially lost their cell wall, lost their characteristic shape and become round.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.Microscopy, Phase-Contrast: A form of interference microscopy in which variations of the refracting index in the object are converted into variations of intensity in the image. This is achieved by the action of a phase plate.Hexosaminidases: Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.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.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.Alkaline Phosphatase: An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.1.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.Electrophoresis, Agar Gel: Electrophoresis in which agar or agarose gel is used as the diffusion medium.Extrachromosomal Inheritance: Vertical transmission of hereditary characters by DNA from cytoplasmic organelles such as MITOCHONDRIA; CHLOROPLASTS; and PLASTIDS, or from PLASMIDS or viral episomal DNA.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Gravitation: Acceleration produced by the mutual attraction of two masses, and of magnitude inversely proportional to the square of the distance between the two centers of mass. It is also the force imparted by the earth, moon, or a planet to an object near its surface. (From NASA Thesaurus, 1988)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.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)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.Leucine: An essential branched-chain amino acid important for hemoglobin formation.Sulfates: Inorganic salts of sulfuric acid.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)Coxiella: A genus of gram-negative, rod-shaped bacteria that is widely distributed in TICKS and various mammals throughout the world. Infection with this genus is particularly prevalent in CATTLE; SHEEP; and GOATS.Microbiological Techniques: Techniques used in microbiology.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.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)Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Cryopreservation: Preservation of cells, tissues, organs, or embryos by freezing. In histological preparations, cryopreservation or cryofixation is used to maintain the existing form, structure, and chemical composition of all the constituent elements of the specimens.Cytochrome ReductasesCytochromes: Hemeproteins whose characteristic mode of action involves transfer of reducing equivalents which are associated with a reversible change in oxidation state of the prosthetic group. Formally, this redox change involves a single-electron, reversible equilibrium between the Fe(II) and Fe(III) states of the central iron atom (From Enzyme Nomenclature, 1992, p539). The various cytochrome subclasses are organized by the type of HEME and by the wavelength range of their reduced alpha-absorption bands.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Oxidoreductases: The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)Semen Preservation: The process by which semen is kept viable outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).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)Lymphocytes: White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.Cell-Derived Microparticles: Extracellular vesicles generated by the shedding of CELL MEMBRANE blebs.Hydrolases: Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.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.Ovum: A mature haploid female germ cell extruded from the OVARY at OVULATION.Microsomes, Liver: Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.Ethylmaleimide: A sulfhydryl reagent that is widely used in experimental biochemical studies.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.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.Chloroform: A commonly used laboratory solvent. It was previously used as an anesthetic, but was banned from use in the U.S. due to its suspected carcinogenicity.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.Haplorhini: A suborder of PRIMATES consisting of six families: CEBIDAE (some New World monkeys), ATELIDAE (some New World monkeys), CERCOPITHECIDAE (Old World monkeys), HYLOBATIDAE (gibbons and siamangs), CALLITRICHINAE (marmosets and tamarins), and HOMINIDAE (humans and great apes).Protamines: A group of simple proteins that yield basic amino acids on hydrolysis and that occur combined with nucleic acid in the sperm of fish. Protamines contain very few kinds of amino acids. Protamine sulfate combines with heparin to form a stable inactive complex; it is used to neutralize the anticoagulant action of heparin in the treatment of heparin overdose. (From Merck Index, 11th ed; Martindale, The Extra Pharmacopoeia, 30th ed, p692)Semen Analysis: The quality of SEMEN, an indicator of male fertility, can be determined by semen volume, pH, sperm concentration (SPERM COUNT), total sperm number, sperm viability, sperm vigor (SPERM MOTILITY), normal sperm morphology, ACROSOME integrity, and the concentration of WHITE BLOOD CELLS.MercaptoethanolMicrovilli: Minute projections of cell membranes which greatly increase the surface area of the cell.Ammonium Sulfate: Sulfuric acid diammonium salt. It is used in CHEMICAL FRACTIONATION of proteins.Ficoll: A sucrose polymer of high molecular weight.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.Blood Platelets: Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.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.Adsorption: The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.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)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.

Nuclear chromatin variations in human spermatozoa undergoing swim-up and cryopreservation evaluated by the flow cytometric sperm chromatin structure assay. (1/1626)

The sperm chromatin structure assay (SCSA) is a flow cytometric (FCM) technique which exploits the metachromatic properties of Acridine Orange to monitor the susceptibility of sperm chromatin DNA to in-situ acid denaturation. SCSA was used to study the chromatin structure variations of human spermatozoa in semen, both before and after swim-up and after cryopreservation. Semen samples were provided by 19 healthy normozoospermic subjects attending pre-marriage checks. Each sample was divided into three aliquots: the first aliquot was evaluated without further treatment, the second underwent swim-up, and the third was stored according to standard cryopreservation techniques in liquid nitrogen at -196 degrees C. Samples were also analysed by light and fluorescence microscopy (after Acridine Orange staining to evaluate the number of green fluorescent sperm heads), and by computer-assisted semen analysis. The results showed that post-rise spermatozoa represent a subpopulation characterized by a general improvement of the morphological (reduction of the percentage of abnormal forms and heads, increase of the green head sperm percentage) and kinetic parameters. This subpopulation also exhibited improved chromatin structure properties, confirming that these cells have the best structural and functional characteristics, indicative of optimal fertilizing ability. On the other hand, overall sperm quality deteriorates after cryopreservation. When thawed spermatozoa underwent an additional swim-up round, a general improvement of nuclear maturity was seen in the post-rise spermatozoa.  (+info)

Mechanically induced c-fos expression is mediated by cAMP in MC3T3-E1 osteoblasts. (2/1626)

In serum-deprived MC3T3-E1 osteoblasts, mechanical stimulation caused by mild (287 x g) centrifugation induced a 10-fold increase in mRNA levels of the proto-oncogene, c-fos. Induction of c-fos was abolished by the cAMP-dependent protein kinase inhibitor H-89, suggesting that the transient c-fos mRNA increase is mediated by cAMP. Down-regulation of protein kinase C (PKC) activity by chronic TPA treatment failed to significantly reduce c-fos induction, suggesting that TPA-sensitive isoforms of PKC are not responsible for c-fos up-regulation. In addition, 287 x g centrifugation increased intracellular prostaglandin E2 (PGE2) levels 2.8-fold (P<0. 005). Since we have previously shown that prostaglandin E2 (PGE2) can induce c-fos expression via a cAMP-mediated mechanism, we asked whether the increase in c-fos mRNA was due to centrifugation-induced PGE2 release. Pretreatment with the cyclooxygenase inhibitors indomethacin and flurbiprofen did not hinder the early induction of c-fos by mechanical stimulation. We conclude that c-fos expression induced by mild mechanical loading is dependent primarily on cAMP, not PKC, and initial induction of c-fos is not necessarily dependent on the action of newly synthesized PGE2.  (+info)

A novel strategy for the preparation of liposomes: rapid solvent exchange. (3/1626)

During the preparation of multi-component model membranes, a primary consideration is that compositional homogeneity should prevail throughout the suspension. Some conventional sample preparation methods pass the lipid mixture through an intermediary, solvent-free state. This is an ordered, solid state and may favor the demixing of membrane components. A new preparative method has been developed which is specifically designed to avoid this intermediary state. This novel strategy is called rapid solvent exchange (RSE) and entails the direct transfer of lipid mixtures between organic solvent and aqueous buffer. RSE liposomes require no more than a minute to prepare and manifest considerable entrapment volumes with a high fraction of external surface area. In phospholipid/cholesterol mixtures of high cholesterol content, suspensions prepared by more conventional methods reveal evidence of artifactual demixing, whereas samples prepared by rapid solvent exchange do not. The principles which may lead to artifactual demixing during conventional sample preparation are discussed.  (+info)

Chromosome-membrane association in Bacillus subtilis. IV. Further purification of DNA-membrane complex by using a combination of centrifugation and electrophoresis. (4/1626)

We have developed a simple procedure to purify a DNA-membrane complex from Bacillus subtilis by using a combination of centrifugation and electrophoresis. Several unique proteins were detected in the purified complex.  (+info)

Vasopressin regulates apical targeting of aquaporin-2 but not of UT1 urea transporter in renal collecting duct. (5/1626)

In the renal inner medullary collecting duct (IMCD), vasopressin regulates two key transporters, namely aquaporin-2 (AQP2) and the vasopressin-regulated urea transporter (VRUT). Both are present in intracellular vesicles as well as the apical plasma membrane. Short-term regulation of AQP2 has been demonstrated to occur by vasopressin-induced trafficking of AQP2-containing vesicles to the apical plasma membrane. Here, we have carried out studies to determine whether short-term regulation of VRUT occurs by a similar process. Cell surface labeling with NHS-LC-biotin in rat IMCD suspensions revealed that vasopressin causes a dose-dependent increase in the amount of AQP2 labeled at the cell surface, whereas VRUT labeled at the cell surface did not increase in response to vasopressin. Immunoperoxidase labeling of inner medullary thin sections from Brattleboro rats treated with 1-desamino-8-D-arginine vasopressin (DDAVP) for 20 min revealed dramatic translocation of AQP2 to the apical region of the cell, with no change in the cellular distribution of VRUT. In addition, differential centrifugation of inner medullary homogenates from Brattleboro rats treated with DDAVP for 60 min revealed a marked depletion of AQP2 from the low-density membrane fraction (enriched in intracellular vesicles) but did not alter the quantity of VRUT in this fraction. Finally, AQP2-containing vesicles immunoisolated from a low-density membrane fraction from renal inner medulla did not contain immunoreactive VRUT. Thus vasopressin-mediated regulation of AQP2, but not of VRUT, depends on regulated vesicular trafficking to the plasma membrane.  (+info)

Evidence that the co-chaperone p23 regulates ligand responsiveness of the dioxin (Aryl hydrocarbon) receptor. (6/1626)

The dioxin (aryl hydrocarbon) receptor is a ligand-dependent transcription factor that induces expression of a number of genes encoding drug metabolizing enzymes. In the absence of ligand the dioxin receptor is present in the cytoplasmic compartment of the cell associated with the molecular chaperone hsp90, which has been implicated in regulating the correct folding of the ligand binding domain of the receptor. In this study we have examined a potential role of the hsp90-associated p23 protein in the activation process of the dioxin receptor to a DNA binding form. In an in vitro model we show that addition of ligand alone to the dioxin receptor fails to induce release of hsp90 from the dioxin receptor. In the presence of ligand, this release was, however, induced upon addition of purified preparations of Arnt. Interestingly, p23 was also found to be associated with the nonactivated form of the dioxin receptor. Following fractionation on sucrose gradients p23 was dissociated from the receptor-hsp90 complex generating a receptor form, which showed ligand-independent release of hsp90 by Arnt and, consequently, ligand-independent activation of the DNA binding activity of the dioxin receptor. Ligand dependence was reconstituted in the presence of molybdate, a transition metal ion known to stabilize the interaction between the molecular chaperone hsp90 and p23. Taken together these experiments suggest a role of p23 in modulating ligand responsiveness in the activation process of the dioxin receptor.  (+info)

Visualizing ion relaxation in the transport of short DNA fragments. (7/1626)

Ion relaxation plays an important role in a wide range of phenomena involving the transport of charged biomolecules. Ion relaxation is responsible for reducing sedimentation and diffusion constants, reducing electrophoretic mobilities, increasing intrinsic viscosities, and, for biomolecules that lack a permanent electric dipole moment, provides a mechanism for orienting them in an external electric field. Recently, a numerical boundary element method was developed to solve the coupled Navier-Stokes, Poisson, and ion transport equations for a polyion modeled as a rigid body of arbitrary size, shape, and charge distribution. This method has subsequently been used to compute the electrophoretic mobilities and intrinsic viscosities of a number of model proteins and DNA fragments. The primary purpose of the present work is to examine the effect of ion relaxation on the ion density and fluid velocity fields around short DNA fragments (20 and 40 bp). Contour density as well as vector field diagrams of the various scalar and vector fields are presented and discussed at monovalent salt concentrations of 0.03 and 0.11 M. In addition, the net charge current fluxes in the vicinity of the DNA fragments at low and high salt concentrations are briefly examined and discussed.  (+info)

Characterization of Fus3 localization: active Fus3 localizes in complexes of varying size and specific activity. (8/1626)

The MAP kinase Fus3 regulates many different signal transduction outputs that govern the ability of Saccharomyces cerevisiae haploid cells to mate. Here we characterize Fus3 localization and association with other proteins. By indirect immunofluorescence, Fus3 localizes in punctate spots throughout the cytoplasm and nucleus, with slightly enhanced nuclear localization after pheromone stimulation. This broad distribution is consistent with the critical role Fus3 plays in mating and contrasts that of Kss1, which concentrates in the nucleus and is not required for mating. The majority of Fus3 is soluble and not bound to any one protein; however, a fraction is stably bound to two proteins of approximately 60 and approximately 70 kDa. Based on fractionation and gradient density centrifugation properties, Fus3 exists in a number of complexes, with its activity critically dependent upon association with other proteins. In the presence of alpha factor, nearly all of the active Fus3 localizes in complexes of varying size and specific activity, whereas monomeric Fus3 has little activity. Fus3 has highest specific activity within a 350- to 500-kDa complex previously shown to contain Ste5, Ste11, and Ste7. Ste5 is required for Fus3 to exist in this complex. Upon alpha factor withdrawal, a pool of Fus3 retains activity for more than one cell cycle. Collectively, these results support Ste5's role as a tether and suggest that association of Fus3 in complexes in the presence of pheromone may prevent inactivation in addition to enhancing activation.  (+info)

Cytomegalovirus infection remains a major cause of morbidity and mortality in marrow transplant recipients. Results of a rapid centrifugation viral culture of bronchoalveolar lavage specimens from 33 marrow transplant recipients with pneumonia were compared with those for conventional viral culture of concurrently or subsequently obtained lung tissue. The centrifugation culture results were also compared to results of cytologic and immunochemical examination of these specimens. Centrifugation culture was positive within 16 hours of inoculation in 22 of 23 (96%) specimens from patients with positive conventional culture of lung tissue. Detection of cells positive for cytomegalovirus by immunofluorescent antibody staining or cytologic identification was less sensitive (59% and 29%, respectively). There was no evidence of cytomegalovirus in specimens from patients without evidence of cytomegalovirus pulmonary infection by any technique. The sensitivity (96%) and specificity (100%) of centrifugation ...
A prototype CFSM will be further developed to facilitate single-molecule manipulation. A sealed gasket encloses the sample chamber, which will be mounted on a spinning compact disk (see figure). A ds-DNA library, containing important transcription initiation and termination sequences, will be spotted on the lower surface of the sample chamber using DNA microarray technology. Each ds-DNA, prepared with biotin at its distal end, will bind a strepavidin-coated fluorescent microsphere. The centrifugal force will push (when viewed in a rotating frame of reference) these microspheres radially and so cause the attached ds-DNA to stretch. The laser on a modified compact disk player will be used to track the bead displacement. The centrifugal force on each microsphere can be calculated based on their size, density and radial velocity. The centrifugal force plotted against microsphere displacement will provide information about the physical properties (persistence length, overstretching transition, etc) ...
TY - GEN. T1 - Magnetic assistance for suppressing cross-reactions between biomolecules in immunoassay. AU - Hong, Chin Yih. AU - Yang, Shieh Yueh. AU - Horng, Herng Er. AU - Yang, Hong Chang. PY - 2010/12/1. Y1 - 2010/12/1. N2 - A method involving the use of magnetic nanoparticles to suppress the cross-reactions in immunoassay is developed. Antibodies are coated onto magnetic nanoparticles. These antibodies bind with target and non-target molecules. Once an alternative-current magnetic field is applied, magnetic nanoparticles oscillate with the magnetic field. The target and non-target molecules attached onto magnetic nanoparticles via antibodies experience a centrifugal force, which is against the association between antibodies and target/non-target molecules. Theoretically, the centrifugal force is proportional to the square of the frequency of the applied magnetic field. Thus, the strength of the centrifugal force can be manipulated by changing the frequency of the applied magnetic field. By ...
Thus, we see that the centripetal force acting on a body is always provided by some other type of force -- centripetal force, thus, is simply a name to indicate the force that provides this circular motion. This centripetal force is always acting inward toward the center. You will know this if you swing an object in a circular motion. If you notice carefully, you will see that you have to continuously pull inward. We know that an opposite force should exist for this centripetal force(by Newtons 3rd Law of Motion). This is the centrifugal force, which exists only if we study the body from a non-inertial frame of reference(an accelerating frame of reference, such as in circular motion). This is a so-called pseudo-force, which is used to make the Newtons law applicable to the person who is inside a non-inertial frame. e.g. If a driver suddenly turns the car to the left, you go towards the right side of the car because of centrifugal force. The centrifugal force is equal and opposite to the ...
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Neuation offers a wide range of next generation Centrifuges for various Research lab applications. From personal centrifuge to Universal laboratory centrifuges the range of Micro centrifuges and Lab centrifuges are widely used in microbiology, tissue culture, molecular biology, clinical and blood banking, drug discovery, genomics and proteomics. Neuation products are designed and developed by it own R & D team. Employing a User Centric Design Process to develop simple, Safe, easy of use and high performance laboratory centrifuges. The products are CE certified and approved for IVD use.
Neuation offers a wide range of next generation Centrifuges for various Research lab applications. From personal centrifuge to Universal laboratory centrifuges the range of Micro centrifuges and Lab centrifuges are widely used in microbiology, tissue culture, molecular biology, clinical and blood banking, drug discovery, genomics and proteomics. Neuation products are designed and developed by it own R & D team. Employing a User Centric Design Process to develop simple, Safe, easy of use and high performance laboratory centrifuges. The products are CE certified and approved for IVD use.
It is true that centrifugal force on earth has its counterpart in centripetal force, in gravity, but it would be pure foolishness to presume that centrifugal force -- i.e., fleeing away from the center of mass -- holds the wheat-stalk upright, or allows trees to dance lithely in the air, or causes millions of other plants, grasses and climbing vines to writhe ecstatically toward the heavens. Human ingenuity cannot produce the miracle of the wheat-stalk, the spiralling morning glory vine, or a massive sequoia tree. In terms of engineering these are living design miracles that defy both gravity and mechanical law. Nothing constructed by human skill could be so supple and yet so stable. Constructed on terrestrial principles, the wheat stalk is nevertheless incapable of standing tall and steady due to terrestrial laws alone. It needs the co-emergence of Andromedan physics. The plant-world on earth mirrors the physics of beauty, the aesthetic laws that prevail on Andromeda. Van Goghs sunflowers grow ...
A device for analysis used for transferring a solution to a measurement spot 38 by a centrifugal force and reading in which a reaction liquid located at the measurement spot 38 is optically accessed. An operation cavity 30 and a receiving cavity 32 are arranged from the upstream side to the downstream side of the transfer. The operation cavity 30 and the receiving cavity 32 communicate with each other via a connection section 59 to transfer the solution of the operation cavity 30 to the receiving cavity 32. The connection section 59 is located inside the liquid level of a diluted solution retained in the operation cavity 30, relative to a rotation axis 102.
Mechanically Operated Centrifugal Switch - An electric switch that operates using the centrifugal force created from a rotating shaft. The switch is designed to activate or de-activate as a function of the rotational speed of the shaft. In single-phase, split-phase induction motors, the switch is used to disconnect the starting winding of the motor once the motor approaches its normal operating speed. The centrifugal switch consists of weights mounted to the shaft of the motor and held near the shaft by spring force. At rest, levers attached to the weights press a low-friction, non-conductive plate against a set of electrical contacts mounted to the motor housing, closing the contacts and connecting the starting winding to the power source. When the motor approaches its normal operating speed, centrifugal force overcomes the spring force and the weights swing out, raising the plate away from the electrical contacts. This allows the contacts to open and disconnects the starting winding from the ...
Synonyms for Centrifugal acceleration in Free Thesaurus. Antonyms for Centrifugal acceleration. 1 antonym for centrifugal force: centripetal force. What are synonyms for Centrifugal acceleration?
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)
Cyclones are not as efficient (99.5%) as bag filters but several can be placed in series. Air enters at tangent at high velocity into a cylinder or cone which has a much larger cross section. Air velocity is decreased in the cone permitting settling of solids by gravity. Centrifugal force is important in removing particles from the air stream. High air velocity is needed to separate small diameter and light materials from air; velocities may approach 100 ft/sec (70 MPH). Higher centrifugal force can be obtained by using small diameter cyclones, several of which may be placed in parallel; losses may range from 0.5-2%. A rotary airlock is used to remove powder from the cyclone. (An example of a rotary airlock is a revolving door at a hotel lobby which is intended to break the outside and inside environments).. ...
Coupling greases, unlike bearing or general purpose grease, must withstand the centrifugal forces created by a rotating coupling. These greases - KSG and KHP - are specifically formulated to resist the heavy centrifugal forces associated with all applications. These forces can cause the all-important base oil to separate from the soap thickeners and additives. Unlike greases with lithium-based thickeners, KSG and KHP greases use polyethylene thickeners, with a density closer to that of the base oil, and therefore much less susceptible to separation ...
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A centrifugal machine, also known as a centrifuge, is an important part of any hospital, health care or testing laboratory. These essential pieces of equipment are used daily to generate extremely high rotating speeds, creating a centrifugal force that forces materials of different densities to separate. Of course these materials do need to be in a suspension for the process to work, but they are perfect for separating the solids from the liquids and distinguishing between materials of different weights and densities within the suspension.
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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 ...
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 ...
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).. ...
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... , The operator should not leave the centrifuge until full operating speed is attained and the machine appears to be running safely without vibration. Stop the centrifuge immediately if an unusual condition (noise or vibration) begins and check load balances. After Centrifugation. Allow the centrifuge to come to a complete stop before opening.
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An evacuated tube having both ends closed has a centrifugally actuated slit type valve fixedly disposed between the ends for dividing the tube into upper and lower chambers. The valve is formed and arranged to provide a passageway between the upper and lower chambers when subjected to a centrifugal force of proper intensity and direction. Upon cessation of the force, the valve closes to provide a separation between the upper and lower chambers.
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Looking for plasma centrifuge? Find out information about plasma centrifuge. A device for separating isotopes in which a cylinder of ionized matter is contained by a magnetic field and set into rotation by application of an... Explanation of plasma centrifuge
15 Ml Centrifuge Tubes found in: High-Speed Diamond Max™ Centrifuge Tubes, 15 mL Centrifuge Test Tubes, Centrifuge Tubes, 15 and 50 mL Conical Tubes,..
Alibaba.com offers 2,495 table top centrifuge products. About 75% of these are laboratory centrifuge, 3% are separation equipment. A wide variety of table top centrifuge options are available to you, such as paid samples, free samples.
... - Modèle CLS-4208 (). These tubes and accessories simplify the anaerobic methods in several areas of microbiology.
The most common density gradient centrifugation method uses Ficoll Paque®, a solution of high molecular weight sucrose polymers. A blood sample is centrifuged in a tube containing the density gradient medium to separate its components according to their densities. Erythrocytes have a higher density than plasma, and so become packed in the bottom of the tube to make up 45% of the total volume (in blood from healthy donors). This volume percentage is known as hematocrit. Leukocytes and platelets form a narrow buff-colored layer (buffy coat) immediately above the erythrocytes. Finally, plasma makes up just under 55% of the total volume and is a pale yellow fluid. The buffy coat contains lymphocytes, monocytes, and platelets and is harvested for two subsequent centrifugations in a buffered salt solution to wash the PBMCs and remove the platelets. The resulting PBMCs can be used for the isolation of cell subtypes or other experimental procedures. A protocol for the isolation of PBMCs from blood by ...
Allogeneic MSCs being used in current human clinical trials are nonclonal, i.e., such MSCs may have other types of cells in the final stem cell product. Some concerns exist about the heterogeneity of these nonclonal MSCs that are isolated and expanded by the conventional density-gradient centrifugation method. Recently, we developed a new protocol, called the subfractionation culturing method (SCM), to generate single-cell-derived clonal MSC (cMSC) lines from whole bone marrow aspirate without employing any centrifugation step for mononuclear cells and enzyme treatment process. This method allowed us to rapidly establish single-cell-derived human clonal MSC (hcMSC) lines from raw bone marrow aspirates and to establish a library of these hcMSC lines (Song et al., 2008).. The goal of this study is to evaluate the safety of allogeneic cMSCs established by the SCM and manufactured in GMP facility. This phase I clinical trial is a multicenter, single dose study of cMSC (1 x 10e6 cMSCs/Kg recipients ...
Definition of elutriation in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is elutriation? Meaning of elutriation as a legal term. What does elutriation mean in law?
MODEL RELEASED. Biological research. Researcher operating a high-speed centrifuge (cell separator) to separate a cell suspension into its constituent parts using centrifugal force. Photographed at the Genethon Laboratory, near Paris, France. - Stock Image G350/0506
DA-Cell solution enables sample preparation for multi- color flow cytometry and bypasses the need of centrifugation for washing suspension cells. The DA-Cell technology is designed to maintain samples in a 96 droplet based format instead of using a conventional microwell with walls (Figure 1B). DA-Cell is a centrifuge-less processing method using the unique wall-less features of the DropArray technology combined with a fully automated washer. The DA-Cell washer generates a laminar flow for each drop on the DA-Cell plate via dual-nozzle action, with one nozzle dispensing liquid into the drop and the other nozzle aspirating liquid. The DA-Cell workflow is superior over the traditional centrifugation method:. ...
To meet stringent limit-of-detection specifications for low abundance target molecules, a relatively large volume of plasma is needed for many blood-based clinical diagnostics. Conventional centrifugation methods for plasma separation are not suitable for on-site testing or bedside diagnostics. Here, we repo
A cartridge is provided to present a biological sample for analysis by an imaging instrument. The cartridge of the invention utilizes a series of channels, capillaries, reservoirs and stop junctions to precisely move a sample, reagent and diluent through the cartridge as a function of the sum of capillary, gravitational and low centrifugal forces. The operator applies a precise amount of sample to the cartridge; therefore, the cartridge fluidics need not meter the sample prior to dilution. A practical and cost effective cartridge and assay process is disclosed which overcomes many of the limitations of the prior art. Such a cartridge is especially useful with fixed volume assays which permit low centrifugal accelerations to move the fluids within the cartridge.
... ,Thermo Savant SpeedVac Concentrators set the standard for centrifugal concentration and drying. The classic series SC110A SpeedVac uses a combination of centrifugal force, heat and vacuum to dry multiple samples in a single run.,, SC110A comes equipped with:, , TEFLON-coated Rotor Cham,biological,biology supply,biology supplies,biology product
These Oberdorfer™ centrifugal pumps have a single open vane rotating impeller. Liquid enters at the center and is thrown outward radically by centrifugal force. The impeller is not in contact with other pump parts resulting in quiet, efficient pumping action. The flow produced is not positive which permits the discharge line to be shut off completely without danger of overloading motors or bursting lines. Consequently, a relief valve is not required. The flow of these pumps can be conveniently controlled... Go ...
These Oberdorfer™ centrifugal pumps have a single open vane rotating impeller. Liquid enters at the center and is thrown outward radically by centrifugal force. The impeller is not in contact with other pump parts resulting in quiet, efficient pumping action. The flow produced is not positive which permits the discharge line to be shut off completely without danger of overloading motors or bursting lines. Consequently, a relief valve is not required. The flow of these pumps can be conveniently controlled... Go ...
A simple method for the isolation of intact islets from the normal rat pancreas is described. The method is based upon disruption of the acinar parenchyma by injecting Hanks solution into the pancreatic duct system followed by incubation of the pancreas in collagenase. Islets can be separated rapidly from this mixture by sedimentation. The isolated islets release insulin in vitro and appear normal by light and electron microscopy after incubation. A centrifugation method is also described for isolation of large quantities of islets for biochemical studies.. ...
... ,The IEC CL40 and FL40 Centrifuge Series from Thermo Electron combines power, safety and versatility to increase your productivity in the lab. Available with a broad array of rotors and accessories for high-volume blood tube processing and microplate applications, the IEC CL40 and FL40 Centrifuge Se,medicine,medical supply,medical supplies,medical product
Corning™ Centrifuge Tubes with CentriStar™ Cap 50mL; Max. RCF: 15500xG; Cap and rack included Corning™ Centrifuge Tubes with CentriStar™ Cap...
attempting to enter the bearing housing is captured in the outer labyrinth paths and expelled through a port in the rotor by centrifugal force and gravity. The Bearing Isolator was invented to replace lip seals as a sealing solution in industrial process equipment, such as pumps, motors, gearboxes, pillow blocks and other types of rotating equipment. Because of their contacting design, friction against the shaft limits the life span of lip seals to approximately 3000 hours. Alternatively, an Inpro/Seal Bearing Isolator lacks ...
MIDSCI offers a range of centrifuges from mini and microcentrifuges, to high capacity benchtop centrifuges, both refrigerated and ambient, from Hettich & Hermle
Compressibility of particulate structures is a key factor in the behavior of all solid/liquid separation equipment. Particulate aggregation in suspensions determines the degree of compressibility, which is controlled by suitable pretreatment processes. As increasing thicknesses of deposits cover the separation surfaces, developing stresses continually compress the particulate bed. The principal sources of stress are (1) the unbuoyed weight in gravity thickeners, (2) centrifugal forces, (3) pump pressure converted into Darcian drag at the particle surfaces, and (4) surface forces developed by pressure-actuated impermeable membranes.. When stress is applied to a bed of flocculated particles, the bed is compressed by particle movement into open pores until no further movement into the interstices can occur. Any further deformation of the bed results in particle deformation or breakage. The porosity of the compressed floc is a function of the initial structure and particle shape - spherical ...
The present invention provides significant improvements in the design and performance of a specific type of Rotary Membrane Filter (RMF) apparatus which has the capability of separating particles from a fluid having the same and nearly the same density as the particles by utilizing shear to achieve separation, not centrifugal forces. A particular application for the apparatus is in the processing of fluid suspensions in which the suspensions contain fragile particles which are subject to damage due to excessive shear stresses. The prior art describes processing at constant shear rate, whereas the present invention provides the design and optimization of operation of such an apparatus at constant shear stress, which is maintained at a value below that at which significant damage to the fragile particles is encountered. The use of the invention in plasmapheresis (blood separations) is described in detail, it being understood that the teachings of the invention are also directly applicable to other fluids
In this paper, consideration is given to the dynamic response of a rotating cantilever twisted and inclined airfoil blade subjected to contact loads at the free end. Starting with the basic geometrical relations and energy formulation for a rotating Timoshenko beam constrained at the hub in a centrifugal force field, a system of coupled partial differential equations are derived for the combined axial, lateral and twisting motions which includes the transverse shear, rotary inertia, and Coriolis effects, as well. In the mathematical formulation, the torsion of the thin airfoil also considers a very general case of shear center not being coincident with the CG (center of gravity) of the cross section, which allows the equations to be used also for analyzing eccentric tip-rub loading of the blade. Equations are presented in terms of axial load along the longitudinal direction of the beam which enables us to solve the dynamic pulse buckling due to the tip being loaded in the longitudinal as well as ...
The visit to our tiny bit of virgin jungle was just one of many treats we enjoyed during the trip. Ecuador has its ups and downs (Ill send a more detailed report on the country later), but two facts never change. First the Equator has a special energy. You can feel it. You can even see it on the scales. You weigh less on the equator because of the earths centrifugal force. This seems to add a special health benefit and reminded me of an important health tip that Merri and I often use.. One reason for our journey south was to conduct a Global Health Secrets course at La Mirage Spa. The delegates who attended had health goals that ranged from just tuning up to recovering from serious illnesses, yet all who visited the Shamana at the spa received treatment for improving their lymph system.. The lymph is one of our bodies most important immune and purification systems and it is driven very much by gravity. Thus it occurred to me while seeing the Shamana place such import on this aspect of healing ...
An electro-analytical cartridge adapted for use in analyzing fluids. The cartridge includes an electrochemical device that measures ionic activity using ion-specific electrodes. The cartridge further includes a plumbing system composed of the electrochemical device and various wells or chambers which are interconnected by passageways. After introduction into the cartridge, liquid samples are measured out and transported to the electrochemical device utilizing a sequential application of centrifugal force followed by pressurization of the system. Reference fluid is transported from a reference fluid well or reservoir to the electrochemical device for use in measuring ionic activity. The cartridge may be used to measure the ionic activity of a wide variety of ions in fluids including bodily fluids.
The water pump uses centrifugal force to send coolant to the outside while it spins, drawing coolant from the centre continuously. The pump inlet is located close to the centre so that coolant returning from the radiator strikes the pump vanes, which then fling the coolant to the outside of the pump to enter the engine. Coolant leaving the pump first flows through the engine block and cylinder head, then through the radiator and finally back to the pump ...
I dont think that the temperature has anything to do with it, as Ive seen it in many runners at Ice Age where the temperatures were in the 80-90 F range. I think that there is a *big* electrolyte component to this phenomenon, but I am not willing to say that it is due to excess or depletion of electrolytes OR a state of over hydration. Instead, I think it more an issue of fluid-electrolyte BALANCE than anything. Ive heard the centrifugal force argument from the exercise scientists for years. I still dont buy into it as being the major cause of hand and foot edema during ultras. Why? I used to swell, but I dont anymore. The key *for me* has been an increase in electrolyte intake. Rich says that extra salt (due to over hydration?-- I admit, Im a bit confused by what you mean) and fluid volume would increase blood pressure. I agree, but consider this: 1) During exercise, systolic blood pressure is already extremely high. I doubt that the increase due to any excess fluid would be noticed in ...
The next time he started to run was quite a bit faster and he wasnt responding to me at all. I was bouncing all over the place until my left foot bounced out of the stirrup leaving me nothing to stand on. We were just rounding a corner and the centrifugal force pushed me over. I went down hard. The one thing I remember as it was happening was my head smashing on the ground. It really hurt. My head turned out to be the least of my worries. On the way down I twisted in the air so I landed more toward the right side of my butt then my head hit in the back and I continued to flip over. Im pretty sure I ended up sitting up on my knees. I remember yelling for Jen to help as he was running but there was just nothing she could do. She and the kids came running over. A car happened to be driving by on the middle of nowhere road and saw me fall so they drove up to see if I was ok. I wasnt dizzy and I could move all of my limbs so I got up and we walked to the barn. Well, I limped. I was pretty sore. By ...
The machine provides impressive traction, particularly on wet soil, thanks to higher frequency, higher centrifugal force and higher amplitude. The new models also feature better ergonomics and improved access for service and maintenance ...
Mince 100 g C. quinoa leaves in 100 ml of a solution containing 2.5% Na2B4O7. 10 H2O, 2.69% H3BO4, 0.2% ascorbic acid and 0.2% Na2SO3 at pH 7.8. Centrifuge expressed sap at low speed. To 1 vol. of the supernatant fluid add 0.15 vol. of 0.4% silver nitrate and leave at room temperature for 2-3 h. Centrifuge at low speed and stir 1 vol. of supernatant fluid with 0.25 vol. of chloroform for 10 min. Centrifuge at low speed and add 4% (w/v) of polyethylene glycol 6000 to the supernatant fluid. Leave at 4°C overnight. Centrifuge at low speed, resuspend the pellets in 10 ml of a solution containing 2.5% Na2B4O7. 10 H2O, 2.69% H3BO4, 3% urea and 0.1% (v/v) 2-mercaptoethanol at pH 7.8. Subject the virus to 1 or 2 cycles of differential centrifugation and purify further by sucrose density gradient centrifugation (Koenig et al., 1983).. ...
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For the preparation of synaptosomes, striatal tissue from adult mice (20-30 gm) was dissected and then homogenized in 4 ml of 0.32 m sucrose and 1 mm EDTA in an "AA" Wheaton glass-Teflon homogenizer (Thomas Scientific, Swedesboro, NJ). The supernatant fraction remaining after low-speed centrifugation (1500 × g, 7 min) was divided into two equal portions and applied to two identical discontinuous Percoll (Amersham Biosciences, Piscataway, NJ) gradients, which were centrifuged at 50,000 × g for 5 min (Dunkley et al., 1986). The material that migrated to the 10/15 and 15/23% Percoll boundaries was collected and washed in basal buffer (in mm: 145 NaCl, 2.7 KCl, 1.0 MgCl2, 10 glucose, and 10 HEPES-Tris, pH 7.4) by two 7 min centrifugation steps at 12,000 × g. The final pellet was resuspended in basal buffer and stored on ice until use.. In a typical experiment, a 40 μl portion of the synaptosomal suspension containing ∼ 50 μg of protein was combined with 10 μl of [3H] dopamine (28.0 Ci/mmol; ...
The Grant bio Combi-spin PCV-2400 is a fixed-speed combined centrifuge/vortex mixer for combined or independent centrifuge and mixing applications of microtubes and 0.2 ml microtube strips in low volume applications. Combi-spin aids the sample preparation process for many procedures including PCR, gel electrophoresis and enzyme reactions, and is particularly suitable for low volume applications.
Clinical Centrifuges Is Used For The Separation Of Serum, Plasma, Urea, Blood Samples And Other Routine Applications In Hospital And Research Laboratories.
Price: $3499.00; Manufacturer: Thermo Scientific; Item ID: 6004886; Warranty: 30-Day Money-Back Guarantee; Description: Includes TX-750 swinging bucket rotor.
A blood component separating device comprises a centrifuge bowl adapted for rotation about its axis in a centrifuge. The bowl defines an outer circumferential wall plus an inner circumferential wall, spaced from the outer wall, to define a circumferential slot adapted for receiving blood components. Access tubing is adapted for communication with the slot. Preferably, an elongated, flexible, collapsible inner liner is provided in the slot. Individual access tubing also may communicate with an elongated container interior between the ends of the elongated, collapsible container. Furthermore, a portion of the slot may define the shape of an outwardly extending spiral, to provide an increasing gravitational field upon fluids therein as the fluid moves along the slot.
Yes. The QIAcube centrifuge can be operated independently if the QIAcube is not performing a protocol run. For instructions on how to operate the centrifuge, refer to the QIAcube User Manual, chapter 5 Operating Procedures, section 5.8 Operating the Centrifuge.. ...
80 x Microlitre 0.2-2ml 24 x Blood tube 4-7mm (13mm) 16 x Blood tube 7-10ml (16mm) 8 x Conical 15ml 4 x Conical 50ml 4 x Universal 25ml ...
Beckman J6B Centrifuge that we supply at Block Scientific is a high capacity refrigerated floor centrifuge, perfect for routine clinical applications.
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MANN+HUMMEL has developed a centrifugal oil cleaner focused on the separation of soot from oil. The basic setup and operation principle of a free jet driven centrifugal oil cleaner and its integration into an engine oil system will be explained.The development was supported by a new simulation tool, which predicts the centrifugal cleaner performance using computer analysis. This includes both the prediction of rotor speed and particle separation.Additionally, MANN+HUMMEL performed a detailed rotor design analysis in order to reduce torque resistance, to improve environmental protection and reduce cost ...
This independent 126 pages report guarantees you will remain better informed than your competition. With over 170 tables and figures examining the Centrifugal Chiller market, the report gives you a visual, one-stop breakdown of the leading products, submarkets and market leaders market revenue forecasts as well as analysis to 2025.. The report provides a basic overview of the Centrifugal Chiller industry including definitions, classifications, applications and industry chain structure. And development policies and plans are discussed as well as manufacturing processes and cost structures.. Primary sources are mainly industry experts from core and related industries, and suppliers, manufacturers, distributors, service providers, and organizations related to all segments of the industrys supply chain. The bottom-up approach was used to estimate the Global market size of Centrifugal Chiller Market based on end-use industry and region, in terms of value. With the validation of data through primary ...
These studies document an important role for Tyr348 of the α1B-AR in agonist binding, in functional coupling to PI hydrolysis and Ca2+ mobilization, and in agonist-induced internalization of the receptor. Mutation of Tyr348 to alanine increased agonist binding affinity by ∼10-fold, without altering antagonist binding. This mutation also essentially completely eliminated agonist-induced stimulation of PI hydrolysis and elevation of intracellular Ca2+. Agonist-induced conversion of receptors to a form that is inaccessible to the lipophilic radioligand [3H]prazosin in intact cell binding assays on ice occurred to a similar or greater extent for the Y348A receptor as for the wild-type receptor. In contrast, agonist-induced redistribution of receptors from the plasma membrane fraction to the light vesicle fraction in sucrose density gradient centrifugation assays occurred for the wild-type receptor but not for the Y348A receptor.. Two important conclusions regarding α1B-AR internalization follow ...
QIAprep Spin Miniprep 1. Resuspend pelleted bacterial cells in 250ul Buffer P1 an transfer to microcentrifuge tube (Ensure RNase A has been added to Buffer P1 2. Add 250ul Buffer P2 and mix thoroughly by inverting the tube 4-6 times until solution is viscous and slightly clear. Do not vortex as doing so will shear the DNA 3. Add 350ul Buffer N3 and mix the solution thorougly by inverting the tube 4-6 times. Solution should become cloudy 4. Centrifuge for 10min. at 13000rpm (~17900 x g) 5. Apply the supernatants from step 4 to the QIAprep spin column 6. Centrifuge for 30-60sec. Discard flowthrough 7. Wash QIAprep spin column by adding 0.75ml Buffer PE (w/EtOH) and centrifuge for 30-60sec. Discard flowthrough 8. Centrifuge an additional 1min. to remove residual wash buffer 9. Place QIAprep column in a clean 1.5ml microcentrifuge tube. Add 50ul dH2O to the center of each QIAprep, let stand for 1min. and centrifuge for 1min ...
QIAprep Spin Miniprep 1. Resuspend pelleted bacterial cells in 250ul Buffer P1 an transfer to microcentrifuge tube (Ensure RNase A has been added to Buffer P1 2. Add 250ul Buffer P2 and mix thoroughly by inverting the tube 4-6 times until solution is viscous and slightly clear. Do not vortex as doing so will shear the DNA 3. Add 350ul Buffer N3 and mix the solution thorougly by inverting the tube 4-6 times. Solution should become cloudy 4. Centrifuge for 10min. at 13000rpm (~17900 x g) 5. Apply the supernatants from step 4 to the QIAprep spin column 6. Centrifuge for 30-60sec. Discard flowthrough 7. Wash QIAprep spin column by adding 0.75ml Buffer PE (w/EtOH) and centrifuge for 30-60sec. Discard flowthrough 8. Centrifuge an additional 1min. to remove residual wash buffer 9. Place QIAprep column in a clean 1.5ml microcentrifuge tube. Add 50ul dH2O to the center of each QIAprep, let stand for 1min. and centrifuge for 1min ...
A photometric liquid analysis apparatus of the centrifugal analysis type uses insert elements having an elongated body, an optical measurement chamber near one end of the elongated body and a positioning trough on one side of the elongated body. The photometric liquid analysis apparatus has a rotor for rotating the insert elements to photometric means for photometric analysis of a liquid then in the optical measurement chamber of the insert element during the rotation of the rotor. The rotor has radial guiding chambers, each having an opening at an end thereof adjacent the outer periphery of the rotor and a configuration for receiving one of the insert elements with its positioning trough on a lateral side thereof and adjacent the outer periphery of the rotor. A fixed element on the rotor is on a lateral side of each guiding chamber circumferentially spaced from the positioning trough of the insert element therein when the insert element is initially received in the guiding chamber and an adjustment
In article ,33D36EB8.68AA at sciborg.uwaterloo.ca,, Wildwind ,swvong at sciborg.uwaterloo.ca, wrote: , Hello, , , I have extracted protein for 1-D electrophoresis in plant tissue and , have had no problems in the past. However, recently (in seed tissue) I , have had severe streaking throughout the entire gels (not just in the , lanes) following staining, making detection of bands impossible. I asked , several co-workers who believe it may be polysaccharides in the sample , buffer. Does anyone have any suggestions on how to fix this problem? It , would be appreciated. , , Thanks I would agree on the polysaccaride theory. If you´re working with the membrane fraction, make a centrifugation an resuspend only the top of the pellet leaving the whitish lower pellet. Sometimes you have to repeat this washing step. It helps if you use the second step a small bore tube. If you are working with the soluble fraction just make a high speed centrifugation, that should do it. Hope that helps Thomas -- Thomas ...
Whisper quiet operation. The CLS-1610 is the first and only compact microcentrifuge capable of achieving centrifugal speeds up to the critical threshold of 16,000 xg, often held as the standard for many molecular biology/DNA protocols. Its brushless, maintenance free drive system makes it powerful, yet compact enough to allow each work station to be fully equipped with a personal centrifuge.. CLS-1610 defines a new class of microcentrifuge: compact, quick, powerful and affordable. All aspects of microcentrifuge performance were taken into consideration and no compromises were made. In addition to its unsurpassed speed, the CLS-1610 also delivers shortened acceleration/deceleration times, whisper quiet operation and its computer-designed airflow pattern minimizes sample temperature increases during longer runs at high speeds.. All operating parameters are set using a single, conveniently located control knob and the large, bright LCD provides a clear indication of time and rpm or g-force. A ...
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Concentration gradients are often used in separations based on chromatographic, electrophoretic and centrifugal methods. In this report, a BASIC computer program for calculating and graphically representing gradients is described. This GRADIENT program is intended to be run on IBM-compatible computers ...
Centrifuge benchtop Centurion Scientific PrO-Research K243R for general purpose, low, medium and high capacity cell culture applications, minimum tube size 0.2ml, maximum tube size 750ml, maximum g force 22000, min temperature -9°C, max temperature 40°C, run counter, no rotor included
Centrifuge benchtop Centurion Scientific PrO-Research K242R for general purpose, low, medium and high capacity cell culture applications, minimum tube size 0.2ml, maximum tube size 500ml, maximum g force 22000, min temperature -9°C, max temperature 40°C, run counter, no rotor included
[152 Pages Report] Laboratory Centrifuge Market Report categorizes the global Market by Application (Microbiology/Proteomics/Genomics/Diagnostic), Product (Equipment (Microcentrifuge/Ultracentrifuge), Accessories), End User (Pharmaceutical/Hospital/Biotech), Intended Use, Rotor Design & Geography
I store all my media etc at 4C and then warm to room temperature or 37C, I always centrifuge at 4C and at a maximum speed of 1000rpm for 5 mins. This was how I was taught 10 years ago and as I far as I understand it, it helps preserve the cells better- like putting things on ice, any damage from DMSO or other things is slowed at the the lower temperatures. It seems from these replies that maybe it doesnt make a huge difference though.. ...
HemataStat II is a microhematocrit centrifuge that provides a quantitative hematocrit reading for up to six blood samples from one 60 second spin. Ideal for point-of care and laboratory use in clinics and hospitals. Its compact size and the optional battery pack makes it well suited for outreach programs and also for veterinary settings.
Frontier Micro are benchtop micro centrifuges that provide high-speed operation for a number of essential lab applications, including DNA/RNA preparation.
The laboratory centrifuge market is expected to reach USD 1.74 Billion by 2020 from USD 1.53 Billion in 2015, growing at a CAGR of 2.5% from 2015 to 2020
Centrifuges use high rotational speeds to separate different materials according to their densities. These devices are common in laboratories, dairy
Drucker Diagnostics QBC capillary centrifuge system is now available at our online store; 42474009 ultra-compact system for sale. Check it out now!
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Global Centrifugal Engine-Driven Pumps Market Report 2017 is a professional and deep research report in this field. For overview analysis, the report introduces Centrifugal Engine-Driven Pumps basic information including definition, classification, application, industry chain structure, industry overview, policy analysis, and news analysis, etc. Global Centrifugal Engine-Driven Pumps Market Report 2017 is a professional and deep research report in this field. For overview analysis, the report introduces Centrifugal Engine-Driven Pumps basic information including definition, classification, application, industry chain structure, industry overview, policy analysis, and news analysis, etc.. For technical data and manufacturing plants analysis, the report analyzes Centrifugal Engine-Driven Pumps leading suppliers on capacity, commercial production date, manufacturing plants distribution, R&D status, technology sources, and raw materials sources.The Report important aspects like development Trends , ...
Download the transcript. Fraser: Astronomy Cast Episode 181 for Monday March 15, 2010, Rotation. Welcome to Astronomy Cast, our weekly facts-based journey through the cosmos, where we help you understand not only what we know, but how we know what we know. My name is Fraser Cain, Im the publisher of Universe Today, and with me is Dr. Pamela Gay, a professor at Southern Illinois University Edwardsville. Hi Pamela, howre you doing?. Pamela: Im doing well. How are you doing?. Fraser: Excellent, as usual. Alright, so everything in the universe is spinning. In fact, without this rotation, life on Earth wouldnt even exist. We need the conservation of angular momentum to flatten out galaxies and solar systems, and to make planets possible. Lets find out about the physics involved in everything that spins and finally figure out the difference between centripetal and centrifugal force. Man, there is nothing that makes physics geeks madder than to misuse centrifugal and centripetal force. Honestly, I ...
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Coupling of physical, biological and chemical processes associated with particle resuspension and seston flux was investigated at three sites in the North Sea with contrasting water column (mixed/stratified) and seabed (cohesive/non-cohesive) characteristics. Seston concentration was determined by a combination of local resuspension and advection of a regional horizontal concentration gradient. Model simulations of observations show that fair weather, the bed erosion rate was limited by the availability of suitable bed material. The resuspended particles were derived from a surficial veneer of material (fluff) that was relatively enriched in organic carbon. Sediment from the bed itself was therefore not resuspended by tidal currents even at a shallow water, sandy site. Bioturbation of the seabed by infauna significantly modified the properties of muddy sands at a deep water site in summer, but this was insufficient to cause tidal entrainment of the bed sediment. Resuspension increased under ...
The reactivity of five monoclonal antibodies J5, OKB-cALLA, Nu-N1, Nu-N2 and VIL-A1 against the common acute lymphoblastic leukaemia (common-ALL) antigen (glycoprotein 100, CD10); was investigated by indirect immunofluorescence in cell suspensions, and by immunoperoxidase in cytocentrifuge slides of ALL, chronic B cell lymphoproliferative disorders, and plasma cell dyscrasias. The five monoclonal antibodies gave similar positive results with both techniques only in samples of ALL. J5 was positive in variable degrees by immunofluorescence in the majority of B cell disorders examined but this was not confirmed by immunoperoxidase. OKB-cALLA reacted in a similar way to J5 in both techniques, although with a lower percentage of cells by immunofluorescence. Nu-N1, Nu-N2, and VIL-A1 were mainly negative when tested by both immunofluorescence and immunoperoxidase in B cell disorders other than ALL and therefore seemed to be more specific for the diagnosis of common-ALL.. ...
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Central centrifugal cicatricial alopecia (CCCA): Find the most comprehensive real-world symptom and treatment data on central centrifugal cicatricial alopecia (CCCA) at PatientsLikeMe. 25 patients with central centrifugal cicatricial alopecia (CCCA) experience fatigue, depressed mood, pain, anxious mood, and insomnia and use Doxycycline, Hydrocortisone topical, and Pimecrolimus to treat their central centrifugal cicatricial alopecia (CCCA) and its symptoms.
Centrifugation fluids. The high density of the caesium ion makes solutions of caesium chloride, caesium sulfate, and caesium ...
Centrifugation) অলাগতিয়াল দ্ৰব্যসমূহ আতৰোৱা হয়। (iv) বাকী থকা পৃষ্ঠপ্লৱখিনিত (Supernatant) প্ৰটিন, DNA আৰু RNA থাকে। (v) ...
Hinton H & Dobrota N 1978, 'Density gradient centrifugation', in TS Work & E Work (eds), Laboratory techniques in biochemistry ...
Other varieties are partially refined by centrifugation or by using a spray dryer. ...
Although not normally what first comes to mind, many forms of human-derived agriculture clearly fit the broad definition of "'utilizing a biotechnological system to make products". Indeed, the cultivation of plants may be viewed as the earliest biotechnological enterprise. Agriculture has been theorized to have become the dominant way of producing food since the Neolithic Revolution. Through early biotechnology, the earliest farmers selected and bred the best suited crops, having the highest yields, to produce enough food to support a growing population. As crops and fields became increasingly large and difficult to maintain, it was discovered that specific organisms and their by-products could effectively fertilize, restore nitrogen, and control pests. Throughout the history of agriculture, farmers have inadvertently altered the genetics of their crops through introducing them to new environments and breeding them with other plants - one of the first forms of biotechnology. These processes also ...
Two different kinds of genetic material exist: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Cells use DNA for their long-term information storage. The biological information contained in an organism is encoded in its DNA sequence.[4] RNA is used for information transport (e.g., mRNA) and enzymatic functions (e.g., ribosomal RNA). Transfer RNA (tRNA) molecules are used to add amino acids during protein translation. Prokaryotic genetic material is organized in a simple circular bacterial chromosome in the nucleoid region of the cytoplasm. Eukaryotic genetic material is divided into different,[4] linear molecules called chromosomes inside a discrete nucleus, usually with additional genetic material in some organelles like mitochondria and chloroplasts (see endosymbiotic theory). A human cell has genetic material contained in the cell nucleus (the nuclear genome) and in the mitochondria (the mitochondrial genome). In humans the nuclear genome is divided into 46 linear DNA molecules called ...
Another applicable technique is cofractionation in sucrose (or other material) gradients using isopycnic centrifugation.[49] ...
The name "white blood cell" derives from the physical appearance of a blood sample after centrifugation. White cells are found ...
CBM 588 for clinical use is produced by submerged anaerobic fermentation followed by centrifugation, drying, blending and ...
After collection, the whole blood is separated into red cells and plasma by centrifugation. A preservative solution is mixed ...
... via centrifugation) into its components, with red blood cells (RBC) in solution being the most commonly used product. Units of ...
Mechanical methods of acceleration, including vibration, centrifugation, and agitation, can also be used.[citation needed] ... centrifugation, and rheology. Each method has advantages and disadvantages.[14] ...
... s can be obtained from whole blood by centrifugation, which separates the cells from the blood plasma in a ...
... which includes enzymatic environments and centrifugation, cells that are better adapted to survive in culture are selected, ...
... and dried via centrifugation, it is scanned using fluorescence microscopy, and the pattern of peptide spots with bound ...
... and removing the insoluble fraction by filtration and centrifugation. Other methods may be used to remove pigments and sugars. ...
... centrifugation, and vibration.[21] Centrifugation recreates Earth's gravitational force on the space station, in order to ... Centrifugation can be performed with centrifuges or by cycling along the inner wall of the space station.[20] Whole body ...
By glycerol gradient centrifugation.[43]. *By a DNA column.. *By an ion chromatography column.[44] ...
... or by centrifugation of live ants [184] followed by silica-gel chromatography purification.[185] Tracking and dosing the ... "Gas-chromatography and UV-spectroscopy of Hymenoptera venoms obtained by trivial centrifugation". Data in Brief. 18: 992-998. ...
The paste is then pressed by centrifugation/ the water is thereafter separated from the oil in a second centrifugation as ... or centrifugation (modern method). After extraction the remnant solid substance, called pomace, still contains a small quantity ... This very slow separation process has been replaced by centrifugation, which is much faster and more thorough. The centrifuges ...
Collected blood is then separated into blood components by centrifugation: red blood cells, plasma, platelets, albumin protein ...
Graphene is separated from graphite by centrifugation,[13] producing graphene concentrations initially up to 0.01 mg/mL in N- ...
Discontinuous flow centrifugation: One venous catheter line is required. Typically, a 300 ml batch of blood is removed at a ... Continuous flow centrifugation: Two venous lines are used. This method requires slightly less blood volume out of the body at ...
This mass is collected by centrifugation, then transported through several stages integrated in a continuous process. About 65 ...
... centrifugation at isolating the desired blood component. ...
... by removing the fat using heat and centrifugation, then treating it with ammonia to kill E. coli. The process was deemed ...
The bacterial cells were harvested by centrifugation (8000 × g for 10 min) and re-suspended in sterile phosphate-buffered ...
... using buccal cell washing procedures that often include repetitive centrifugation, (e) applying diverse stains and microscopy ...
A) Example of sperm selection by density gradient centrifugation (DGC): Semen is placed on top a gradient of colloid (e.g., ... 2000). The use of two density gradient centrifugation techniques and the swim-up method to separate spermatozoa with chromatin ... Tavalaee, M., Deemeh, M. R., Arbabian, M., and Nasr-Esfahani, M. H. (2012). Density gradient centrifugation before or after ... A recent study on bull sperm reported that within two different sperm populations separated by density gradient centrifugation ...
After centrifugation, the sample separates into 3 phases: an upper, colorless, aqueous phase containing RNA; a white interphase ...
PBMCs were isolated by density gradient centrifugation using Histopaque-1077 (Sigma-Aldrich). After isolation, the cells were ...
After centrifugation (3,000 rpm for 3 minutes) at ambient temperature, 50 μL of supernatant was transferred to a clean 96-well ...
After a 15-min incubation with aeration at 37°, cells were harvested by centrifugation and resuspended in the same growth ...
... centrifugation and resuspension) and nonionic detergents. Organisms with disrupted outer membranes were markedly more antigenic ...
Pressurization, centrifugation or both - with Vivacell ultrafiltration systems. *Secure and ultrafast concentration through ...
Total cellular RNA was isolated by lysis of cells in guanidinium isothiocyanate and centrifugation through a CsCl pad. Poly(A ...
The data were subjected to analysis of variance at a level of significance of 5%. Percoll centrifugation reduced the percentage ... Acrosome/pathology , Animals , Cattle/physiology , Cell Membrane/pathology , Cell Separation/veterinary , Centrifugation, ... Transmission electron microscopy for characterization of acrosomal damage after Percoll gradient centrifugation of ... Percoll centrifugation. The evaluation of 20 sperm heads from each of the 36 samples analyzed ensured that a large number of ...
The monocytes were separated by centrifugation and cultivated in CultilabÒ medium. Supernatant samples of 100μl from the ...
Supernatants from infected cells were collected and clarified by centrifugation. Plaque assay in Vero (CCL-81) cells was used ...
Comparative analyses of PrP(Sc) pellets prepared by high-speed centrifugation revealed that about 90% PrP(Sc) released into ...
Rats were sacrificed 3 days after exposure, and pulmonary microsomes were isolated by differential centrifugation of lung ...
The boiled bacterial lysate was rapidly cooled on ice for 5 minutes followed by centrifugation for 5 minutes at 16 000. g. . ... followed by brief centrifugation at 2500. g. for 10 minutes. This supernatant was used in the PCR assays. Primer nucleotide ...
MK requires a centrifuge and it has been recommended in the literature that centrifugation should be performed one day to three ...
... sensitive enough to investigate the levels of thiocyanate in the saliva samples of smokers and non-smokers with centrifugation ...
A urine specimen was collected, concentrated by centrifugation, and examined microscopically.. More ...
The splenocytes were then pelleted by centrifugation for 5 minutes. The pellet was resuspended and centrifuged at 2,000 ...
Zonal Centrifugation use Centrifugation, Zonal Zonal Centrifugations use Centrifugation, Zonal Zonalon use Doxepin ...
The microsomal membranes isolated by sucrose density gradient centrifugation from developing toad ovary have been found to ...
After centrifugation, the supernatant was discarded and fresh medium was added to the cells. The cells were incubated overnight ... RT-PCR.Virus from 100 ml of HYB PRO BMDC supernatant was passed through a 0.22-μm filter and concentrated by centrifugation for ... Primary cell cultures.Total splenocytes were enriched for mononuclear cells by density gradient centrifugation over Ficoll ( ... Virus was concentrated from cell supernatants by centrifugation at 105,000 × g for 1 h on a 30% sucrose cushion in phosphate- ...
  • To increase elution of large plasmid DNA, we recommend pre-warming the ZymoPURE Elution Buffer (50 ºC) and increasing the incubation time on column up to 10 minutes prior to centrifugation. (zymoresearch.com)
  • After centrifugation using a swing bucket rotor with a plate adaptor, you can remove the liquid by using a pipette. (biolegend.com)
  • The Axygen Axyspin Plate Spinner is the first centrifuge designed specifically for quick and easy centrifugation of samples in PCR plates or microplates. (thomassci.com)
  • Adsorption apheresis devices separate the blood through membrane technology or via centrifugation technology, all the blood component such as plasma and others are separated. (factmr.com)
  • The centrifugation time of three different nanoparticles was examined by calculating the time when the nanoparticles left the microchamber for the first time. (elsevier.com)
  • On the basis of a comparison of the centrifugation time of two different nanoparticle populations of 300 and 700nm in diameter, we propose that nanoparticles of different sizes can be physically separated by time under a range of inlet volume flow rates. (elsevier.com)
  • The size, composition, and surface structure of Oligotex particles have been optimized for uniform dispersion and minimal centrifugation time. (qiagen.com)