Quaternary ammonium analog of ethidium; an intercalating dye with a specific affinity to certain forms of DNA and, used as diiodide, to separate them in density gradients; also forms fluorescent complexes with cholinesterase which it inhibits.
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.
A protein of the annexin family isolated from human PLACENTA and other tissues. It inhibits cytosolic PHOSPHOLIPASE A2, and displays anticoagulant activity.
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.
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.
Chemicals and substances that impart color including soluble dyes and insoluble pigments. They are used in INKS; PAINTS; and as INDICATORS AND REAGENTS.
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.
The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.
The pathological process occurring in cells that are dying from irreparable injuries. It is caused by the progressive, uncontrolled action of degradative ENZYMES, leading to MITOCHONDRIAL SWELLING, nuclear flocculation, and cell lysis. It is distinct it from APOPTOSIS, which is a normal, regulated cellular process.
Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.
A short pro-domain caspase that plays an effector role in APOPTOSIS. It is activated by INITIATOR CASPASES such as CASPASE 9. Isoforms of this protein exist due to multiple alternative splicing of its MESSENGER RNA.
A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
Splitting the DNA into shorter pieces by endonucleolytic DNA CLEAVAGE at multiple sites. It includes the internucleosomal DNA fragmentation, which along with chromatin condensation, are considered to be the hallmarks of APOPTOSIS.
Organic or inorganic compounds that contain the -N3 group.
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.
A benzimidazole antifilarial agent; it is fluorescent when it binds to certain nucleotides in DNA, thus providing a tool for the study of DNA replication; it also interferes with mitosis.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A trypanocidal agent and possible antiviral agent that is widely used in experimental cell biology and biochemistry. Ethidium has several experimentally useful properties including binding to nucleic acids, noncompetitive inhibition of nicotinic acetylcholine receptors, and fluorescence among others. It is most commonly used as the bromide.
A cell line derived from cultured tumor cells.
The voltage difference, normally maintained at approximately -180mV, across the INNER MITOCHONDRIAL MEMBRANE, by a net movement of positive charge across the membrane. It is a major component of the PROTON MOTIVE FORCE in MITOCHONDRIA used to drive the synthesis of ATP.
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.
A family of intracellular CYSTEINE ENDOPEPTIDASES that play a role in regulating INFLAMMATION and APOPTOSIS. They specifically cleave peptides at a CYSTEINE amino acid that follows an ASPARTIC ACID residue. Caspases are activated by proteolytic cleavage of a precursor form to yield large and small subunits that form the enzyme. Since the cleavage site within precursors matches the specificity of caspases, sequential activation of precursors by activated caspases can occur.
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.
PHENOTHIAZINES with an amino group at the 3-position that are green crystals or powder. They are used as biological stains.
All of the processes involved in increasing CELL NUMBER including CELL DIVISION.
The type species of the genus NITROSOMONAS, a gram-negative chemolithotroph that oxidizes ammonia to nitrite. It is found in soil, sewage, freshwater, and on building walls, and especially in polluted areas where air contains high levels of nitrogen compounds.
Fluorescent probe capable of being conjugated to tissue and proteins. It is used as a label in fluorescent antibody staining procedures as well as protein- and amino acid-binding techniques.
Quinolinium compounds are organic salts formed by the protonation of quinoline, characterized by a positively charged nitrogen atom surrounded by an aromatic ring, which have been used in various applications including as antimicrobial agents and chemical research.
The relationship between the dose of an administered drug and the response of the organism to the drug.
An enzyme that catalyzes the hydrolysis of ACETYLCHOLINE to CHOLINE and acetate. In the CNS, this enzyme plays a role in the function of peripheral neuromuscular junctions. EC 3.1.1.7.
The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.
A tetrameric enzyme that, along with the coenzyme NAD+, catalyzes the interconversion of LACTATE and PYRUVATE. In vertebrates, genes for three different subunits (LDH-A, LDH-B and LDH-C) exist.
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
Membrane proteins encoded by the BCL-2 GENES and serving as potent inhibitors of cell death by APOPTOSIS. The proteins are found on mitochondrial, microsomal, and NUCLEAR MEMBRANE sites within many cell types. Overexpression of bcl-2 proteins, due to a translocation of the gene, is associated with follicular lymphoma.
The process by which semen is kept viable outside of the organism from which it was derived (i.e., kept from decay by means of a chemical agent, cooling, or a fluid substitute that mimics the natural state within the organism).
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a serine moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and serine and 2 moles of fatty acids.
A sulfur-containing analog of butyrylcholine which is hydrolyzed by butyrylcholinesterase to butyrate and thiocholine. It is used as a reagent in the determination of butyrylcholinesterase activity.
Elements of limited time intervals, contributing to particular results or situations.
A rapid-onset, short-acting cholinesterase inhibitor used in cardiac arrhythmias and in the diagnosis of myasthenia gravis. It has also been used as an antidote to curare principles.
A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
A scanning microscope-based, cytofluorimetry technique for making fluorescence measurements and topographic analysis on individual cells. Lasers are used to excite fluorochromes in labeled cellular specimens. Fluorescence is detected in multiple discrete wavelengths and the locational data is processed to quantitatively assess APOPTOSIS; PLOIDIES; cell proliferation; GENE EXPRESSION; PROTEIN TRANSPORT; and other cellular processes.
Mature male germ cells derived from SPERMATIDS. As spermatids move toward the lumen of the SEMINIFEROUS TUBULES, they undergo extensive structural changes including the loss of cytoplasm, condensation of CHROMATIN into the SPERM HEAD, formation of the ACROSOME cap, the SPERM MIDPIECE and the SPERM TAIL that provides motility.
Phenanthridines are a class of heterocyclic aromatic organic compounds consisting of two benzene rings fused to a pyridine ring, which have been extensively studied for their biological activities, including antimalarial, antibacterial, and antitumor properties.
Rendering pathogens harmless through the use of heat, antiseptics, antibacterial agents, etc.
Established cell cultures that have the potential to propagate indefinitely.
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.
The degree of replication of the chromosome set in the karyotype.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
A technique in which electric pulses of intensity in kilovolts per centimeter and of microsecond-to-millisecond duration cause a temporary loss of the semipermeability of CELL MEMBRANES, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA.
A large plant genus of the family EUPHORBIACEAE, order Euphorbiales, subclass Rosidae. They have a milky sap and a female flower consisting of a single pistil, surrounded by numerous male flowers of one stamen each. Euphorbia hirta is rarely called milkweed but that name is normally used for ASCLEPIAS.
Quaternary salts derived from tetrazoles. They are used in tests to distinguish between reducing sugars and simple aldehydes, for detection of dehydrogenase in tissues, cells, and bacteria, for determination of corticosteroids, and in color photography. (From Mall's Dictionary of Chemistry, 5th ed, p455)
A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.
A versatile red dye used in cosmetics, pharmaceuticals, textiles, etc., and as tissue stain, vital stain, and counterstain with HEMATOXYLIN. It is also used in special culture media.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
Molecules or ions formed by the incomplete one-electron reduction of oxygen. These reactive oxygen intermediates include SINGLET OXYGEN; SUPEROXIDES; PEROXIDES; HYDROXYL RADICAL; and HYPOCHLOROUS ACID. They contribute to the microbicidal activity of PHAGOCYTES, regulation of signal transduction and gene expression, and the oxidative damage to NUCLEIC ACIDS; PROTEINS; and LIPIDS.
A member of the Bcl-2 protein family and homologous partner of C-BCL-2 PROTO-ONCOGENE PROTEIN. It regulates the release of CYTOCHROME C and APOPTOSIS INDUCING FACTOR from the MITOCHONDRIA. Several isoforms of BCL2-associated X protein occur due to ALTERNATIVE SPLICING of the mRNA for this protein.
A fluorescent probe with low toxicity which is a potent substrate for P-glycoprotein and the bacterial multidrug efflux transporter. It is used to assess mitochondrial bioenergetics in living cells and to measure the efflux activity of P-glycoprotein in both normal and malignant cells. (Leukemia 1997;11(7):1124-30)

Binding of annexin V to plasma membranes of human spermatozoa: a rapid assay for detection of membrane changes after cryostorage. (1/576)

When the cell membrane is disturbed, phospholipid phosphatidylserine (PS) is translocated from the inner to the outer leaflet of the plasma membrane. This is one of the earliest signs of apoptosis and can be monitored by the calcium-dependent binding of annexin V. Therefore, annexin V-binding, in conjunction with flow cytometry, was used to evaluate the integrity of the sperm plasma membrane after different cryostorage protocols: i.e. 10% (v/v) glycerol; sperm maintenance medium (MM); freezing medium TEST yolk buffer (TYB); or cryostorage without protection (cryoshock). Using a combination of two fluorescent dyes, annexin V and propidium iodide (PI), led to three groups of spermatozoa being identified: (i) viable spermatozoa (annexin V-negative and PI-negative); (ii) dead spermatozoa (annexin V-positive and PI-positive); and (iii) cells with impaired but integer plasma membrane (annexin V-positive and PI-negative). The percentage of vital annexin V-negative spermatozoa increased significantly (P < 0.05) from spermatozoa treated by cryoshock (15.0+/-1.2%) to spermatozoa cryopreserved by TYB (26.6+/-2.2%) via cryopreservation by 10% (v/v) glycerol (19.9+/-1.6%) and by MM (22.2 1.8%) and was associated with the percentage of motile spermatozoa (17.6+/-3.4% by glycerol; 19.6+/-3.7% by MM and 22.6+/-3.9% by TYB; P = 0.0001). Of the spermatozoa, 12-22% were annexin V-positive even though they did not bind to PI, indicating viability before as well as after cryostorage. The percentage of vital annexin V-positive spermatozoa was significantly correlated with different sperm motility parameters (velocity straight linear, r = 0.601, P = 0.018; percentage of linearly motile spermatozoa: r = 0.549, P = 0.034). We, therefore, concluded that annexin V-binding is more sensitive in detecting a deterioration of membrane functions than PI staining, and that a considerable percentage of spermatozoa might have dysfunctional plasma membranes besides dead or moribund cells. Of the cryopreservation protocols tested, TYB yielded the most viable spermatozoa. Therefore, we advocate the use of the annexin V-binding assay for the evaluation of the quality and integrity of spermatozoa.  (+info)

Organophosphorylation of acetylcholinesterase in the presence of peripheral site ligands. Distinct effects of propidium and fasciculin. (2/576)

Structural analysis of acetylcholinesterase (AChE) has revealed two sites of ligand interaction in the active site gorge: an acylation site at the base of the gorge and a peripheral site at its mouth. A goal of our studies is to understand how ligand binding to the peripheral site alters the reactivity of substrates and organophosphates at the acylation site. Kinetic rate constants were determined for the phosphorylation of AChE by two fluorogenic organophosphates, 7-[(diethoxyphosphoryl)oxy]-1-methylquinolinium iodide (DEPQ) and 7-[(methylethoxyphosphonyl)oxy]-4-methylcoumarin (EMPC), by monitoring release of the fluorescent leaving group. Rate constants obtained with human erythrocyte AChE were in good agreement with those obtained for recombinant human AChE produced from a high level Drosophila S2 cell expression system. First-order rate constants kOP were 1,600 +/- 300 min-1 for DEPQ and 150 +/- 11 min-1 for EMPC, and second-order rate constants kOP/KOP were 193 +/- 13 microM-1 min-1 for DEPQ and 0.7-1.0 +/- 0.1 microM-1 min-1 for EMPC. Binding of the small ligand propidium to the AChE peripheral site decreased kOP/KOP by factors of 2-20 for these organophosphates. Such modest inhibitory effects are consistent with our recently proposed steric blockade model (Szegletes, T., Mallender, W. D., and Rosenberry, T. L. (1998) Biochemistry 37, 4206-4216). Moreover, the binding of propidium resulted in a clear increase in kOP for EMPC, suggesting that molecular or electronic strain caused by the proximity of propidium to EMPC in the ternary complex may promote phosphorylation. In contrast, the binding of the polypeptide neurotoxin fasciculin to the peripheral site of AChE dramatically decreased phosphorylation rate constants. Values of kOP/KOP were decreased by factors of 10(3) to 10(5), and kOP was decreased by factors of 300-4,000. Such pronounced inhibition suggested a conformational change in the acylation site induced by fasciculin binding. As a note of caution to other investigators, measurements of phosphorylation of the fasciculin-AChE complex by AChE inactivation gave misleading rate constants because a small fraction of the AChE was resistant to inhibition by fasciculin.  (+info)

In vitro cell cycle arrest, in vivo action on solid metastasizing tumors, and host toxicity of the antimetastatic drug NAMI-A and cisplatin. (3/576)

The effects of NAMI-A (imidazolium trans-imidazoledimethyl sulfoxide-tetrachlororuthenate) are compared with cisplatin on tumor cells cultured in vitro at doses of 1 to 100 microM and on tumor metastases in vivo at maximum tolerated doses. Using mouse tumors that metastasize to the lungs, NAMI-A given i.p. for 6 consecutive days at 35 mg/kg/day, was effective independently of the tumor line being treated and of the stage of metastasis growth. Conversely, cisplatin (2 mg/kg/day for 6 days) was as effective as NAMI-A on MCa mammary carcinoma and TS/A adenocarcinoma and less effective than NAMI-A on Lewis lung carcinoma. Cisplatin reduced body weight gain and spleen weight during treatment and was much more toxic than NAMI-A on liver sinusoids, kidney tubules, and lung epithelium. In vitro NAMI-A caused a transient cell cycle arrest of tumor cells in the premitotic G2/M phase, whereas cisplatin caused a progressive dose-dependent disruption of cell cycle phases. Correspondingly, NAMI-A did not modify cell growth, whereas cisplatin caused a dose-dependent reduction of cell proliferation, as determined by sulforhodamine B test. Thus, NAMI-A, unlike cisplatin, is a potent agent for the treatment of solid tumor metastases as well as when these tumor lesions are in an advanced stage of growth. NAMI-A is endowed with a mechanism of action unrelated to direct tumor cell cytotoxicity, and such mechanism of action is responsible for a reduced host toxicity.  (+info)

Time courses of mammalian cell electropermeabilization observed by millisecond imaging of membrane property changes during the pulse. (4/576)

Time courses of electropermeabilization were analyzed during the electric field application using a rapid fluorescent imaging system. Exchanges of calcium ions through electropermeabilized membrane of Chinese hamster ovary cells were found to be asymmetrical. Entry of calcium ions during a millisecond pulse occurred on the anode-facing cell hemisphere. Entry through the region facing the cathode was observed only after the pulse. Leakage of intracellular calcium ions from electropermeabilized cell in low-calcium content medium was observed only from the anode-facing side. The exchanges during the pulse were mostly due to diffusion-driven processes, i.e., governed by the concentration gradient. Interaction of propidium iodide, a dye sensitive to the structural alteration of membrane, with cell membrane was asymmetrical during electropermeabilization. Localized enhancement of the dye fluorescence was observed during and after the pulsation on the cell surface. Specific staining of a limited anode-facing part of the membrane was observed as soon as the pulse was applied. The membrane fluorescence level increased during and immediately after the pulse whereas the geometry of the staining was unchanged. The membrane regions stained by propidium iodide were the same as those where calcium exchanges occurred. The fraction of the membrane on which structural alterations occurred was defined by the field strength. The density of defects was governed by the pulse duration. Electropermeabilization is a localized but asymmetrical process. The membrane defects are created unequally on the two cell sides during the pulse, implying a vectorial effect of the electric field on the membrane.  (+info)

LY303366 exhibits rapid and potent fungicidal activity in flow cytometric assays of yeast viability. (5/576)

LY303366 is a semisynthetic analog of the antifungal lipopeptide echinocandin B that inhibits (1,3)-beta-D-glucan synthase and exhibits efficacy in animal models of human fungal infections. In this study, we utilized flow cytometric analysis of propidium iodide uptake, single-cell sorting, and standard microbiological plating methods to study the antifungal effect of LY303366 on Saccharomyces cerevisiae and Candida albicans. Our data indicate that an initial 5-min pulse treatment with LY303366 caused yeasts to take up propidium iodide and lose their ability to grow. Amphotericin B and cilofungin required longer exposure periods (30 and 180 min, respectively) and higher concentrations to elicit these fungicidal effects. These two measurements of fungicidal activity by LY303366 were highly correlated (r > 0.99) in concentration response and time course experiments. As further validation, LY303366-treated yeasts that stained with propidium iodide were unable to grow in single-cell-sorted cultures. Our data indicate that LY303366 is potent and rapidly fungicidal for actively growing yeasts. The potency and rapid action of this new fungicidal compound suggest that LY303366 may be useful for antifungal therapy.  (+info)

Excimer laser-induced hydroxyl radical formation and keratocyte death in vitro. (6/576)

PURPOSE: To characterize the type of reactive oxygen species (ROS) produced by excimer photoablation of aqueous solutions and to show the effects of ROS and antioxidants on corneal stromal cells in vitro. METHODS: Electron spin-resonance spectroscopy was performed using the spin-trapping agent 5,5-dimethyl-1-pyrroline N-oxide (DMPO) for the detection of the superoxide anion and the hydroxyl radical in an acellular DMPO solution irradiated with the excimer laser. Hydroxyl radicals were produced by the Fenton reaction in vitro by the mixture of hydrogen peroxide and ferrous iron (Fe2+), and the effects on cultured corneal fibroblasts were observed by fluorescent microscopy using the cell death marker, propidium iodide (PI) and TdT-mediated dUTP nick-end labeling (TUNEL). RESULTS: Excimer photoablation of a 1% DMPO solution produced a species-specific spin-trapping adduct for the hydroxyl radical ('OH), but not for the superoxide anion or other unidentified free radical. The signals were inhibited dose dependently by the hydroxyl radical scavenger dimethylsulfoxide (DMSO) and an L-ascorbic acid analogue, EPCK-1. The production of *OH in the supernatant of cultured rabbit corneal fibroblasts by the Fenton reaction caused an increase in PI (+) and TUNEL (+) cells by 90 minutes, which was significantly inhibited by the addition of DMSO. CONCLUSIONS: Hydroxyl radicals may be partly responsible for stromal fibroblast cell apoptosis after excimer photoablation.  (+info)

Effects of commercial glucose-based peritoneal dialysates on peripheral blood phagocytes apoptosis. (7/576)

BACKGROUND: Variable glucose-lactate-based peritoneal dialysates have negative effects on peritoneal macrophages and peripheral blood leukocytes, reducing the capacity of leukocytes for chemotaxis, bacterial killing. But few reports exist on cell apoptosis. To investigate the effects of glucose-lactate-based peritoneal dialysates on cultured phagocytes (monocytes and neutrophils), we focused on studying phagocyte apoptosis after brief exposure to commercial peritoneal dialysates. METHODS: Cell apoptosis is measured by flow cytometry (FCM) to detect phosphatidylserine (PS) exposure on early apoptotic cells using fluorescein-labeled annexin V. To mimic the composition of dialysate in vivo, where the freshly instilled solution mixes with the residual dialysate from the previous cycle, we performed the experiments using a mixture of fresh and spent dialysate (9:1). In our transient exposure experiments, monocytes and neutrophils were separately incubated in each of the test solutions (1.5% glucose and 4.25% glucose dialysates) for 10 minutes or 30 minutes and afterward separated and resuspended in RPMI 1640 medium and cultured over the indicated time. RESULTS: After exposure to 1.5% glucose dialysates for 10 minutes, monocytes and neutrophils exhibited normally spontaneous apoptosis. After exposure to 4.25% glucose dialysate, monocytes underwent apoptosis increasingly, 21%+/-5.0% versus 9.8%+/-3.6% (p < 0.05) at 24 hours and 47%+/-6.2% versus 16%+/-4.0% (p < 0.01) at 72 hours compared with controls. For neutrophils, the results were discouraging: hypertonic dialysate not only increased apoptosis [65.36%+/-2.6% versus 34.17% +/-8.52% (p < 0.01) at 72 hours], but also induced cell necrosis. When Incubation time was prolonged for 30 minutes, 1.5% dialysate acted like 4.25% dialysate, with the rate of apoptosis increasing rapidly [40%+/-4.0% versus 16%+/-4.0% (p < 0.01) at 72 hours for monocytes, and 66.90%+/-5.6% versus 34.17%+/-8.52% (p < 0.01) at 72 hours for neutrophils]. CONCLUSION: Glucose-lactate-based peritoneal dialysates can induce peripheral blood phagocyte apoptosis in vitro, which indicates that glucose plays an important role in triggering cell apoptosis. Therefore, looking for new, physiologic peritoneal dialysis fluids to replace conventional fluids is reasonable.  (+info)

CD28, IL-2-independent costimulatory pathways for CD8 T lymphocyte activation. (8/576)

We investigate, here, the mechanism of the costimulatory signals for CD8 T cell activation and confirm that costimulation signals via CD28 do not appear to be required to initiate proliferation, but provide survival signals for CD8 T cells activated by TCR ligation. We show also that IL-6 and TNF-alpha can provide alternative costimulatory survival signals. IL-6 and TNF-alpha costimulate naive CD8 T cells cultured on plate-bound anti-CD3 in the absence of CD28 ligation. They act directly on sorted CD8-positive T cells. They also costimulate naive CD8 T cells from Rag-2-deficient mice, bearing transgenic TCRs for HY, which lack memory cells, a potential source of IL-2 secretion upon activation. IL-6 and TNF-alpha provide costimulation to naive CD8 T cells from CD28, IL-2, or IL-2Ralpha-deficient mice, and thus function in the absence of the B7-CD28 and IL-2 costimulatory pathways. The CD8 T cell generated via the anti-CD3 plus IL-6 and TNF-alpha pathway have effector function in that they express strong cytolytic activity on Ag-specific targets. They secrete only very small amounts of any of the cytokines tested upon restimulation with peptide-loaded APC. The ability of the naive CD8 T cells to respond to TCR ligation and costimulatory signals from IL-6 and TNF-alpha provides a novel pathway that can substitute for signals from CD4 helper cells or professional APC. This may be significant in the response to viral Ags, which can be potentially expressed on the surface of any class I MHC-expressing cell.  (+info)

Propidium is not a medical condition or diagnosis, but rather it is a fluorescent dye that is used in medical and scientific research. It is often used in procedures such as flow cytometry and microscopy to stain and label cells or nucleic acids (DNA or RNA). Propidium iodide is the most commonly used form of propidium, which binds to DNA by intercalating between the bases.

Once stained with propidium iodide, cells with damaged membranes will take up the dye and can be detected and analyzed based on their fluorescence intensity. This makes it possible to identify and quantify dead or damaged cells in a population, as well as to analyze DNA content and cell cycle status.

Overall, propidium is an important tool in medical research and diagnostics, providing valuable information about cell health, viability, and genetic material.

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).

Annexin A5 is a protein that belongs to the annexin family, which are calcium-dependent phospholipid-binding proteins. Annexin A5 has high affinity for phosphatidylserine, a type of phospholipid that is usually located on the inner leaflet of the plasma membrane in healthy cells. However, when cells undergo apoptosis (programmed cell death), phosphatidylserine is exposed on the outer leaflet of the plasma membrane.

Annexin A5 can bind to exposed phosphatidylserine on the surface of apoptotic cells and is commonly used as a marker for detecting apoptosis in various experimental settings, including flow cytometry, immunohistochemistry, and imaging techniques. Annexin A5-based assays are widely used in research and clinical settings to study the mechanisms of apoptosis and to develop diagnostic tools for various diseases, such as cancer, neurodegenerative disorders, and cardiovascular diseases.

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.

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.

Coloring agents, also known as food dyes or color additives, are substances that are added to foods, medications, and cosmetics to improve their appearance by giving them a specific color. These agents can be made from both synthetic and natural sources. They must be approved by regulatory agencies such as the U.S. Food and Drug Administration (FDA) before they can be used in products intended for human consumption.

Coloring agents are used for various reasons, including:

* To replace color lost during food processing or preparation
* To make foods more visually appealing
* To help consumers easily identify certain types of food
* To indicate the flavor of a product (e.g., fruit-flavored candies)

It's important to note that while coloring agents can enhance the appearance of products, they do not affect their taste or nutritional value. Some people may have allergic reactions to certain coloring agents, so it's essential to check product labels if you have any known allergies. Additionally, excessive consumption of some synthetic coloring agents has been linked to health concerns, so moderation is key.

'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.

Cell death is the process by which cells cease to function and eventually die. There are several ways that cells can die, but the two most well-known and well-studied forms of cell death are apoptosis and necrosis.

Apoptosis is a programmed form of cell death that occurs as a normal and necessary process in the development and maintenance of healthy tissues. During apoptosis, the cell's DNA is broken down into small fragments, the cell shrinks, and the membrane around the cell becomes fragmented, allowing the cell to be easily removed by phagocytic cells without causing an inflammatory response.

Necrosis, on the other hand, is a form of cell death that occurs as a result of acute tissue injury or overwhelming stress. During necrosis, the cell's membrane becomes damaged and the contents of the cell are released into the surrounding tissue, causing an inflammatory response.

There are also other forms of cell death, such as autophagy, which is a process by which cells break down their own organelles and proteins to recycle nutrients and maintain energy homeostasis, and pyroptosis, which is a form of programmed cell death that occurs in response to infection and involves the activation of inflammatory caspases.

Cell death is an important process in many physiological and pathological processes, including development, tissue homeostasis, and disease. Dysregulation of cell death can contribute to the development of various diseases, including cancer, neurodegenerative disorders, and autoimmune diseases.

Necrosis is the premature death of cells or tissues due to damage or injury, such as from infection, trauma, infarction (lack of blood supply), or toxic substances. It's a pathological process that results in the uncontrolled and passive degradation of cellular components, ultimately leading to the release of intracellular contents into the extracellular space. This can cause local inflammation and may lead to further tissue damage if not treated promptly.

There are different types of necrosis, including coagulative, liquefactive, caseous, fat, fibrinoid, and gangrenous necrosis, each with distinct histological features depending on the underlying cause and the affected tissues or organs.

Microbial viability is the ability of a microorganism to grow, reproduce and maintain its essential life functions. It can be determined through various methods such as cell growth in culture media, staining techniques that detect metabolic activity, or direct observation of active movement. In contrast, non-viable microorganisms are those that have been killed or inactivated and cannot replicate or cause further harm. The measurement of microbial viability is important in various fields such as medicine, food safety, water quality, and environmental monitoring to assess the effectiveness of disinfection and sterilization procedures, and to determine the presence and concentration of harmful bacteria in different environments.

Caspase-3 is a type of protease enzyme that plays a central role in the execution-phase of cell apoptosis, or programmed cell death. It's also known as CPP32 (CPP for ced-3 protease precursor) or apopain. Caspase-3 is produced as an inactive protein that is activated when cleaved by other caspases during the early stages of apoptosis. Once activated, it cleaves a variety of cellular proteins, including structural proteins, enzymes, and signal transduction proteins, leading to the characteristic morphological and biochemical changes associated with apoptotic cell death. Caspase-3 is often referred to as the "death protease" because of its crucial role in executing the cell death program.

Cell membrane permeability refers to the ability of various substances, such as molecules and ions, to pass through the cell membrane. The cell membrane, also known as the plasma membrane, is a thin, flexible barrier that surrounds all cells, controlling what enters and leaves the cell. Its primary function is to protect the cell's internal environment and maintain homeostasis.

The permeability of the cell membrane depends on its structure, which consists of a phospholipid bilayer interspersed with proteins. The hydrophilic (water-loving) heads of the phospholipids face outward, while the hydrophobic (water-fearing) tails face inward, creating a barrier that is generally impermeable to large, polar, or charged molecules.

However, specific proteins within the membrane, called channels and transporters, allow certain substances to cross the membrane. Channels are protein structures that span the membrane and provide a pore for ions or small uncharged molecules to pass through. Transporters, on the other hand, are proteins that bind to specific molecules and facilitate their movement across the membrane, often using energy in the form of ATP.

The permeability of the cell membrane can be influenced by various factors, such as temperature, pH, and the presence of certain chemicals or drugs. Changes in permeability can have significant consequences for the cell's function and survival, as they can disrupt ion balances, nutrient uptake, waste removal, and signal transduction.

Fluorescent dyes are substances that emit light upon excitation by absorbing light of a shorter wavelength. In a medical context, these dyes are often used in various diagnostic tests and procedures to highlight or mark certain structures or substances within the body. For example, fluorescent dyes may be used in imaging techniques such as fluorescence microscopy or fluorescence angiography to help visualize cells, tissues, or blood vessels. These dyes can also be used in flow cytometry to identify and sort specific types of cells. The choice of fluorescent dye depends on the specific application and the desired properties, such as excitation and emission spectra, quantum yield, and photostability.

DNA fragmentation is the breaking of DNA strands into smaller pieces. This process can occur naturally during apoptosis, or programmed cell death, where the DNA is broken down and packaged into apoptotic bodies to be safely eliminated from the body. However, excessive or abnormal DNA fragmentation can also occur due to various factors such as oxidative stress, exposure to genotoxic agents, or certain medical conditions. This can lead to genetic instability, cellular dysfunction, and increased risk of diseases such as cancer. In the context of reproductive medicine, high levels of DNA fragmentation in sperm cells have been linked to male infertility and poor assisted reproductive technology outcomes.

An azide is a chemical compound that contains the functional group -N=N+=N-, which consists of three nitrogen atoms joined by covalent bonds. In organic chemistry, azides are often used as reagents in various chemical reactions, such as the azide-alkyne cycloaddition (also known as the "click reaction").

In medical terminology, azides may refer to a class of drugs that contain an azido group and are used for their pharmacological effects. For example, sodium nitroprusside is a vasodilator drug that contains an azido group and is used to treat hypertensive emergencies.

However, it's worth noting that azides can also be toxic and potentially explosive under certain conditions, so they must be handled with care in laboratory settings.

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.

Bisbenzimidazoles are a class of chemical compounds consisting of two benzimidazole rings joined by a bridge. They are often used in biochemistry and molecular biology as fluorescent dyes for the staining and detection of DNA in various applications, such as DNA sequencing, Southern blotting, and fluorescence in situ hybridization (FISH).

One of the most commonly used bisbenzimidazoles is 4',6-diamidino-2-phenylindole (DAPI), which binds to the minor groove of DNA and emits blue fluorescence upon excitation. This property makes DAPI a useful tool for visualizing nuclei in cells and tissues, as well as for detecting and quantifying DNA in various experimental settings.

It's important to note that while bisbenzimidazoles have many uses in scientific research, they are not typically used as therapeutic agents in medicine.

"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.

Ethidium is a fluorescent, intercalating compound that is often used in molecular biology to stain DNA. When ethidium bromide, a common form of ethidium, binds to DNA, it causes the DNA to fluoresce brightly under ultraviolet light. This property makes it useful for visualizing DNA bands on gels, such as agarose or polyacrylamide gels, during techniques like gel electrophoresis.

It is important to note that ethidium bromide is a mutagen and should be handled with care. It can cause damage to DNA, which can lead to mutations, and it can also be harmful if inhaled or ingested. Therefore, appropriate safety precautions must be taken when working with this compound.

A cell line that is derived from tumor cells and has been adapted to grow in culture. These cell lines are often used in research to study the characteristics of cancer cells, including their growth patterns, genetic changes, and responses to various treatments. They can be established from many different types of tumors, such as carcinomas, sarcomas, and leukemias. Once established, these cell lines can be grown and maintained indefinitely in the laboratory, allowing researchers to conduct experiments and studies that would not be feasible using primary tumor cells. It is important to note that tumor cell lines may not always accurately represent the behavior of the original tumor, as they can undergo genetic changes during their time in culture.

Mitochondrial membrane potential is the electric potential difference (voltage) across the inner mitochondrial membrane. It is negative inside the mitochondria and positive outside. This electrical gradient is established by the active transport of hydrogen ions (protons) out of the mitochondrial matrix and into the intermembrane space by complexes in the electron transport chain during oxidative phosphorylation. The energy stored in this electrochemical gradient is used to generate ATP, which is the main source of energy for cellular metabolism.

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.

Caspases are a family of protease enzymes that play essential roles in programmed cell death, also known as apoptosis. These enzymes are produced as inactive precursors and are activated when cells receive signals to undergo apoptosis. Once activated, caspases cleave specific protein substrates, leading to the characteristic morphological changes and DNA fragmentation associated with apoptotic cell death. Caspases also play roles in other cellular processes, including inflammation and differentiation. There are two types of caspases: initiator caspases (caspase-2, -8, -9, and -10) and effector caspases (caspase-3, -6, and -7). Initiator caspases are activated in response to various apoptotic signals and then activate the effector caspases, which carry out the proteolytic cleavage of cellular proteins. Dysregulation of caspase activity has been implicated in a variety of diseases, including neurodegenerative disorders, ischemic injury, and cancer.

Fluorescence microscopy is a type of microscopy that uses fluorescent dyes or proteins to highlight and visualize specific components within a sample. In this technique, the sample is illuminated with high-energy light, typically ultraviolet (UV) or blue light, which excites the fluorescent molecules causing them to emit lower-energy, longer-wavelength light, usually visible light in the form of various colors. This emitted light is then collected by the microscope and detected to produce an image.

Fluorescence microscopy has several advantages over traditional brightfield microscopy, including the ability to visualize specific structures or molecules within a complex sample, increased sensitivity, and the potential for quantitative analysis. It is widely used in various fields of biology and medicine, such as cell biology, neuroscience, and pathology, to study the structure, function, and interactions of cells and proteins.

There are several types of fluorescence microscopy techniques, including widefield fluorescence microscopy, confocal microscopy, two-photon microscopy, and total internal reflection fluorescence (TIRF) microscopy, each with its own strengths and limitations. These techniques can provide valuable insights into the behavior of cells and proteins in health and disease.

Fluorescein is not a medical condition, but rather a diagnostic dye that is used in various medical tests and procedures. It is a fluorescent compound that absorbs light at one wavelength and emits light at another wavelength, which makes it useful for imaging and detecting various conditions.

In ophthalmology, fluorescein is commonly used in eye examinations to evaluate the health of the cornea, conjunctiva, and anterior chamber of the eye. A fluorescein dye is applied to the surface of the eye, and then the eye is examined under a blue light. The dye highlights any damage or abnormalities on the surface of the eye, such as scratches, ulcers, or inflammation.

Fluorescein is also used in angiography, a medical imaging technique used to examine blood vessels in the body. A fluorescein dye is injected into a vein, and then a special camera takes pictures of the dye as it flows through the blood vessels. This can help doctors diagnose and monitor conditions such as cancer, diabetes, and macular degeneration.

Overall, fluorescein is a valuable diagnostic tool that helps medical professionals detect and monitor various conditions in the body.

'Azure stains' is a term used in pathology to describe a histological staining technique that uses a type of dye called methyl blue, which turns the stained structures a blue-purple color. This technique is often used to stain acid mucins, which are found in various types of tissues and can be indicative of certain medical conditions.

In particular, azure stains are sometimes used to help diagnose certain types of cancer, such as mucoepidermoid carcinoma, a type of salivary gland tumor that produces acid mucins. The staining technique can help pathologists identify the presence and distribution of these mucins within the tumor cells, which can aid in making an accurate diagnosis and determining the best course of treatment.

It's worth noting that there are several different types of histological stains that use various dyes to highlight different structures or features within tissues. Azure stains are just one example of these techniques, and they are typically used in conjunction with other staining methods to provide a comprehensive picture of the tissue being examined.

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.

"Nitrosomonas europaea" is not a medical term, but rather a specific type of bacteria known as a nitrifying bacterium. It is commonly found in soil, freshwater, and wastewater environments. This bacterium plays a crucial role in the nitrogen cycle by converting ammonia into nitrites through a process called nitrification.

While not directly related to human health, Nitrosomonas europaea can have indirect effects on public health. For example, when present in wastewater treatment systems, it helps convert harmful ammonia into less toxic nitrite, which is then further converted into nitrate by other bacteria. This process helps protect aquatic environments from the negative impacts of excess nutrient pollution.

However, when nitrate accumulates in drinking water, it can pose health risks, particularly for infants under six months old, who may develop a condition called blue baby syndrome (methemoglobinemia) if exposed to high levels of nitrate. Therefore, monitoring and controlling nitrifying bacteria in wastewater treatment systems is essential to protect both the environment and public health.

Fluorescein-5-isothiocyanate (FITC) is not a medical term per se, but a chemical compound commonly used in biomedical research and clinical diagnostics. Therefore, I will provide a general definition of this term:

Fluorescein-5-isothiocyanate (FITC) is a fluorescent dye with an absorption maximum at approximately 492-495 nm and an emission maximum at around 518-525 nm. It is widely used as a labeling reagent for various biological molecules, such as antibodies, proteins, and nucleic acids, to study their structure, function, and interactions in techniques like flow cytometry, immunofluorescence microscopy, and western blotting. The isothiocyanate group (-N=C=S) in the FITC molecule reacts with primary amines (-NH2) present in biological molecules to form a stable thiourea bond, enabling specific labeling of target molecules for detection and analysis.

Quinolinium compounds are a class of organic compounds that contain a quaternary ammonium cation with a quinolinium core. Quinoline is a heterocyclic aromatic organic compound similar to benzene and pyridine, containing two nitrogen atoms at positions 1 and 2 of the six-member ring. When one of the hydrogen atoms in the quinoline is replaced by a positively charged group (such as a methyl or ethyl group), it forms a quaternary ammonium salt, known as a quinolinium compound.

Quinolinium compounds are often used as antimicrobial agents, particularly against gram-positive bacteria and some fungi. They can also be used as building blocks in organic synthesis, catalysts, and dyes. Some examples of quinolinium compounds include quinoline yellow, a food coloring agent, and chloroquine and hydroxychloroquine, drugs used to treat malaria and certain autoimmune diseases.

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.

Acetylcholinesterase (AChE) is an enzyme that catalyzes the hydrolysis of acetylcholine (ACh), a neurotransmitter, into choline and acetic acid. This enzyme plays a crucial role in regulating the transmission of nerve impulses across the synapse, the junction between two neurons or between a neuron and a muscle fiber.

Acetylcholinesterase is located in the synaptic cleft, the narrow gap between the presynaptic and postsynaptic membranes. When ACh is released from the presynaptic membrane and binds to receptors on the postsynaptic membrane, it triggers a response in the target cell. Acetylcholinesterase rapidly breaks down ACh, terminating its action and allowing for rapid cycling of neurotransmission.

Inhibition of acetylcholinesterase leads to an accumulation of ACh in the synaptic cleft, prolonging its effects on the postsynaptic membrane. This can result in excessive stimulation of cholinergic receptors and overactivation of the cholinergic system, which may cause a range of symptoms, including muscle weakness, fasciculations, sweating, salivation, lacrimation, urination, defecation, bradycardia, and bronchoconstriction.

Acetylcholinesterase inhibitors are used in the treatment of various medical conditions, such as Alzheimer's disease, myasthenia gravis, and glaucoma. However, they can also be used as chemical weapons, such as nerve agents, due to their ability to disrupt the nervous system and cause severe toxicity.

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.

L-Lactate Dehydrogenase (LDH) is an enzyme found in various tissues within the body, including the heart, liver, kidneys, muscles, and brain. It plays a crucial role in the process of energy production, particularly during anaerobic conditions when oxygen levels are low.

In the presence of the coenzyme NADH, LDH catalyzes the conversion of pyruvate to lactate, generating NAD+ as a byproduct. Conversely, in the presence of NAD+, LDH can convert lactate back to pyruvate using NADH. This reversible reaction is essential for maintaining the balance between lactate and pyruvate levels within cells.

Elevated blood levels of LDH may indicate tissue damage or injury, as this enzyme can be released into the circulation following cellular breakdown. As a result, LDH is often used as a nonspecific biomarker for various medical conditions, such as myocardial infarction (heart attack), liver disease, muscle damage, and certain types of cancer. However, it's important to note that an isolated increase in LDH does not necessarily pinpoint the exact location or cause of tissue damage, and further diagnostic tests are usually required for confirmation.

Indicators and reagents are terms commonly used in the field of clinical chemistry and laboratory medicine. Here are their definitions:

1. Indicator: An indicator is a substance that changes its color or other physical properties in response to a chemical change, such as a change in pH, oxidation-reduction potential, or the presence of a particular ion or molecule. Indicators are often used in laboratory tests to monitor or signal the progress of a reaction or to indicate the end point of a titration. A familiar example is the use of phenolphthalein as a pH indicator in acid-base titrations, which turns pink in basic solutions and colorless in acidic solutions.

2. Reagent: A reagent is a substance that is added to a system (such as a sample or a reaction mixture) to bring about a chemical reaction, test for the presence or absence of a particular component, or measure the concentration of a specific analyte. Reagents are typically chemicals with well-defined and consistent properties, allowing them to be used reliably in analytical procedures. Examples of reagents include enzymes, antibodies, dyes, metal ions, and organic compounds. In laboratory settings, reagents are often prepared and standardized according to strict protocols to ensure their quality and performance in diagnostic tests and research applications.

Proto-oncogene proteins c-bcl-2 are a group of proteins that play a role in regulating cell death (apoptosis). The c-bcl-2 gene produces one of these proteins, which helps to prevent cells from undergoing apoptosis. This protein is located on the membrane of mitochondria and endoplasmic reticulum and it can inhibit the release of cytochrome c, a key player in the activation of caspases, which are enzymes that trigger apoptosis.

In normal cells, the regulation of c-bcl-2 protein helps to maintain a balance between cell proliferation and cell death, ensuring proper tissue homeostasis. However, when the c-bcl-2 gene is mutated or its expression is dysregulated, it can contribute to cancer development by allowing cancer cells to survive and proliferate. High levels of c-bcl-2 protein have been found in many types of cancer, including leukemia, lymphoma, and carcinomas, and are often associated with a poor prognosis.

Semen preservation is the process of collecting, liquefying, testing, and storing semen samples for future use in assisted reproductive technologies (ART) such as artificial insemination (AI), in vitro fertilization (IVF), or intracytoplasmic sperm injection (ICSI). The semen sample is usually collected through masturbation, and then it is mixed with a cryoprotectant solution to prevent damage during the freezing and thawing process. After that, the sample is divided into straws or vials and frozen in liquid nitrogen tanks at temperatures below -196°C. Properly preserved semen can be stored for many years without significant loss of quality or fertility potential. Semen preservation is often recommended for men who are about to undergo medical treatments that may affect their sperm production or fertility, such as chemotherapy or radiation therapy, or for those who wish to postpone fatherhood for personal or medical reasons.

Phosphatidylserines are a type of phospholipids that are essential components of the cell membrane, particularly in the brain. They play a crucial role in maintaining the fluidity and permeability of the cell membrane, and are involved in various cellular processes such as signal transduction, protein anchorage, and apoptosis (programmed cell death). Phosphatidylserines contain a polar head group made up of serine amino acids and two non-polar fatty acid tails. They are abundant in the inner layer of the cell membrane but can be externalized to the outer layer during apoptosis, where they serve as signals for recognition and removal of dying cells by the immune system. Phosphatidylserines have been studied for their potential benefits in various medical conditions, including cognitive decline, Alzheimer's disease, and depression.

Butyrylthiocholine is a synthetic chemical compound that is often used in scientific research, particularly in the study of enzymes and neurotransmitters. It is the substrate for the enzyme butyrylcholinesterase, which is found in the blood and helps to break down certain types of drugs and neurotransmitters.

In biochemical terms, butyrylthiocholine is a choline ester of butyric acid, with a thio (sulfur) group replacing one of the oxygen atoms in the ester linkage. This structural feature makes it an excellent substrate for butyrylcholinesterase, as the sulfur atom can form a covalent bond with the enzyme's active site, leading to rapid and specific catalysis.

It is important to note that butyrylthiocholine itself does not have any direct medical relevance, but rather serves as a tool for studying the mechanisms of enzymes and other biological processes.

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.

Edrophonium is a type of medication called an anticholinesterase agent. It works by blocking the breakdown of acetylcholine, a neurotransmitter in the body that is important for muscle contraction. This results in an increase in the amount of acetylcholine available to stimulate muscle contraction.

Edrophonium is used as a diagnostic aid in the diagnosis of myasthenia gravis, a neuromuscular disorder characterized by muscle weakness and fatigue. It is also used to reverse the effects of non-depolarizing muscle relaxants, which are medications that are sometimes given during surgery to temporarily paralyze muscles.

Edrophonium is administered intravenously (through a vein) and its effects usually begin within 30 seconds to 1 minute after injection and last for about 5 to 10 minutes. Common side effects of edrophonium include sweating, increased salivation, and muscle twitching. More serious side effects, such as seizures or cardiac arrest, can occur but are rare.

It is important to note that edrophonium should only be used under the supervision of a healthcare professional, as it can cause serious side effects if not used properly.

Confocal microscopy is a powerful imaging technique used in medical and biological research to obtain high-resolution, contrast-rich images of thick samples. This super-resolution technology provides detailed visualization of cellular structures and processes at various depths within a specimen.

In confocal microscopy, a laser beam focused through a pinhole illuminates a small spot within the sample. The emitted fluorescence or reflected light from this spot is then collected by a detector, passing through a second pinhole that ensures only light from the focal plane reaches the detector. This process eliminates out-of-focus light, resulting in sharp images with improved contrast compared to conventional widefield microscopy.

By scanning the laser beam across the sample in a raster pattern and collecting fluorescence at each point, confocal microscopy generates optical sections of the specimen. These sections can be combined to create three-dimensional reconstructions, allowing researchers to study cellular architecture and interactions within complex tissues.

Confocal microscopy has numerous applications in medical research, including studying protein localization, tracking intracellular dynamics, analyzing cell morphology, and investigating disease mechanisms at the cellular level. Additionally, it is widely used in clinical settings for diagnostic purposes, such as analyzing skin lesions or detecting pathogens in patient samples.

Mitochondria are specialized structures located inside cells that convert the energy from food into ATP (adenosine triphosphate), which is the primary form of energy used by cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of chemical energy. Mitochondria are also involved in various other cellular processes, such as signaling, differentiation, and apoptosis (programmed cell death).

Mitochondria have their own DNA, known as mitochondrial DNA (mtDNA), which is inherited maternally. This means that mtDNA is passed down from the mother to her offspring through the egg cells. Mitochondrial dysfunction has been linked to a variety of diseases and conditions, including neurodegenerative disorders, diabetes, and aging.

Laser scanning cytometry (LSC) is a technology that combines flow cytometry and microscope-based imaging to enable the quantitative analysis of cellular components or molecules at a single-cell level. In LSC, a laser beam is used to scan and excite fluorescently labeled cells or tissue sections on a glass slide, and the emitted light is collected and analyzed to determine the amount and distribution of specific markers within each cell. This technique allows for high-resolution spatial analysis of cells, making it useful in various research fields such as cell biology, cancer research, and drug development.

Spermatozoa are the male reproductive cells, or gametes, that are produced in the testes. They are microscopic, flagellated (tail-equipped) cells that are highly specialized for fertilization. A spermatozoon consists of a head, neck, and tail. The head contains the genetic material within the nucleus, covered by a cap-like structure called the acrosome which contains enzymes to help the sperm penetrate the female's egg (ovum). The long, thin tail propels the sperm forward through fluid, such as semen, enabling its journey towards the egg for fertilization.

Phenanthridines are a class of heterocyclic aromatic organic compounds that consist of a phenanthrene core (a polycyclic aromatic hydrocarbon made up of three benzene rings) fused with a pyridine ring (a six-membered ring containing five carbon atoms and one nitrogen atom). They have the chemical formula C12H9N.

Phenanthridines are important in medicinal chemistry because some of their derivatives exhibit various biological activities, such as antitumor, antibacterial, antifungal, anti-inflammatory, and antiviral properties. Some well-known phenanthridine derivatives include the chemotherapeutic agents amsacrine and doxorubicin, which are used to treat various types of cancer.

It's worth noting that while phenanthridines have important medical applications, they can also be toxic or harmful if not handled properly. Therefore, it's essential to follow proper safety protocols when working with these compounds in a laboratory setting.

Disinfection is the process of eliminating or reducing harmful microorganisms from inanimate objects and surfaces through the use of chemicals, heat, or other methods. The goal of disinfection is to reduce the number of pathogens to a level that is considered safe for human health. Disinfection is an important step in preventing the spread of infectious diseases in healthcare settings, food processing facilities, and other environments where there is a risk of infection transmission.

It's important to note that disinfection is not the same as sterilization, which is the complete elimination of all microorganisms, including spores. Disinfection is generally less effective than sterilization but is often sufficient for most non-critical surfaces and objects. The choice between disinfection and sterilization depends on the level of risk associated with the item or surface being treated and the intended use of that item or surface.

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.

'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.

Ploidy is a term used in genetics to describe the number of sets of chromosomes in a cell or an organism. The ploidy level can have important implications for genetic inheritance and expression, as well as for evolutionary processes such as speciation and hybridization.

In most animals, including humans, the normal ploidy level is diploid, meaning that each cell contains two sets of chromosomes - one set inherited from each parent. However, there are also many examples of polyploidy, in which an organism has more than two sets of chromosomes.

Polyploidy can arise through various mechanisms, such as genome duplication or hybridization between different species. In some cases, polyploidy may confer evolutionary advantages, such as increased genetic diversity and adaptability to new environments. However, it can also lead to reproductive isolation and the formation of new species.

In plants, polyploidy is relatively common and has played a significant role in their evolution and diversification. Many crop plants are polyploids, including wheat, cotton, and tobacco. In some cases, artificial induction of polyploidy has been used to create new varieties with desirable traits for agriculture and horticulture.

Overall, ploidy is an important concept in genetics and evolution, with implications for a wide range of biological processes and phenomena.

A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.

Electroporation is a medical procedure that involves the use of electrical fields to create temporary pores or openings in the cell membrane, allowing for the efficient uptake of molecules, drugs, or genetic material into the cell. This technique can be used for various purposes, including delivering genes in gene therapy, introducing drugs for cancer treatment, or transforming cells in laboratory research. The electrical pulses are carefully controlled to ensure that they are strong enough to create pores in the membrane without causing permanent damage to the cell. After the electrical field is removed, the pores typically close and the cell membrane returns to its normal state.

Euphorbia is a genus of plants that belongs to the spurge family (Euphorbiaceae). It contains around 2,000 species of shrubs, trees, and herbs that are found worldwide, particularly in tropical and subtropical regions. Many euphorbias are known for their milky sap, which can be toxic or irritating to the skin and mucous membranes. Some species of euphorbia are cultivated as ornamental plants due to their attractive flowers and foliage, while others have medicinal or industrial uses. However, it's important to note that some euphorbias can be invasive and harmful to local ecosystems, so care should be taken when handling or growing them.

Tetrazolium salts are a group of compounds that are commonly used as indicators of cell viability and metabolic activity. These salts are reduced by the action of dehydrogenase enzymes in living cells, resulting in the formation of formazan dyes, which are colored and can be measured spectrophotometrically.

The most commonly used tetrazolium salt is 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), which is reduced to a purple formazan product by mitochondrial dehydrogenases in viable cells. Other tetrazolium salts include 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), which is reduced to a water-soluble formazan product, and 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS), which is reduced to a water-soluble formazan product by NAD(P)H-dependent dehydrogenases.

Tetrazolium salts are widely used in cell culture studies, toxicity testing, and drug development to assess cell viability, proliferation, and cytotoxicity. However, it is important to note that tetrazolium salt reduction can also occur in some non-viable cells or under certain experimental conditions, which may lead to false positive results. Therefore, these assays should be used with caution and validated for specific applications.

I believe there may be some confusion in your question. "Organic chemicals" is a broad term that refers to chemical compounds containing carbon, often bonded to hydrogen. These can include natural substances like sugars and proteins, as well as synthetic materials like plastics and pharmaceuticals.

However, if you're asking about "organic" in the context of farming or food production, it refers to things that are produced without the use of synthetic pesticides, fertilizers, genetically modified organisms, irradiation, and sewage sludge.

In the field of medicine, there isn't a specific definition for 'organic chemicals'. If certain organic chemicals are used in medical contexts, they would be defined by their specific use or function (like a specific drug name).

Enzyme inhibitors are substances that bind to an enzyme and decrease its activity, preventing it from catalyzing a chemical reaction in the body. They can work by several mechanisms, including blocking the active site where the substrate binds, or binding to another site on the enzyme to change its shape and prevent substrate binding. Enzyme inhibitors are often used as drugs to treat various medical conditions, such as high blood pressure, abnormal heart rhythms, and bacterial infections. They can also be found naturally in some foods and plants, and can be used in research to understand enzyme function and regulation.

Reactive Oxygen Species (ROS) are highly reactive molecules containing oxygen, including peroxides, superoxide, hydroxyl radical, and singlet oxygen. They are naturally produced as byproducts of normal cellular metabolism in the mitochondria, and can also be generated by external sources such as ionizing radiation, tobacco smoke, and air pollutants. At low or moderate concentrations, ROS play important roles in cell signaling and homeostasis, but at high concentrations, they can cause significant damage to cell structures, including lipids, proteins, and DNA, leading to oxidative stress and potential cell death.

BCL-2-associated X protein, often abbreviated as BAX, is a type of protein belonging to the BCL-2 family. The BCL-2 family of proteins plays a crucial role in regulating programmed cell death, also known as apoptosis. Specifically, BAX is a pro-apoptotic protein, which means that it promotes cell death.

BAX is encoded by the BAX gene, and it functions by forming pores in the outer membrane of the mitochondria, leading to the release of cytochrome c and other pro-apoptotic factors into the cytosol. This triggers a cascade of events that ultimately leads to cell death.

Dysregulation of BAX and other BCL-2 family proteins has been implicated in various diseases, including cancer and neurodegenerative disorders. For example, reduced levels of BAX have been observed in some types of cancer, which may contribute to tumor growth and resistance to chemotherapy. On the other hand, excessive activation of BAX has been linked to neuronal death in conditions such as Alzheimer's disease and Parkinson's disease.

Rhodamine 123 is not a medical term, but a chemical compound. It's a fluorescent dye used in various scientific and research applications, particularly in the field of cell biology. Rhodamine 123 has an affinity for mitochondria, the energy-producing structures in cells, making it useful as a marker to study mitochondrial function and distribution within cells.

In summary, Rhodamine 123 is not a medical definition itself, but it can be used in medical research contexts to investigate cellular processes.

... (PMA) is a photoreactive DNA-binding dye that preferentially binds to dsDNA. It is used to detect viable ... "PMA dye , Propidium Monoazide , Biotium, Inc". Retrieved 8 March 2016. Nocker, Andreas; Cheung, Ching-Ying; Camper, Anne K. ( ... Nocker, Andreas; Ching-Ying Cheung, and Anne K. Camper (2006). "Comparison of propidium monoazide with ethidium monoazide for ... Nocker, Andreas; Cheung, Ching-Ying; Camper, Anne K. (November 2006). "Comparison of propidium monoazide with ethidium ...
... (or PI) is a fluorescent intercalating agent that can be used to stain cells and nucleic acids. PI binds to ... Propidium Iodide is not membrane-permeable, making it useful to differentiate necrotic, apoptotic and healthy cells based on ... "Propidium Iodide". ThermoFisher. Suzuki T, Fujikura K, Higashiyama T, Takata K (1 January 1997). "DNA staining for fluorescence ... "Propidium Iodide Solution - BioLegend". Archived from the original on 10 February 2015. Retrieved 10 January 2015. Lecoeur H ( ...
The first protocol for cell cycle analysis using propidium iodide staining was presented in 1975 by Awtar Krishan from Harvard ... Riccardi C, Nicoletti I (9 November 2006). "Analysis of apoptosis by propidium iodide staining and flow cytometry". Nature ... Krishan A. (July 1975). "Rapid flow cytofluorometric analysis of mammalian cell cycle by propidium iodide staining". The ... Aside from propidium iodide and acridine orange, quantifiable dyes that are frequently used include (but are not limited to) ...
Examples of such dyes are ethidium bromide and propidium iodide. It is an isomer of acridine. Phenanthridine was discovered by ...
Riccardi C, Nicoletti I (9 November 2006). "Analysis of apoptosis by propidium iodide staining and flow cytometry". Nature ... "A rapid and simple method for measuring thymocyte apoptosis by propidium iodide staining and flow cytometry". Journal of ...
Nocker, Andreas; Sossa-Fernandez, Priscilla; Burr, Mark D.; Camper, Anne K. (2007-08-01). "Use of propidium monoazide for live/ ... Nocker, Andreas; Cheung, Ching-Ying; Camper, Anne K. (2006-11-01). "Comparison of propidium monoazide with ethidium monoazide ... Schnetzinger, Franz; Pan, Youwen; Nocker, Andreas (2013-03-01). "Use of propidium monoazide and increased amplicon length ... which demonstrated in successive works the potential of this technology and also suggested Propidium monoazide as a better ...
"Injection of Propidium Iodide into HeLa Cells Using a Silicon Nanoinjection Lance Array". Journal of Nanotechnology in ...
Only vital, propidium excluding EpCAM positive cells are counted as potential tumor cells. Only living cells can grow into ... Together with the nuclear staining with propidium iodide the maintrac method can distinguish between dead and living cells. ...
Propidium iodide is a fluorescent intercalating agent that can be used to stain cells. Propidium iodide is used as a DNA stain ... Propidium Iodide cannot cross the membrane of live cells, making it useful to differentiate necrotic, apoptotic and healthy ... trypan blue or propidium iodide for eukaryotic cells). Those that enter and stain living cells are called supravital stains (e. ...
... and Propidium Iodide". Arbuscular Mycorrhizal Fungi. 2146: 53-59. doi:10.1007/978-1-0716-0603-2_5. hdl:2318/1740844. v t e ( ...
Eosin dye exclusion Propidium iodide, DNA stain that can differentiate necrotic, apoptotic and normal cells. Trypan Blue, a ...
It is also used in combination with propidium iodide (PI) to determine viability in eukaryotic cells. Living cells will ...
Propidium iodide staining revealed that only the basal surface of the hook is of nuclear origin. These apical hooks are ...
For example, in dead cells, propidium iodide (PI) can penetrate the nucleus where it binds to DNA. The fluorescent signal of PI ...
During this stage the membrane becomes abnormally permeable to trypan blue and propidium iodide, indicating membrane compromise ...
It is also thought that Zeta toxin induces reversible protective dormancy and permeation to propidium iodide (PI). This protein ...
Vital dyes, such as trypan blue or propidium iodide are normally excluded from the inside of healthy cells; however, if the ...
For instance propidium iodide binds to DNA of dead cells and fluorescent signal is measured by flow cytometry. CDC assays are ...
Several dyes have been studied for MUSE's application, including eosin, rhodamine, DAPI, Hoechst, acridine orange, propidium ...
An analysis of fish genomes resulted in significantly different genome sizes when propidium iodide (PI) and DAPI were used, ...
coincident detection of zinc accumulation and propidium iodide (a traditional cell death indicator) uptake in multiple cell ... and it was also demonstrated that colocalized detection of zinc increase and the well accepted cell death indicator propidium ...
The application of propidium iodide staining to the study of the macronucleus and micronuclei in the suctorian Heliophyra sp. ...
... can be used in conjunction with ethidium bromide or propidium iodide to differentiate between viable, apoptotic ...
Since the cell viability is determined by electric current exclusion, viability dyes such as Trypan blue and Propidium iodide ...
The result is about 30% smaller than the genome size estimated by flow cytometry of isolated nuclei stained with propidium ...
... or propidium iodide. Analysis of FISH specimens is done by fluorescence microscopy by a clinical laboratory specialist in ...
Staining with DNA dyes propidium iodide or 4',6'-diamidino-2-phenylindole (DAPI) allows delineation or sorting of cells between ...
Examples of this type of assay include propidium iodide, trypan blue, and 7-Aminoactinomycin D. Mitochondrial activity or ... Propidium iodide, DNA stain that can differentiate necrotic, apoptotic and normal cells. Resazurin TUNEL assay Cytotoxicity ... Calcein AM Clonogenic assay Ethidium homodimer assay Evans blue Fluorescein diacetate hydrolysis/Propidium iodide staining (FDA ...
... propidium MeSH D03.494.704.353 - clofazimine MeSH D03.494.704.550 - methylphenazonium methosulfate MeSH D03.494.704.600 - ...
Propidium iodide, a chemical used as a DNA stain Primary immunodeficiency Protease inhibitor (pharmacology), class of drugs ...

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