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.Centrifugation, Density Gradient: Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Centrifugation: Process of using a rotating machine to generate centrifugal force to separate substances of different densities, remove moisture, or simulate gravitational effects. It employs a large motor-driven apparatus with a long arm, at the end of which human and animal subjects, biological specimens, or equipment can be revolved and rotated at various speeds to study gravitational effects. (From Websters, 10th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Centrifugation, Zonal: Centrifugation using a rotating chamber of large capacity in which to separate cell organelles by density-gradient centrifugation. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Cell Fractionation: Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.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.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.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.Molecular Weight: The sum of the weight of all the atoms in a molecule.TritiumDiatrizoate: A commonly used x-ray contrast medium. As DIATRIZOATE MEGLUMINE and as Diatrizoate sodium, it is used for gastrointestinal studies, angiography, and urography.Sucrose: A nonreducing disaccharide composed of GLUCOSE and FRUCTOSE linked via their anomeric carbons. It is obtained commercially from SUGARCANE, sugar beet (BETA VULGARIS), and other plants and used extensively as a food and a sweetener.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)Acid Phosphatase: An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC 3.1.3.2.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)Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Organoids: An organization of cells into an organ-like structure. Organoids can be generated in culture. They are also found in certain neoplasms.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)Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Nucleotidases: A class of enzymes that catalyze the conversion of a nucleotide and water to a nucleoside and orthophosphate. EC 3.1.3.-.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.Cell SeparationMethods: A series of steps taken in order to conduct research.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.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.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.Membranes: Thin layers of tissue which cover parts of the body, separate adjacent cavities, or connect adjacent structures.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.Cytoplasmic Granules: Condensed areas of cellular material that may be bounded by a membrane.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.ThymidineMicrobodies: Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.GlucuronidaseCarbon 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.Nucleoproteins: Proteins conjugated with nucleic acids.Kinetics: The rate dynamics in chemical or physical systems.UridineElectron 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.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.Hexosaminidases: Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.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.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.Cell Line: Established cell cultures that have the potential to propagate indefinitely.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.Cytochrome ReductasesMicrosomes: 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)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.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.Monoamine Oxidase: An enzyme that catalyzes the oxidative deamination of naturally occurring monoamines. It is a flavin-containing enzyme that is localized in mitochondrial membranes, whether in nerve terminals, the liver, or other organs. Monoamine oxidase is important in regulating the metabolic degradation of catecholamines and serotonin in neural or target tissues. Hepatic monoamine oxidase has a crucial defensive role in inactivating circulating monoamines or those, such as tyramine, that originate in the gut and are absorbed into the portal circulation. (From Goodman and Gilman's, The Pharmacological Basis of Therapeutics, 8th ed, p415) EC 1.4.3.4.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).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)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.Chlorides: Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.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.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.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)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.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.Muramidase: A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC 3.2.1.17.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.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.Laryngeal Neoplasms: Cancers or tumors of the LARYNX or any of its parts: the GLOTTIS; EPIGLOTTIS; LARYNGEAL CARTILAGES; LARYNGEAL MUSCLES; and VOCAL CORDS.Filtration: A process of separating particulate matter from a fluid, such as air or a liquid, by passing the fluid carrier through a medium that will not pass the particulates. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)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)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)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.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)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.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.Cathepsins: A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.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.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)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).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.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.Proteoglycans: Glycoproteins which have a very high polysaccharide content.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.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)Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.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)Viral Proteins: Proteins found in any species of virus.Catalase: An oxidoreductase that catalyzes the conversion of HYDROGEN PEROXIDE to water and oxygen. It is present in many animal cells. A deficiency of this enzyme results in ACATALASIA.Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.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)DNA Replication: The process by which a DNA molecule is duplicated.Time Factors: Elements of limited time intervals, contributing to particular results or situations.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Apolipoproteins: Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.Bacterial Proteins: Proteins found in any species of bacterium.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.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.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.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.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.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Virus Replication: The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.Lipoproteins: Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.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.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.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)Triiodobenzoic Acids: Triiodo-substituted derivatives of BENZOIC ACID.

Purification of gibberellic acid-induced lysosomes from wheat aleurone cells. (1/213)

Using isopycnic density gradient centrifugation, lysosomes were concentrated in a single region of a sucrose-Ficoll gradient (p = 1-10 g cm-3), well separated from most other cell organelles. Gibberellic acid-induced lysosomes were found to be rich in alpha-amylase and protease but not ribonuclease. The lysosomal band also contained a majority of the NADH2-cytochrome c reductase, a marker enzyme for endoplasmic reticulum, found in the gradient. Examination of electron micrographs revealed that a purified band of lyosomes contained at least 3 vesicle types, ranging in size from 0-1 to 0-5 mum. The significance of these findings to proposed mechanisms of action of gibberellic acid is discussed.  (+info)

Lectins as membrane components of mitochondria from Ricinus communis. (2/213)

1. Mitochondria were isolated from developing endosperm of Ricinus communis and were fractionated into outer membrane and inner membrane. The relative purity of the two membrane fractions was determined by marker enzymes. The fractions were also examined by negative-stain electron microscopy. 2. Membrane fractions were sequentially extracted in the following way. (a) Suspension in 0.5M-potassium phosphate, pH7.1; (b)suspension in 0.1M-EDTA (disodium salt)/0.05M-potassium phosphate, pH7.1; (c) sonication in 0.05M-potassium phosphate, pH7.1;(d)sonication in aq. Triton X-100 (0.1%). The membranes were pelleted by centrifugation at 100 000g for 15 min, between each step. Agglutination activity in the extracts was investigated by using trypsin-treated rabbit erythrocytes. 3. The addition of lactose to inner mitochondrial membrane resulted in the solubilization of part of the lectin activity, indicating that the protein was attached to the membrane via its carbohydrate-binding site. Pretreatment of the membranes with lactose before tha usual extraction procedure showed that lactose could extract lectins that normally required more harsh treatment of the membrane for solubilization. 4. Lectins extracted from inner membranes were purified by affinity chromatography on agarose gel. Polyacrylamide-gel electrophoresis of purified samples in sodium dodecyl sulphate indicated that at least part of the lectin present in inner mitochondrial membrane was identical with the R. communis agglutinin of mol.wt. 120 000.  (+info)

Transduction-like gene transfer in the methanogen Methanococcus voltae. (3/213)

Strain PS of Methanococcus voltae (a methanogenic, anaerobic archaebacterium) was shown to generate spontaneously 4.4-kbp chromosomal DNA fragments that are fully protected from DNase and that, upon contact with a cell, transform it genetically. This activity, here called VTA (voltae transfer agent), affects all markers tested: three different auxotrophies (histidine, purine, and cobalamin) and resistance to BES (2-bromoethanesulfonate, an inhibitor of methanogenesis). VTA was most effectively prepared by culture filtration. This process disrupted a fraction of the M. voltae cells (which have only an S-layer covering their cytoplasmic membrane). VTA was rapidly inactivated upon storage. VTA particles were present in cultures at concentrations of approximately two per cell. Gene transfer activity varied from a minimum of 2 x 10(-5) (BES resistance) to a maximum of 10(-3) (histidine independence) per donor cell. Very little VTA was found free in culture supernatants. The phenomenon is functionally similar to generalized transduction, but there is no evidence, for the time being, of intrinsically viral (i.e., containing a complete viral genome) particles. Consideration of VTA DNA size makes the existence of such viral particles unlikely. If they exist, they must be relatively few in number;perhaps they differ from VTA particles in size and other properties and thus escaped detection. Digestion of VTA DNA with the AluI restriction enzyme suggests that it is a random sample of the bacterial DNA, except for a 0.9-kbp sequence which is amplified relative to the rest of the bacterial chromosome. A VTA-sized DNA fraction was demonstrated in a few other isolates of M. voltae.  (+info)

Detection of serum proteins in the electrophoretic patterns of total proteins of mycoplasma cells. (4/213)

The contamination of mycoplasma cell preparations by serum proteins originating from culture medium was studied. A. laidlawii and M. arthritidis cells were grown in the presence of [14C]-aminoacids, and the cells were washed with 0-9% NaC1 by threefold centrifugation. Total proteins of the washed cells were analysed by SDS gel electrophoresis. Coomassie-stained electrophoretic patterns were compared with autoradiographs of the same gels. The stained electrophoretic pattern of washed A. laidlawii grown without serum was identical with autoradiographs of the same cells grown without or with serum. That of washed A. laidlawii grown with serum differed from the corresponding autoradiography by the presence of extra protein bands I, II, III, and IV with molecular weights of over 160,000, 80,000-87,000, 55,000 and 25,000, respectively. The same extra bands were found in stained electrophoretic patterns of washed: (a) A. laidlawii cells grown without serum and mixed with serum in the stationary phase, (b) M. arthritidis cells, as compared with their autoradiographs, (c) serum precipitate. The bands III and IV may be due to the heavy and light chains of gamma-globulin, the band II might belong to transferrin or to some component of complement. Acidification of serum to pH 5 brought about 100-fold rise of amount of serum precipitate, the number of bands in the electrophoretic pattern of the precipitate being also increased. Stained electrophoretic patterns of cells purified by twofold centrifugation in step sucrose density gradient (1-20-1-27 g./cm.3 for A. laidlawii, and 1-15-1-25 for M. arthritidis) contained no extra bands and matched completely with their autoradiographs. It was concluded that contamination of washed mycoplasma cells by serum proteins is mainly due to co-precipitation of aggregated serum proteins together with cells during centrifugation rather than to adsorption of serum proteins on the cell surface.  (+info)

A study of the intracellular and secreted forms of the MUC2 mucin from the PC/AA intestinal cell line. (5/213)

In this study we present data on the entire population of MUC2 molecules secreted from and within the cell layer of an intestinal cell line. The molecular size distribution of the extracted molecules and their reactivity with two different MUC2 polypeptide antibodies indicated the presence of precursor and mature forms of the mucin. Oligomerized forms of the mucin were found in both the cell layer and medium; however, precursor forms were confined to the cell layer. Isopycnic density gradient centrifugation gave good resolution of mature and precursor forms of MUC2 as assessed by agarose gel electrophoresis. Three different populations of MUC2 were identified: one at low density (>1.3 g/ml) containing the N-glycosylated, non-O-glycosylated polypeptide; a second at intermediate density (1.3-1.35 g/ml) which may represent partially O-glycosylated intermediates; and a third at high density (1.36-1.48 g/ml) containing the mature MUC2 mucins. Rate-zonal centrifugation and agarose electrophoretic analysis of the low-density fraction indicated that the N-glycosylated MUC2 polypeptide was present as putative monomer and dimer/oligomer species. The combination of isopycnic density gradient centrifugation with agarose electrophoresis provides a new and simple approach that allows us to follow the MUC2 gene product from polypeptide through to the mature glycosylated mucin.  (+info)

Isopycnic sedimentation of DNA in metrizamide: the effect of low concentrations of ions on buoyant density and hydration. (6/213)

Metrizamide, an inert, non-ionic organic compound, dissolves in water to give a dense solution in which DNA bands isopycnically at a density corresponding to that of fully hydrated DNA. Density-gradient centrifugation in solutions of metrizamide has been used to determine the effects of very dilute solutions of salts on the buoyant density of native and denatured DNA. It has been shown that the buoyant density of DNA is dependent on both the counter-cation and the anion present. Interpretation of the data in terms of the degree of hydration of the macromolecule indicates that (i), NaDNA is more highly hydrated than CsDNA; and (ii), the hydration of NaDNA varies with anion in the order sulphate< fluoride< chloride< bromide< iodide. It is suggested that isopycnic centrifugation in metrizamide is a simple method for determining the effects of salts (and other small molecules) on the hydration of nucleic acids under conditions of high ratios of salt to DNA (> 5 x 10(3) moles/mole) while high (0.999) water activity is maintained.  (+info)

Fractionation and characterization of satellite DNAs of the kangaroo rat (Dipodomys ordii). (7/213)

Nuclear DNA from liver cells of the kangaroo rat species Dipodomysordii was fractionated and characterized with the aid of buoyant density gradients in neutral and alkaline CsCl and in Ag(+)-Cs(2)SO(4). More than one-half of the DNA was present in three density satellites, a greater proportion than in any other species yet reported; the purified satellite DNAs were denser than principal DNA. All satellite fractions revealed sharp isopycnic bands and narrow denaturation profiles. Two had identical buoyant densities but differed substantially in T(m), base composition, and reassociation kinetics. In alkaline CsCl all three satellites, as well as a shoulder of intermediate repetitive DNA on the heavy side of the principal band, revealed unique strand densities. The most highly repetitive satellite was unusually rich in (G + C) and contained 6.7% of 5-methylcytosine. A survey of internal organs and spermatozoa of an adult male revealed no significant differences in distribution of the satellites among tissues.  (+info)

Human immunodeficiency virus type 1 virion density is not determined by nucleocapsid basic residues. (8/213)

The human immunodeficiency virus type 1 (HIV-1) Gag polyprotein is sufficient for assembly and release of virion-like particles from the plasma membrane. To promote assembly, the Gag polyprotein must polymerize to form a shell that lines the inner membrane of nascent virions. Several techniques have been used to functionally map the domain required for Gag polymerization (the I domain). Among these methods, isopycnic centrifugation has been used under the assumption that changes in virion density reflect impairment in Gag-Gag interaction. If virion density is determined by efficient Gag-Gag interaction, then mutation of basic residues in the nucleocapsid (NC) domain should disrupt virion density, since these residues constitute the I domain. However, we have previously shown that simultaneous disruption of up to 10 HIV-1 NC basic residues has no obvious effect on virion density. To rule out the possibility that HIV-1 NC basic residues other than those previously mutated might be important for virion density, mutations were introduced at the remaining sites and the ability of these mutations to affect Gag-Gag interaction and virion density was analyzed. Included in our analysis is a mutant in which all NC basic residues are replaced with alanine. Our results show that disruption of HIV-1 NC basic residues has an enormous effect on Gag-Gag interaction but only a minimal effect on the density of those virions that are still produced. Therefore, the determinants of the I domain and of virion density are genetically distinguishable.  (+info)

Looking for Centrifugation, isopycnic? Find out information about Centrifugation, isopycnic. A line on a chart connecting all points of equal or constant density. Of equal or constant density, with respect to either space or time Explanation of Centrifugation, isopycnic
CHINA CHIC Germanier distilled elements of Mongolian patchwork, the traditional Chinese qipao, and Shanghai Tangs own history to create the assertive, modernist pieces, which he rendered bolder
The intracellular localization of alkaline phosphatase has been determined in human neutrophils with analytical subcellular fractionation by density gradient centrifugation and EM cytochemistry. Centrifugation on sucrose gradients containing 1 mM DETA and 5 units/ml of heparin showed that alkaline phosphatase was associated with a membranous component distinct from plasma membrane, mitochondria, specific granules and azurophil granules. There was no resolution from the endoplasmic reticulum. Density gradient centrifugation on a sucrose-imidazole-heparin gradient showed a clear resolution of the alkaline phosphatase-containing membranes from the Golgi and endoplasmic reticulum. Density gradient centrifugation of neutrophils that had been disrupted in the presenceof 0.12 mmol/l. digitonin clearly separated alkaline phosphatase-containing membranes from the endoplasmic reticulum. Part of the gamma-glutamyl transferase has a similar localization to that of alkaline phosphatase. EM cytochemistry of ...
ADPase (adenosine diphosphatase) was assayed in rat liver homogenates with [beta-32P]ADP as substrate. The activity had a pH optimum of 8.0 and was strongly activated by Mg2+. The intracellular localization was determined by analytical subcellular fractionation with single-step sucrose-density-gradient centrifugation. Selective membrane perturbants were used to enhance the resolution of the various organelles. ADPase was localized to the mitochondria. Mitochondria were isolated by differential centrifugation and subfractionated by selective disruption of the inner and outer membranes. The intramitochondrial localization of ADPase was compared with various marker enzymes and was shown to be concentrated in the outer-membrane fractions. The effects of various inhibitors on the ADPase activity were determined and the possibility that the activity could be due to known enzyme systems was considered. It is concluded that ADP degradation is due to a hitherto unrecognized mitochondrial enzyme. ...
1. Lettrée cells were grown intraperitoneally in MF-1 mice and labelled extrinsically by the 125I/lactoperoxidase technique. 2. The cells were swollen in 1 mM-NaHCO3 and disrupted in a Dounce homogenizer. 3. Crude fractions of endoplasmic reticulum, plasma membrane and mitochondria were separated from a post-nuclear supernatant by sedimentation-rate gradient centrifugation in a BXIV zonal rotor. 4. Further resolution of these membranes was carried out in isopycnic sucrose gradients. 5. Bands of material from the latter were subfractionated in gradients of metrizamide. Some very pure subfractions of plasma membrane and endoplasmic reticulum were obtained. In addition, one subfraction containing 125I and NADPH-cytochrome c reductase but no Na++K+-stimulated adenosine triphosphatase and another containing these two enzymes but no 125I were resolved. ...
ABSTRACT: A new isopycnic separation technique was developed to minimize the effect of sediment granulometry on extraction efficiency of benthic meiofauna. The method uses colloidal silica Ludox® (DuPont) HS 40 as a high density solution to extract meiofaunal organisms from sediment. Previous protocols using silica sols have had problems with physical interactions between the sediment and the specimens, causing large variations in extraction efficiencies between sediment types. The procedure presented herein reduces this problem by the addition of a 5 min period of fluidization of the sediment. The time used to complete the method is minimized with a final centrifugation step, which accelerates the settling rate of the fine sediment, resulting in a total time required for separation of approximately 20 min. Forty-eight samples were processed, with sediments ranging from sand to silty clay. The average extraction efficiency was 96.8 ± 3.9% for the total meiofaunal abundance. Extraction ...
High-density lipoprotein (HDL) has previously been shown to promote angiogenesis. However, the mechanisms by which HDL enhances the formation of blood vessels remain to be defined. To address this,...
University of Waikato RNA based stable isotope probing (SIP) facilitates the detection and identification of active members of microbial populations that are involved in the assimilation of an isotopically labeled compound. ¹⁵N-RNA-SIP is a new method that has been discussed in recent literature but has not yet been tested. Herein, we define the limitations to using ¹⁵N-labeled substrates for SIP and propose modifications to compensate for some of these shortcomings. We have used ¹⁵N-RNA-SIP as a tool for analysing mixed bacterial populations that use nitrogen substrates. After incubating mixed microbial communities with ¹⁵N-ammonium chloride or ¹⁵N₂ we assessed the fractionation resolution of ¹⁵N-RNA by isopycnic centrifugation in caesium trifluoroacetate (CsTFA) gradients. We found that the more isotopic label incorporated, the further the buoyant density (BD) separation between ¹⁵N- and ¹⁴N-RNA, however it was not possible to resolve the labeled from unlabeled RNA ...
SW 41 Ti Rotor Assembly; For use in instruments classified: HRS Major Applications: Rate-zonal and isopycnic centrifugation of viruses, rate-zonal centrifugation of RNA. Includes: Part No. Description SW 41 Ti Rotor 333790; Bucket ...
The density-distribution patterns of various enzymes and of labeled materials have been determined by isopycnic centrifugation in a sucrose-0.2 M KCl gradient on homogenates of lymphoid tissues from rats injected with Triton WR-1339, 14C-labeled dextran, 51Cr-labeled erythrocytes, and cortisol. The results confirm and extend the conclusion, derived from previous investigations on normal animals, that the lysosomes of lymphoid tissues form two and possibly three, distinct populations. The evidence indicates that the L19 population belongs to macrophages and the L15 group to lymphocytes. The L30 population appears to be associated with a special type of phagocyte with a high capacity for dextran storage. All three populations seem to contribute to the activities found in soluble form in homogenates of normal lymphoid tissues.. ...
Day, E D.; Mickey, D D.; Rigsbee, L C.; and Meier, H, "Zonal centrifugation and flotation-fractionation of msd mutant mouse brain." (1972). Subject Strain Bibliography 1972. 1757 ...
Tangier disease is a rare inherited disorder characterized by a severe reduction in the amount of high-density lipoprotein (HDL).
Karaniwang tinuturing na mabuting kolesterol para sa pagtulong sa pagbawas ng panganib ng stroke at atake sa puso, parehong mataas at mababang antas ng high-density na lipoprotein (HDL)
article{717e4ead-cda5-44a8-b015-aedee76d1de0, abstract = {Human embryonic skin fibroblasts were pretreated with transforming growth factor-beta (TGF-beta) for 6 h and then labeled with [35S]sulphate and [3H]leucine for 24 h. Radiolabeled proteoglycans from the culture medium and the cell layer were isolated and separated by isopycnic density-gradient centrifugation, followed by gel, ion-exchange and hydrophobic-interaction chromatography. The major proteoglycan species were examined by polyacrylamide gel electrophoresis in sodium dodecyl sulphate before and after enzymatic degradation of the polysaccharide chains. The results showed that TGF-beta increased the production of several different 35S-labelled proteoglycans. A large chondroitin/dermatan sulphate proteoglycan (with core proteins of approximately 400-500 kDa) increased 5-7-fold and a small dermatan sulphate proteoglycan (PG-S1, also termed biglycan, with a core protein of 43 kDa) increased 3-4-fold both in the medium and in the cell ...
Mitochondrial DNA (MtDNA) with a neutral buoyant density of 1.681 g/cm3 has been isolated from unfertilized eggs of Drosophila melanogaster. This DNA is a circular molecule with an average length of 5.3 µm; it reassociates with a low C0t1/2 after denaturation, and in alkaline isopycnic centrifugation it separates into strands differing in density by 0.005 g/cm3. MtDNA isolated from purified mitochondria of unfertilized eggs or from total larval DNA melts with three distinct thermal transitions. The three melting temperature values suggest that the molecule may have three regions differing in average base composition. DNA isolated from unfertilized eggs of D. melanogaster contains approximately equal amounts of MtDNA and another DNA with a buoyant density of 1.697 g/cm3, slightly less dense than main peak DNA. The possibility that the heavier DNA fraction consists of amplified ribosomal DNA was excluded by hybridization experiments, but otherwise nothing is known of its origin or function. ...
Genetically modified tomatoes created at UCLA produce 6F peptide that mimics the action of apoA-1, the chief protein in high-density lipoprotein (HDL).
High levels of high density lipoprotein (HDL), also known as the good cholesterol, are thought to protect against heart disease.
High Density Lipoproteins (HDL) Interrupt the Sphingosine Kinase Signaling Pathway: A possible Mechanism for Protection Against Atherosclerosis by ...
Isolated potato (Solanum tuberosum) tuber mitochondria purified by isopycnic centrifugation in density gradients of Percoll were found to be highly intact, to be devoid of extramitochondrial contaminations and to retain a high rate of O2 consumption. When suspended in a medium that avoided rupture of the outer membrane, intact purified mitochondria progressively lost their NAD+ content by passive diffusion. This led to a slow decrease of oxoglutarate-dependent O2 consumption by isolated mitochondria. Addition of NAD+ to the medium restored the initial State-3 rate of oxoglutarate oxidation. The rate of NAD+ accumulation in the matrix space was concentration-dependent, exhibited Michaelis-Menten kinetics and was strongly inhibited by the analogue N-4-azido-2-nitrophenyl-4-aminobutyryl-NAD+. ...
Chlorpropamide, an oral hypoglycemic agent, was tested for effects on excision repair and postreplication repair of ultraviolet (UV) damage of DNA in CHO-K1 cells. The technique used to measure excision repair involved isopycnic centrifugation of density- and isotopically-labeled DNA. Alkaline sucro …
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INDICATIONS Zocor is used for lowering high cholesterol and triglycerides in certain patients. It also increases high-density lipoprotein (HDL, "good") cholesterol levels. It is used along with an appropriate diet. It is used in certain patients to reduce the risk of heart attack, stroke, and death due to coronary heart disease. It is also used to reduce the need for medical procedures to open blocked blood vessels. It is also used in certain patients to reduce the risk of heart attack, stroke, blood vessel blockage, or chest pain caused by angina. Zocor is an HMG-CoA reductase inhibitor, also known as a "statin." It works by reducing the production of certain fatty substances in the body, including cholesterol.. INSTRUCTIONS Use Zocor as directed by your doctor.. ...
INDICATIONS Zocor is used for lowering high cholesterol and triglycerides in certain patients. It also increases high-density lipoprotein (HDL, "good") cholesterol levels. It is used along with an appropriate diet. It is used in certain patients to reduce the risk of heart attack, stroke, and death due to coronary heart disease. It is also used to reduce the need for medical procedures to open blocked blood vessels. It is also used in certain patients to reduce the risk of heart attack, stroke, blood vessel blockage, or chest pain caused by angina. Zocor is an HMG-CoA reductase inhibitor, also known as a "statin." It works by reducing the production of certain fatty substances in the body, including cholesterol.. INSTRUCTIONS Use Zocor as directed by your doctor.. ...
Lee Biosolutions is an international producer and supplier of high purity finished human proteins. Headquartered in St. Louis and founded in 2002, the biotechnology firm serves academic and scientific researchers as well as IVD manufacturers worldwide. Lee BioSolutions produces and processes the raw biomaterials used in drug discovery and development, laboratory equipment calibration, clinical diagnosis and product testing. These include Low Denisity Lipoprotein (LDL),High Denisity Lipoprotein (HDL), CkMB and Troponin, The company is ISO 9001:2008 certified, FDA registered and meets USDA guidelines. To learn more about Lee Biosolutions visit www.LeeBio.com or call 314-968-1091 ...
View Notes - ps_2 from CHEMICAL E 20.410j at MIT. DOWNSTREAM PROCESSING Problem Set #2 Problem 1 A key to understanding centrifugation is understanding the equations that describe it. One can
Define Buoyant density. Buoyant density synonyms, Buoyant density pronunciation, Buoyant density translation, English dictionary definition of Buoyant density. n. 1. a. The tendency or capacity to remain afloat in a liquid or rise in air or gas. b. The upward force that a fluid exerts on an object less dense than...
RESULTS NIDDM subjects had larger IMT, higher levels of triglycerides, and lower concentrations of high-density lipoprotein (HDL) cholesterol compared with control subjects. IMT was positively correlated to age and systolic blood pressure and inversely to HDL cholesterol in both groups. The prevalence of CA was 46% in NIDDM subjects and 18% in control subjects. In multiple regression analysis, IMT was the only variable significantly associated to CA.. ...
Morphologically, GSTP1−/− cells in growth-limiting conditions seemed to undergo marked cell death, with sporadic live cells that did not form colonies. To confirm morphologic apoptosis in the cells, we stained for pyknotic nuclei and calculated apoptotic indexes. We found no significant differences in apoptotic index in cells seeded at densities of 7.5 × 103 cells/cm2 ( Fig. 2B). However, starting with a lower seeding density of 2.0 × 103 cells/cm2, there was a 2-fold increase in the apoptotic index in GSTP1−/− cells compared with GSTP1+/+ cells, particularly after 8 days in culture. Furthermore, at the lowest seeding density of 0.5 × 103 cells/cm2, there was an up to 10-fold increase in the apoptotic index in GSTP1−/− cells compared with GSTP1+/+ cells.. Together, our findings show that GSTP1 is required for cell survival and proliferation in growth-limiting conditions. Notably, the differences in survival and growth at low-density seeding were not evident when the cells were ...
No. However, a second centrifugation step helps remove traces of buffy coat that may be accidentally transferred when aspirating plasma after the first centrifugation step. ...
Purpose : Terminally differentiated stratified epithelial cells maintain barrier function at the ocular surface through a specialized protective structure composed of highly O-glycosylated transmembrane mucins. Relatively low levels of N-glycans are found on transmembrane mucins, and their structure and function remains poorly characterized. The purpose of this study was to define the contribution of mucin N-glycans to the ocular surface glycocalyxl barrier. Methods : Transmembrane mucins were purified from stratified corneal epithelial cell cultures using size exclusion chromatography and isopycnic density centrifugation. N-glycans released from mucin isolates were analyzed by liquid chromatography and electrospray ionization mass spectroscopy. N-glycosylation was inhibited using chemical, enzymatic and siRNA (MGAT1) approaches. Plasma membrane proteins were labeled by biotinylation. Lectin blot, immunoblot, and qPCR were used to determine levels of carbohydrate, protein, and mRNA, ...
To determine the distribution of Blastocystis sp. subtypes from Blastocystis cyst excreters, 1,000 fecal samples from patients suspected of enteroparasitic disease were scored for stool consistency, submitted to xenic in vitro culture (XIVC), formol ethyl acetate concentration (FECT) with subsequent isopycnic centrifugation, and polymerase chain reaction (PCR) with subtype (ST) analysis. Blastocystis was significantly more prevalent in specimens from patients with travel-associated diarrhea (15.6%) than those with persistent diarrhea (8.3%) (P = 0.005). Overall, 115 (11.5%) and 35 (3.5%) specimens were positive by XIVC and FECT, respectively. Blastocystis cysts were detected in 33 (28.7%) of the XIVC-positive specimens. A positive FECT result was associated with ST3 (P = 0.05). The presence of Blastocystis in general or Blastocystis cysts was independent of stool consistency, and no particular ST was significantly associated with cyst identification. In view of these data, the present study indicates
TY - JOUR. T1 - Fractions of HeLa DNA differing in their content of guanine + cytosine. AU - Schildkraut, Carl L.. AU - Maio, Joseph J.. PY - 1969/12/14. Y1 - 1969/12/14. N2 - DNA isolated from preparations of HeLa cell nucleoli has been fractionated into six components which band in CsCl at densities corresponding to their G + C contents according to the relation: ρ{variant} = 0.98 (G + C) + 1.659, where ρ{variant} refers to buoyant density and (G + C) to the average mole fraction of guanine + cytosine. This nucleolar DNA is significantly enriched with respect to two satellite bands: a light satellite (ρ{variant} = 1.686 g/ml.) and a heavy satellite (ρ{variant} = 1.712 g/ml.). In an alkaline CsCl density gradient, the light satellite DNA can be separated into two complementary strands, as demonstrated by base composition analysis.. AB - DNA isolated from preparations of HeLa cell nucleoli has been fractionated into six components which band in CsCl at densities corresponding to their G + C ...
LDL vs. HDL: There are two major kinds of cholesterol: low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Lipoproteins are made out of proteins and…. Continue Reading →. ...
There are two most-heard kinds of lipoproteins, one combination of Cholesterol and protein when travelling through the bloodstream, namely low-density lipoprotein (LDL) and high-density lipoprotein (HDL). LDL is also called bad cholesterol and HDL is called good good cholesterol. Basing … Read more →. ...
Although malignant tumors are known to display extreme heterogeneity, overexpression of SR-B1 is a relatively consistent marker in cancerous tissues. While SR-B1 normally mediates the transfer of cholesterol between high-density lipoproteins (HDL) and healthy cells, it also facilitates the selective uptake of cholesterol by malignant cells. In this way, upregulation of the SR-B1 receptor becomes an enabling factor for self-sufficient proliferation in cancerous tissue.[12][13] SR-B1 mediated delivery has also been used in the transfection of cancer cells with siRNA, or small interfering RNAs. This therapy causes RNA interference, in which short segments of double stranded RNA acts to silence targeted oncogenes post-transcription. SR-B1 mediation reduces siRNA degradation and off-target accumulation while enhancing delivery to targeted tissues. In "metastatic and taxane-resistant models of ovarian cancer, rHDL-mediated siren delivery improved responses.[14] ...
High-density lipoprotein (HDL) amounts inversely correlate with cardiovascular occasions thanks to the protective results on vascular wall structure and control cells, which are susceptible to oxidative modifications and lead to potential pro-atherosclerotic effects then. aspect. Results triggered by ox-HDL could end up being considerably attenuated by pretreatment with brief hairpin RNA-mediated CD36 knockdown or probucol. Data of Rabbit polyclonal to MCAM tests and the inverse correlation of ox-HDL and circulating EPC figures among individuals with coronary artery diseases (CAD) or CAD and type 2 diabetes also supported it. In the mean time, HDL separated from such individuals could significantly increase cultured EPCs caspase 3 activity, further supporting our proposal. This is definitely the most total study to day of how ox-HDL would impair EPCs function, which was involved with service of CD36-p38 MAPK-TSP-1 pathways and proved by not only the inverse relationship between ox-HDL and ...
Register for a screening session at various Penn locations now through December 5 to complete the first step towards being in the know and earning incentives. The full screening schedule is available at the Be in the Know web page.. At the biometric screening, a health educator will measure key indicators of your overall health, including blood pressure, total cholesterol, high density lipoprotein (HDL) cholesterol, and blood sugar (glucose levels).. If you have obtained screening results through your health care provider between July 1 and December 23, 2014, you can submit your completed Health Screenings Documentation Form directly to AreUFit by December 23, 2014 to receive biometric screening credit.. Step 2: Take an online health assessment (January 12 - February 27, 2015) ...
What has previously been known as good cholesterol--high density lipoprotein (HDL)--has now been shown to be not so good in protecting women against atherosclerosis while they are transitioning through menopause, according to a new study from the University of Pittsburgh Graduate School of Public Health that was presented last week at the annual me
I am having trouble isolating mtDNA using CsCl gradients. Is there an easier way to isolate mtDNA? I was wondering if anyone could give me some help! This is becoming a really big problem!!!!! Thank oyu very much, Rodney Earl Pettway Rodney Earl Pettway Department of Plant Pathology and Microbiology Texas A&M University College Station, TX 77843 Pettway at ppserver.tamu.edu ...
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TY - JOUR. T1 - Characterization of apical and basolateral plasma membrane domains derived from cultured rat cholangiocytes. AU - Tietz, Pamela. AU - Levine, Susan. AU - Holman, Ralph. AU - Fretham, Chris. AU - La Russo, Nicholas F. PY - 1997/12/15. Y1 - 1997/12/15. N2 - Cholangiocytes, the epithelial cells that line intrahepatic bile ducts, are composed of plasma membranes with discrete apical (lumenal) and basolateral domains that contain different channels, transporters, and receptors. In recent work, we developed a long-term, primary culture system of normal rat cholangiocytes (NRC). Our aims here were to prepare and characterize apical and basolateral plasma membrane vesicles from NRC. Using serial isopycnic centrifugation on sucrose gradients, we generated separate apical and basolateral plasma membrane vesicles. We characterized these vesicles by transmission electron microscopy, specific marker enzyme assays, and immunoblotting; we also determined the percentage of sealed vesicles and ...
High cholesterol is if the low-density lipoprotein (LDL) levels acceleration aloft accustomed and the high-density lipoprotein (HDL) levels abatement too low. If this bawdiness occurs in the body, it puts one at a aloft accident for top claret pressure, stroke, acuteness ache and diabetes. Added advice visits our website herbalcureindia.com. Diet for Top Cholesterol Shitake […]. ...
However, statins, such Valtrsx simvastatin, are extremely the association option of choice in people with certain LDL zaps and those at high risk of anecdotal heart disease. A: There are many years between Tricor fenofibrate versus Valtrexx Zocor simvastatin for the contraceptive of high blood. Cemetery Health. Two blast-controlled clinical trials were conducted to compare the arteries of Valtrex in adult and autoimmune breakthroughs, 12 years of age and older, with a good of recurrent cold sores. You can also buy Valtrex online at UK Meds. Catalyst with Tricor is used primarly to poor triglyceride gets and active high-density lipoprotein HDL or "good c holesterol" spends. Valacyclovir mg-RAN, blue, autumn, film coated. Even among a cold sore with your serum, then grind someone else, can pass the virus, so wash hands thoroughly when you have an aphrodisiac. Continue to take Valtrex until the full year amount is used. Skip the saw dose if it is almost time for your next prostatic dose. The ...
For Electron Density puzzles, the recipe offers various types of density analysis. The density analysis has several sections. The density report appears as a default option on puzzles with a density component.. The first section of density analysis looks at density by amino acid type. Some amino acids outscore others. For example, tyrosine might average a density subscore near 50, but glycine might have average density under 20. The "density by AA" section lists each amino acid found in the puzzle, the number of segments with that AA, the total density score of those segments, and the mean density for that AA. It also lists the worst density score and the corresponding segment number, and best density score and segment number.. The next three sections are similar, but show the density component for "aromatics" (rings) versus non-aromatics, aliphatics versus non-aliphatics, and hydrophobics versus hydrophilics.. Aromatic AAs typically have a much higher density score than non-aromatics. ...
... / insoluble fractions separated by differential centrifugation. FKIPS DCARD stable
Ive been doing the liquid ionic cesium chloride protocol for 4 months. This one calls for 3 grams a day of the cesium, along with about half that much daily potassium. I also wondered about the rate of response compared to what I read online, but then realized most of what I read referenced a dose of 6 or 9 grams daily, meant to be taken for a .... [Chat Online] ...
High pH Therapy is based on the ready uptake of cesium chloride by cancer cells, and is aimed at depriving the cell of glucose while supporting the body with antioxidants and other nutrients.
INDICATIONS Zocor is used for lowering high cholesterol and triglycerides in certain patients. It also increases high-density lipoprotein (HDL, "good") cholesterol levels. It is used along with an appropriate diet. It is used in certain patients to reduce the risk of heart attack, stroke, and death due to coronary heart disease. It is also used to reduce the need for medical procedures to open blocked blood vessels. It is also used in certain patients to reduce the risk of heart attack, stroke, blood vessel blockage, or chest pain caused by angina. Zocor is an HMG-CoA reductase inhibitor, also known as a "statin." It works by reducing the production of certain fatty substances in the body, including cholesterol.. INSTRUCTIONS Use Zocor as directed by your doctor.. ...
Node Smith, ND A new study has suggested that high density lipoprotein (HDL), the "good cholesterol," may not represent the same cardiovascular risk for post-menopausal women.1 The body needs [...] ...
Consuming sugary drinks more than once a day is associated with lower levels of high-density lipoprotein (HDL) cholesterol (the good cholesterol).
... : Designed for use in sucrose density gradient centrifugation, gradient gel electrophoresis, and li
The present invention relates to methods of enriching for desired cell population from cell sources, such as body fluids, dispersed tissue specimens and cultured cells. In particular, the present inve
Lipid patterns were determined in 167 healthy subjects in the age group 28 to 50 years living in an urban area, a suburban area and two rural areas to determine a possible relationship between their serum lipid patterns and food habits. Total cholesterol, high density lipoprotein (HDL)-cholesterol, …
Cesium chloride, White powder/crystalline/beads, 99.99% (Metals basis), Alfa Aesar™ 50g Cesium chloride, White powder/crystalline/beads, 99.99% (Metals basis),...
... : Molecular structure, electron charge density distribution and docking pictures of 4-(2-Methyl sulfanyl-6-phenyl-pyrimidine-4-yl)-phenol (Molecule No. 8) with Enoyl ACP Reductase (2NTV ...
The possibility of differentiating between chromaffin vesicles with different catecholamine contents was tested by studying the distribution of rabbit adrenal dopamine β-hydroxylase (EC 1.14.21) and catecholamines, and the buoyant densities of the catecholamine storage vesicles after isopycnic centrifugation of crude storage vesicle fractions in sucrose density gradients. Catecholamine storage vesicles were prepared from adrenal glands of untreated rabbits, rabbits which had received chlorisondamine chloride (10/kg intraperitoneally) to block ganglionic transmission, and rabbits which had received both chlorisondamine chloride and reserpine (1 mg kg). Adrenal glands were examined 1 day after treatmenmt with chlorisondamine and 1 and 8 days after combined treatment with chlorisondamine and reserpine. Intact storage vesicles obtained from glands of untreated animals had a specific gravity of 1.27, while the membranes obtained from vesicles lysed in distilled water had a specific gravity of 1.12. ...
Covalently closed circular DNA molecules were isolated from Plasmodium falciparum total DNA by isopycnic centrifugation in CsCl gradients containing either ethidium bromide or 2,6-diamidino-2-phenylindole. The circular molecules had an average contour length of 11.1 +/- 0.5 micron, similar to the analogous molecules previously isolated from the simian malaria parasite P. knowlesi. Both circular molecules shared considerable sequence homology and conserved restriction sites. The nucleotide sequence of one 936 bp fragment of the P. falciparum molecule was determined and identified, by a data base homology search, as part of a mitochondrial small rRNA subunit, thus confirming the mitochondrial origin of the circular DNAs of both malarial species.. ...
Studies on the composition and structure of plant viruses can only be attempted after their purification from infected tissue homogenates. Owing to their intrinsic differences, however, the ease with which different viruses can be purified varies considerably. A few relatively stable viruses, e.g. tobacco mosaic virus or turnip yellow mosaic virus, can be treated with high concentrations of salt and precipitated by acid or alcohol without inactivation. With less stable viruses such methods are usually unsuccessful. The particles of such viruses, however, can be sedimented by ultracentrifugation and procedures developed frequently involve two treatments: (a) differential centrifugation and concentration after initial clarification of buffered homogenates such as with organic solvents (Steere, 1956; Tomlinson, Shepherd & Walker, 1959; Wetter, 1960), (b) further fractionation by rate or equilibrium density gradient centrifugation as developed by Brakke (1960). Because of the small capacity of the
Dear Reader,. A heart-y congratulations is in order for your commitment to regular physical activity. Its also great that youre keen to get to the bottom of your blood test results. All the talk about "good" and "bad" cholesterol, can make figuring out your cholesterol numbers a little confusing. First, the basics - cholesterol is made up of low-density lipoproteins (LDL) and high-density lipoproteins (HDL). Youre correct in your knowledge about the difference between HDL and LDL - HDL is the type of cholesterol that is beneficial for the body because it carts away cholesterol to the liver, which then removes it from the body. Generally speaking, a higher HDL level is recommended and an HDL level between 40 to 50 milligrams per deciliter (mg/dL) is good (while a level higher than 60 mg/dL is even better). So, when it comes to the "good" stuff, youre almost there! On the flipside, a lower level of LDL is advised, but youre right on track because an LDL level of 124 mg/dL falls into the ...
Results: Compared with those who remained economically stable, people who experienced consistent economic insecurity (using both measures) had worsened levels of high-density lipoprotein (HDL)-cholesterol, triglycerides, C reactive protein (CRP), fibrinogen and glycated haemoglobin. Increased economic insecurity was associated with adverse levels of HDL-cholesterol (0.955, 95% CI 0.929 to 0.982), triglycerides (1.077, 95% CI 1.018 to 1.139) and CRP (1.114, 95% CI 1.012 to 1.227), using the measure of financial strain. Results for the other measure were generally consistent, apart from the higher levels of gamma-glutamyl transferase observed among those experiencing persistent insecurity (1.200, 95% CI 1.110 to 1.297 ...
The pH Therapy Basic Package 1 with Cesium Chloride and Potassium is designed to be used in conjunction with an alkalizing diet and lifestyle change.
Another applicable technique is cofractionation in sucrose (or other material) gradients using isopycnic centrifugation.[45] ...
Variations of this include Isopycnic centrifugation, Differential centrifugation, and Sucrose gradient centrifugation. A blood ...
H2 Caesium chloride is widely used in centrifugation in a technique known as isopycnic centrifugation. Centripetal and ... Caesium chloride is widely used medicine structure in isopycnic centrifugation for separating various types of DNA. It is a ...
Another applicable technique is cofractionation in sucrose (or other material) gradients using isopycnic centrifugation.[45] ...
It is a white water-soluble solid that is used to prepare dense aqueous solutions for use in isopycnic (or "density-gradient") ... centrifugation. It is isostructural with potassium salt. Coordination sphere of one of two types of Cs+ site in Cs2SO4. ...
... into them can be separated from biomarkers containing the more naturally abundant lighter isotope by isopycnic centrifugation. ... As the biomarker, DNA with 13C is then separated from DNA with 12C by centrifugation. Sequencing the DNA identifies which ...
... used to separate certain organelles from whole cells for further analysis of specific parts of cells Isopycnic centrifugation, ... Centrifugation Methods. John Wiley & Sons, Mar 4, 2004, pp. 247-267. Frothingham, R (February 1999). "Centrifugation without a ... There are various types of centrifugation: Differential centrifugation, often ... Another potential hazard is the aerosolization of hazardous samples during centrifugation. To prevent contamination of the ...
... centrifugation refers to a method wherein a density gradient is either pre-formed or forms during high speed ... An isopycnic surface is a surface of constant density inside a fluid. In geology, Isopycnic surfaces occur especially in ... These formations are, relative to other lithospheric formations, cooler and less dense but much more isopycnic. Isopycnic ... Isopycnic typically describes surfaces, not processes. Unless there is a flux of mass into or out of a control volume, a ...
Main articles: Differential centrifugation, Isopycnic centrifugation, and ultracentrifugation. Ultracentrifugation makes use of ... Differential CentrifugationEdit. Differential Centrifugation is a type of centrifugation in which one selectively spins down ... "Centrifugation Basics". Sigma-Aldrich. Retrieved 10 May 2016.. *^ Article on "Centrifugation" retrieved on 15 October 2013 from ... Density Gradient CentrifugationEdit. Density gradient centrifugation is considered one of the more efficient methods of ...
Another applicable technique is cofractionation in sucrose (or other material) gradients using isopycnic centrifugation.[49] ...
... and 24 Mycoplasma species by a new method that combines a micro-scale preparation of DNA with isopycnic gradient centrifugation ... Determination of the Guanine-Plus-Cytosine Content of Mollicutes by Isopycnic Gradient Centrifugation * H. Kirchhoff and J. ... and 24 Mycoplasma species by a new method that combines a micro-scale preparation of DNA with isopycnic gradient centrifugation ...
... isopycnic? Find out information about Centrifugation, isopycnic. A line on a chart connecting all points of equal or constant ... Of equal or constant density, with respect to either space or time Explanation of Centrifugation, isopycnic ... Related to Centrifugation, isopycnic: Differential centrifugation, density gradient centrifugation isopycnic. [¦ī·sō¦pik·nik] ( ... isopycnic. (redirected from Centrifugation, isopycnic). Also found in: Dictionary. ...
Isopycnic Centrifugation Principal. by Bill Williams January 20, 2018, 11:04 am. 1.5k Views ... For isopycnic centrifugation, it is needed mostly for maximum density. There is no compound which can possess all the traits ... While using isopycnic centrifugation, the particles can never sediment to the bottom of the tube regardless of the time. ... Isopycnic centrifugation is also known as equilibrium or buoyant separation. It is the process of separating particles or ...
Isopycnic centrifugation* XPB* Gene cassette* Ori (genetics)* RpoB* Eukaryotic chromosome structure* Eukaryotic intergenic DNA* ...
The text then reviews isopycnic centrifugation in ionic media and analytical centrifugation. Topics include separation by ... Isopycnic Zonal Experiments Time to Reach Equilibrium Resolution of Isopycnic Zones Interaction Between Solutes in Isopycnic ... 7 Isopycnic Centrifugation in Non-Ionic Media. General Techniques Density-Gradient Solutes Monosaccharides and Disaccharides ... 6 Isopycnic Centrifugation in Ionic Media Basic Procedures Optimum Design of Buoyant Density-Gradient Separations Equilibrium ...
Centrifugation is the use of the centrifugal forces generated in a spinning rotor to separate biological particles, such as ... isopycnic centrifugation separates particles on the basis of their density. The choice of centrifugation method depends on the ... Figure 2. Differential centrifugation of a homogenate: (a) before centrifugation and (b) after centrifugation. ... centrifugation and isopycnic centrifugation. The first two methods separate particles primarily on the basis of size while ...
Isopycnic gradient centrifugation of EMVs. EMVs were purified from differentiated C2C12 cells. C2C12 cells were seeded onto T- ... and during substantial and lengthy procedures which included isopycnic gradient centrifugation and Exoquick-TC precipitation ( ... After centrifugation and washing in 70% ethanol, the DNA pellet was air-dried at room temperature for 20 minutes. The pellet ... C2C12 cell cultures infected with eGFP-CVB3 were collected at day 3 PI and purified by Isopycnic gradient centrifugation. ...
Centrifugation, Isopycnic. A technique used to separate particles according to their densities in a continuous density gradient ... Centrifugation, Density Gradient. Separation of particles according to density by employing a gradient of varying densities. At ... The sample is usually mixed with a solution of known gradient materials and subjected to centrifugation. Each particle ...
Analytical fractionation by isopycnic density gradient centrifugation of LDM. Each fraction was tested for its content p97, ... Low-density microsomes were separated by isopycnic density gradient centrifugation on linear sucrose gradients (d1.05-1.25). ...
Types of centrifugation. Differential centrifugation. Rate-zonal centrifugation. Isopycnic centrifugation. Differential ... Isopycnic centrifugation. Mostly used to separate nucleic acids.. Based solely on the density of the particles.. Unaffected by ... Rate-zonal centrifugation. Centrifugation medium is characterized by a positive increment in density density gradient.. Sample ... Centrifugation. The separation of subcellular fractions is achieved by centrifugation.. Particles of different density, size, ...
Isopycnic centrifugation.The isopycnic centrifugation of the RNA in cesium trifluoroacetate (CsTFA; GE Healthcare) gradients ... RNA was extracted from root material and rhizosphere soil and subjected to cesium gradient centrifugation followed by 16S rRNA ... Labeled and unlabeled microbial RNA can be separated by density gradient centrifugation in order to identify the microbial ...
Another applicable technique is cofractionation in sucrose (or other material) gradients using isopycnic centrifugation.[45] ...
1999) Measurement of the density of polymeric nanoparticulate drug carriers by isopycnic centrifugation. J Nanoparticle Res 1: ... Apts were separated from the remaining NP supernatant by centrifugation by 12,000 × g for 30 min. After centrifugation, ... and the remaining organic solvent was removed by washing the NPs three times by using an Amicon centrifugation filtration ...
Categories: Centrifugation, Isopycnic Image Types: Photo, Illustrations, Video, Color, Black&White, PublicDomain, ...
The resulting linear plasmid was purified by isopycnic centrifugation at 58,000 rpm, 20°C for 24 hours with a CsCl gradient ... The final product was purified using isopycnic centrifugation. The fraction containing the closed circular form of plasmid was ... 5E). The final site-specific circular plasmid, pGLuc9temG+ICL, was purified by isopycnic ultracentrifugation (Fig. 5f). With ...
Isolation of enriched cardiomyocyte populations by isopycnic centrifugation is illustrated in Examples 4 and 9. Starting with ... After centrifugation, cells on top of the Percoll™ (fraction I) and a layer of cells in the interface of two layers of Percoll ... Four-Phase Centrifugation Separation Method. Cardiomyocytes were generated from hES cells of the H7 line by forming embryoid ... For example, cardiomyocytes are collected by centrifugation at 1000 rpm for 5 min, and then mRNA is prepared from the pellet by ...
Isopycnic centrifugation in cesium trifluoroacetate yielded RNA with the lowest possible amounts of contaminating DNA. This ...
Variations of this include Isopycnic centrifugation, Differential centrifugation, and Sucrose gradient centrifugation. A blood ...
Isopycnic centrifugation and gradient fractionation was done as previously described (Glaubitz et al., 2009; Kleindienst et al ... and rRNA-based stable isotope probing by fractionation and quantitative analysis of isopycnic centrifugation gradients. Environ ... 2014) with 750 ng of total RNA loaded into each gradient and collection of 12 RNA fractions after centrifugation. ...
Viruses were gradient-purified by CsCl isopycnic centrifugation, dialyzed against HEPES-buffered saline (in mm: 10 HEPES, 140 ... Cytoplasmic proteins were obtained by centrifugation at 12,000 rpm for 15 min at 4°C. The proteins (50 μg) were separated on ...
Organelles were separated by isopycnic centrifugation at 116,000 g for 2 h in a NVT65 rotor (Beckman Coulter). Fractions of 1 ... Peroxisomes were isolated from 20kgP fractions of Pex25-pA and Yor084-pA strains by isopycnic centrifugation. The gradients ... Organelles in the 20kgP were separated by isopycnic centrifugation. Proteins were identified in each fraction by Western ... The membranes and associated components (Ti8P) were harvested by centrifugation. Chimeras of Pex25p and the membrane proteins ...
Another applicable technique is cofractionation in sucrose (or other material) gradients using isopycnic centrifugation.[45] ...
Subcellular distribution of [125I]gelonin was established after differential and isopycnic centrifugation. Fractions were ...
2B and C, right panel, and Table 2) or isopycnic centrifugation (Fig. 2D, right panel, and Table 2). The results obtained by ... Labeling and purification of virus by isopycnic and rate-zonal centrifugation methods.Subconfluent monolayers of C6/36 cells in ... Based on three separate determinations of the prM cleavage efficiency after radiolabeling and isopycnic centrifugation, an ... virus-infected cells were separated from nonparticulate components in the culture medium by isopycnic centrifugation. Following ...
H2 Caesium chloride is widely used in centrifugation in a technique known as isopycnic centrifugation. Centripetal and ... Caesium chloride is widely used medicine structure in isopycnic centrifugation for separating various types of DNA. It is a ...
  • Whole homogenate of guinea-pig small intestine mucosa was analysed by centrifugation in a zonal rotor. (athabascau.ca)
  • 1. Rate dependent and isopycnic banding in a zonal rotor were used to analyse the subcellular sites of enzymes in homogenates of guinea-pig small intestinal mucosa. (athabascau.ca)
  • RNA was extracted from root material and rhizosphere soil and subjected to cesium gradient centrifugation followed by 16S rRNA amplicon pyrosequencing to identify microorganisms enriched with 13 C. Thirty operational taxonomic units (OTUs) were labeled and mostly corresponded to Proteobacteria (13 OTUs) and Verrucomicrobia (8 OTUs). (asm.org)
  • A single DNA band formed along a cesium chloride gradient after isopycnic centrifugation of extracts from soils incubated with H 2 16 O. With extracts from soils to which only H 2 18 O was added, two distinct DNA bands formed, while three bands formed when DNA extracted from soil incubated with both H 2 18 O and toluene was analyzed. (asm.org)