A nucleoside that substitutes for thymidine in DNA and thus acts as an antimetabolite. It causes breaks in chromosomes and has been proposed as an antiviral and antineoplastic agent. It has been given orphan drug status for use in the treatment of primary brain tumors.
The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.
Drugs that are chemically similar to naturally occurring metabolites, but differ enough to interfere with normal metabolic pathways. (From AMA Drug Evaluations Annual, 1994, p2033)
5-Bromo-2,4(1H,3H)-pyrimidinedione. Brominated derivative of uracil that acts as an antimetabolite, substituting for thymine in DNA. It is used mainly as an experimental mutagen, but its deoxyriboside (BROMODEOXYURIDINE) is used to treat neoplasms.
All of the processes involved in increasing CELL NUMBER including CELL DIVISION.
Thymidine is a pyrimidine nucleoside, consisting of a thymine base linked to a deoxyribose sugar by a β-N1-glycosidic bond, which plays a crucial role in DNA replication and repair processes as one of the four nucleosides in DNA.
The number of CELLS of a specific kind, usually measured per unit volume or area of sample.
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).
The process by which a DNA molecule is duplicated.
The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.
Formation of NEURONS which involves the differentiation and division of STEM CELLS in which one or both of the daughter cells become neurons.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
Phase of the CELL CYCLE following G1 and preceding G2 when the entire DNA content of the nucleus is replicated. It is achieved by bidirectional replication at multiple sites along each chromosome.
Nuclear antigen with a role in DNA synthesis, DNA repair, and cell cycle progression. PCNA is required for the coordinated synthesis of both leading and lagging strands at the replication fork during DNA replication. PCNA expression correlates with the proliferation activity of several malignant and non-malignant cell types.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
An analog of DEOXYURIDINE that inhibits viral DNA synthesis. The drug is used as an antiviral agent.
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.
An expression of the number of mitoses found in a stated number of cells.
Relatively undifferentiated cells that retain the ability to divide and proliferate throughout postnatal life to provide progenitor cells that can differentiate into specialized cells.
GRAY MATTER situated above the GYRUS HIPPOCAMPI. It is composed of three layers. The molecular layer is continuous with the HIPPOCAMPUS in the hippocampal fissure. The granular layer consists of closely arranged spherical or oval neurons, called GRANULE CELLS, whose AXONS pass through the polymorphic layer ending on the DENDRITES of PYRAMIDAL CELLS in the hippocampus.
Elements of limited time intervals, contributing to particular results or situations.
Tritium is an isotope of hydrogen (specifically, hydrogen-3) that contains one proton and two neutrons in its nucleus, making it radioactive with a half-life of about 12.3 years, and is used in various applications including nuclear research, illumination, and dating techniques due to its low energy beta decay.
Established cell cultures that have the potential to propagate indefinitely.
An exchange of segments between the sister chromatids of a chromosome, either between the sister chromatids of a meiotic tetrad or between the sister chromatids of a duplicated somatic chromosome. Its frequency is increased by ultraviolet and ionizing radiation and other mutagenic agents and is particularly high in BLOOM SYNDROME.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species.
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.
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.
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
F344 rats are an inbred strain of albino laboratory rats (Rattus norvegicus) that have been widely used in biomedical research due to their consistent and reliable genetic background, which facilitates the study of disease mechanisms and therapeutic interventions.
A type VI intermediate filament protein expressed mostly in nerve cells where it is associated with the survival, renewal and mitogen-stimulated proliferation of neural progenitor cells.
The physiological renewal, repair, or replacement of tissue.
That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.
2'-Deoxyuridine. An antimetabolite that is converted to deoxyuridine triphosphate during DNA synthesis. Laboratory suppression of deoxyuridine is used to diagnose megaloblastic anemias due to vitamin B12 and folate deficiencies.
Refers to animals in the period of time just after birth.
Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.
The reformation of all, or part of, the native conformation of a nucleic acid molecule after the molecule has undergone denaturation.
One of the early purine analogs showing antineoplastic activity. It functions as an antimetabolite and is easily incorporated into ribonucleic acids.
An enzyme that catalyzes the conversion of ATP and thymidine to ADP and thymidine 5'-phosphate. Deoxyuridine can also act as an acceptor and dGTP as a donor. (From Enzyme Nomenclature, 1992) EC 2.7.1.21.
A folic acid derivative used as a rodenticide that has been shown to be teratogenic.
Phosphate esters of THYMIDINE in N-glycosidic linkage with ribose or deoxyribose, as occurs in nucleic acids. (From Dorland, 28th ed, p1154)
An intermediate filament protein found only in glial cells or cells of glial origin. MW 51,000.
The effects of ionizing and nonionizing radiation upon living organisms, organs and tissues, and their constituents, and upon physiologic processes. It includes the effect of irradiation on food, drugs, and chemicals.
A CELL CYCLE and tumor growth marker which can be readily detected using IMMUNOCYTOCHEMISTRY methods. Ki-67 is a nuclear antigen present only in the nuclei of cycling cells.
An antineoplastic antimetabolite that is metabolized to fluorouracil when administered by rapid injection; when administered by slow, continuous, intra-arterial infusion, it is converted to floxuridine monophosphate. It has been used to treat hepatic metastases of gastrointestinal adenocarcinomas and for palliation in malignant neoplasms of the liver and gastrointestinal tract.
The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.
A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.
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)
Substances that increase the risk of NEOPLASMS in humans or animals. Both genotoxic chemicals, which affect DNA directly, and nongenotoxic chemicals, which induce neoplasms by other mechanism, are included.
DNA present in neoplastic tissue.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
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.
Uracil nucleotides which contain deoxyribose as the sugar moiety.
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)
An increase in the number of cells in a tissue or organ without tumor formation. It differs from HYPERTROPHY, which is an increase in bulk without an increase in the number of cells.
An in situ method for detecting areas of DNA which are nicked during APOPTOSIS. Terminal deoxynucleotidyl transferase is used to add labeled dUTP, in a template-independent manner, to the 3 prime OH ends of either single- or double-stranded DNA. The terminal deoxynucleotidyl transferase nick end labeling, or TUNEL, assay labels apoptosis on a single-cell level, making it more sensitive than agarose gel electrophoresis for analysis of DNA FRAGMENTATION.
Repair or renewal of hepatic tissue.
Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
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.
Filaments 7-11 nm in diameter found in the cytoplasm of all cells. Many specific proteins belong to this group, e.g., desmin, vimentin, prekeratin, decamin, skeletin, neurofilin, neurofilament protein, and glial fibrillary acid protein.
Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.
Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.
A circumscribed benign epithelial tumor projecting from the surrounding surface; more precisely, a benign epithelial neoplasm consisting of villous or arborescent outgrowths of fibrovascular stroma covered by neoplastic cells. (Stedman, 25th ed)
The relationship between the dose of an administered drug and the response of the organism to the drug.
The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the BLOOD-BRAIN BARRIER and BLOOD-RETINAL BARRIER, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear.
Self-renewing cells that generate the main phenotypes of the nervous system in both the embryo and adult. Neural stem cells are precursors to both NEURONS and NEUROGLIA.
The interval between two successive CELL DIVISIONS during which the CHROMOSOMES are not individually distinguishable. It is composed of the G phases (G1 PHASE; G0 PHASE; G2 PHASE) and S PHASE (when DNA replication occurs).
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.
A potent mutagen and carcinogen. This compound and its metabolite 4-HYDROXYAMINOQUINOLINE-1-OXIDE bind to nucleic acids. It inactivates bacteria but not bacteriophage.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
The period of the CELL CYCLE preceding DNA REPLICATION in S PHASE. Subphases of G1 include "competence" (to respond to growth factors), G1a (entry into G1), G1b (progression), and G1c (assembly). Progression through the G1 subphases is effected by limiting growth factors, nutrients, or inhibitors.
Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.
A purine or pyrimidine base bonded to a DEOXYRIBOSE containing a bond to a phosphate group.
The rate dynamics in chemical or physical systems.
Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.
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.
An enzyme that catalyzes the conversion of L-TYROSINE and 2-oxoglutarate to 4-hydroxyphenylpyruvate and L-GLUTAMATE. It is a pyridoxal-phosphate protein. L-PHENYLALANINE is hydroxylated to L-tyrosine. The mitochondrial enzyme may be identical with ASPARTATE AMINOTRANSFERASES (EC 2.6.1.1.). Deficiency of this enzyme may cause type II Tyrosinemia (see TYROSINEMIAS). EC 2.6.1.5.
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.
Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
An intermediate filament protein found in most differentiating cells, in cells grown in tissue culture, and in certain fully differentiated cells. Its insolubility suggests that it serves a structural function in the cytoplasm. MW 52,000.
A single-chain polypeptide growth factor that plays a significant role in the process of WOUND HEALING and is a potent inducer of PHYSIOLOGIC ANGIOGENESIS. Several different forms of the human protein exist ranging from 18-24 kDa in size due to the use of alternative start sites within the fgf-2 gene. It has a 55 percent amino acid residue identity to FIBROBLAST GROWTH FACTOR 1 and has potent heparin-binding activity. The growth factor is an extremely potent inducer of DNA synthesis in a variety of cell types from mesoderm and neuroectoderm lineages. It was originally named basic fibroblast growth factor based upon its chemical properties and to distinguish it from acidic fibroblast growth factor (FIBROBLAST GROWTH FACTOR 1).
A hydro-lyase that catalyzes the dehydration of 2-phosphoglycerate to form PHOSPHOENOLPYRUVATE. Several different isoforms of this enzyme exist, each with its own tissue specificity.
Cavity in each of the CEREBRAL HEMISPHERES derived from the cavity of the embryonic NEURAL TUBE. They are separated from each other by the SEPTUM PELLUCIDUM, and each communicates with the THIRD VENTRICLE by the foramen of Monro, through which also the choroid plexuses (CHOROID PLEXUS) of the lateral ventricles become continuous with that of the third ventricle.
A thin membrane that lines the CEREBRAL VENTRICLES and the central canal of the SPINAL CORD.
Uridine is a nucleoside, specifically a derivative of pyrimidine, that is composed of a uracil molecule joined to a ribose sugar molecule through a β-N1 glycosidic bond, and has significant roles in RNA synthesis, energy transfer, and cell signaling.
The measurement of an organ in volume, mass, or heaviness.
The segment of LARGE INTESTINE between the CECUM and the RECTUM. It includes the ASCENDING COLON; the TRANSVERSE COLON; the DESCENDING COLON; and the SIGMOID COLON.
A group of genetically identical cells all descended from a single common ancestral cell by mitosis in eukaryotes or by binary fission in prokaryotes. Clone cells also include populations of recombinant DNA molecules all carrying the same inserted sequence. (From King & Stansfield, Dictionary of Genetics, 4th ed)
Experimentally induced tumors of the LIVER.
Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.
A pyrimidine nucleoside analog that is used mainly in the treatment of leukemia, especially acute non-lymphoblastic leukemia. Cytarabine is an antimetabolite antineoplastic agent that inhibits the synthesis of DNA. Its actions are specific for the S phase of the cell cycle. It also has antiviral and immunosuppressant properties. (From Martindale, The Extra Pharmacopoeia, 30th ed, p472)
Deoxyribonucleic acid that makes up the genetic material of viruses.
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. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.

The incorporation of 5-iodo-2'-deoxyuridine into the DNA of HeLa cells and the induction of alkaline phosphatase activity. (1/3497)

Inhibition of DNA synthesis during the period of exposure of HeLa cells to 5-iodo-2'-deoxyuridine (IUdR) inhibited the induction of alkaline phosphatase activity. This finding, taken together with previous findings that IUdR did not induce alkaline phosphatase activity in the presence of 2-fold molar excess thymidinemonstrated that IUdR incorporation into DNA is correlated with the increase in alkaline phosphatase activity. With the exception of an interim period described in the text, induction of alkaline phosphatase activity was linearly related to medium concentrations of IUdR of up to at least 3 muM. However, the extent of IUdR substitution in DNA did not appear to be related to the degree of enzyme induction. Alkaline phosphatase activity continued to increase at medium concentrations of IUdR from 1 to 3 muM, while little further substitution of DNA occurred.  (+info)

High-throughput screening of small molecules in miniaturized mammalian cell-based assays involving post-translational modifications. (2/3497)

BACKGROUND: Fully adapting a forward genetic approach to mammalian systems requires efficient methods to alter systematically gene products without prior knowledge of gene sequences, while allowing for the subsequent characterization of these alterations. Ideally, these methods would also allow function to be altered in a temporally controlled manner. RESULTS: We report the development of a miniaturized cell-based assay format that enables a genetic-like approach to understanding cellular pathways in mammalian systems using small molecules, rather than mutations, as the source of gene-product alterations. This whole-cell immunodetection assay can sensitively detect changes in specific cellular macromolecules in high-density arrays of mammalian cells. Furthermore, it is compatible with screening large numbers of small molecules in nanoliter to microliter culture volumes. We refer to this assay format as a 'cytoblot', and demonstrate the use of cytoblotting to monitor biosynthetic processes such as DNA synthesis, and post-translational processes such as acetylation and phosphorylation. Finally, we demonstrate the applicability of these assays to natural-product screening through the identification of marine sponge extracts exhibiting genotype-specific inhibition of 5-bromodeoxyuridine incorporation and suppression of the anti-proliferative effect of rapamycin. CONCLUSIONS: We show that cytoblots can be used for high-throughput screening of small molecules in cell-based assays. Together with small-molecule libraries, the cytoblot assay can be used to perform chemical genetic screens analogous to those used in classical genetics and thus should be applicable to understanding a wide variety of cellular processes, especially those involving post-transitional modifications.  (+info)

Herpetic keratitis. Proctor Lecture. (3/3497)

Although much needs to be learned about the serious clinical problem of herpes infection of the cornea, we have come a long way. We now have effective topical antiviral drugs. We have animal models which, with a high degree of reliability, clearly predict the effect to be expected clinically in man, as well as the toxicity. We have systemically active drugs and the potential of getting highly active, potent, completely selective drugs, with the possibility that perhaps the source of viral reinfection can be eradicated. The biology of recurrent herpes and stromal disease is gradually being understood, and this understanding may result in new and better therapy of this devastating clinical disease.  (+info)

Immunochemical detection and isolation of DNA from metabolically active bacteria. (4/3497)

Most techniques used to assay the growth of microbes in natural communities provide no information on the relationship between microbial productivity and community structure. To identify actively growing bacteria, we adapted a technique from immunocytochemistry to detect and selectively isolate DNA from bacteria incorporating bromodeoxyuridine (BrdU), a thymidine analog. In addition, we developed an immunocytochemical protocol to visualize BrdU-labeled microbial cells. Cultured bacteria and natural populations of aquatic bacterioplankton were pulse-labeled with exogenously supplied BrdU. Incorporation of BrdU into microbial DNA was demonstrated in DNA dot blots probed with anti-BrdU monoclonal antibodies and either peroxidase- or Texas red-conjugated secondary antibodies. BrdU-containing DNA was physically separated from unlabeled DNA by using antibody-coated paramagnetic beads, and the identities of bacteria contributing to both purified, BrdU-containing fractions and unfractionated, starting-material DNAs were determined by length heterogeneity PCR (LH-PCR) analysis. BrdU-containing DNA purified from a mixture of DNAs from labeled and unlabeled cultures showed >90-fold enrichment for the labeled bacterial taxon. The LH-PCR profile for BrdU-containing DNA from a labeled, natural microbial community differed from the profile for the community as a whole, demonstrating that BrdU was incorporated by a taxonomic subset of the community. Immunocytochemical detection of cells with BrdU-labeled DNA was accomplished by in situ probing with anti-BrdU monoclonal antibodies and Texas red-labeled secondary antibodies. Using this suite of techniques, microbial cells incorporating BrdU into their newly synthesized DNA can be quantified and the identities of these actively growing cells can be compared to the composition of the microbial community as a whole. Since not all strains tested could incorporate BrdU, these methods may be most useful when used to gain an understanding of the activities of specific species in the context of their microbial community.  (+info)

Proteolipid protein gene product can be secreted and exhibit biological activity during early development. (5/3497)

A gene encoding myelin proteolipid protein (PLP) and its smaller isoform DM20 is expressed at least 1 week before myelination. Mutations within the gene cause abnormalities in the development of premyelinating oligodendrocytes, resulting in hypomyelinating disorders. These findings suggest a premyelinating function of the PLP gene products. We previously demonstrated that PLP gene expression is directly associated with secretion of a factor that increases the number of oligodendrocytes. Here we show that this activity is mediated by a secreted fragment containing the C-terminal portion of PLP. This factor increased the bromodeoxyuridine incorporation rate in both oligodendrocyte and astrocyte lineage cells; a synthetic peptide (PLP 215-232) exhibited a similar activity. Dose-response curves of PLP and PLP peptide showed maximum activities at a concentration in the picomolar range, which decreased at higher concentrations. These observations demonstrate that a secreted PLP gene product exerts biological activity at a premyelinating stage before the major induction of the gene.  (+info)

Embryonic and postnatal injections of bromodeoxyuridine produce age-dependent morphological and behavioral abnormalities. (6/3497)

The mitotic marker 5-bromodeoxyuridine (BrdU) was injected twice daily (60 mg/kg) into pregnant hooded rats on one of embryonic days (E) 11, 12, 13, 15, 17, or 21, or into rat pups on postnatal day (P) 10. The principal findings were the following: (1) BrdU exposure on E11 produces profound effects on body morphology, and animals must be fed a special diet because of chronic tooth abnormalities; (2) BrdU exposure at E17 or earlier produces a change in coat spotting pattern, the precise pattern varying with age; (3) BrdU exposure on E15 or earlier produces a reduction in both brain and body weight; (4) BrdU exposure on E17 or earlier reduces cortical thickness; (5) BrdU exposure on E11-E13 and at P10 reduces cerebellar size relative to cerebral size; (6) spatial learning is significantly affected after injections of BrdU at E11-E17, but the largest effect is on E17; (7) the deficit in spatial learning may be related in part to a reduction in visual acuity; and (8) skilled forelimb ability is most disrupted after BrdU exposure at E15 but is also impaired after injections on E13 or earlier. BrdU thus has teratological effects on body, brain, and behavior that vary with the developmental age of the fetus or infant.  (+info)

Capsaicin-sensitive C-fiber-mediated protective responses in ozone inhalation in rats. (7/3497)

To assess the role of lung sensory C fibers during and after inhalation of 1 part/million ozone for 8 h, we compared breathing pattern responses and epithelial injury-inflammation-repair in rats depleted of C fibers by systemic administration of capsaicin as neonates and in vehicle-treated control animals. Capsaicin-treated rats did not develop ozone-induced rapid, shallow breathing. Capsaicin-treated rats showed more severe necrosis in the nasal cavity and greater inflammation throughout the respiratory tract than did control rats exposed to ozone. Incorporation of 5-bromo-2'-deoxyuridine (a marker of DNA synthesis associated with proliferation) into terminal bronchiolar epithelial cells was not significantly affected by capsaicin treatment in rats exposed to ozone. However, when normalized to the degree of epithelial necrosis present in each rat studied, there was less 5-bromo-2'-deoxyuridine labeling in the terminal bronchioles of capsaicin-treated rats. These observations suggest that the ozone-induced release of neuropeptides does not measurably contribute to airway inflammation but may play a role in modulating basal and reparative airway epithelial cell proliferation.  (+info)

Retinal neurogenesis: the formation of the initial central patch of postmitotic cells. (8/3497)

We have investigated the relationship between the birthdate and the onset of differentiation of neurons in the embryonic zebrafish neural retina. Birthdates were established by a single injection of bromodeoxyuridine into embryos of closely spaced ages. Differentiation was revealed in the same embryos with a neuron-specific antibody, zn12. The first bromodeoxyuridine-negative (postmitotic) cells occupied the ganglion cell layer of ventronasal retina, where they formed a small cluster of 10 cells or less that included the first zn12-positive cells (neurons). New cells were recruited to both populations (bromodeoxyuridine-negative and zn12-positive) along the same front, similar to the unfolding of a fan, to produce a circular central patch of hundreds of cells in the ganglion cell layer about 9 h later. Thus the formation of this central patch, previously considered as the start of retinal neurogenesis, was actually a secondary event, with a developmental history of its own. The first neurons outside the ganglion cell layer also appeared in ventronasal retina, indicating that the ventronasal region was the site of initiation of all retinal neurogenesis. Within a column (a small cluster of neuroepithelial cells), postmitotic cells appeared first in the ganglion cell layer, then the inner nuclear layer, and then the outer nuclear layer, so cell birthday and cell fate were correlated within a column. The terminal mitoses occurred in three bursts separated by two 10-h intervals during which proliferation continued without terminal mitoses.  (+info)

Bromodeoxyuridine (BrdU) is a synthetic thymidine analog that can be incorporated into DNA during cell replication. It is often used in research and medical settings as a marker for cell proliferation or as a tool to investigate DNA synthesis and repair. When cells are labeled with BrdU and then examined using immunofluorescence or other detection techniques, the presence of BrdU can indicate which cells have recently divided or are actively synthesizing DNA.

In medical contexts, BrdU has been used in cancer research to study tumor growth and response to treatment. It has also been explored as a potential therapeutic agent for certain conditions, such as neurodegenerative diseases, where promoting cell proliferation and replacement of damaged cells may be beneficial. However, its use as a therapeutic agent is still experimental and requires further investigation.

Cell division is the process by which a single eukaryotic cell (a cell with a true nucleus) divides into two identical daughter cells. This complex process involves several stages, including replication of DNA, separation of chromosomes, and division of the cytoplasm. There are two main types of cell division: mitosis and meiosis.

Mitosis is the type of cell division that results in two genetically identical daughter cells. It is a fundamental process for growth, development, and tissue repair in multicellular organisms. The stages of mitosis include prophase, prometaphase, metaphase, anaphase, and telophase, followed by cytokinesis, which divides the cytoplasm.

Meiosis, on the other hand, is a type of cell division that occurs in the gonads (ovaries and testes) during the production of gametes (sex cells). Meiosis results in four genetically unique daughter cells, each with half the number of chromosomes as the parent cell. This process is essential for sexual reproduction and genetic diversity. The stages of meiosis include meiosis I and meiosis II, which are further divided into prophase, prometaphase, metaphase, anaphase, and telophase.

In summary, cell division is the process by which a single cell divides into two daughter cells, either through mitosis or meiosis. This process is critical for growth, development, tissue repair, and sexual reproduction in multicellular organisms.

Antimetabolites are a class of drugs that interfere with the normal metabolic processes of cells, particularly those involved in DNA replication and cell division. They are commonly used as chemotherapeutic agents to treat various types of cancer because many cancer cells divide more rapidly than normal cells. Antimetabolites work by mimicking natural substances needed for cell growth and division, such as nucleotides or amino acids, and getting incorporated into the growing cells' DNA or protein structures, which ultimately leads to the termination of cell division and death of the cancer cells. Examples of antimetabolites include methotrexate, 5-fluorouracil, and capecitabine.

Bromouracil is a chemical compound that is used in the synthesis of DNA. It is a brominated derivative of uracil, which is one of the nucleobases found in RNA. Bromouracil can be incorporated into DNA during replication in place of thymine, another nucleobase. This can lead to mutations in the DNA because bromouracil behaves differently from thymine in certain chemical reactions.

Bromouracil is not typically found in living organisms and is not considered to be a normal part of the genetic material. It may be used in research settings to study the mechanisms of DNA replication and mutation. In clinical medicine, bromouracil has been used in the treatment of psoriasis, a skin condition characterized by red, scaly patches. However, its use in this context is not common.

It is important to note that bromouracil can have toxic effects and should be handled with care. It can cause irritation to the skin and eyes, and prolonged exposure may lead to more serious health problems. If you have any questions about bromouracil or its use, it is best to speak with a healthcare professional or a qualified scientist.

Cell proliferation is the process by which cells increase in number, typically through the process of cell division. In the context of biology and medicine, it refers to the reproduction of cells that makes up living tissue, allowing growth, maintenance, and repair. It involves several stages including the transition from a phase of quiescence (G0 phase) to an active phase (G1 phase), DNA replication in the S phase, and mitosis or M phase, where the cell divides into two daughter cells.

Abnormal or uncontrolled cell proliferation is a characteristic feature of many diseases, including cancer, where deregulated cell cycle control leads to excessive and unregulated growth of cells, forming tumors that can invade surrounding tissues and metastasize to distant sites in the body.

Thymidine is a pyrimidine nucleoside that consists of a thymine base linked to a deoxyribose sugar by a β-N1-glycosidic bond. It plays a crucial role in DNA replication and repair processes as one of the four nucleosides in DNA, along with adenosine, guanosine, and cytidine. Thymidine is also used in research and clinical settings for various purposes, such as studying DNA synthesis or as a component of antiviral and anticancer therapies.

"Cell count" is a medical term that refers to the process of determining the number of cells present in a given volume or sample of fluid or tissue. This can be done through various laboratory methods, such as counting individual cells under a microscope using a specialized grid called a hemocytometer, or using automated cell counters that use light scattering and electrical impedance techniques to count and classify different types of cells.

Cell counts are used in a variety of medical contexts, including hematology (the study of blood and blood-forming tissues), microbiology (the study of microscopic organisms), and pathology (the study of diseases and their causes). For example, a complete blood count (CBC) is a routine laboratory test that includes a white blood cell (WBC) count, red blood cell (RBC) count, hemoglobin level, hematocrit value, and platelet count. Abnormal cell counts can indicate the presence of various medical conditions, such as infections, anemia, or leukemia.

Deoxyribonucleic acid (DNA) is the genetic material present in the cells of organisms where it is responsible for the storage and transmission of hereditary information. DNA is a long molecule that consists of two strands coiled together to form a double helix. Each strand is made up of a series of four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - that are linked together by phosphate and sugar groups. The sequence of these bases along the length of the molecule encodes genetic information, with A always pairing with T and C always pairing with G. This base-pairing allows for the replication and transcription of DNA, which are essential processes in the functioning and reproduction of all living organisms.

DNA replication is the biological process by which DNA makes an identical copy of itself during cell division. It is a fundamental mechanism that allows genetic information to be passed down from one generation of cells to the next. During DNA replication, each strand of the double helix serves as a template for the synthesis of a new complementary strand. This results in the creation of two identical DNA molecules. The enzymes responsible for DNA replication include helicase, which unwinds the double helix, and polymerase, which adds nucleotides to the growing strands.

The cell cycle is a series of events that take place in a cell leading to its division and duplication. It consists of four main phases: G1 phase, S phase, G2 phase, and M phase.

During the G1 phase, the cell grows in size and synthesizes mRNA and proteins in preparation for DNA replication. In the S phase, the cell's DNA is copied, resulting in two complete sets of chromosomes. During the G2 phase, the cell continues to grow and produces more proteins and organelles necessary for cell division.

The M phase is the final stage of the cell cycle and consists of mitosis (nuclear division) and cytokinesis (cytoplasmic division). Mitosis results in two genetically identical daughter nuclei, while cytokinesis divides the cytoplasm and creates two separate daughter cells.

The cell cycle is regulated by various checkpoints that ensure the proper completion of each phase before progressing to the next. These checkpoints help prevent errors in DNA replication and division, which can lead to mutations and cancer.

Neurogenesis is the process by which new neurons (nerve cells) are generated in the brain. It occurs throughout life in certain areas of the brain, such as the hippocampus and subventricular zone, although the rate of neurogenesis decreases with age. Neurogenesis involves the proliferation, differentiation, and integration of new neurons into existing neural circuits. This process plays a crucial role in learning, memory, and recovery from brain injury or disease.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

In the context of cell biology, "S phase" refers to the part of the cell cycle during which DNA replication occurs. The "S" stands for synthesis, reflecting the active DNA synthesis that takes place during this phase. It is preceded by G1 phase (gap 1) and followed by G2 phase (gap 2), with mitosis (M phase) being the final stage of the cell cycle.

During S phase, the cell's DNA content effectively doubles as each chromosome is replicated to ensure that the two resulting daughter cells will have the same genetic material as the parent cell. This process is carefully regulated and coordinated with other events in the cell cycle to maintain genomic stability.

Proliferating Cell Nuclear Antigen (PCNA) is a protein that plays an essential role in the process of DNA replication and repair in eukaryotic cells. It functions as a cofactor for DNA polymerase delta, enhancing its activity during DNA synthesis. PCNA forms a sliding clamp around DNA, allowing it to move along the template and coordinate the actions of various enzymes involved in DNA metabolism.

PCNA is often used as a marker for cell proliferation because its levels increase in cells that are actively dividing or have been stimulated to enter the cell cycle. Immunostaining techniques can be used to detect PCNA and determine the proliferative status of tissues or cultures. In this context, 'proliferating' refers to the rapid multiplication of cells through cell division.

Cell differentiation is the process by which a less specialized cell, or stem cell, becomes a more specialized cell type with specific functions and structures. This process involves changes in gene expression, which are regulated by various intracellular signaling pathways and transcription factors. Differentiation results in the development of distinct cell types that make up tissues and organs in multicellular organisms. It is a crucial aspect of embryonic development, tissue repair, and maintenance of homeostasis in the body.

Idoxuridine is an antiviral medication used primarily for the treatment of herpes simplex virus (HSV) infections of the eye, such as keratitis or dendritic ulcers. It works by interfering with the DNA replication of the virus, thereby inhibiting its ability to multiply and spread.

Idoxuridine is available as an ophthalmic solution (eye drops) and is typically applied directly to the affected eye every 1-2 hours while awake, for up to 2 weeks. Common side effects include local irritation, stinging, or burning upon application. Prolonged use of idoxuridine may lead to bacterial resistance or corneal toxicity, so it is important to follow your healthcare provider's instructions carefully when using this medication.

It is essential to note that idoxuridine is not commonly used today due to the development of more effective and less toxic antiviral agents for HSV infections.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

The Mitotic Index (MI) is a measure of cell proliferation that reflects the percentage of cells in a population or sample that are undergoing mitosis, which is the process of cell division. It is often expressed as the number of mitotic figures (dividing cells) per 100 or 1,000 cells counted in a microscopic field. The Mitotic Index is used in various fields, including pathology and research, to assess the growth fraction of cells in tissues or cultures, and to monitor the effects of treatments that affect cell division, such as chemotherapy or radiation therapy.

According to the National Institutes of Health (NIH), stem cells are "initial cells" or "precursor cells" that have the ability to differentiate into many different cell types in the body. They can also divide without limit to replenish other cells for as long as the person or animal is still alive.

There are two main types of stem cells: embryonic stem cells, which come from human embryos, and adult stem cells, which are found in various tissues throughout the body. Embryonic stem cells have the ability to differentiate into all cell types in the body, while adult stem cells have more limited differentiation potential.

Stem cells play an essential role in the development and repair of various tissues and organs in the body. They are currently being studied for their potential use in the treatment of a wide range of diseases and conditions, including cancer, diabetes, heart disease, and neurological disorders. However, more research is needed to fully understand the properties and capabilities of these cells before they can be used safely and effectively in clinical settings.

The dentate gyrus is a region of the brain that is located in the hippocampal formation, which is a part of the limbic system and plays a crucial role in learning, memory, and spatial navigation. It is characterized by the presence of densely packed granule cells, which are a type of neuron. The dentate gyrus is involved in the formation of new memories and the integration of information from different brain regions. It is also one of the few areas of the adult brain where new neurons can be generated throughout life, a process known as neurogenesis. Damage to the dentate gyrus has been linked to memory impairments, cognitive decline, and neurological disorders such as Alzheimer's disease and epilepsy.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Tritium is not a medical term, but it is a term used in the field of nuclear physics and chemistry. Tritium (symbol: T or 3H) is a radioactive isotope of hydrogen with two neutrons and one proton in its nucleus. It is also known as heavy hydrogen or superheavy hydrogen.

Tritium has a half-life of about 12.3 years, which means that it decays by emitting a low-energy beta particle (an electron) to become helium-3. Due to its radioactive nature and relatively short half-life, tritium is used in various applications, including nuclear weapons, fusion reactors, luminous paints, and medical research.

In the context of medicine, tritium may be used as a radioactive tracer in some scientific studies or medical research, but it is not a term commonly used to describe a medical condition or treatment.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Sister chromatid exchange (SCE) is a type of genetic recombination that takes place between two identical sister chromatids during the DNA repair process in meiosis or mitosis. It results in an exchange of genetic material between the two chromatids, creating a new combination of genes on each chromatid. This event is a normal part of cell division and helps to increase genetic variability within a population. However, an increased rate of SCEs can also be indicative of exposure to certain genotoxic agents or conditions that cause DNA damage.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

Mitosis is a type of cell division in which the genetic material of a single cell, called the mother cell, is equally distributed into two identical daughter cells. It's a fundamental process that occurs in multicellular organisms for growth, maintenance, and repair, as well as in unicellular organisms for reproduction.

The process of mitosis can be broken down into several stages: prophase, prometaphase, metaphase, anaphase, and telophase. During prophase, the chromosomes condense and become visible, and the nuclear envelope breaks down. In prometaphase, the nuclear membrane is completely disassembled, and the mitotic spindle fibers attach to the chromosomes at their centromeres.

During metaphase, the chromosomes align at the metaphase plate, an imaginary line equidistant from the two spindle poles. In anaphase, sister chromatids are pulled apart by the spindle fibers and move toward opposite poles of the cell. Finally, in telophase, new nuclear envelopes form around each set of chromosomes, and the chromosomes decondense and become less visible.

Mitosis is followed by cytokinesis, a process that divides the cytoplasm of the mother cell into two separate daughter cells. The result of mitosis and cytokinesis is two genetically identical cells, each with the same number and kind of chromosomes as the original parent cell.

Neurons, also known as nerve cells or neurocytes, are specialized cells that constitute the basic unit of the nervous system. They are responsible for receiving, processing, and transmitting information and signals within the body. Neurons have three main parts: the dendrites, the cell body (soma), and the axon. The dendrites receive signals from other neurons or sensory receptors, while the axon transmits these signals to other neurons, muscles, or glands. The junction between two neurons is called a synapse, where neurotransmitters are released to transmit the signal across the gap (synaptic cleft) to the next neuron. Neurons vary in size, shape, and structure depending on their function and location within the nervous system.

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

Cell survival refers to the ability of a cell to continue living and functioning normally, despite being exposed to potentially harmful conditions or treatments. This can include exposure to toxins, radiation, chemotherapeutic drugs, or other stressors that can damage cells or interfere with their normal processes.

In scientific research, measures of cell survival are often used to evaluate the effectiveness of various therapies or treatments. For example, researchers may expose cells to a particular drug or treatment and then measure the percentage of cells that survive to assess its potential therapeutic value. Similarly, in toxicology studies, measures of cell survival can help to determine the safety of various chemicals or substances.

It's important to note that cell survival is not the same as cell proliferation, which refers to the ability of cells to divide and multiply. While some treatments may promote cell survival, they may also inhibit cell proliferation, making them useful for treating diseases such as cancer. Conversely, other treatments may be designed to specifically target and kill cancer cells, even if it means sacrificing some healthy cells in the process.

'Staining and labeling' are techniques commonly used in pathology, histology, cytology, and molecular biology to highlight or identify specific components or structures within tissues, cells, or molecules. These methods enable researchers and medical professionals to visualize and analyze the distribution, localization, and interaction of biological entities, contributing to a better understanding of diseases, cellular processes, and potential therapeutic targets.

Medical definitions for 'staining' and 'labeling' are as follows:

1. Staining: A process that involves applying dyes or stains to tissues, cells, or molecules to enhance their contrast and reveal specific structures or components. Stains can be categorized into basic stains (which highlight acidic structures) and acidic stains (which highlight basic structures). Common staining techniques include Hematoxylin and Eosin (H&E), which differentiates cell nuclei from the surrounding cytoplasm and extracellular matrix; special stains, such as PAS (Periodic Acid-Schiff) for carbohydrates or Masson's trichrome for collagen fibers; and immunostains, which use antibodies to target specific proteins.
2. Labeling: A process that involves attaching a detectable marker or tag to a molecule of interest, allowing its identification, quantification, or tracking within a biological system. Labels can be direct, where the marker is directly conjugated to the targeting molecule, or indirect, where an intermediate linker molecule is used to attach the label to the target. Common labeling techniques include fluorescent labels (such as FITC, TRITC, or Alexa Fluor), enzymatic labels (such as horseradish peroxidase or alkaline phosphatase), and radioactive labels (such as ³²P or ¹⁴C). Labeling is often used in conjunction with staining techniques to enhance the specificity and sensitivity of detection.

Together, staining and labeling provide valuable tools for medical research, diagnostics, and therapeutic development, offering insights into cellular and molecular processes that underlie health and disease.

Flow cytometry is a medical and research technique used to measure physical and chemical characteristics of cells or particles, one cell at a time, as they flow in a fluid stream through a beam of light. The properties measured include:

* Cell size (light scatter)
* Cell internal complexity (granularity, also light scatter)
* Presence or absence of specific proteins or other molecules on the cell surface or inside the cell (using fluorescent antibodies or other fluorescent probes)

The technique is widely used in cell counting, cell sorting, protein engineering, biomarker discovery and monitoring disease progression, particularly in hematology, immunology, and cancer research.

Apoptosis is a programmed and controlled cell death process that occurs in multicellular organisms. It is a natural process that helps maintain tissue homeostasis by eliminating damaged, infected, or unwanted cells. During apoptosis, the cell undergoes a series of morphological changes, including cell shrinkage, chromatin condensation, and fragmentation into membrane-bound vesicles called apoptotic bodies. These bodies are then recognized and engulfed by neighboring cells or phagocytic cells, preventing an inflammatory response. Apoptosis is regulated by a complex network of intracellular signaling pathways that involve proteins such as caspases, Bcl-2 family members, and inhibitors of apoptosis (IAPs).

F344 is a strain code used to designate an outbred stock of rats that has been inbreeded for over 100 generations. The F344 rats, also known as Fischer 344 rats, were originally developed at the National Institutes of Health (NIH) and are now widely used in biomedical research due to their consistent and reliable genetic background.

Inbred strains, like the F344, are created by mating genetically identical individuals (siblings or parents and offspring) for many generations until a state of complete homozygosity is reached, meaning that all members of the strain have identical genomes. This genetic uniformity makes inbred strains ideal for use in studies where consistent and reproducible results are important.

F344 rats are known for their longevity, with a median lifespan of around 27-31 months, making them useful for aging research. They also have a relatively low incidence of spontaneous tumors compared to other rat strains. However, they may be more susceptible to certain types of cancer and other diseases due to their inbred status.

It's important to note that while F344 rats are often used as a standard laboratory rat strain, there can still be some genetic variation between individual animals within the same strain, particularly if they come from different suppliers or breeding colonies. Therefore, it's always important to consider the source and history of any animal model when designing experiments and interpreting results.

Nestin is a type of class VI intermediate filament protein that is primarily expressed in various types of undifferentiated or progenitor cells in the nervous system, including neural stem cells and progenitor cells. It is often used as a marker for these cells due to its expression during stages of active cell division and migration. Nestin is also expressed in some other tissues undergoing regeneration or injury.

Regeneration in a medical context refers to the process of renewal, restoration, and growth that replaces damaged or missing cells, tissues, organs, or even whole limbs in some organisms. This complex biological process involves various cellular and molecular mechanisms, such as cell proliferation, differentiation, and migration, which work together to restore the structural and functional integrity of the affected area.

In human medicine, regeneration has attracted significant interest due to its potential therapeutic applications in treating various conditions, including degenerative diseases, trauma, and congenital disorders. Researchers are actively studying the underlying mechanisms of regeneration in various model organisms to develop novel strategies for promoting tissue repair and regeneration in humans.

Examples of regeneration in human medicine include liver regeneration after partial hepatectomy, where the remaining liver lobes can grow back to their original size within weeks, and skin wound healing, where keratinocytes migrate and proliferate to close the wound and restore the epidermal layer. However, the regenerative capacity of humans is limited compared to some other organisms, such as planarians and axolotls, which can regenerate entire body parts or even their central nervous system.

According to the medical definition, ultraviolet (UV) rays are invisible radiations that fall in the range of the electromagnetic spectrum between 100-400 nanometers. UV rays are further divided into three categories: UVA (320-400 nm), UVB (280-320 nm), and UVC (100-280 nm).

UV rays have various sources, including the sun and artificial sources like tanning beds. Prolonged exposure to UV rays can cause damage to the skin, leading to premature aging, eye damage, and an increased risk of skin cancer. UVA rays penetrate deeper into the skin and are associated with skin aging, while UVB rays primarily affect the outer layer of the skin and are linked to sunburns and skin cancer. UVC rays are the most harmful but fortunately, they are absorbed by the Earth's atmosphere and do not reach the surface.

Healthcare professionals recommend limiting exposure to UV rays, wearing protective clothing, using broad-spectrum sunscreen with an SPF of at least 30, and avoiding tanning beds to reduce the risk of UV-related health problems.

Deoxyuridine is a chemical compound that is a component of DNA. It is a nucleoside, which means it consists of a sugar (deoxyribose) linked to a nitrogenous base (uracil). In the case of deoxyuridine, the uracil is not methylated, which differentiates it from thymidine.

Deoxyuridine can be converted into deoxyuridine monophosphate (dUMP) by the enzyme thymidine kinase. The dUMP can then be converted into deoxythymidine triphosphate (dTTP), which is a building block of DNA, through a series of reactions involving other enzymes.

Deoxyuridine has been used in research and medicine as a marker for DNA synthesis and repair. It can also be used to inhibit the growth of certain types of cells, such as cancer cells, by disrupting their DNA synthesis.

"Newborn animals" refers to the very young offspring of animals that have recently been born. In medical terminology, newborns are often referred to as "neonates," and they are classified as such from birth until about 28 days of age. During this time period, newborn animals are particularly vulnerable and require close monitoring and care to ensure their survival and healthy development.

The specific needs of newborn animals can vary widely depending on the species, but generally, they require warmth, nutrition, hydration, and protection from harm. In many cases, newborns are unable to regulate their own body temperature or feed themselves, so they rely heavily on their mothers for care and support.

In medical settings, newborn animals may be examined and treated by veterinarians to ensure that they are healthy and receiving the care they need. This can include providing medical interventions such as feeding tubes, antibiotics, or other treatments as needed to address any health issues that arise. Overall, the care and support of newborn animals is an important aspect of animal medicine and conservation efforts.

Epithelial cells are types of cells that cover the outer surfaces of the body, line the inner surfaces of organs and glands, and form the lining of blood vessels and body cavities. They provide a protective barrier against the external environment, regulate the movement of materials between the internal and external environments, and are involved in the sense of touch, temperature, and pain. Epithelial cells can be squamous (flat and thin), cuboidal (square-shaped and of equal height), or columnar (tall and narrow) in shape and are classified based on their location and function.

Nucleic acid renaturation, also known as nucleic acid reassociation or hybridization, is the process of rejoining two complementary single-stranded nucleic acids (DNA or RNA) to form a double-stranded structure. This process occurs naturally in cells during transcription and DNA replication, but it can also be performed in vitro as a laboratory technique.

Renaturation typically involves denaturing the double-stranded nucleic acids into single strands by heat or chemical methods, followed by controlled cooling or modification of conditions to allow the complementary strands to find each other and reanneal. The rate and specificity of renaturation can be used to study the relatedness and concentration of nucleic acid sequences in a sample.

In molecular biology research, nucleic acid renaturation is often used in techniques such as Southern blotting, Northern blotting, and polymerase chain reaction (PCR) to detect and analyze specific DNA or RNA sequences.

Azaguanine is a type of antimetabolite drug that is used in medical research and treatment. It is a purine analogue, which means it has a similar chemical structure to the natural purine bases adenine and guanine, which are building blocks of DNA and RNA. Azaguanine can be incorporated into the genetic material of cells, interfering with their normal function and replication. It is used in research to study the effects of such interference on cell growth and development.

In clinical medicine, azaguanine has been used as an anticancer drug, although it is not widely used today due to its toxicity and the availability of more effective treatments. It may also have some activity against certain types of parasitic infections, such as leishmaniasis and malaria.

It's important to note that azaguanine is not a commonly used medication and its use should be under the supervision of a medical professional with experience in its administration and management of potential side effects.

Thymidine kinase (TK) is an enzyme that plays a crucial role in the synthesis of thymidine triphosphate (dTMP), a nucleotide required for DNA replication and repair. It catalyzes the phosphorylation of thymidine to thymidine monophosphate (dTMP) by transferring a phosphate group from adenosine triphosphate (ATP).

There are two major isoforms of thymidine kinase in humans: TK1 and TK2. TK1 is primarily found in the cytoplasm of proliferating cells, such as those involved in the cell cycle, while TK2 is located mainly in the mitochondria and is responsible for maintaining the dNTP pool required for mtDNA replication and repair.

Thymidine kinase activity has been used as a marker for cell proliferation, particularly in cancer cells, which often exhibit elevated levels of TK1 due to their high turnover rates. Additionally, measuring TK1 levels can help monitor the effectiveness of certain anticancer therapies that target DNA replication.

Aminopterin is a type of anti-folate drug that is primarily used in cancer treatment and research. It works by inhibiting the enzyme dihydrofolate reductase, which is necessary for the synthesis of nucleotides, the building blocks of DNA and RNA. By blocking this enzyme, aminopterin prevents the growth and multiplication of cancer cells.

In addition to its use in cancer treatment, aminopterin has also been used in experimental studies to investigate the role of folate metabolism in various biological processes, including embryonic development and immune function. However, due to its potent anti-proliferative effects, the use of aminopterin is limited to specialized medical and research settings, and it is not commonly used as a therapeutic agent in clinical practice.

Thymine nucleotides are biochemical components that play a crucial role in the structure and function of DNA (deoxyribonucleic acid), which is the genetic material present in living organisms. A thymine nucleotide consists of three parts: a sugar molecule called deoxyribose, a phosphate group, and a nitrogenous base called thymine.

Thymine is one of the four nucleobases in DNA, along with adenine, guanine, and cytosine. It specifically pairs with adenine through hydrogen bonding, forming a base pair that is essential for maintaining the structure and stability of the double helix. Thymine nucleotides are linked together by phosphodiester bonds between the sugar molecules of adjacent nucleotides, creating a long, linear polymer known as a DNA strand.

In summary, thymine nucleotides are building blocks of DNA that consist of deoxyribose, a phosphate group, and the nitrogenous base thymine, which pairs with adenine in the double helix structure.

Glial Fibrillary Acidic Protein (GFAP) is a type of intermediate filament protein that is primarily found in astrocytes, which are a type of star-shaped glial cells in the central nervous system (CNS). These proteins play an essential role in maintaining the structural integrity and stability of astrocytes. They also participate in various cellular processes such as responding to injury, providing support to neurons, and regulating the extracellular environment.

GFAP is often used as a marker for astrocytic activation or reactivity, which can occur in response to CNS injuries, neuroinflammation, or neurodegenerative diseases. Elevated GFAP levels in cerebrospinal fluid (CSF) or blood can indicate astrocyte damage or dysfunction and are associated with several neurological conditions, including traumatic brain injury, stroke, multiple sclerosis, Alzheimer's disease, and Alexander's disease.

Radiation effects refer to the damages that occur in living tissues when exposed to ionizing radiation. These effects can be categorized into two types: deterministic and stochastic. Deterministic effects have a threshold dose below which the effect does not occur, and above which the severity of the effect increases with the dose. Examples include radiation-induced erythema, epilation, and organ damage. Stochastic effects, on the other hand, do not have a threshold dose, and the probability of the effect occurring increases with the dose. Examples include genetic mutations and cancer induction. The severity of the effect is not related to the dose in this case.

The Ki-67 antigen is a cellular protein that is expressed in all active phases of the cell cycle (G1, S, G2, and M), but not in the resting phase (G0). It is often used as a marker for cell proliferation and can be found in high concentrations in rapidly dividing cells. Immunohistochemical staining for Ki-67 can help to determine the growth fraction of a group of cells, which can be useful in the diagnosis and prognosis of various malignancies, including cancer. The level of Ki-67 expression is often associated with the aggressiveness of the tumor and its response to treatment.

Floxuridine is a chemotherapeutic antimetabolite medication that is primarily used in the treatment of colon cancer. It is a fluorinated pyrimidine nucleoside analogue, which means it is similar in structure to the building blocks of DNA and RNA, and can be incorporated into these molecules during cell division, disrupting their normal function and preventing cell replication.

Floxuridine works by inhibiting the enzyme thymidylate synthase, which is necessary for the synthesis of thymidine, a nucleoside that is essential for DNA replication. By blocking this enzyme, floxuridine can prevent the growth and proliferation of cancer cells.

Floxuridine is often used in combination with other chemotherapy drugs as part of a treatment regimen for colon cancer. It may be administered intravenously or via continuous infusion, depending on the specific treatment plan. As with all chemotherapy drugs, floxuridine can have significant side effects, including nausea, vomiting, diarrhea, and myelosuppression (suppression of bone marrow function), which can lead to anemia, neutropenia, and thrombocytopenia.

Cell movement, also known as cell motility, refers to the ability of cells to move independently and change their location within tissue or inside the body. This process is essential for various biological functions, including embryonic development, wound healing, immune responses, and cancer metastasis.

There are several types of cell movement, including:

1. **Crawling or mesenchymal migration:** Cells move by extending and retracting protrusions called pseudopodia or filopodia, which contain actin filaments. This type of movement is common in fibroblasts, immune cells, and cancer cells during tissue invasion and metastasis.
2. **Amoeboid migration:** Cells move by changing their shape and squeezing through tight spaces without forming protrusions. This type of movement is often observed in white blood cells (leukocytes) as they migrate through the body to fight infections.
3. **Pseudopodial extension:** Cells extend pseudopodia, which are temporary cytoplasmic projections containing actin filaments. These protrusions help the cell explore its environment and move forward.
4. **Bacterial flagellar motion:** Bacteria use a whip-like structure called a flagellum to propel themselves through their environment. The rotation of the flagellum is driven by a molecular motor in the bacterial cell membrane.
5. **Ciliary and ependymal movement:** Ciliated cells, such as those lining the respiratory tract and fallopian tubes, have hair-like structures called cilia that beat in coordinated waves to move fluids or mucus across the cell surface.

Cell movement is regulated by a complex interplay of signaling pathways, cytoskeletal rearrangements, and adhesion molecules, which enable cells to respond to environmental cues and navigate through tissues.

The hippocampus is a complex, curved formation in the brain that resembles a seahorse (hence its name, from the Greek word "hippos" meaning horse and "kampos" meaning sea monster). It's part of the limbic system and plays crucial roles in the formation of memories, particularly long-term ones.

This region is involved in spatial navigation and cognitive maps, allowing us to recognize locations and remember how to get to them. Additionally, it's one of the first areas affected by Alzheimer's disease, which often results in memory loss as an early symptom.

Anatomically, it consists of two main parts: the Ammon's horn (or cornu ammonis) and the dentate gyrus. These structures are made up of distinct types of neurons that contribute to different aspects of learning and memory.

The cell nucleus is a membrane-bound organelle found in the eukaryotic cells (cells with a true nucleus). It contains most of the cell's genetic material, organized as DNA molecules in complex with proteins, RNA molecules, and histones to form chromosomes.

The primary function of the cell nucleus is to regulate and control the activities of the cell, including growth, metabolism, protein synthesis, and reproduction. It also plays a crucial role in the process of mitosis (cell division) by separating and protecting the genetic material during this process. The nuclear membrane, or nuclear envelope, surrounding the nucleus is composed of two lipid bilayers with numerous pores that allow for the selective transport of molecules between the nucleoplasm (nucleus interior) and the cytoplasm (cell exterior).

The cell nucleus is a vital structure in eukaryotic cells, and its dysfunction can lead to various diseases, including cancer and genetic disorders.

Carcinogens are agents (substances or mixtures of substances) that can cause cancer. They may be naturally occurring or man-made. Carcinogens can increase the risk of cancer by altering cellular DNA, disrupting cellular function, or promoting cell growth. Examples of carcinogens include certain chemicals found in tobacco smoke, asbestos, UV radiation from the sun, and some viruses.

It's important to note that not all exposures to carcinogens will result in cancer, and the risk typically depends on factors such as the level and duration of exposure, individual genetic susceptibility, and lifestyle choices. The International Agency for Research on Cancer (IARC) classifies carcinogens into different groups based on the strength of evidence linking them to cancer:

Group 1: Carcinogenic to humans
Group 2A: Probably carcinogenic to humans
Group 2B: Possibly carcinogenic to humans
Group 3: Not classifiable as to its carcinogenicity to humans
Group 4: Probably not carcinogenic to humans

This information is based on medical research and may be subject to change as new studies become available. Always consult a healthcare professional for medical advice.

The term "DNA, neoplasm" is not a standard medical term or concept. DNA refers to deoxyribonucleic acid, which is the genetic material present in the cells of living organisms. A neoplasm, on the other hand, is a tumor or growth of abnormal tissue that can be benign (non-cancerous) or malignant (cancerous).

In some contexts, "DNA, neoplasm" may refer to genetic alterations found in cancer cells. These genetic changes can include mutations, amplifications, deletions, or rearrangements of DNA sequences that contribute to the development and progression of cancer. Identifying these genetic abnormalities can help doctors diagnose and treat certain types of cancer more effectively.

However, it's important to note that "DNA, neoplasm" is not a term that would typically be used in medical reports or research papers without further clarification. If you have any specific questions about DNA changes in cancer cells or neoplasms, I would recommend consulting with a healthcare professional or conducting further research on the topic.

Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.

The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.

Examples of animal disease models include:

1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.

Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.

The Fluorescent Antibody Technique (FAT) is a type of immunofluorescence assay used in laboratory medicine and pathology for the detection and localization of specific antigens or antibodies in tissues, cells, or microorganisms. In this technique, a fluorescein-labeled antibody is used to selectively bind to the target antigen or antibody, forming an immune complex. When excited by light of a specific wavelength, the fluorescein label emits light at a longer wavelength, typically visualized as green fluorescence under a fluorescence microscope.

The FAT is widely used in diagnostic microbiology for the identification and characterization of various bacteria, viruses, fungi, and parasites. It has also been applied in the diagnosis of autoimmune diseases and certain cancers by detecting specific antibodies or antigens in patient samples. The main advantage of FAT is its high sensitivity and specificity, allowing for accurate detection and differentiation of various pathogens and disease markers. However, it requires specialized equipment and trained personnel to perform and interpret the results.

Deoxyuracil nucleotides are chemical compounds that are the building blocks of DNA. Specifically, they are the form of nucleotides that contain the sugar deoxyribose and the nucleobase deoxyuracil. In DNA, deoxyuracil nucleotides pair with deoxyadenosine nucleotides through base pairing.

Deoxyuracil is a nucleobase that is similar to thymine, but it lacks a methyl group. Thymine is the usual nucleobase that pairs with adenine in DNA, while uracil is typically found in RNA paired with adenine. However, in certain circumstances, such as during DNA repair or damage, deoxyuracil can be incorporated into DNA instead of thymine.

Deoxyuracil nucleotides are important for understanding DNA replication, repair, and mutation. Abnormalities in the incorporation or removal of deoxyuracil nucleotides can lead to genetic disorders, cancer, and other diseases.

Autoradiography is a medical imaging technique used to visualize and localize the distribution of radioactively labeled compounds within tissues or organisms. In this process, the subject is first exposed to a radioactive tracer that binds to specific molecules or structures of interest. The tissue is then placed in close contact with a radiation-sensitive film or detector, such as X-ray film or an imaging plate.

As the radioactive atoms decay, they emit particles (such as beta particles) that interact with the film or detector, causing chemical changes and leaving behind a visible image of the distribution of the labeled compound. The resulting autoradiogram provides information about the location, quantity, and sometimes even the identity of the molecules or structures that have taken up the radioactive tracer.

Autoradiography has been widely used in various fields of biology and medical research, including pharmacology, neuroscience, genetics, and cell biology, to study processes such as protein-DNA interactions, gene expression, drug metabolism, and neuronal connectivity. However, due to the use of radioactive materials and potential hazards associated with them, this technique has been gradually replaced by non-radioactive alternatives like fluorescence in situ hybridization (FISH) or immunofluorescence techniques.

Hyperplasia is a medical term that refers to an abnormal increase in the number of cells in an organ or tissue, leading to an enlargement of the affected area. It's a response to various stimuli such as hormones, chronic irritation, or inflammation. Hyperplasia can be physiological, like the growth of breast tissue during pregnancy, or pathological, like in the case of benign or malignant tumors. The process is generally reversible if the stimulus is removed. It's important to note that hyperplasia itself is not cancerous, but some forms of hyperplasia can increase the risk of developing cancer over time.

In situ nick-end labeling (ISEL, also known as TUNEL) is a technique used in pathology and molecular biology to detect DNA fragmentation, which is a characteristic of apoptotic cells (cells undergoing programmed cell death). The method involves labeling the 3'-hydroxyl termini of double or single stranded DNA breaks in situ (within tissue sections or individual cells) using modified nucleotides that are coupled to a detectable marker, such as a fluorophore or an enzyme. This technique allows for the direct visualization and quantification of apoptotic cells within complex tissues or cell populations.

Liver regeneration is the ability of the liver to restore its original mass and function after injury or surgical resection. This complex process involves the proliferation and differentiation of mature hepatocytes, as well as the activation and transdifferentiation of various types of stem and progenitor cells located in the liver. The mechanisms that regulate liver regeneration include a variety of growth factors, hormones, and cytokines, which act in a coordinated manner to ensure the restoration of normal liver architecture and function. Liver regeneration is essential for the survival of individuals who have undergone partial hepatectomy or who have suffered liver damage due to various causes, such as viral hepatitis, alcohol abuse, or drug-induced liver injury.

Centrifugation, Density Gradient is a medical laboratory technique used to separate and purify different components of a mixture based on their size, density, and shape. This method involves the use of a centrifuge and a density gradient medium, such as sucrose or cesium chloride, to create a stable density gradient within a column or tube.

The sample is carefully layered onto the top of the gradient and then subjected to high-speed centrifugation. During centrifugation, the particles in the sample move through the gradient based on their size, density, and shape, with heavier particles migrating faster and further than lighter ones. This results in the separation of different components of the mixture into distinct bands or zones within the gradient.

This technique is commonly used to purify and concentrate various types of biological materials, such as viruses, organelles, ribosomes, and subcellular fractions, from complex mixtures. It allows for the isolation of pure and intact particles, which can then be collected and analyzed for further study or use in downstream applications.

In summary, Centrifugation, Density Gradient is a medical laboratory technique used to separate and purify different components of a mixture based on their size, density, and shape using a centrifuge and a density gradient medium.

"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.

Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.

Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.

Culture techniques are methods used in microbiology to grow and multiply microorganisms, such as bacteria, fungi, or viruses, in a controlled laboratory environment. These techniques allow for the isolation, identification, and study of specific microorganisms, which is essential for diagnostic purposes, research, and development of medical treatments.

The most common culture technique involves inoculating a sterile growth medium with a sample suspected to contain microorganisms. The growth medium can be solid or liquid and contains nutrients that support the growth of the microorganisms. Common solid growth media include agar plates, while liquid growth media are used for broth cultures.

Once inoculated, the growth medium is incubated at a temperature that favors the growth of the microorganisms being studied. During incubation, the microorganisms multiply and form visible colonies on the solid growth medium or turbid growth in the liquid growth medium. The size, shape, color, and other characteristics of the colonies can provide important clues about the identity of the microorganism.

Other culture techniques include selective and differential media, which are designed to inhibit the growth of certain types of microorganisms while promoting the growth of others, allowing for the isolation and identification of specific pathogens. Enrichment cultures involve adding specific nutrients or factors to a sample to promote the growth of a particular type of microorganism.

Overall, culture techniques are essential tools in microbiology and play a critical role in medical diagnostics, research, and public health.

Intermediate filament proteins (IFPs) are a type of cytoskeletal protein that form the intermediate filaments (IFs), which are one of the three major components of the cytoskeleton in eukaryotic cells, along with microtubules and microfilaments. These proteins have a unique structure, characterized by an alpha-helical rod domain flanked by non-helical head and tail domains.

Intermediate filament proteins are classified into six major types based on their amino acid sequence: Type I (acidic) and Type II (basic) keratins, Type III (desmin, vimentin, glial fibrillary acidic protein, and peripherin), Type IV (neurofilaments), Type V (lamins), and Type VI (nestin). Each type of IFP has a distinct pattern of expression in different tissues and cell types.

Intermediate filament proteins play important roles in maintaining the structural integrity and mechanical strength of cells, providing resilience to mechanical stress, and regulating various cellular processes such as cell division, migration, and signal transduction. Mutations in IFP genes have been associated with several human diseases, including cancer, neurodegenerative disorders, and genetic skin fragility disorders.

Fibroblasts are specialized cells that play a critical role in the body's immune response and wound healing process. They are responsible for producing and maintaining the extracellular matrix (ECM), which is the non-cellular component present within all tissues and organs, providing structural support and biochemical signals for surrounding cells.

Fibroblasts produce various ECM proteins such as collagens, elastin, fibronectin, and laminins, forming a complex network of fibers that give tissues their strength and flexibility. They also help in the regulation of tissue homeostasis by controlling the turnover of ECM components through the process of remodeling.

In response to injury or infection, fibroblasts become activated and start to proliferate rapidly, migrating towards the site of damage. Here, they participate in the inflammatory response, releasing cytokines and chemokines that attract immune cells to the area. Additionally, they deposit new ECM components to help repair the damaged tissue and restore its functionality.

Dysregulation of fibroblast activity has been implicated in several pathological conditions, including fibrosis (excessive scarring), cancer (where they can contribute to tumor growth and progression), and autoimmune diseases (such as rheumatoid arthritis).

The intestinal mucosa is the innermost layer of the intestines, which comes into direct contact with digested food and microbes. It is a specialized epithelial tissue that plays crucial roles in nutrient absorption, barrier function, and immune defense. The intestinal mucosa is composed of several cell types, including absorptive enterocytes, mucus-secreting goblet cells, hormone-producing enteroendocrine cells, and immune cells such as lymphocytes and macrophages.

The surface of the intestinal mucosa is covered by a single layer of epithelial cells, which are joined together by tight junctions to form a protective barrier against harmful substances and microorganisms. This barrier also allows for the selective absorption of nutrients into the bloodstream. The intestinal mucosa also contains numerous lymphoid follicles, known as Peyer's patches, which are involved in immune surveillance and defense against pathogens.

In addition to its role in absorption and immunity, the intestinal mucosa is also capable of producing hormones that regulate digestion and metabolism. Dysfunction of the intestinal mucosa can lead to various gastrointestinal disorders, such as inflammatory bowel disease, celiac disease, and food allergies.

A papilloma is a benign (noncancerous) tumor that grows on a stalk, often appearing as a small cauliflower-like growth. It can develop in various parts of the body, but when it occurs in the mucous membranes lining the respiratory, digestive, or genitourinary tracts, they are called squamous papillomas. The most common type is the skin papilloma, which includes warts. They are usually caused by human papillomavirus (HPV) infection and can be removed through various medical procedures if they become problematic or unsightly.

A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.

The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.

The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.

In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.

Neuroglia, also known as glial cells or simply glia, are non-neuronal cells that provide support and protection for neurons in the nervous system. They maintain homeostasis, form myelin sheaths around nerve fibers, and provide structural support. They also play a role in the immune response of the central nervous system. Some types of neuroglia include astrocytes, oligodendrocytes, microglia, and ependymal cells.

Neural stem cells (NSCs) are a type of undifferentiated cells found in the central nervous system, including the brain and spinal cord. They have the ability to self-renew and generate the main types of cells found in the nervous system, such as neurons, astrocytes, and oligodendrocytes. NSCs are capable of dividing symmetrically to increase their own population or asymmetrically to produce one stem cell and one differentiated cell. They play a crucial role in the development and maintenance of the nervous system, and have the potential to be used in regenerative medicine and therapies for neurological disorders and injuries.

Interphase is a phase in the cell cycle during which the cell primarily performs its functions of growth and DNA replication. It is the longest phase of the cell cycle, consisting of G1 phase (during which the cell grows and prepares for DNA replication), S phase (during which DNA replication occurs), and G2 phase (during which the cell grows further and prepares for mitosis). During interphase, the chromosomes are in their relaxed, extended form and are not visible under the microscope. Interphase is followed by mitosis, during which the chromosomes condense and separate to form two genetically identical daughter cells.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

4-Nitroquinoline-1-oxide is a chemical compound that is often used in laboratory research as a carcinogenic agent. Its molecular formula is C6H4N2O3, and it is known to cause DNA damage and mutations, which can lead to the development of cancer. It is primarily used in scientific research to study the mechanisms of carcinogenesis and to test the effectiveness of potential cancer treatments.

It is important to note that 4-Nitroquinoline-1-oxide is not a medication or a treatment for any medical condition, and it should only be handled by trained professionals in a controlled laboratory setting.

Cricetinae is a subfamily of rodents that includes hamsters, gerbils, and relatives. These small mammals are characterized by having short limbs, compact bodies, and cheek pouches for storing food. They are native to various parts of the world, particularly in Europe, Asia, and Africa. Some species are popular pets due to their small size, easy care, and friendly nature. In a medical context, understanding the biology and behavior of Cricetinae species can be important for individuals who keep them as pets or for researchers studying their physiology.

The G1 phase, or Gap 1 phase, is the first phase of the cell cycle, during which the cell grows in size and synthesizes mRNA and proteins in preparation for subsequent steps leading to mitosis. During this phase, the cell also checks its growth and makes sure that it is large enough to proceed through the cell cycle. If the cell is not large enough, it will arrest in the G1 phase until it has grown sufficiently. The G1 phase is followed by the S phase, during which DNA replication occurs.

Experimental neoplasms refer to abnormal growths or tumors that are induced and studied in a controlled laboratory setting, typically in animals or cell cultures. These studies are conducted to understand the fundamental mechanisms of cancer development, progression, and potential treatment strategies. By manipulating various factors such as genetic mutations, environmental exposures, and pharmacological interventions, researchers can gain valuable insights into the complex processes underlying neoplasm formation and identify novel targets for cancer therapy. It is important to note that experimental neoplasms may not always accurately represent human cancers, and further research is needed to translate these findings into clinically relevant applications.

Deoxyribonucleotides are the building blocks of DNA (deoxyribonucleic acid). They consist of a deoxyribose sugar, a phosphate group, and one of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), or thymine (T). A deoxyribonucleotide is formed when a nucleotide loses a hydroxyl group from its sugar molecule. In DNA, deoxyribonucleotides link together to form a long, double-helix structure through phosphodiester bonds between the sugar of one deoxyribonucleotide and the phosphate group of another. The sequence of these nucleotides carries genetic information that is essential for the development and function of all known living organisms and many viruses.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Neoplastic cell transformation is a process in which a normal cell undergoes genetic alterations that cause it to become cancerous or malignant. This process involves changes in the cell's DNA that result in uncontrolled cell growth and division, loss of contact inhibition, and the ability to invade surrounding tissues and metastasize (spread) to other parts of the body.

Neoplastic transformation can occur as a result of various factors, including genetic mutations, exposure to carcinogens, viral infections, chronic inflammation, and aging. These changes can lead to the activation of oncogenes or the inactivation of tumor suppressor genes, which regulate cell growth and division.

The transformation of normal cells into cancerous cells is a complex and multi-step process that involves multiple genetic and epigenetic alterations. It is characterized by several hallmarks, including sustained proliferative signaling, evasion of growth suppressors, resistance to cell death, enabling replicative immortality, induction of angiogenesis, activation of invasion and metastasis, reprogramming of energy metabolism, and evading immune destruction.

Neoplastic cell transformation is a fundamental concept in cancer biology and is critical for understanding the molecular mechanisms underlying cancer development and progression. It also has important implications for cancer diagnosis, prognosis, and treatment, as identifying the specific genetic alterations that underlie neoplastic transformation can help guide targeted therapies and personalized medicine approaches.

Nucleic acid denaturation is the process of separating the two strands of a double-stranded DNA molecule, or unwinding the helical structure of an RNA molecule, by disrupting the hydrogen bonds that hold the strands together. This process is typically caused by exposure to high temperatures, changes in pH, or the presence of chemicals called denaturants.

Denaturation can also cause changes in the shape and function of nucleic acids. For example, it can disrupt the secondary and tertiary structures of RNA molecules, which can affect their ability to bind to other molecules and carry out their functions within the cell.

In molecular biology, nucleic acid denaturation is often used as a tool for studying the structure and function of nucleic acids. For example, it can be used to separate the two strands of a DNA molecule for sequencing or amplification, or to study the interactions between nucleic acids and other molecules.

It's important to note that denaturation is a reversible process, and under the right conditions, the double-stranded structure of DNA can be restored through a process called renaturation or annealing.

Tyrosine transaminase, also known as tyrosine aminotransferase or TAT, is an enzyme that plays a crucial role in the metabolism of the amino acid tyrosine. This enzyme catalyzes the transfer of an amino group from tyrosine to a ketoacid, such as alpha-ketoglutarate, resulting in the formation of a new amino acid, glutamate, and a ketone derivative of tyrosine.

Tyrosine transaminase is primarily found in the liver and its activity can be used as a biomarker for liver function. Increased levels of this enzyme in the blood may indicate liver damage or disease, such as hepatitis or cirrhosis. Therefore, measuring tyrosine transaminase activity is often part of routine liver function tests.

A chick embryo refers to the developing organism that arises from a fertilized chicken egg. It is often used as a model system in biological research, particularly during the stages of development when many of its organs and systems are forming and can be easily observed and manipulated. The study of chick embryos has contributed significantly to our understanding of various aspects of developmental biology, including gastrulation, neurulation, organogenesis, and pattern formation. Researchers may use various techniques to observe and manipulate the chick embryo, such as surgical alterations, cell labeling, and exposure to drugs or other agents.

Transgenic mice are genetically modified rodents that have incorporated foreign DNA (exogenous DNA) into their own genome. This is typically done through the use of recombinant DNA technology, where a specific gene or genetic sequence of interest is isolated and then introduced into the mouse embryo. The resulting transgenic mice can then express the protein encoded by the foreign gene, allowing researchers to study its function in a living organism.

The process of creating transgenic mice usually involves microinjecting the exogenous DNA into the pronucleus of a fertilized egg, which is then implanted into a surrogate mother. The offspring that result from this procedure are screened for the presence of the foreign DNA, and those that carry the desired genetic modification are used to establish a transgenic mouse line.

Transgenic mice have been widely used in biomedical research to model human diseases, study gene function, and test new therapies. They provide a valuable tool for understanding complex biological processes and developing new treatments for a variety of medical conditions.

A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

Vimentin is a type III intermediate filament protein that is expressed in various cell types, including mesenchymal cells, endothelial cells, and hematopoietic cells. It plays a crucial role in maintaining cell structure and integrity by forming part of the cytoskeleton. Vimentin is also involved in various cellular processes such as cell division, motility, and intracellular transport.

In addition to its structural functions, vimentin has been identified as a marker for epithelial-mesenchymal transition (EMT), a process that occurs during embryonic development and cancer metastasis. During EMT, epithelial cells lose their polarity and cell-cell adhesion properties and acquire mesenchymal characteristics, including increased migratory capacity and invasiveness. Vimentin expression is upregulated during EMT, making it a potential target for therapeutic intervention in cancer.

In diagnostic pathology, vimentin immunostaining is used to identify mesenchymal cells and to distinguish them from epithelial cells. It can also be used to diagnose certain types of sarcomas and carcinomas that express vimentin.

Fibroblast Growth Factor 2 (FGF-2), also known as basic fibroblast growth factor, is a protein involved in various biological processes such as cell growth, proliferation, and differentiation. It plays a crucial role in wound healing, embryonic development, and angiogenesis (the formation of new blood vessels). FGF-2 is produced and secreted by various cells, including fibroblasts, and exerts its effects by binding to specific receptors on the cell surface, leading to activation of intracellular signaling pathways. It has been implicated in several diseases, including cancer, where it can contribute to tumor growth and progression.

Phosphopyruvate Hydratase is an enzyme also known as Enolase. It plays a crucial role in the glycolytic pathway, which is a series of reactions that occur in the cell to break down glucose into pyruvate, producing ATP and NADH as energy-rich intermediates.

Specifically, Phosphopyruvate Hydratase catalyzes the conversion of 2-phospho-D-glycerate (2-PG) to phosphoenolpyruvate (PEP), which is the second to last step in the glycolytic pathway. This reaction includes the removal of a water molecule from 2-PG, resulting in the formation of PEP and the release of a molecule of water.

The enzyme requires magnesium ions as a cofactor for its activity, and it is inhibited by fluoride ions. Deficiency or dysfunction of Phosphopyruvate Hydratase can lead to various metabolic disorders, including some forms of muscular dystrophy and neurodegenerative diseases.

The lateral ventricles are a pair of fluid-filled cavities located within the brain. They are part of the ventricular system, which is a series of interconnected spaces filled with cerebrospinal fluid (CSF). The lateral ventricles are situated in the left and right hemispheres of the brain and are among the largest of the ventricles.

Each lateral ventricle has a complex structure and can be divided into several parts:

1. Anterior horn: This is the front part of the lateral ventricle, located in the frontal lobe of the brain.
2. Body: The central part of the lateral ventricle, which is continuous with the anterior horn and posterior horn.
3. Posterior horn: The back part of the lateral ventricle, located in the occipital lobe of the brain.
4. Temporal horn: An extension that projects into the temporal lobe of the brain.

The lateral ventricles are lined with ependymal cells, which produce cerebrospinal fluid. CSF circulates through the ventricular system, providing buoyancy and protection to the brain, and is eventually absorbed into the bloodstream. Abnormalities in the size or shape of the lateral ventricles can be associated with various neurological conditions, such as hydrocephalus, brain tumors, or neurodegenerative diseases.

The ependyma is a type of epithelial tissue that lines the ventricular system of the brain and the central canal of the spinal cord. These cells are specialized glial cells that help to form the blood-brain barrier, regulate the cerebrospinal fluid (CSF) composition, and provide support and protection for the nervous tissue.

Ependymal cells have a cuboidal or columnar shape and possess numerous cilia on their apical surface, which helps to circulate CSF within the ventricles. They also have tight junctions that help to form the blood-brain barrier and prevent the passage of harmful substances from the blood into the CSF.

In addition to their role in maintaining the integrity of the CNS, ependymal cells can also differentiate into other types of cells, such as neurons and glial cells, under certain conditions. This property has made them a topic of interest in regenerative medicine and the study of neurodevelopmental disorders.

Uridine is a nucleoside that consists of a pyrimidine base (uracil) linked to a pentose sugar (ribose). It is a component of RNA, where it pairs with adenine. Uridine can also be found in various foods such as beer, broccoli, yeast, and meat. In the body, uridine can be synthesized from orotate or from the breakdown of RNA. It has several functions, including acting as a building block for RNA, contributing to energy metabolism, and regulating cell growth and differentiation. Uridine is also available as a dietary supplement and has been studied for its potential benefits in various health conditions.

Organ size refers to the volume or physical measurement of an organ in the body of an individual. It can be described in terms of length, width, and height or by using specialized techniques such as imaging studies (like CT scans or MRIs) to determine the volume. The size of an organ can vary depending on factors such as age, sex, body size, and overall health status. Changes in organ size may indicate various medical conditions, including growths, inflammation, or atrophy.

The colon, also known as the large intestine, is a part of the digestive system in humans and other vertebrates. It is an organ that eliminates waste from the body and is located between the small intestine and the rectum. The main function of the colon is to absorb water and electrolytes from digested food, forming and storing feces until they are eliminated through the anus.

The colon is divided into several regions, including the cecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum, and anus. The walls of the colon contain a layer of muscle that helps to move waste material through the organ by a process called peristalsis.

The inner surface of the colon is lined with mucous membrane, which secretes mucus to lubricate the passage of feces. The colon also contains a large population of bacteria, known as the gut microbiota, which play an important role in digestion and immunity.

A clone is a group of cells that are genetically identical to each other because they are derived from a common ancestor cell through processes such as mitosis or asexual reproduction. Therefore, the term "clone cells" refers to a population of cells that are genetic copies of a single parent cell.

In the context of laboratory research, cells can be cloned by isolating a single cell and allowing it to divide in culture, creating a population of genetically identical cells. This is useful for studying the behavior and characteristics of individual cell types, as well as for generating large quantities of cells for use in experiments.

It's important to note that while clone cells are genetically identical, they may still exhibit differences in their phenotype (physical traits) due to epigenetic factors or environmental influences.

Experimental liver neoplasms refer to abnormal growths or tumors in the liver that are intentionally created or manipulated in a laboratory setting for the purpose of studying their development, progression, and potential treatment options. These experimental models can be established using various methods such as chemical induction, genetic modification, or transplantation of cancerous cells or tissues. The goal of this research is to advance our understanding of liver cancer biology and develop novel therapies for liver neoplasms in humans. It's important to note that these experiments are conducted under strict ethical guidelines and regulations to minimize harm and ensure the humane treatment of animals involved in such studies.

'Tumor cells, cultured' refers to the process of removing cancerous cells from a tumor and growing them in controlled laboratory conditions. This is typically done by isolating the tumor cells from a patient's tissue sample, then placing them in a nutrient-rich environment that promotes their growth and multiplication.

The resulting cultured tumor cells can be used for various research purposes, including the study of cancer biology, drug development, and toxicity testing. They provide a valuable tool for researchers to better understand the behavior and characteristics of cancer cells outside of the human body, which can lead to the development of more effective cancer treatments.

It is important to note that cultured tumor cells may not always behave exactly the same way as they do in the human body, so findings from cell culture studies must be validated through further research, such as animal models or clinical trials.

Cytarabine is a chemotherapeutic agent used in the treatment of various types of cancer, including leukemias and lymphomas. Its chemical name is cytosine arabinoside, and it works by interfering with the DNA synthesis of cancer cells, which ultimately leads to their death.

Cytarabine is often used in combination with other chemotherapy drugs and may be administered through various routes, such as intravenous (IV) or subcutaneous injection, or orally. The specific dosage and duration of treatment will depend on the type and stage of cancer being treated, as well as the patient's overall health status.

Like all chemotherapy drugs, cytarabine can cause a range of side effects, including nausea, vomiting, diarrhea, hair loss, and an increased risk of infection. It may also cause more serious side effects, such as damage to the liver, kidneys, or nervous system, and it is important for patients to be closely monitored during treatment to minimize these risks.

It's important to note that medical treatments should only be administered under the supervision of a qualified healthcare professional, and this information should not be used as a substitute for medical advice.

Viral DNA refers to the genetic material present in viruses that consist of DNA as their core component. Deoxyribonucleic acid (DNA) is one of the two types of nucleic acids that are responsible for storing and transmitting genetic information in living organisms. Viruses are infectious agents much smaller than bacteria that can only replicate inside the cells of other organisms, called hosts.

Viral DNA can be double-stranded (dsDNA) or single-stranded (ssDNA), depending on the type of virus. Double-stranded DNA viruses have a genome made up of two complementary strands of DNA, while single-stranded DNA viruses contain only one strand of DNA.

Examples of dsDNA viruses include Adenoviruses, Herpesviruses, and Poxviruses, while ssDNA viruses include Parvoviruses and Circoviruses. Viral DNA plays a crucial role in the replication cycle of the virus, encoding for various proteins necessary for its multiplication and survival within the host cell.

Inbred strains of mice are defined as lines of mice that have been brother-sister mated for at least 20 consecutive generations. This results in a high degree of homozygosity, where the mice of an inbred strain are genetically identical to one another, with the exception of spontaneous mutations.

Inbred strains of mice are widely used in biomedical research due to their genetic uniformity and stability, which makes them useful for studying the genetic basis of various traits, diseases, and biological processes. They also provide a consistent and reproducible experimental system, as compared to outbred or genetically heterogeneous populations.

Some commonly used inbred strains of mice include C57BL/6J, BALB/cByJ, DBA/2J, and 129SvEv. Each strain has its own unique genetic background and phenotypic characteristics, which can influence the results of experiments. Therefore, it is important to choose the appropriate inbred strain for a given research question.

... releases gene silencing caused by DNA methylation. BrdU can also be used to identify microorganisms that ... Bromodeoxyuridine (5-bromo-2'-deoxyuridine, BrdU, BUdR, BrdUrd, broxuridine) is a synthetic nucleoside analogue with a chemical ... Hill BT, Baserga R (1975). "Effect of 5-bromodeoxyuridine on the transcriptional properties of the genome in WI-38 human ... Dolbeare, F (May 1995). "Bromodeoxyuridine: a diagnostic tool in biology and medicine, Part I: Historical perspectives, ...
A bromodeoxyuridine analysis". 226: 231-241. PMID 11023683. {{cite journal}}: Cite journal requires ,journal= (help) Rieger, R ...
Induced mutations on the molecular level can be caused by: Chemicals Hydroxylamine Base analogs (e.g., Bromodeoxyuridine (BrdU ...
Kuhn HG, Cooper-Kuhn CM (2007). "Bromodeoxyuridine and the detection of neurogenesis". Curr Pharmaceutical Biotechnol. 8 (3): ...
The effects of bromodeoxyuridine on cell differentiation (conversion of a primitive cell into a more specialized cell) were ... Weintraub, H; Campbell, GL; Holtzer, H (1972). "Identification of a developmental program using bromodeoxyuridine". J Mol Biol ...
During S-phase cells are treated with bromodeoxyuridine (BrdU) which is then incorporated into their nascent DNA, acting as a ... LAMBERT, BO; HANSSON, KERSTIN; LINDSTEN, JAN; STEN, MARGARETA; WERELIUS, BARBRO (12 February 2009). "Bromodeoxyuridine-induced ...
5' untranslated region (5'-UTR) 5-bromodeoxyuridine See bromodeoxyuridine. 5'-end One of two ends of a single linear strand of ... blunt end bromodeoxyuridine (BUDR, BrdU) Contents Top A B C D E F G H I J K L M N O P Q R S T U V W X Y Z See also References ...
5-Bromouracil Bromodeoxyuridine 5-bromouridine in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST ...
Effect of 5-bromodeoxyuridine on the hemolysin response in rabbits. Proc. Soc. Exp. Biol. Med., 124: 671-75. 1968 With W. H. ...
... based on incorporation of bromodeoxyuridine into single-stranded probes. The method was used to localise satellite repeats very ... Localisation of satellite DNA sequences on human metaphase chromosomes using bromodeoxyuridine-labelled probes. Chromosoma 97: ...
High-Frequency Activation in vitro by 5-Iododeoxyuridine and 5-Bromodeoxyuridine". Science. 174 (4005): 155-156. Bibcode: ...
"Identification of active oxalotrophic bacteria by Bromodeoxyuridine DNA labeling in a microcosm soil experiments". FEMS ...
... pulse-labeling chick embryos with bromodeoxyuridine". Journal of Neuroscience. 20 (21): 8021-8030. doi:10.1523/jneurosci.20-21- ...
Unlike the commonly used bromodeoxyuridine (BrdU), EdU detection requires no heat or acid treatment. EdU incorporated into DNA ...
Moss, Claire; Jackie Hunter, A.; Thorndyke, Michael C. (1998). "Patterns of bromodeoxyuridine incorporation and neuropeptide ...
Neural injections of Bromodeoxyuridine (BrdU) were applied to males of both groups to test for neurogenesis. Analysis showed ...
There it is detected with an ELISA technique: The wells are filled with a solution of a monoclonal antibody to bromo-deoxyuridine ... The DiviTum assay from Biovica International uses another thymidine analogue, bromodeoxyuridine, as substrate to the enzyme. ...
"Induction of Endogenous Virus and of Thymidline Kinase by Bromodeoxyuridine in Cell Cultures Transformed by Friend Virus" (PDF ... December 1974). "Induction of endogenous virus and of thymidine kinase by bromodeoxyuridine in cell cultures transformed by ...
This mitotic characteristic is how they are detected by adding Bromodeoxyuridine (BrdU) and staining with anti-BrdU. They have ...
Merrick CJ (December 2015). "Transfection with thymidine kinase permits bromodeoxyuridine labelling of DNA replication in the ...
Bromodeoxyuridine (BrdU) is another thymidine analog that is often used for the detection of proliferating cells in living ...
Hoechst 33342 and 33258 are quenched by bromodeoxyuridine (BrdU), which is commonly used to detect dividing cells. Hoechst ...
ICV injection of bromodeoxyuridine (BrdU) has been used to determine the effectiveness of this injection method compared to ... Examples of these studies include injection of bromodeoxyuridine for proliferation tracing, Apelin-13 for cerebral ischemia, ... "A comparative analysis of intraperitoneal versus intracerebroventricular administration of bromodeoxyuridine for the study of ...
The Giemsa staining was able to stain due to the presence of bromodeoxyuridine analogous base which was introduced to the ...
... bromodeoxyuridine) into the nascent DNA, then fluorescently detecting it. As replication forks spread bidirectionally from ...
... possibly due to inhibition by 5-bromodeoxyuridine and sodium butyrate. Yu, S; et al. (6 May 2017). "The T47D cell line is an ...
Thus, a cell lacking TK is resistant to bromodeoxyuridine (BrdU) and a cell lacking HGPRT is resistant to 6-thioguanine (6-TG) ...
... or parental DNA strands with a DNA label such as tritiated thymidine or bromodeoxyuridine (BrdU). These types of DNA labels ...
... which are induced by bromodeoxyuridine (BrdU) or distamycin A, an antibiotic that preferentially binds to AT-pairs of DNA. The ...
... of ROSA26 mice beta1-integrin bromodeoxyuridine c-kit (CD117) c-Met C1qR(p) END (CD105) PROM1 (CD133) ALCAM (CD166) ITGB1 (CD29 ...
Bromodeoxyuridine releases gene silencing caused by DNA methylation. BrdU can also be used to identify microorganisms that ... Bromodeoxyuridine (5-bromo-2-deoxyuridine, BrdU, BUdR, BrdUrd, broxuridine) is a synthetic nucleoside analogue with a chemical ... Hill BT, Baserga R (1975). "Effect of 5-bromodeoxyuridine on the transcriptional properties of the genome in WI-38 human ... Dolbeare, F (May 1995). "Bromodeoxyuridine: a diagnostic tool in biology and medicine, Part I: Historical perspectives, ...
Incorporation of 5-Bromodeoxyuridine into Low Molecular Weight Nuclear DNA INHIBITION OF MYOBLAST FUSION AFTER ONE ROUND OF DNA ... Tyrosine aminotransferase sensitivity to bromodeoxyuridine during restricted intervals of S phase in hepatoma cells. J C ... J C OBrien; Tyrosine aminotransferase sensitivity to bromodeoxyuridine during restricted intervals of S phase in hepatoma ... THE EFFECT OF 5-BROMODEOXYURIDINE ON DNA REPLICATION AND CELL DIVISION IN TETRAHYMENA PYRIFORMIS ...
Nucleic Acids, Nucleotides, and Nucleosides - Bromodeoxyuridine PubMed MeSh Term *Overview. Overview. subject area of * Basal ... TELOMERIC PROTEIN-DNA POINT CONTACTS IDENTIFIED BY PHOTO-CROSS-LINKING USING 5-BROMODEOXYURIDINE Journal Article ...
Monoclonal Mouse Anti-Bromodeoxyuridine, Clone Bu20a, Concentrated Antibody for Manual Use, Unconjugated, Culture supernatant, ...
Bromodeoxyuridine coupled to HGG (Human Gamma Globulin) Host: Sheep   ...
2.7 Bromodeoxyuridine (BrdU)/DNA: whole cell method *Culture conditions and equipment:. *250 mL culture flask wrapped in ... A Quantitative Method for Evaluating Bivariate Flow Cytometric Data Obtained Using Monoclonal Antibodies to Bromodeoxyuridine. ...
Bromodeoxyuridine (BrdU) Incorporation Assay. Proliferation was detected using the 5-Bromo-2′-deoxy-uridine Labeling and ...
Analyzing DNA replication III: Antibody labeling of incorporated bromodeoxyuridine (BrdU) in tissues and cells ... Analyzing DNA replication III: Antibody labeling of incorporated bromodeoxyuridine (BrdU) in tissues and cells ...
Bromodeoxyuridine * Cell Lineage / genetics * Cell Transformation, Neoplastic / genetics * Cells, Cultured * DNA Replication / ...
Treatment with sildenafil significantly (P,0.05) increased numbers of bromodeoxyuridine-immunoreactive cells in the ...
Bromodeoxyuridine/iododeoxyuridine labeling experiment.. For in vivo bromodeoxyuridine (BrdU)/iododeoxyuridine(IdU) labeling, ...
In our article in BMC Cancer [1] we modelled our graph for the passage of bromodeoxyuridine-labelled cells through the cell ... Erratum to: a method to estimate cell cycle time and growth fraction using bromodeoxyuridine-flow cytometry data from a single ... Erratum to: a method to estimate cell cycle time and growth fraction using bromodeoxyuridine-flow cytometry data from a single ... a method to estimate cell cycle time and growth fraction using bromodeoxyuridine-flow cytometry data from a single sample. BMC ...
BrdU indicates bromodeoxyuridine; FITC, fluorescein isothiocyanate; MCMV, murine cytomegalovirus; MFI, mean fluorescent ... BrdU indicates bromodeoxyuridine; FITC, fluorescein isothiocyanate; MCMV, murine cytomegalovirus; MFI, mean fluorescent ...
N2 - Background: 5-Bromodeoxyuridine is a radiosensitizing agent that is currently being evaluated in clinical trials as an ... AB - Background: 5-Bromodeoxyuridine is a radiosensitizing agent that is currently being evaluated in clinical trials as an ... Background: 5-Bromodeoxyuridine is a radiosensitizing agent that is currently being evaluated in clinical trials as an adjuvant ... abstract = "Background: 5-Bromodeoxyuridine is a radiosensitizing agent that is currently being evaluated in clinical trials as ...
Replication not inhibited by 5-bromodeoxyuridine. ,,,Click on the PDF icon to the left to view a copy of this virus entry in ...
Bromodeoxyuridine (BUdR), a potential radiosensitizing drug, was given by intravenous infusion at 650-1000 mg/m2/day for up to ... N2 - Bromodeoxyuridine (BUdR), a potential radiosensitizing drug, was given by intravenous infusion at 650-1000 mg/m2/day for ... AB - Bromodeoxyuridine (BUdR), a potential radiosensitizing drug, was given by intravenous infusion at 650-1000 mg/m2/day for ... Morstyn, G, Kinsella, T, Shan, CSK, Whang-Peng, J, Russo, A & Mitchell, JB 1985, In vivo incorporation of bromodeoxyuridine ...
Bromodeoxyuridine labeling and histomorphometry. To document cell proliferation from the acute phase of the disease into the ...
Azad Bonni, Harvard Medical School, Boston, MA), anti-tubulin βIII (1:500; Sigma), rat anti-bromodeoxyuridine (1:400; Axyll), ...
Bromodeoxyuridine and the detection of neurogenesis. Hans-Georg Kuhn, Christiana M Cooper-Kuhn Current pharmaceutical ...
Identification of active oxalotrophic bacteria by Bromodeoxyuridine DNA labeling in a microcosm soil experiments. FEMS ... Artursson, V. & Jansson, J. K. Use of Bromodeoxyuridine immunocapture to identify active bacteria associated with Arbuscular ... Active microorganisms have been identified previously using stable isotope probing (SIP) or bromodeoxyuridine (BrdU) labeling. ...
Radiosensitization with carotid intra-arterial bromodeoxyuridine +/- 5-fluorouracil biomodulation for malignant gliomas. ...
... one hour after injection with Bromodeoxyuridine (BrdU, 12 mg/kg). Muscle samples were collected and myogenic cells were ... Incorporation of Bromodeoxyuridine (BrdU) into newly synthesized DNA was used to identify proliferating cells in muscle tissue ... one hour after injection with Bromodeoxyuridine (BrdU, 12 mg/kg). Muscle samples were collected and myogenic cells were ...
Bromodeoxyuridine (BrdU) immunocytochemistry and flow cytometry were applied to detect the proliferation of VSMCs. miRNA ... Bromodeoxyuridine (BrdU) immunocytochemistry and flow cytometry were applied to detect the proliferation of VSMCs. miRNA ...
Interstrand cross-links: a new type of gamma ray damage in bromodeoxyuridine substituted DNA. Biochemistry, 44, 1932-1940 (2005 ... Interstrand cross-link induction by UV radiation in bromodeoxyuridine substituted DNA: dependence on DNA conformation. ...
Identification of active oxalotrophic bacteria by bromodeoxyuridine DNA-labeling in a microcosm soil experiment. FEMS ...
Bromodeoxyuridine/diagnostic use; Cell Nucleus/*physiology/ultrastructure; Cell Physiological Phenomena; Chromatin/physiology/ ...
Measurement of Bromodeoxyuridine Labeling Index, Ki-67 Score and Ag- NOR Count in Breast Carcinomas: Comparison with DNA Ploidy ... Application of Bromodeoxyuridine (BrdU) and Anti-BrdU Monoclonal Antibody for the in vivo Analysis of Proliferative ... However, no significant correlation was obtained between the number of Ag-NORs and the bromodeoxyuridine-labeling indices (r = ...
Adult neurogenesis is often studied by labeling new cells with the thymidine analog bromodeoxyuridine (BrdU) and using ... Adult neurogenesis is often studied by labeling new cells with the thymidine analog bromodeoxyuridine (BrdU) and using ...
bromodeoxyuridine triphosphate. CA3. chromomycin A3. CD. cluster of differentiation. CFDA SE. carboxyfluorescein diacetate, ...
  • Bromodeoxyuridine (5-bromo-2'-deoxyuridine, BrdU, BUdR, BrdUrd, broxuridine) is a synthetic nucleoside analogue with a chemical structure similar to thymidine. (wikipedia.org)
  • Active microorganisms have been identified previously using stable isotope probing (SIP) or bromodeoxyuridine (BrdU) labeling. (nature.com)
  • Twelve piglets per group were slaughtered at 5, 12 and 26 dpn, one hour after injection with Bromodeoxyuridine (BrdU, 12 mg/kg). (nature.com)
  • Bromodeoxyuridine (BrdU) immunocytochemistry and flow cytometry were applied to detect the proliferation of VSMCs. (hindawi.com)
  • The lungs were examined following a single injection of bromodeoxyuridine (BrdU) 2 h prior to necropsy. (cdc.gov)
  • Bromodeoxyuridine (BrdU) is a synthetic analogue of thymidine, one of the building blocks of DNA. (vetscite.org)
  • to OECD TG 442B and GLP, the skin sensitising potential of 2-ethoxyethyl (2Z)-2-cyano-2-[3-(3-methoxypropylamino)cyclohex-2-en-1-ylidene]acetate (C-1701 B_C_3) in female CBA/J mice was evaluated using the non-radioactive local lymph node assay (Ina Research Inc. (2012), 58V0473111X188), which assess BrdU incorporation as a measure of lymphocyte proliferation. (europa.eu)
  • On day 5, Bromodeoxyuridine (BrdU) was administered intraperitoneally (i.p.) to all animals at a dose level of 5 mg/animal. (europa.eu)
  • Bromodeoxyuridine (BrdU) staining assays revealed that HPSE-LV-Glu30 cell growth was significantly lower than in the Con-LV-Glu30 and Glu30 groups. (molvis.org)
  • Bromodeoxyuridine (BrdU) incorporation assay and migration studies were performed to elucidate antiproliferative activity of the drug, if any. (jcimjournal.com)
  • The bromodeoxyuridine (BrdU) Uptake assay follows a similar approach to measuring cell proliferation as 3H-Thymadine Incorporation assay, except BrdU becomes incorporated into replicating DNA in place of 3H-TdR and immunohistochemistry techniques are used for detection. (cytologicsbio.com)
  • Synchronized hepatoma tissue culture (HTC) cells, accumulated at the G1/S boundary with aminopterin, were released into S phase with either thymidine or 5-bromodeoxyuridine (BUdR). (rupress.org)
  • The traditional proliferation assays of thymidine incorporation and bromodeoxyuridine uptake measure DNA synthesis, whereas other assays measure ATP concentration, metabolic activity and other factors. (cytologicsbio.com)
  • However, no significant correlation was obtained between the number of Ag-NORs and the bromodeoxyuridine-labeling indices (r =0.2064). (karger.com)
  • Bromodeoxyuridine (BUdR), a potential radiosensitizing drug, was given by intravenous infusion at 650-1000 mg/m2/day for up to 12 days. (tmu.edu.tw)
  • We used 3-(4,5-dimethylthiahiazol-2-y1)-2,5-diphenyltetrazolium bromide and bromodeoxyuridine staining assays to determine that effects of heparanase expression on human retinal vascular endothelial cell proliferation. (molvis.org)
  • Replication not inhibited by 5-bromodeoxyuridine. (cdc.gov)
  • The kinetics of replication and transcription (monitored by immunolabelling after incorporating bromodeoxyuridine or bromouridine) reveal that each genome replicates independently of others in a focus, and that newly-made RNA remains in a focus (residence half-time ~43 min) long after it has been made. (biomedcentral.com)
  • Johansson MC, Baldetorp B, Bendahl PO, Johansson R, Oredsson SM: An improved mathematical method to estimate DNA synthesis time of bromodeoxyuridine-labelled cells, using FCM-derived data. (biomedcentral.com)
  • Tyrosine aminotransferase sensitivity to bromodeoxyuridine during restricted intervals of S phase in hepatoma cells. (rupress.org)
  • En face co-immunostaining of the mouse aortic arch revealed a low level of PDCD4 in endothelial cells undergoing pulsatile shear stress. (plos.org)
  • 0.05) increased numbers of bromodeoxyuridine-immunoreactive cells in the subventricular zone and the dentate gyrus and numbers of immature neurons, as indicated by betaIII-tubulin (TuJ1) immunoreactivity in the ipsilateral subventricular zone and striatum. (nih.gov)
  • In our article in BMC Cancer [ 1 ] we modelled our graph for the passage of bromodeoxyuridine-labelled cells through the cell cycle presented in Figure 1 on the figure published by Johansson et al. (biomedcentral.com)
  • 13. Newmark P.A., Sanchez Alvarado A. (2000) Bromodeoxyuridine specifically labels the regenerative stem cells of planarians. (medline.ru)
  • Agyrophilic nucleolar organizer region counts as related to bromodeoxyuridine incorporation scores in ovarian clear cell carcinoma cells]. (bvsalud.org)
  • Tumors were fixed in either Carnoy's or formalin fixative sectioned and digested in 20 μg/ml proteinase K. For bromodeoxyuridine staining areas had been treated with monoclonal antibodies to 5′-bromodeoxyuridine (21). (sciencepop.org)
  • Animals had been treated with bromodeoxyuridine 3 hr ahead of sacrifice. (sciencepop.org)
  • Eidukevicius R, Characiejus D, Janavicius R, Kazlauskaite N, Pasukoniene V, Mauricas M, Den Otter W: A method to estimate cell cycle time and growth fraction using bromodeoxyuridine-flow cytometry data from a single sample. (biomedcentral.com)
  • Based on the study results, 2-ethoxyethyl (2Z)-2-cyano-2-[3-(3-methoxypropylamino)cyclohex-2-en-1-ylidene]acetate (C-1701 B_C_3) was considered not to possess any skin sensitising potential under the experimental conditions employed. (europa.eu)
  • We investigated the effects of DNA secondary structure and O 2 on the induction of direct strand breaks in 5-bromodeoxyuridine-containing oligonucleotides. (nau.edu)
  • 10. Combined flow cytometry and immunohistochemistry analyses for the assessment of nasopharyngeal carcinoma cell kinetics by in vivo bromodeoxyuridine infusion. (nih.gov)
  • In vivo bromodeoxyuridine incorporation in normal mouse kidney: immunohistochemical detection and measurement of labeling indices. (bdbiosciences.com)
  • In vivo evaluation by bromodeoxyuridine incorporation and flow cytometry. (nih.gov)
  • The effect of lycopene-based agents on prostate cancer growth and survival were examined using proliferation assays, bromodeoxyuridine incorporation and flow cytometric analysis of cellular DNA content. (nih.gov)
  • Dover R, and Patel K. Improved methodology for detecting bromodeoxyuridine in cultured cells and tissue sections by immunocytochemistry. (bdbiosciences.com)
  • Flow cytometric measurement of total DNA content and incorporated bromodeoxyuridine. (bdbiosciences.com)
  • Bromodeoxyuridine releases gene silencing caused by DNA methylation. (wikipedia.org)
  • 4. Cell kinetics of human ovarian cancer with in vivo administration of bromodeoxyuridine. (nih.gov)
  • Replication not inhibited by 5-bromodeoxyuridine. (cdc.gov)