Substances that influence the course of a chemical reaction by ready combination with free radicals. Among other effects, this combining activity protects pancreatic islets against damage by cytokines and prevents myocardial and pulmonary perfusion injuries.
Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.
An analgesic and antipyretic that has been given by mouth and as ear drops. Antipyrine is often used in testing the effects of other drugs or diseases on drug-metabolizing enzymes in the liver. (From Martindale, The Extra Pharmacopoeia, 30th ed, p29)
The univalent radical OH. Hydroxyl radical is a potent oxidizing agent.
Heterocyclic compounds in which an oxygen is attached to a cyclic nitrogen.
Naturally occurring or synthetic substances that inhibit or retard the oxidation of a substance to which it is added. They counteract the harmful and damaging effects of oxidation in animal tissues.
Sulfhydryl acylated derivative of GLYCINE.
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 large group of structurally diverse cell surface receptors that mediate endocytic uptake of modified LIPOPROTEINS. Scavenger receptors are expressed by MYELOID CELLS and some ENDOTHELIAL CELLS, and were originally characterized based on their ability to bind acetylated LOW-DENSITY LIPOPROTEINS. They can also bind a variety of other polyanionic ligand. Certain scavenger receptors can internalize micro-organisms as well as apoptotic cells.
An oxidoreductase that catalyzes the reaction between superoxide anions and hydrogen to yield molecular oxygen and hydrogen peroxide. The enzyme protects the cell against dangerous levels of superoxide. EC 1.15.1.1.
A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).
Peroxidase catalyzed oxidation of lipids using hydrogen peroxide as an electron acceptor.
Picrates are salts of picric acid, an explosive organic compound previously used as a yellow dye and antiseptic, which are now primarily used in chemical research and industrial applications. Please note that picrates should be handled with care due to their potential explosiveness when heated or subjected to friction.
A family of scavenger receptors that mediate the influx of LIPIDS into MACROPHAGES and are involved in FOAM CELL formation.
A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.
Inorganic compounds that contain the OH- group.
An oxidoreductase that catalyzes the conversion of HYDROGEN PEROXIDE to water and oxygen. It is present in many animal cells. A deficiency of this enzyme results in ACATALASIA.
The N-acetyl derivative of CYSTEINE. It is used as a mucolytic agent to reduce the viscosity of mucous secretions. It has also been shown to have antiviral effects in patients with HIV due to inhibition of viral stimulation by reactive oxygen intermediates.
A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.
A photographic fixative used also in the manufacture of resins. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), this substance may reasonably be anticipated to be a carcinogen (Merck Index, 9th ed). Many of its derivatives are ANTITHYROID AGENTS and/or FREE RADICAL SCAVENGERS.
A family of scavenger receptors that are predominately localized to CAVEOLAE of the PLASMA MEMBRANE and bind HIGH DENSITY LIPOPROTEINS.
Inorganic oxides that contain nitrogen.
The dialdehyde of malonic acid.
Highly reactive compounds produced when oxygen is reduced by a single electron. In biological systems, they may be generated during the normal catalytic function of a number of enzymes and during the oxidation of hemoglobin to METHEMOGLOBIN. In living organisms, SUPEROXIDE DISMUTASE protects the cell from the deleterious effects of superoxides.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
An NAD-dependent enzyme that catalyzes the oxidation of nitrite to nitrate. It is a FLAVOPROTEIN that contains IRON and MOLYBDENUM and is involved in the first step of nitrate assimilation in PLANTS; FUNGI; and BACTERIA. It was formerly classified as EC 1.6.6.1.
Molecules which contain an atom or a group of atoms exhibiting an unpaired electron spin that can be detected by electron spin resonance spectroscopy and can be bonded to another molecule. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)
Compounds based on reduced IMIDAZOLES containing a single double bond.
Natural product isolated from Streptomyces pilosus. It forms iron complexes and is used as a chelating agent, particularly in the mesylate form.
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
An iron-molybdenum flavoprotein containing FLAVIN-ADENINE DINUCLEOTIDE that oxidizes hypoxanthine, some other purines and pterins, and aldehydes. Deficiency of the enzyme, an autosomal recessive trait, causes xanthinuria.
A biogenic amine that is found in animals and plants. In mammals, melatonin is produced by the PINEAL GLAND. Its secretion increases in darkness and decreases during exposure to light. Melatonin is implicated in the regulation of SLEEP, mood, and REPRODUCTION. Melatonin is also an effective antioxidant.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
Propiophenones are a group of synthetic compounds characterized by a phenone functional group attached to a propyl chain, which have been used in various applications including as intermediates in chemical synthesis and as pharmaceutical ingredients with sedative and hypnotic properties.
Peroxides produced in the presence of a free radical by the oxidation of unsaturated fatty acids in the cell in the presence of molecular oxygen. The formation of lipid peroxides results in the destruction of the original lipid leading to the loss of integrity of the membranes. They therefore cause a variety of toxic effects in vivo and their formation is considered a pathological process in biological systems. Their formation can be inhibited by antioxidants, such as vitamin E, structural separation or low oxygen tension.
A generic descriptor for all TOCOPHEROLS and TOCOTRIENOLS that exhibit ALPHA-TOCOPHEROL activity. By virtue of the phenolic hydrogen on the 2H-1-benzopyran-6-ol nucleus, these compounds exhibit varying degree of antioxidant activity, depending on the site and number of methyl groups and the type of ISOPRENOIDS.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Biphenyl compounds are organic substances consisting of two phenyl rings connected by a single covalent bond, and can exhibit various properties and uses, including as intermediates in chemical synthesis, components in plastics and dyes, and as additives in fuels.
A XANTHINE OXIDASE inhibitor that decreases URIC ACID production. It also acts as an antimetabolite on some simpler organisms.
A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.
Adverse functional, metabolic, or structural changes in ischemic tissues resulting from the restoration of blood flow to the tissue (REPERFUSION), including swelling; HEMORRHAGE; NECROSIS; and damage from FREE RADICALS. The most common instance is MYOCARDIAL REPERFUSION INJURY.
Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.
Electron-accepting molecules in chemical reactions in which electrons are transferred from one molecule to another (OXIDATION-REDUCTION).
Inorganic or organic oxy acids of sulfur which contain the RSO2(OH) radical.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Drugs intended to prevent damage to the brain or spinal cord from ischemia, stroke, convulsions, or trauma. Some must be administered before the event, but others may be effective for some time after. They act by a variety of mechanisms, but often directly or indirectly minimize the damage produced by endogenous excitatory amino acids.
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.
A melatonin receptor subtype that is primarily found in the HYPOTHALAMUS and in the KIDNEY.
A fungistatic compound that is widely used as a food preservative. It is conjugated to GLYCINE in the liver and excreted as hippuric acid.
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 free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.
A melatonin receptor subtype primarily found expressed in the BRAIN and RETINA.
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 heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.
An enzyme catalyzing the oxidation of 2 moles of glutathione in the presence of hydrogen peroxide to yield oxidized glutathione and water. EC 1.11.1.9.
A highly polar organic liquid, that is used widely as a chemical solvent. Because of its ability to penetrate biological membranes, it is used as a vehicle for topical application of pharmaceuticals. It is also used to protect tissue during CRYOPRESERVATION. Dimethyl sulfoxide shows a range of pharmacological activity including analgesia and anti-inflammation.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
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.
A technique for detecting short-lived reactive FREE RADICALS in biological systems by providing a nitrone or nitrose compound for an addition reaction to occur which produces an ELECTRON SPIN RESONANCE SPECTROSCOPY-detectable aminoxyl radical. In spin trapping, the compound trapping the radical is called the spin trap and the addition product of the radical is identified as the spin adduct. (Free Rad Res Comm 1990;9(3-6):163)
Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
A diuretic and renal diagnostic aid related to sorbitol. It has little significant energy value as it is largely eliminated from the body before any metabolism can take place. It can be used to treat oliguria associated with kidney failure or other manifestations of inadequate renal function and has been used for determination of glomerular filtration rate. Mannitol is also commonly used as a research tool in cell biological studies, usually to control osmolarity.
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)
Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.
Cell surface proteins that bind lipoproteins with high affinity. Lipoprotein receptors in the liver and peripheral tissues mediate the regulation of plasma and cellular cholesterol metabolism and concentration. The receptors generally recognize the apolipoproteins of the lipoprotein complex, and binding is often a trigger for endocytosis.
Organic compounds containing both the hydroxyl and carboxyl radicals.
10-carbon saturated monocarboxylic acids.
Elements of limited time intervals, contributing to particular results or situations.
Damage to the MYOCARDIUM resulting from MYOCARDIAL REPERFUSION (restoration of blood flow to ischemic areas of the HEART.) Reperfusion takes place when there is spontaneous thrombolysis, THROMBOLYTIC THERAPY, collateral flow from other coronary vascular beds, or reversal of vasospasm.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.
A group of compounds that contain a bivalent O-O group, i.e., the oxygen atoms are univalent. They can either be inorganic or organic in nature. Such compounds release atomic (nascent) oxygen readily. Thus they are strong oxidizing agents and fire hazards when in contact with combustible materials, especially under high-temperature conditions. The chief industrial uses of peroxides are as oxidizing agents, bleaching agents, and initiators of polymerization. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Deoxyribose is a 5-carbon sugar (monosaccharide) that lacks one hydroxyl group at the 2' carbon position, compared to ribose, and is a key component of DNA molecules, forming part of the nucleotides along with phosphate and nitrogenous bases.
A flavoprotein enzyme that catalyzes the univalent reduction of OXYGEN using NADPH as an electron donor to create SUPEROXIDE ANION. The enzyme is dependent on a variety of CYTOCHROMES. Defects in the production of superoxide ions by enzymes such as NADPH oxidase result in GRANULOMATOUS DISEASE, CHRONIC.
The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.
A group of structurally related scavenger receptors expressed predominately by ENDOTHELIAL CELLS. They-contain repeats of EPIDERMAL GROWTH FACTOR-like cysteine-rich motifs in their extracellular domains.
Anserine is a muscle fiber protein, specifically a myosin heavy chain isoform, which is predominantly found in slow-twitch, type I muscle fibers and contributes to their contractile properties, playing a role in force production and fatigue resistance.
Leukocyte differentiation antigens and major platelet membrane glycoproteins present on MONOCYTES; ENDOTHELIAL CELLS; PLATELETS; and mammary EPITHELIAL CELLS. They play major roles in CELL ADHESION; SIGNAL TRANSDUCTION; and regulation of angiogenesis. CD36 is a receptor for THROMBOSPONDINS and can act as a scavenger receptor that recognizes and transports oxidized LIPOPROTEINS and FATTY ACIDS.
Low-molecular-weight end products, probably malondialdehyde, that are formed during the decomposition of lipid peroxidation products. These compounds react with thiobarbituric acid to form a fluorescent red adduct.
A group of phenyl benzopyrans named for having structures like FLAVONES.
A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.
A naturally occurring dipeptide neuropeptide found in muscles.
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.
Increased intracellular or extracellular fluid in brain tissue. Cytotoxic brain edema (swelling due to increased intracellular fluid) is indicative of a disturbance in cell metabolism, and is commonly associated with hypoxic or ischemic injuries (see HYPOXIA, BRAIN). An increase in extracellular fluid may be caused by increased brain capillary permeability (vasogenic edema), an osmotic gradient, local blockages in interstitial fluid pathways, or by obstruction of CSF flow (e.g., obstructive HYDROCEPHALUS). (From Childs Nerv Syst 1992 Sep; 8(6):301-6)
An NADPH-dependent enzyme that catalyzes the conversion of L-ARGININE and OXYGEN to produce CITRULLINE and NITRIC OXIDE.
The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.
Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.
A purine base found in most body tissues and fluids, certain plants, and some urinary calculi. It is an intermediate in the degradation of adenosine monophosphate to uric acid, being formed by oxidation of hypoxanthine. The methylated xanthine compounds caffeine, theobromine, and theophylline and their derivatives are used in medicine for their bronchodilator effects. (Dorland, 28th ed)
Established cell cultures that have the potential to propagate indefinitely.
A condition of decreased oxygen content at the cellular level.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
The rate dynamics in chemical or physical systems.
Organic chemicals that form two or more coordination links with an iron ion. Once coordination has occurred, the complex formed is called a chelate. The iron-binding porphyrin group of hemoglobin is an example of a metal chelate found in biological systems.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.
An oxyacid of chlorine (HClO) containing monovalent chlorine that acts as an oxidizing or reducing agent.
Chemicals that bind to and remove ions from solutions. Many chelating agents function through the formation of COORDINATION COMPLEXES with METALS.
Urea compounds which are substituted with one or more methyl groups.
The action of a drug in promoting or enhancing the effectiveness of another drug.
Cell surface molecules on cells of the immune system that specifically bind surface molecules or messenger molecules and trigger changes in the behavior of cells. Although these receptors were first identified in the immune system, many have important functions elsewhere.
Inorganic or organic compounds that contain divalent iron.
Derivatives of BENZOIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxybenzene structure.
A di-tert-butyl PHENOL with antioxidant properties.
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.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.
A potent oxidant synthesized by the cell during its normal metabolism. Peroxynitrite is formed from the reaction of two free radicals, NITRIC OXIDE and the superoxide anion (SUPEROXIDES).
The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.
A plant genus of the family CUCURBITACEAE known for the edible fruit.
Compounds with a benzene ring fused to a thiazole ring.
Inorganic or organic compounds containing trivalent iron.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Ubiquitous, inducible, nuclear transcriptional activator that binds to enhancer elements in many different cell types and is activated by pathogenic stimuli. The NF-kappa B complex is a heterodimer composed of two DNA-binding subunits: NF-kappa B1 and relA.
Compounds containing the -SH radical.
Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.
Pregnane derivatives containing three double bonds in the ring structures.
A hemeprotein from leukocytes. Deficiency of this enzyme leads to a hereditary disorder coupled with disseminated moniliasis. It catalyzes the conversion of a donor and peroxide to an oxidized donor and water. EC 1.11.1.7.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Benzoate derivatives substituted by one or more hydroxy groups in any position on the benzene ring.
A cell line derived from cultured tumor cells.
Colorless to yellow dye that is reducible to blue or black formazan crystals by certain cells; formerly used to distinguish between nonbacterial and bacterial diseases, the latter causing neutrophils to reduce the dye; used to confirm diagnosis of chronic granulomatous disease.
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.
Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.
A nucleoside consisting of the base guanine and the sugar deoxyribose.
The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulchi. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.
Techniques used for determining the values of photometric parameters of light resulting from LUMINESCENCE.
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
Ethylenediamines are organic compounds containing two amine groups linked by a two-carbon chain, widely used in the manufacture of industrial and pharmaceutical products, including chelating agents and polymerization catalysts, but not typically used as a medication on their own.
Mixture of 2- and 3-tert-butyl-4-methoxyphenols that is used as an antioxidant in foods, cosmetics, and pharmaceuticals.
Porphyrins which are combined with a metal ion. The metal is bound equally to all four nitrogen atoms of the pyrrole rings. They possess characteristic absorption spectra which can be utilized for identification or quantitative estimation of porphyrins and porphyrin-bound compounds.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
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.
Drugs used to protect against ionizing radiation. They are usually of interest for use in radiation therapy but have been considered for other, e.g. military, purposes.
Benzopyrans saturated in the 2 and 3 positions.
A diverse group of agents, with unique chemical structures and biochemical requirements, which generate NITRIC OXIDE. These compounds have been used in the treatment of cardiovascular diseases and the management of acute myocardial infarction, acute and chronic congestive heart failure, and surgical control of blood pressure. (Adv Pharmacol 1995;34:361-81)
Hydrazines are organic compounds containing the functional group R-NH-NH2, where R represents an organic group, and are used in pharmaceuticals, agrochemicals, and rocket fuels, but can be highly toxic and carcinogenic with potential for environmental damage.
Complete or partial surgical removal of the prostate. Three primary approaches are commonly employed: suprapubic - removal through an incision above the pubis and through the urinary bladder; retropubic - as for suprapubic but without entering the urinary bladder; and transurethral (TRANSURETHRAL RESECTION OF PROSTATE).
Peroxidases are enzymes that catalyze the reduction of hydrogen peroxide to water, while oxidizing various organic and inorganic compounds, playing crucial roles in diverse biological processes including stress response, immune defense, and biosynthetic reactions.
A poisonous dipyridilium compound used as contact herbicide. Contact with concentrated solutions causes irritation of the skin, cracking and shedding of the nails, and delayed healing of cuts and wounds.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.
A family of scavenger receptors with broad polyanionic ligand binding properties that are expressed in embryonic insect MACROPHAGES.
Complex of iron atoms chelated with carbonyl ions.
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)
A plant family of the order Polygalales, subclass Rosidae, class Magnoliopsida.
A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.

Mechanism-based cancer prevention approaches: targets, examples, and the use of transgenic mice. (1/3282)

Humans are exposed to a wide variety of carcinogenic insults, including endogenous and man-made chemicals, radiation, physical agents, and viruses. The ultimate goal of carcinogenesis research is to elucidate the processes involved in the induction of human cancer so that interventions may be developed to prevent the disease, either in the general population or in susceptible subpopulations. Progress to date in the carcinogenesis field, particularly regarding the mechanisms of chemically induced cancer, has revealed several points along the carcinogenesis pathway that may be amenable to mechanism-based prevention strategies. The purpose of this review is to examine the basic mechanisms and stages of chemical carcinogenesis, with an emphasis on ways in which preventive interventions can modify those processes. Possible ways of interfering with tumor initiation events include the following: i) modifying carcinogen activation by inhibiting enzymes responsible for that activation or by direct scavenging of DNA-reactive electrophiles and free radicals; ii) enhancing carcinogen detoxification processes by altering the activity of the detoxifying enzymes; and iii) modulating certain DNA repair processes. Possible ways of blocking the processes involved in the promotion and progression stages of carcinogenesis include the following: i) scavenging of reactive oxygen species; ii) altering the expression of genes involved in cell signaling, particularly those regulating cell proliferation, apoptosis, and differentiation; and iii) decreasing inflammation. In addition, the utility for mechanism-based cancer prevention research of new animal models that are based on the overexpression or inactivation of specific cancer-related genes is examined.  (+info)

Role of iNOS in the vasodilator responses induced by L-arginine in the middle cerebral artery from normotensive and hypertensive rats. (2/3282)

1. The substrate of nitric oxide synthase (NOS), L-arginine (L-Arg, 0.01 microM - 1 mM), induced endothelium-independent relaxations in segments of middle cerebral arteries (MCAs) from normotensive Wistar-Kyoto (WKY) and hypertensive rats (SHR) precontracted with prostaglandin F2alpha (PGF2alpha). These relaxations were higher in SHR than WKY arteries. 2. L-N(G)-nitroarginine methyl ester (L-NAME) and 2-amine-5,6-dihydro-6-methyl-4H-1,3-tiazine (AMT), unspecific and inducible NOS (iNOS) inhibitors, respectively, reduced those relaxations, specially in SHR. 3. Four- and seven-hours incubation with dexamethasone reduced the relaxations in MCAs from WKY and SHR, respectively. 4. Polymyxin B and calphostin C, protein kinase C (PKC) inhibitors, reduced the L-Arg-induced relaxation. 5. Lipopolysaccharide (LPS, 7 h incubation) unaltered and inhibited these relaxations in WKY and SHR segments, respectively. LPS antagonized the effect polymyxin B in WKY and potentiated L-Arg-induced relaxations in SHR in the presence of polymyxin B. 6. The contraction induced by PGF2alpha was greater in SHR than WKY arteries. This contraction was potentiated by dexamethasone and polymyxin B although the effect of polymyxin B was higher in SHR segments. LPS reduced that contraction and antagonized dexamethasone- and polymyxin B-induced potentiation, these effects being greater in arteries from SHR. 7. These results suggest that in MCAs: (1) the induction of iNOS participates in the L-Arg relaxation and modulates the contraction to PGF2alpha; (2) that induction is partially mediated by a PKC-dependent mechanism; and (3) the involvement of iNOS in such responses is greater in the hypertensive strain.  (+info)

Effect of acute and long-term treatment with 17-beta-estradiol on the vasomotor responses in the rat aorta. (3/3282)

1. This study sought to evaluate whether the effects of acute and long-term treatment with 17-beta-estradiol on the vasomotor responses in rat aortic rings are mediated through the same mechanism. 2. Ovariectomized rats were treated daily with either 17-beta-estradiol-3-benzoate (100 microg kg(-1)) or vehicle for 1 week. 3. The effect of long-term 17-beta-estradiol treatment on the responses to cumulative doses of phenylephrine, 5-HT, calcium, potassium and 17-beta-estradiol was determined in aortic rings. In the same rings, the effect of acute exposure to 17-beta-estradiol (5 and 10 microM) on the dose response curves for phenylephrine, 5-HT, calcium, potassium and acetylcholine were estimated. The measurements were made in rings with and without intact endothelium. The tone-related basal release of nitric oxide (NO) was measured in rings with intact endothelium. 4. Long-term 17-beta-estradiol treatment reduced the maximum developed contraction to all contracting agents studied. This effect was abolished in endothelium denuded vessels. Acute 17-beta-estradiol treatment also reduced maximal contraction. This effect, however, was independent of the endothelium. 5. Long-term 17-beta-estradiol treatment significantly increased the ability of the rings to dilate in response to acetylcholine whereas acute exposure to 17-beta-estradiol had no effect. The tone-related release of NO was significantly increased after long-term exposure to 17-beta-estradiol. 6. In conclusion, this study indicate that the acute and long-term effects of 17-beta-estradiol in the rat aorta are mediated through different mechanisms. The long-term effect is mediated through the endothelium most likely by increasing NO release. In contrast, the acute effect of 17-beta-estradiol seems to be through an effect on the vascular smooth muscle cells.  (+info)

[3H]-Mesulergine labels 5-HT7 sites in rat brain and guinea-pig ileum but not rat jejunum. (4/3282)

1. The primary aim of this investigation was to determine whether binding sites corresponding to the 5-HT7 receptor could be detected in smooth muscle of the rat jejunum. Binding studies in rat brain (whole brain minus cerebellum) and guinea-pig ileal longitudinal muscle were also undertaken in order to compare the binding characteristics of these tissues. Studies were performed using [3H]-mesulergine, as it has a high affinity for 5-HT7 receptors. 2. In the rat brain and guinea-pig ileum, pKD values for [3H]-mesulergine of 8.0 +/- 0.04 and 7.9 +/- 0.11 (n = 3) and Bmax values of 9.9 +/- 0.3 and 21.5 +/- 4.9 fmol mg(-1) protein were obtained respectively, but no binding was detected in the rat jejunum. [3H]-mesulergine binding in the rat brain and guinea-pig ileum was displaced with the agonists 5-carboxamidotryptamine (5-CT) > 5-hydroxytryptamine (5-HT) > or = 5-methoxytryptamine (5-MeOT) > sumatriptan and the antagonists risperidone > or = LSD > or = metergoline > ritanserin > > pindolol. 3. Despite the lack of [3H]-mesulergine binding in the rat jejunum, functional studies undertaken revealed a biphasic contractile response to 5-HT which was partly blocked by ondansetron (1 microM). The residual response was present in over 50% of tissues studied and was found to be inhibited by risperidone > LSD > metergoline > mesulergine = ritanserin > pindolol, but was unaffected by RS 102221 (3 microM), cinanserin (30 nM), yohimbine (0.1 microM) and GR 113808 (1 microM). In addition, the agonist order of potency was 5-CT > 5-HT > 5-MeOT > sumatriptan. 4. In conclusion, binding studies performed with [3H]-mesulergine were able to detect 5-HT7 sites in rat brain and guinea-pig ileum, but not in rat jejunum, where a functional 5-HT7-like receptor was present.  (+info)

Effects of pyrogallol, hydroquinone and duroquinone on responses to nitrergic nerve stimulation and NO in the rat anococcygeus muscle. (5/3282)

1. The hypothesis that endogenous superoxide dismutase (SOD) protects the nitrergic transmitter from inactivation by superoxide and that this explains the lack of sensitivity of the transmitter to superoxide generators was tested in the rat isolated anococcygeus muscle. 2. Responses to nitrergic nerve stimulation or to NO were not significantly affected by exogenous SOD or by the Cu/Zn SOD inhibitor diethyldithiocarbamic acid (DETCA). 3. Hydroquinone produced a concentration-dependent reduction of responses to NO with an IC50 of 27 microM, and higher concentrations reduced relaxant responses to nitrergic nerve stimulation with an IC50 of 612 microM. The effects of hydroquinone were only slightly reversed by SOD, so it does not appear to be acting as a superoxide generator. 4. Pyrogallol produced a concentration-dependent reduction in responses to NO with an IC50 value of 39 microM and this effect was reversed by SOD (100-1000 u ml(-1)). Pyrogallol did not affect responses to nitrergic nerve stimulation. Treatment with DETCA did not alter the differentiating action of pyrogallol. 5. Duroquinone produced a concentration-dependent reduction of relaxations to NO with an IC50 value of 240 microM and 100 microM slightly decreased nitrergic relaxations. After treatment with DETCA, duroquinone produced greater reductions of relaxant responses to NO and to nitrergic stimulation, the IC50 values being 8.5 microM for NO and 40 microM for nitrergic nerve stimulation: these reductions were reversed by SOD. 6. The findings do not support the hypothesis that the presence of Cu/Zn SOD explains the greater susceptibility of NO than the nitrergic transmitter to the superoxide generator pyrogallol, but suggest that it may play a role in the effects of duroquinone.  (+info)

The influence of NO synthase inhibitor and free oxygen radicals scavenger--methylene blue--on streptozotocin-induced diabetes in rats. (6/3282)

The excessive production of nitric oxide (NO) and the subsequent increase of local oxidative stress is suggested as one of the pathophysiological mechanisms of streptozotocin-induced diabetes. It was reported that the administration of NO synthase inhibitors partially attenuated the development of streptozotocin-induced diabetes and reduced hyperglycaemia. Here we have studied the influence of methylene blue, which combines the properties of NO synthase inhibitor with antioxidant effects. The experiments were performed on male rats divided into four groups: control, diabetic (single dose of 70 mg of streptozotocin/kg i.p.), methylene blue (50 mg/kg in the food) and diabetic simultaneously fed with methylene blue. After 45 days the experiments were discontinued by decapitation. Serum glycaemia, glycated haemoglobin and oxidative stress parameters (plasma malondialdehyde concentration and erythrocyte superoxide dismutase activity) were significantly higher in the diabetic group. Simultaneous methylene blue administration partially reduced glycaemia and glycated haemoglobin, but did not decrease oxidative stress. We conclude that NO synthase inhibitor methylene blue partially attenuates the development of streptozotocin-induced diabetes in male rats, but does not reduce the development of oxidative stress in the diabetic group.  (+info)

Regulation of JNK signaling by GSTp. (7/3282)

Studies of low basal Jun N-terminal kinase (JNK) activity in non-stressed cells led us to identify a JNK inhibitor that was purified and identified as glutathione S-transferase Pi (GSTp) and was characterized as a JNK-associated protein. UV irradiation or H2O2 treatment caused GSTp oligomerization and dissociation of the GSTp-JNK complex, indicating that it is the monomeric form of GSTp that elicits JNK inhibition. Addition of purified GSTp to the Jun-JNK complex caused a dose-dependent inhibition of JNK activity. Conversely, immunodepleting GSTp from protein extracts attenuated JNK inhibition. Furthermore, JNK activity was increased in the presence of specific GSTp inhibitors and a GSTp-derived peptide. Forced expression of GSTp decreased MKK4 and JNK phosphorylation which coincided with decreased JNK activity, increased c-Jun ubiquitination and decreased c-Jun-mediated transcription. Co-transfection of MEKK1 and GSTp restored MKK4 phosphorylation but did not affect GSTp inhibition of JNK activity, suggesting that the effect of GSTp on JNK is independent of the MEKK1-MKK4 module. Mouse embryo fibroblasts from GSTp-null mice exhibited a high basal level of JNK activity that could be reduced by forced expression of GSTp cDNA. In demonstrating the relationships between GSTp expression and its association with JNK, our findings provide new insight into the regulation of stress kinases.  (+info)

Salicylate inhibits LDL oxidation initiated by superoxide/nitric oxide radicals. (8/3282)

Simultaneously produced superoxide/nitric oxide radicals (O2*-/NO*) could form peroxynitrite (OONO-) which has been found to cause atherogenic, i.e. oxidative modification of LDL. Aromatic hydroxylation and nitration of the aspirin metabolite salicylate by OONO- has been reported. Therefore we tested if salicylate may be able to protect LDL from oxidation by O2*-/NO* by scavenging the OONO reactive decomposition products. When LDL was exposed to simultaneously produced O2*-/NO* using the sydnonimine SIN-1, salicylate exerted an inhibitory effect on LDL oxidation as measured by TBARS and lipid hydroperoxide formation and alteration in electrophoretic mobility of LDL. The cytotoxic effect of SIN-1 pre-oxidised LDL to endothelial cells was also diminished when salicylate was present during SIN-1 treatment of LDL. Spectrophotometric analysis revealed that salicylate was converted to dihydroxybenzoic acid (DHBA) derivatives in the presence of SIN-1. 2,3- and 2,5-DHBA were even more effective to protect LDL from oxidation by O2*-/NO*. Because O2*-/NO* can occur in vivo, the results may indicate that salicylate could act as an efficacious inhibitor of O2*-/NO* initiated atherogenic LDL modification, thus further supporting the rationale of aspirin medication regarding cardiovascular diseases.  (+info)

Free radical scavengers, also known as antioxidants, are substances that neutralize or stabilize free radicals. Free radicals are highly reactive atoms or molecules with unpaired electrons, capable of causing damage to cells and tissues in the body through a process called oxidative stress. Antioxidants donate an electron to the free radical, thereby neutralizing it and preventing it from causing further damage. They can be found naturally in foods such as fruits, vegetables, and nuts, or they can be synthesized and used as dietary supplements. Examples of antioxidants include vitamins C and E, beta-carotene, and selenium.

Free radicals are molecules or atoms that have one or more unpaired electrons in their outermost shell, making them highly reactive. They can be formed naturally in the body through processes such as metabolism and exercise, or they can come from external sources like pollution, radiation, and certain chemicals. Free radicals can cause damage to cells and contribute to the development of various diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. Antioxidants are substances that can neutralize free radicals and help protect against their harmful effects.

Antipyrine is a chemical compound that was commonly used as a fever reducer and pain reliever in the past. It is a type of phenylpyrazole antipyretic and analgesic. However, due to its potential for causing liver damage and other side effects, it has largely been replaced by other medications and is not widely used in modern medicine.

The medical definition of Antipyrine refers to this specific chemical compound with the formula C11H13N3O2, and not to any broader category of drugs or substances. It is a white crystalline powder that is soluble in alcohol, chloroform, and ether, but insoluble in water.

Antipyrine was first synthesized in 1883 and was widely used as a fever reducer and pain reliever until the mid-20th century. However, its use declined due to concerns about its safety profile, including the potential for liver damage, skin reactions, and other side effects.

Today, Antipyrine is still used in some medical applications, such as in the measurement of earwax conductivity as a way to assess hearing function. It may also be used in some topical creams and ointments for pain relief. However, its use as a systemic medication is generally not recommended due to its potential for causing harm.

A hydroxyl radical is defined in biochemistry and medicine as an extremely reactive species, characterized by the presence of an oxygen atom bonded to a hydrogen atom (OH-). It is formed when a water molecule (H2O) is split into a hydroxide ion (OH-) and a hydrogen ion (H+) in the process of oxidation.

In medical terms, hydroxyl radicals are important in understanding free radical damage and oxidative stress, which can contribute to the development of various diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. They are also involved in the body's natural defense mechanisms against pathogens. However, an overproduction of hydroxyl radicals can cause damage to cellular components such as DNA, proteins, and lipids, leading to cell dysfunction and death.

Cyclic N-oxides are a class of organic compounds that contain a cyclic structure with a nitrogen atom bonded to an oxygen atom as an N-oxide. An N-oxide is a compound in which the nitrogen atom has a positive charge and the oxygen atom has a negative charge, forming a polar covalent bond. In cyclic N-oxides, this N-O group is part of a ring structure, which can be composed of various combinations of carbon, nitrogen, and other atoms. These compounds have been studied for their potential use in pharmaceuticals, agrochemicals, and materials science.

Antioxidants are substances that can prevent or slow damage to cells caused by free radicals, which are unstable molecules that the body produces as a reaction to environmental and other pressures. Antioxidants are able to neutralize free radicals by donating an electron to them, thus stabilizing them and preventing them from causing further damage to the cells.

Antioxidants can be found in a variety of foods, including fruits, vegetables, nuts, and grains. Some common antioxidants include vitamins C and E, beta-carotene, and selenium. Antioxidants are also available as dietary supplements.

In addition to their role in protecting cells from damage, antioxidants have been studied for their potential to prevent or treat a number of health conditions, including cancer, heart disease, and age-related macular degeneration. However, more research is needed to fully understand the potential benefits and risks of using antioxidant supplements.

Tiopronin is a medication that belongs to a class of drugs called mucolytic agents. It works by breaking down mucus in the respiratory tract, making it easier to cough up and clear the airways. Tiopronin is also known as tiopronin sodium or Thiola®.

In addition to its use as a mucolytic agent, tiopronin has been found to be effective in reducing the formation of cystine kidney stones in patients with a rare genetic disorder called cystinuria. It works by binding to cystine in the urine and preventing it from forming into crystals or stones.

Tiopronin is available as a tablet or oral solution and is typically taken several times a day, with dosing adjusted based on the patient's individual needs and response to treatment. Common side effects of tiopronin include stomach upset, loss of appetite, and rash.

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.

Scavenger receptors are a class of cell surface receptors that play a crucial role in the recognition and clearance of various biomolecules, including modified self-molecules, pathogens, and apoptotic cells. These receptors are expressed mainly by phagocytic cells such as macrophages and dendritic cells, but they can also be found on other cell types, including endothelial cells and smooth muscle cells.

Scavenger receptors have broad specificity and can bind to a wide range of ligands, including oxidized low-density lipoprotein (oxLDL), polyanionic molecules, advanced glycation end products (AGEs), and pathogen-associated molecular patterns (PAMPs). The binding of ligands to scavenger receptors triggers various cellular responses, such as phagocytosis, endocytosis, signaling cascades, and the production of cytokines and chemokines.

Scavenger receptors are classified into several families based on their structural features and ligand specificity, including:

1. Class A (SR-A): This family includes SR-AI, SR-AII, and MARCO, which bind to oxLDL, bacteria, and apoptotic cells.
2. Class B (SR-B): This family includes SR-BI, CD36, and LIMPII, which bind to lipoproteins, phospholipids, and pathogens.
3. Class C (SR-C): This family includes DEC-205, MRC1, and LOX-1, which bind to various ligands, including apoptotic cells, bacteria, and oxLDL.
4. Class D (SR-D): This family includes SCARF1, which binds to PAMPs and damage-associated molecular patterns (DAMPs).
5. Class E (SR-E): This family includes CXCL16, which binds to chemokine CXCR6 and phosphatidylserine.

Scavenger receptors play a critical role in maintaining tissue homeostasis by removing damaged or altered molecules and cells, modulating immune responses, and regulating lipid metabolism. Dysregulation of scavenger receptor function has been implicated in various pathological conditions, including atherosclerosis, inflammation, infection, and cancer.

Medical Definition:

Superoxide dismutase (SOD) is an enzyme that catalyzes the dismutation of superoxide radicals (O2-) into oxygen (O2) and hydrogen peroxide (H2O2). This essential antioxidant defense mechanism helps protect the body's cells from damage caused by reactive oxygen species (ROS), which are produced during normal metabolic processes and can lead to oxidative stress when their levels become too high.

There are three main types of superoxide dismutase found in different cellular locations:
1. Copper-zinc superoxide dismutase (CuZnSOD or SOD1) - Present mainly in the cytoplasm of cells.
2. Manganese superoxide dismutase (MnSOD or SOD2) - Located within the mitochondrial matrix.
3. Extracellular superoxide dismutase (EcSOD or SOD3) - Found in the extracellular spaces, such as blood vessels and connective tissues.

Imbalances in SOD levels or activity have been linked to various pathological conditions, including neurodegenerative diseases, cancer, and aging-related disorders.

Oxidative stress is defined as an imbalance between the production of reactive oxygen species (free radicals) and the body's ability to detoxify them or repair the damage they cause. This imbalance can lead to cellular damage, oxidation of proteins, lipids, and DNA, disruption of cellular functions, and activation of inflammatory responses. Prolonged or excessive oxidative stress has been linked to various health conditions, including cancer, cardiovascular diseases, neurodegenerative disorders, and aging-related diseases.

Lipid peroxidation is a process in which free radicals, such as reactive oxygen species (ROS), steal electrons from lipids containing carbon-carbon double bonds, particularly polyunsaturated fatty acids (PUFAs). This results in the formation of lipid hydroperoxides, which can decompose to form a variety of compounds including reactive carbonyl compounds, aldehydes, and ketones.

Malondialdehyde (MDA) is one such compound that is commonly used as a marker for lipid peroxidation. Lipid peroxidation can cause damage to cell membranes, leading to changes in their fluidity and permeability, and can also result in the modification of proteins and DNA, contributing to cellular dysfunction and ultimately cell death. It is associated with various pathological conditions such as atherosclerosis, neurodegenerative diseases, and cancer.

I am not a medical expert, but I can provide some information that may be helpful. "Picrates" is not a term commonly used in medical definitions. Instead, it is a term used in chemistry to refer to salts of picric acid (2,4,6-trinitrophenol), which was once used as a yellow dye and explosive.

Picric acid has been used historically in some medical applications, such as a component in certain topical antiseptics and in histological staining procedures. However, its use in modern medicine is quite limited due to its high sensitivity to impact, heat, and friction, which makes it potentially dangerous to handle.

Therefore, it's important to note that "picrates" is not a medical term per se but rather a chemical one, and any medical application of picric acid or its salts would be highly specialized and unlikely to be encountered in most healthcare settings.

Scavenger receptors, class A, are a group of membrane-bound proteins found on the surface of various cell types, including macrophages, dendritic cells, and endothelial cells. These receptors play an essential role in recognizing and removing modified or damaged self and foreign molecules from the body.

Class A scavenger receptors include three members: SR-A1 (also known as Macrophage Scavenger Receptor 1 or MSR1), SR-A2 (also known as SCARA2 or MSR2), and SR-A3 (also known as SCARA3). These receptors have a wide range of ligands, including oxidized low-density lipoprotein (oxLDL), polyanionic molecules, advanced glycation end products (AGEs), and pathogens.

SR-A1 is the best characterized among the three members and has been implicated in various physiological and pathological processes, such as atherosclerosis, immune response, and neurodegenerative disorders. SR-A2 and SR-A3 have overlapping functions with SR-A1 but are less well studied.

Overall, scavenger receptors, class A, contribute to the maintenance of tissue homeostasis by clearing cellular debris and modulating immune responses. However, dysregulation of these receptors has been associated with several diseases, making them potential therapeutic targets for various pathological conditions.

Hydrogen peroxide (H2O2) is a colorless, odorless, clear liquid with a slightly sweet taste, although drinking it is harmful and can cause poisoning. It is a weak oxidizing agent and is used as an antiseptic and a bleaching agent. In diluted form, it is used to disinfect wounds and kill bacteria and viruses on the skin; in higher concentrations, it can be used to bleach hair or remove stains from clothing. It is also used as a propellant in rocketry and in certain industrial processes. Chemically, hydrogen peroxide is composed of two hydrogen atoms and two oxygen atoms, and it is structurally similar to water (H2O), with an extra oxygen atom. This gives it its oxidizing properties, as the additional oxygen can be released and used to react with other substances.

Hydroxides are inorganic compounds that contain the hydroxide ion (OH−). They are formed when a base, which is an electron pair donor, reacts with water. The hydroxide ion consists of one oxygen atom and one hydrogen atom, and it carries a negative charge. Hydroxides are basic in nature due to their ability to donate hydroxide ions in solution, which increases the pH and makes the solution more alkaline. Common examples of hydroxides include sodium hydroxide (NaOH), potassium hydroxide (KOH), and calcium hydroxide (Ca(OH)2). They have various applications in industry, medicine, and research.

Catalase is a type of enzyme that is found in many living organisms, including humans. Its primary function is to catalyze the decomposition of hydrogen peroxide (H2O2) into water (H2O) and oxygen (O2). This reaction helps protect cells from the harmful effects of hydrogen peroxide, which can be toxic at high concentrations.

The chemical reaction catalyzed by catalase can be represented as follows:

H2O2 + Catalase → H2O + O2 + Catalase

Catalase is a powerful antioxidant enzyme that plays an important role in protecting cells from oxidative damage. It is found in high concentrations in tissues that produce or are exposed to hydrogen peroxide, such as the liver, kidneys, and erythrocytes (red blood cells).

Deficiency in catalase activity has been linked to several diseases, including cancer, neurodegenerative disorders, and aging. On the other hand, overexpression of catalase has been shown to have potential therapeutic benefits in various disease models, such as reducing inflammation and oxidative stress.

Acetylcysteine is a medication that is used for its antioxidant effects and to help loosen thick mucus in the lungs. It is commonly used to treat conditions such as chronic bronchitis, emphysema, and cystic fibrosis. Acetylcysteine is also known by the brand names Mucomyst and Accolate. It works by thinning and breaking down mucus in the airways, making it easier to cough up and clear the airways. Additionally, acetylcysteine is an antioxidant that helps to protect cells from damage caused by free radicals. It is available as a oral tablet, liquid, or inhaled medication.

Ascorbic acid is the chemical name for Vitamin C. It is a water-soluble vitamin that is essential for human health. Ascorbic acid is required for the synthesis of collagen, a protein that plays a role in the structure of bones, tendons, ligaments, and blood vessels. It also functions as an antioxidant, helping to protect cells from damage caused by free radicals.

Ascorbic acid cannot be produced by the human body and must be obtained through diet or supplementation. Good food sources of vitamin C include citrus fruits, strawberries, bell peppers, broccoli, and spinach.

In the medical field, ascorbic acid is used to treat or prevent vitamin C deficiency and related conditions, such as scurvy. It may also be used in the treatment of various other health conditions, including common cold, cancer, and cardiovascular disease, although its effectiveness for these uses is still a matter of scientific debate.

Thiourea is not a medical term, but a chemical compound. It's a colorless crystalline solid with the formula SC(NH2)2. Thiourea is used in some industrial processes and can be found in some laboratory reagents. It has been studied for its potential effects on certain medical conditions, such as its ability to protect against radiation damage, but it is not a medication or a treatment that is currently in clinical use.

Scavenger receptors, class B (SR-B) are a type of scavenger receptors that play a crucial role in the cellular uptake and metabolism of lipids, particularly modified low-density lipoproteins (LDL), high-density lipoproteins (HDL), and other lipid-soluble molecules. They are membrane-bound glycoproteins that contain an extracellular domain with a characteristic structure, including cysteine-rich repeats and transmembrane domains.

The best-characterized member of this class is SR-B1 (also known as CD36b, SCARB1), which is widely expressed in various tissues, such as the liver, steroidogenic organs, macrophages, and endothelial cells. SR-B1 selectively binds to HDL and facilitates the transfer of cholesteryl esters from HDL particles into cells while allowing HDL to maintain its structural integrity and continue its function in reverse cholesterol transport.

SR-B1 has also been implicated in the uptake and degradation of oxidized LDL, contributing to the development of atherosclerosis. Additionally, SR-B1 is involved in several other cellular processes, including innate immunity, inflammation, and angiogenesis.

Other members of class B scavenger receptors include SR-BI, SR-B2 (also known as CLA-1 or LIMPII), SR-B3 (also known as CD36c or SCARB2), and SR-B4 (also known as CXorf24). These receptors have distinct expression patterns and functions but share structural similarities with SR-BI.

In summary, scavenger receptors, class B, are a group of membrane-bound glycoproteins that facilitate the cellular uptake and metabolism of lipids, particularly modified LDL and HDL particles. They play essential roles in maintaining lipid homeostasis and have implications in various pathological conditions, such as atherosclerosis and inflammation.

Nitrogen oxides (NOx) are a group of highly reactive gases, primarily composed of nitric oxide (NO) and nitrogen dioxide (NO2). They are formed during the combustion of fossil fuels, such as coal, oil, gas, or biomass, and are emitted from various sources, including power plants, industrial boilers, transportation vehicles, and residential heating systems. Exposure to NOx can have adverse health effects, particularly on the respiratory system, and contribute to the formation of harmful air pollutants like ground-level ozone and fine particulate matter.

Malondialdehyde (MDA) is a naturally occurring organic compound that is formed as a byproduct of lipid peroxidation, a process in which free radicals or reactive oxygen species react with polyunsaturated fatty acids. MDA is a highly reactive aldehyde that can modify proteins, DNA, and other biomolecules, leading to cellular damage and dysfunction. It is often used as a marker of oxidative stress in biological systems and has been implicated in the development of various diseases, including cancer, cardiovascular disease, and neurodegenerative disorders.

Superoxides are partially reduced derivatives of oxygen that contain one extra electron, giving them an overall charge of -1. They are highly reactive and unstable, with the most common superoxide being the hydroxyl radical (•OH-) and the superoxide anion (O2-). Superoxides are produced naturally in the body during metabolic processes, particularly within the mitochondria during cellular respiration. They play a role in various physiological processes, but when produced in excess or not properly neutralized, they can contribute to oxidative stress and damage to cells and tissues, potentially leading to the development of various diseases such as cancer, atherosclerosis, and neurodegenerative disorders.

Oxidation-Reduction (redox) reactions are a type of chemical reaction involving a transfer of electrons between two species. The substance that loses electrons in the reaction is oxidized, and the substance that gains electrons is reduced. Oxidation and reduction always occur together in a redox reaction, hence the term "oxidation-reduction."

In biological systems, redox reactions play a crucial role in many cellular processes, including energy production, metabolism, and signaling. The transfer of electrons in these reactions is often facilitated by specialized molecules called electron carriers, such as nicotinamide adenine dinucleotide (NAD+/NADH) and flavin adenine dinucleotide (FAD/FADH2).

The oxidation state of an element in a compound is a measure of the number of electrons that have been gained or lost relative to its neutral state. In redox reactions, the oxidation state of one or more elements changes as they gain or lose electrons. The substance that is oxidized has a higher oxidation state, while the substance that is reduced has a lower oxidation state.

Overall, oxidation-reduction reactions are fundamental to the functioning of living organisms and are involved in many important biological processes.

"Spin labels" are a term used in the field of magnetic resonance, including nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR). They refer to molecules or atoms that have been chemically attached to a system of interest and possess a stable, unpaired electron. This unpaired electron behaves like a tiny magnet and can be manipulated using magnetic fields and radiofrequency pulses in EPR experiments. The resulting changes in the electron's spin state can provide information about the local environment, dynamics, and structure of the system to which it is attached. Spin labels are often used in biochemistry and materials science to study complex biological systems or materials at the molecular level.

Imidazolines are a class of compounds with a heterocyclic ring containing two nitrogen atoms, one of which is part of an imidazole ring. In the context of medicine and pharmacology, imidazolines are commonly used as decongestants, vasoconstrictors, and as ingredients in some over-the-counter and prescription medications for the treatment of conditions such as allergic rhinitis, nasal congestion, and redness of the eyes.

Imidazoline compounds work by stimulating alpha-adrenergic receptors, which leads to vasoconstriction and decreased blood flow in the affected area. This can help to relieve symptoms such as nasal congestion and red, swollen eyes. However, it is important to note that imidazoline compounds can also have systemic effects when absorbed into the bloodstream, and may cause side effects such as dizziness, dry mouth, and sedation.

Some examples of imidazoline compounds used in medicine include tetrahydrozoline, oxymetazoline, and naphazoline. These compounds are available in various forms, including nasal sprays, eye drops, and oral medications. It is important to follow the instructions for use carefully and to talk to a healthcare provider if you have any questions or concerns about using imidazoline-containing products.

Deferoxamine is a medication used to treat iron overload, which can occur due to various reasons such as frequent blood transfusions or excessive iron intake. It works by binding to excess iron in the body and promoting its excretion through urine. This helps to prevent damage to organs such as the heart and liver that can be caused by high levels of iron.

Deferoxamine is an injectable medication that is typically administered intravenously or subcutaneously, depending on the specific regimen prescribed by a healthcare professional. It may also be used in combination with other medications to manage iron overload more effectively.

It's important to note that deferoxamine should only be used under the guidance of a medical professional, as improper use or dosing can lead to serious side effects or complications.

Electron Spin Resonance (ESR) Spectroscopy, also known as Electron Paramagnetic Resonance (EPR) Spectroscopy, is a technique used to investigate materials with unpaired electrons. It is based on the principle of absorption of energy by the unpaired electrons when they are exposed to an external magnetic field and microwave radiation.

In this technique, a sample is placed in a magnetic field and microwave radiation is applied. The unpaired electrons in the sample absorb energy and change their spin state when the energy of the microwaves matches the energy difference between the spin states. This absorption of energy is recorded as a function of the magnetic field strength, producing an ESR spectrum.

ESR spectroscopy can provide information about the number, type, and behavior of unpaired electrons in a sample, as well as the local environment around the electron. It is widely used in physics, chemistry, and biology to study materials such as free radicals, transition metal ions, and defects in solids.

Xanthine oxidase is an enzyme that catalyzes the oxidation of xanthine to uric acid, which is the last step in purine metabolism. It's a type of molybdenum-containing oxidoreductase that generates reactive oxygen species (ROS) during its reaction mechanism.

The enzyme exists in two interconvertible forms: an oxidized state and a reduced state. The oxidized form, called xanthine oxidase, reduces molecular oxygen to superoxide and hydrogen peroxide, while the reduced form, called xanthine dehydrogenase, reduces NAD+ to NADH.

Xanthine oxidase is found in various tissues, including the liver, intestines, and milk. An overproduction of uric acid due to increased activity of xanthine oxidase can lead to hyperuricemia, which may result in gout or kidney stones. Some medications and natural compounds are known to inhibit xanthine oxidase, such as allopurinol and febuxostat, which are used to treat gout and prevent the formation of uric acid stones in the kidneys.

Melatonin is a hormone that is produced by the pineal gland in the brain. It helps regulate sleep-wake cycles and is often referred to as the "hormone of darkness" because its production is stimulated by darkness and inhibited by light. Melatonin plays a key role in synchronizing the circadian rhythm, the body's internal clock that regulates various biological processes over a 24-hour period.

Melatonin is primarily released at night, and its levels in the blood can rise and fall in response to changes in light and darkness in an individual's environment. Supplementing with melatonin has been found to be helpful in treating sleep disorders such as insomnia, jet lag, and delayed sleep phase syndrome. It may also have other benefits, including antioxidant properties and potential uses in the treatment of certain neurological conditions.

It is important to note that while melatonin supplements are available over-the-counter in many countries, they should still be used under the guidance of a healthcare professional, as their use can have potential side effects and interactions with other medications.

Oxygen is a colorless, odorless, tasteless gas that constitutes about 21% of the earth's atmosphere. It is a crucial element for human and most living organisms as it is vital for respiration. Inhaled oxygen enters the lungs and binds to hemoglobin in red blood cells, which carries it to tissues throughout the body where it is used to convert nutrients into energy and carbon dioxide, a waste product that is exhaled.

Medically, supplemental oxygen therapy may be provided to patients with conditions such as chronic obstructive pulmonary disease (COPD), pneumonia, heart failure, or other medical conditions that impair the body's ability to extract sufficient oxygen from the air. Oxygen can be administered through various devices, including nasal cannulas, face masks, and ventilators.

Propionophenones are a group of chemical compounds that contain a propanone (or methyl ketone) substituent and a phenyl group. In medical terms, some propionophenones have been used as pharmaceuticals, such as the antipsychotic drug perphenazine. However, it's important to note that not all propionophenones have medicinal uses, and some may even be harmful or toxic. Therefore, specific propionophenones should be evaluated on a case-by-case basis for their medical relevance or potential hazards.

Lipid peroxides are chemical compounds that form when lipids (fats or fat-like substances) oxidize. This process, known as lipid peroxidation, involves the reaction of lipids with oxygen in a way that leads to the formation of hydroperoxides and various aldehydes, such as malondialdehyde.

Lipid peroxidation is a naturally occurring process that can also be accelerated by factors such as exposure to radiation, certain chemicals, or enzymatic reactions. It plays a role in many biological processes, including cell signaling and regulation of gene expression, but it can also contribute to the development of various diseases when it becomes excessive.

Examples of lipid peroxides include phospholipid hydroperoxides, cholesteryl ester hydroperoxides, and triglyceride hydroperoxides. These compounds are often used as markers of oxidative stress in biological systems and have been implicated in the pathogenesis of atherosclerosis, cancer, neurodegenerative diseases, and other conditions associated with oxidative damage.

Medical Definition of Vitamin E:

Vitamin E is a fat-soluble antioxidant that plays a crucial role in protecting your body's cells from damage caused by free radicals, which are unstable molecules produced when your body breaks down food or is exposed to environmental toxins like cigarette smoke and radiation. Vitamin E is also involved in immune function, DNA repair, and other metabolic processes.

It is a collective name for a group of eight fat-soluble compounds that include four tocopherols and four tocotrienols. Alpha-tocopherol is the most biologically active form of vitamin E in humans and is the one most commonly found in supplements.

Vitamin E deficiency is rare but can occur in people with certain genetic disorders or who cannot absorb fat properly. Symptoms of deficiency include nerve and muscle damage, loss of feeling in the arms and legs, muscle weakness, and vision problems.

Food sources of vitamin E include vegetable oils (such as sunflower, safflower, and wheat germ oil), nuts and seeds (like almonds, peanuts, and sunflower seeds), and fortified foods (such as cereals and some fruit juices).

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

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

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

Biphenyl compounds, also known as diphenyls, are a class of organic compounds consisting of two benzene rings linked by a single carbon-carbon bond. The chemical structure of biphenyl compounds can be represented as C6H5-C6H5. These compounds are widely used in the industrial sector, including as intermediates in the synthesis of other chemicals, as solvents, and in the production of plastics and dyes. Some biphenyl compounds also have biological activity and can be found in natural products. For example, some plant-derived compounds that belong to this class have been shown to have anti-inflammatory, antioxidant, and anticancer properties.

Allopurinol is a medication used to treat chronic gout and certain types of kidney stones. It works by reducing the production of uric acid in the body, which is the substance that can cause these conditions when it builds up in high levels. Allopurinol is a xanthine oxidase inhibitor, meaning it blocks an enzyme called xanthine oxidase from converting purines into uric acid. By doing this, allopurinol helps to lower the levels of uric acid in the body and prevent the formation of new kidney stones or gout attacks.

It is important to note that allopurinol can have side effects, including rash, stomach upset, and liver or kidney problems. It may also interact with other medications, so it is essential to inform your healthcare provider of any other drugs you are taking before starting allopurinol. Your healthcare provider will determine the appropriate dosage and monitoring schedule based on your individual needs and medical history.

Glutathione is a tripeptide composed of three amino acids: cysteine, glutamic acid, and glycine. It is a vital antioxidant that plays an essential role in maintaining cellular health and function. Glutathione helps protect cells from oxidative stress by neutralizing free radicals, which are unstable molecules that can damage cells and contribute to aging and diseases such as cancer, heart disease, and dementia. It also supports the immune system, detoxifies harmful substances, and regulates various cellular processes, including DNA synthesis and repair.

Glutathione is found in every cell of the body, with particularly high concentrations in the liver, lungs, and eyes. The body can produce its own glutathione, but levels may decline with age, illness, or exposure to toxins. As such, maintaining optimal glutathione levels through diet, supplementation, or other means is essential for overall health and well-being.

Reperfusion injury is a complex pathophysiological process that occurs when blood flow is restored to previously ischemic tissues, leading to further tissue damage. This phenomenon can occur in various clinical settings such as myocardial infarction (heart attack), stroke, or peripheral artery disease after an intervention aimed at restoring perfusion.

The restoration of blood flow leads to the generation of reactive oxygen species (ROS) and inflammatory mediators, which can cause oxidative stress, cellular damage, and activation of the immune system. This results in a cascade of events that may lead to microvascular dysfunction, capillary leakage, and tissue edema, further exacerbating the injury.

Reperfusion injury is an important consideration in the management of ischemic events, as interventions aimed at restoring blood flow must be carefully balanced with potential harm from reperfusion injury. Strategies to mitigate reperfusion injury include ischemic preconditioning (exposing the tissue to short periods of ischemia before a prolonged ischemic event), ischemic postconditioning (applying brief periods of ischemia and reperfusion after restoring blood flow), remote ischemic preconditioning (ischemia applied to a distant organ or tissue to protect the target organ), and pharmacological interventions that scavenge ROS, reduce inflammation, or improve microvascular function.

A plant extract is a preparation containing chemical constituents that have been extracted from a plant using a solvent. The resulting extract may contain a single compound or a mixture of several compounds, depending on the extraction process and the specific plant material used. These extracts are often used in various industries including pharmaceuticals, nutraceuticals, cosmetics, and food and beverage, due to their potential therapeutic or beneficial properties. The composition of plant extracts can vary widely, and it is important to ensure their quality, safety, and efficacy before use in any application.

Medical definitions of "oxidants" refer to them as oxidizing agents or substances that can gain electrons and be reduced. They are capable of accepting electrons from other molecules in chemical reactions, leading to the production of oxidation products. In biological systems, oxidants play a crucial role in various cellular processes such as energy production and immune responses. However, an imbalance between oxidant and antioxidant levels can lead to a state of oxidative stress, which has been linked to several diseases, including cancer, cardiovascular disease, and neurodegenerative disorders. Examples of oxidants include reactive oxygen species (ROS), such as superoxide anion, hydrogen peroxide, and hydroxyl radical, as well as reactive nitrogen species (RNS), such as nitric oxide and peroxynitrite.

I'm sorry for any confusion, but "sulfonic acids" are not a medical term. They are a type of compound in chemistry, specifically strong organic acids that contain the functional group -SO3H. Sulfonic acids are widely used in industry and research, including the production of detergents, dyes, and pharmaceuticals.

If you have any questions related to medical terminology or concepts, please don't hesitate to ask!

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

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

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

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.

Neuroprotective agents are substances that protect neurons or nerve cells from damage, degeneration, or death caused by various factors such as trauma, inflammation, oxidative stress, or excitotoxicity. These agents work through different mechanisms, including reducing the production of free radicals, inhibiting the release of glutamate (a neurotransmitter that can cause cell damage in high concentrations), promoting the growth and survival of neurons, and preventing apoptosis (programmed cell death). Neuroprotective agents have been studied for their potential to treat various neurological disorders, including stroke, traumatic brain injury, Parkinson's disease, Alzheimer's disease, and multiple sclerosis. However, more research is needed to fully understand their mechanisms of action and to develop effective therapies.

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.

A melatonin receptor is a type of G protein-coupled receptor (GPCR) that binds to the hormone melatonin, which plays a crucial role in regulating sleep-wake cycles and other physiological functions. There are two main types of melatonin receptors: MT1 (also known as Mel1a or MTNR1A) and MT2 (also known as Mel1b or MTNR1B).

MT1 receptor, specifically, is a gene that encodes for the MT1 melatonin receptor protein. This receptor is primarily expressed in the suprachiasmatic nucleus (SCN) of the hypothalamus, which is the body's central circadian pacemaker, as well as in various other tissues such as the retina, pineal gland, and peripheral blood vessels. The activation of MT1 receptors by melatonin can lead to a variety of downstream effects, including the regulation of sleep onset and duration, circadian rhythm entrainment, and the modulation of mood and cognitive function. Additionally, MT1 receptors have been implicated in the regulation of several other physiological processes such as blood pressure, body temperature, and immune function.

Benzoic acid is an organic compound with the formula C6H5COOH. It is a colorless crystalline solid that is slightly soluble in water and more soluble in organic solvents. Benzoic acid occurs naturally in various plants and serves as an intermediate in the synthesis of other chemical compounds.

In medical terms, benzoic acid and its salts (sodium benzoate, potassium benzoate) are used as preservatives in food, beverages, and cosmetics to prevent bacterial growth. They work by inhibiting the growth of bacteria, particularly gram-positive bacteria, through the disruption of their energy production processes.

Additionally, sodium benzoate is sometimes used as a treatment for hyperammonemia, a condition characterized by high levels of ammonia in the blood. In this case, sodium benzoate acts as a detoxifying agent by binding to excess ammonia and converting it into a more easily excreted compound called hippuric acid.

It is important to note that benzoic acid and its salts can cause allergic reactions or skin irritation in some individuals, particularly those with pre-existing sensitivities or conditions. As with any medication or chemical substance, it should be used under the guidance of a healthcare professional.

"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.

Nitric oxide (NO) is a molecule made up of one nitrogen atom and one oxygen atom. In the body, it is a crucial signaling molecule involved in various physiological processes such as vasodilation, immune response, neurotransmission, and inhibition of platelet aggregation. It is produced naturally by the enzyme nitric oxide synthase (NOS) from the amino acid L-arginine. Inhaled nitric oxide is used medically to treat pulmonary hypertension in newborns and adults, as it helps to relax and widen blood vessels, improving oxygenation and blood flow.

A melatonin receptor is a type of G protein-coupled receptor (GPCR) that binds to the hormone melatonin, which is primarily involved in regulating sleep-wake cycles. There are two main subtypes of melatonin receptors, MT1 and MT2, which are encoded by the genes MTNR1A and MTNR1B, respectively.

MT2 receptor, also known as Mel1b or MTNR1B, is a subtype of melatonin receptor that is widely expressed in various tissues, including the retina, brain, heart, and gastrointestinal tract. MT2 receptors are involved in several physiological functions, such as circadian rhythm regulation, sleep onset and duration, and neuroprotection.

MT2 receptor activation has been shown to promote sleep onset and consolidation, reduce anxiety and depressive-like behaviors, and improve cognitive function. Additionally, MT2 receptors have been implicated in the regulation of glucose metabolism, insulin secretion, and energy homeostasis, suggesting a potential role in the treatment of metabolic disorders such as diabetes.

Overall, melatonin receptors, particularly the MT2 subtype, are important targets for developing therapies for sleep disorders, neuropsychiatric conditions, and metabolic diseases.

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).

Copper is a chemical element with the symbol Cu (from Latin: *cuprum*) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. Copper is found as a free element in nature, and it is also a constituent of many minerals such as chalcopyrite and bornite.

In the human body, copper is an essential trace element that plays a role in various physiological processes, including iron metabolism, energy production, antioxidant defense, and connective tissue synthesis. Copper is found in a variety of foods, such as shellfish, nuts, seeds, whole grains, and organ meats. The recommended daily intake of copper for adults is 900 micrograms (mcg) per day.

Copper deficiency can lead to anemia, neutropenia, impaired immune function, and abnormal bone development. Copper toxicity, on the other hand, can cause nausea, vomiting, abdominal pain, diarrhea, and in severe cases, liver damage and neurological symptoms. Therefore, it is important to maintain a balanced copper intake through diet and supplements if necessary.

Glutathione peroxidase (GPx) is a family of enzymes with peroxidase activity whose main function is to protect the organism from oxidative damage. They catalyze the reduction of hydrogen peroxide, lipid peroxides, and organic hydroperoxides to water or corresponding alcohols, using glutathione (GSH) as a reducing agent, which is converted to its oxidized form (GSSG). There are several isoforms of GPx found in different tissues, including GPx1 (also known as cellular GPx), GPx2 (gastrointestinal GPx), GPx3 (plasma GPx), GPx4 (also known as phospholipid hydroperoxide GPx), and GPx5-GPx8. These enzymes play crucial roles in various biological processes, such as antioxidant defense, cell signaling, and apoptosis regulation.

Dimethyl Sulfoxide (DMSO) is an organosulfur compound with the formula (CH3)2SO. It is a polar aprotic solvent, which means it can dissolve both polar and nonpolar compounds. DMSO has a wide range of uses in industry and in laboratory research, including as a cryoprotectant, a solvent for pharmaceuticals, and a penetration enhancer in topical formulations.

In medicine, DMSO is used as a topical analgesic and anti-inflammatory agent. It works by increasing the flow of blood and other fluids to the site of application, which can help to reduce pain and inflammation. DMSO is also believed to have antioxidant properties, which may contribute to its therapeutic effects.

It's important to note that while DMSO has been studied for various medical uses, its effectiveness for many conditions is not well established, and it can have side effects, including skin irritation and a garlic-like taste or odor in the mouth after application. It should be used under the supervision of a healthcare provider.

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.

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.

Spin trapping is a technique used in free radical research to detect and study short-lived, reactive free radicals. It involves the use of spin trap compounds, which react with the radicals to form more stable, longer-lived radical adducts. These adducts can then be detected and analyzed using various techniques such as electron paramagnetic resonance (EPR) spectroscopy.

The spin trap compound is typically a nitrone or nitroso compound, which reacts with the free radical to form a nitroxide radical. The nitroxide radical has a characteristic EPR spectrum that can be used to identify and quantify the original free radical. This technique allows for the direct detection and measurement of free radicals in biological systems, providing valuable insights into their role in various physiological and pathological processes.

Phenols, also known as phenolic acids or phenol derivatives, are a class of chemical compounds consisting of a hydroxyl group (-OH) attached to an aromatic hydrocarbon ring. In the context of medicine and biology, phenols are often referred to as a type of antioxidant that can be found in various foods and plants.

Phenols have the ability to neutralize free radicals, which are unstable molecules that can cause damage to cells and contribute to the development of chronic diseases such as cancer, heart disease, and neurodegenerative disorders. Some common examples of phenolic compounds include gallic acid, caffeic acid, ferulic acid, and ellagic acid, among many others.

Phenols can also have various pharmacological activities, including anti-inflammatory, antimicrobial, and analgesic effects. However, some phenolic compounds can also be toxic or irritating to the body in high concentrations, so their use as therapeutic agents must be carefully monitored and controlled.

Mannitol is a type of sugar alcohol (a sugar substitute) used primarily as a diuretic to reduce brain swelling caused by traumatic brain injury or other causes that induce increased pressure in the brain. It works by drawing water out of the body through the urine. It's also used before surgeries in the heart, lungs, and kidneys to prevent fluid buildup.

In addition, mannitol is used in medical laboratories as a medium for growing bacteria and other microorganisms, and in some types of chemical research. In the clinic, it is also used as an osmotic agent in eye drops to reduce the pressure inside the eye in conditions such as glaucoma.

It's important to note that mannitol should be used with caution in patients with heart or kidney disease, as well as those who are dehydrated, because it can lead to electrolyte imbalances and other complications.

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.

DNA damage refers to any alteration in the structure or composition of deoxyribonucleic acid (DNA), which is the genetic material present in cells. DNA damage can result from various internal and external factors, including environmental exposures such as ultraviolet radiation, tobacco smoke, and certain chemicals, as well as normal cellular processes such as replication and oxidative metabolism.

Examples of DNA damage include base modifications, base deletions or insertions, single-strand breaks, double-strand breaks, and crosslinks between the two strands of the DNA helix. These types of damage can lead to mutations, genomic instability, and chromosomal aberrations, which can contribute to the development of diseases such as cancer, neurodegenerative disorders, and aging-related conditions.

The body has several mechanisms for repairing DNA damage, including base excision repair, nucleotide excision repair, mismatch repair, and double-strand break repair. However, if the damage is too extensive or the repair mechanisms are impaired, the cell may undergo apoptosis (programmed cell death) to prevent the propagation of potentially harmful mutations.

Lipoprotein receptors are specialized proteins found on the surface of cells that play a crucial role in the metabolism of lipoproteins, which are complex particles composed of lipids and proteins. These receptors bind to specific lipoproteins in the bloodstream, facilitating their uptake into the cell for further processing.

There are several types of lipoprotein receptors, including:

1. LDL (Low-Density Lipoprotein) Receptor: This receptor is responsible for recognizing and internalizing LDL particles, which are rich in cholesterol. Once inside the cell, LDL particles release their cholesterol, which can then be used for various cellular functions or stored for later use. Defects in the LDL receptor can lead to elevated levels of LDL cholesterol in the blood and an increased risk of developing cardiovascular disease.
2. HDL (High-Density Lipoprotein) Receptor: This receptor is involved in the clearance of HDL particles from the bloodstream. HDL particles are responsible for transporting excess cholesterol from peripheral tissues to the liver, where it can be processed and eliminated from the body.
3. VLDL (Very Low-Density Lipoprotein) Receptor: This receptor recognizes and internalizes VLDL particles, which are produced by the liver and carry triglycerides and cholesterol to peripheral tissues. VLDL particles are subsequently converted into LDL particles in the bloodstream.
4. LRP (Low-Density Lipoprotein Receptor-Related Protein) Family: This family of receptors includes several members, such as LRP1 and LRP2, that play roles in various cellular processes, including lipid metabolism, protein trafficking, and cell signaling. They can bind to a variety of ligands, including lipoproteins, proteases, and extracellular matrix components.

In summary, lipoprotein receptors are essential for maintaining proper lipid metabolism and homeostasis by facilitating the uptake, processing, and elimination of lipoproteins in the body.

Hydroxy acids are a class of chemical compounds that contain both a carboxylic acid group and a hydroxyl group. They are commonly used in dermatology and cosmetic products for their exfoliating, moisturizing, and anti-aging properties. The two main types of hydroxy acids used in skincare are alpha-hydroxy acids (AHAs) and beta-hydroxy acids (BHAs).

Alpha-hydroxy acids include compounds such as glycolic acid, lactic acid, malic acid, tartaric acid, and citric acid. They work by breaking down the "glue" that holds dead skin cells together, promoting cell turnover and helping to improve the texture and tone of the skin. AHAs are also known for their ability to improve the appearance of fine lines, wrinkles, and age spots.

Beta-hydroxy acids, on the other hand, are primarily represented by salicylic acid. BHAs are oil-soluble, which allows them to penetrate deeper into the pores and exfoliate dead skin cells and excess sebum that can lead to clogged pores and acne breakouts.

It is important to note that hydroxy acids can cause skin irritation and sensitivity to sunlight, so it is recommended to use sunscreen and start with lower concentrations when first incorporating them into a skincare routine.

Decanoic acids are a type of medium-chain fatty acid with a chain length of 10 carbon atoms. The most common decanoic acid is decanoic acid or capric acid. It is found in various animal and plant sources, such as coconut oil and cow's milk. Decanoic acids have a variety of uses, including as ingredients in cosmetics and food products, and as a potential treatment for medical conditions such as epilepsy and bacterial infections. In the body, decanoic acids are metabolized in the liver and used for energy production.

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.

Myocardial reperfusion injury is a pathological process that occurs when blood flow is restored to the heart muscle (myocardium) after a period of ischemia or reduced oxygen supply, such as during a myocardial infarction (heart attack). The restoration of blood flow, although necessary to salvage the dying tissue, can itself cause further damage to the heart muscle. This paradoxical phenomenon is known as myocardial reperfusion injury.

The mechanisms behind myocardial reperfusion injury are complex and involve several processes, including:

1. Oxidative stress: The sudden influx of oxygen into the previously ischemic tissue leads to an overproduction of reactive oxygen species (ROS), which can damage cellular structures, such as proteins, lipids, and DNA.
2. Calcium overload: During reperfusion, there is an increase in calcium influx into the cardiomyocytes (heart muscle cells). This elevated intracellular calcium level can disrupt normal cellular functions, leading to further damage.
3. Inflammation: Reperfusion triggers an immune response, with the recruitment of inflammatory cells, such as neutrophils and monocytes, to the site of injury. These cells release cytokines and other mediators that can exacerbate tissue damage.
4. Mitochondrial dysfunction: The restoration of blood flow can cause mitochondria, the powerhouses of the cell, to malfunction, leading to the release of pro-apoptotic factors and contributing to cell death.
5. Vasoconstriction and microvascular obstruction: During reperfusion, there may be vasoconstriction of the small blood vessels (microvasculature) in the heart, which can further limit blood flow and contribute to tissue damage.

Myocardial reperfusion injury is a significant concern because it can negate some of the benefits of early reperfusion therapy, such as thrombolysis or primary percutaneous coronary intervention (PCI), used to treat acute myocardial infarction. Strategies to minimize myocardial reperfusion injury are an area of active research and include pharmacological interventions, ischemic preconditioning, and remote ischemic conditioning.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

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

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

Examples of animal disease models include:

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

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

Molecular structure, in the context of biochemistry and molecular biology, refers to the arrangement and organization of atoms and chemical bonds within a molecule. It describes the three-dimensional layout of the constituent elements, including their spatial relationships, bond lengths, and angles. Understanding molecular structure is crucial for elucidating the functions and reactivities of biological macromolecules such as proteins, nucleic acids, lipids, and carbohydrates. Various experimental techniques, like X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cryo-electron microscopy (cryo-EM), are employed to determine molecular structures at atomic resolution, providing valuable insights into their biological roles and potential therapeutic targets.

Brain ischemia is the medical term used to describe a reduction or interruption of blood flow to the brain, leading to a lack of oxygen and glucose delivery to brain tissue. This can result in brain damage or death of brain cells, known as infarction. Brain ischemia can be caused by various conditions such as thrombosis (blood clot formation), embolism (obstruction of a blood vessel by a foreign material), or hypoperfusion (reduced blood flow). The severity and duration of the ischemia determine the extent of brain damage. Symptoms can range from mild, such as transient ischemic attacks (TIAs or "mini-strokes"), to severe, including paralysis, speech difficulties, loss of consciousness, and even death. Immediate medical attention is required for proper diagnosis and treatment to prevent further damage and potential long-term complications.

Peroxides, in a medical context, most commonly refer to chemical compounds that contain the peroxide ion (O2−2). Peroxides are characterized by the presence of an oxygen-oxygen single bond and can be found in various substances.

In dentistry, hydrogen peroxide (H2O2) is a widely used agent for teeth whitening or bleaching due to its oxidizing properties. It can help remove stains and discoloration on the tooth surface by breaking down into water and oxygen-free radicals, which react with the stain molecules, ultimately leading to their oxidation and elimination.

However, it is essential to note that high concentrations of hydrogen peroxide or prolonged exposure can cause tooth sensitivity, irritation to the oral soft tissues, and potential damage to the dental pulp. Therefore, professional supervision and appropriate concentration control are crucial when using peroxides for dental treatments.

Deoxyribose is a type of sugar that makes up the structural backbone of DNA (deoxyribonucleic acid), one of the two main types of nucleic acids in cells. The chemical formula for deoxyribose is C5H10O4, and it has a five-carbon ring structure with four hydroxyl (-OH) groups and one hydrogen atom attached to the carbons.

The key difference between deoxyribose and ribose, which makes up the structural backbone of RNA (ribonucleic acid), is that deoxyribose lacks a hydroxyl group on the second carbon atom in its ring structure. This small difference has significant implications for the structure and function of DNA compared to RNA.

Deoxyribose plays an essential role in the replication, transcription, and repair of genetic material in cells. It forms the sugar-phosphate backbone of DNA by linking with phosphate groups through ester bonds between the 3' carbon atom of one deoxyribose molecule and the 5' carbon atom of another, creating a long, twisted ladder-like structure known as a double helix. The nitrogenous bases adenine, thymine, guanine, and cytosine attach to the 1' carbon atom of each deoxyribose molecule in the DNA strand, forming pairs that are complementary to each other (adenine with thymine and guanine with cytosine).

Overall, deoxyribose is a crucial component of DNA, enabling the storage and transmission of genetic information from one generation to the next.

NADPH oxidase is an enzyme complex that plays a crucial role in the production of reactive oxygen species (ROS) in various cell types. The primary function of NADPH oxidase is to catalyze the transfer of electrons from NADPH to molecular oxygen, resulting in the formation of superoxide radicals. This enzyme complex consists of several subunits, including two membrane-bound components (gp91phox and p22phox) and several cytosolic components (p47phox, p67phox, p40phox, and rac1 or rac2). Upon activation, these subunits assemble to form a functional enzyme complex that generates ROS, which serve as important signaling molecules in various cellular processes. However, excessive or uncontrolled production of ROS by NADPH oxidase has been implicated in the pathogenesis of several diseases, such as cardiovascular disorders, neurodegenerative diseases, and cancer.

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.

Scavenger receptors, class F (SR-F), are a subclass of scavenger receptors that play a crucial role in the recognition and clearance of modified low-density lipoproteins (LDL) and other waste products in the body. These receptors are expressed mainly on the surface of macrophages, dendritic cells, and endothelial cells.

SR-F consists of two members: SR-FI and SR-FII. Both receptors contain multiple domains, including extracellular cysteine-rich domains, transmembrane regions, and intracellular signaling domains. These features enable them to bind various ligands, such as oxidized LDL, acetylated LDL, advanced glycation end products (AGEs), and apoptotic cells.

SR-F receptors have been implicated in several physiological processes, including lipid metabolism, immune response, inflammation, and atherosclerosis. Dysregulation of these receptors has been associated with the development of various diseases, such as cardiovascular disease, diabetes, and neurodegenerative disorders.

In summary, scavenger receptors, class F, are essential for maintaining homeostasis by recognizing and removing waste products in the body. Their dysfunction can contribute to several pathological conditions, making them an important area of research in biology and medicine.

Anserine is a type of protein that belongs to the family of muscle proteins called myofibrillar proteins. It is found in high concentrations in the muscles of birds, especially in the breast muscle, and is also present in the muscles of some mammals, including humans. Anserine is composed of three peptide chains: two actin molecules and one tropomyosin molecule. It plays a role in the contraction and relaxation of muscles, and has been studied for its potential role in muscle function and disease. In humans, anserine is found primarily in type II (fast-twitch) muscle fibers, which are responsible for powerful, quick movements.

CD36 is a type of protein found on the surface of certain cells in the human body, including platelets, white blood cells (monocytes and macrophages), and fat (adipose) cells. It is a type of scavenger receptor that plays a role in various biological processes, such as:

1. Fatty acid uptake and metabolism: CD36 helps facilitate the transport of long-chain fatty acids into cells for energy production and storage.
2. Inflammation and immune response: CD36 is involved in the recognition and clearance of foreign substances (pathogens) and damaged or dying cells, which can trigger an immune response.
3. Angiogenesis: CD36 has been implicated in the regulation of blood vessel formation (angiogenesis), particularly during wound healing and tumor growth.
4. Atherosclerosis: CD36 has been associated with the development and progression of atherosclerosis, a condition characterized by the buildup of fats, cholesterol, and other substances in and on the artery walls. This is due to its role in the uptake of oxidized low-density lipoprotein (oxLDL) by macrophages, leading to the formation of foam cells and the development of fatty streaks in the arterial wall.
5. Infectious diseases: CD36 has been identified as a receptor for various pathogens, including malaria parasites, HIV, and some bacteria, which can use this protein to gain entry into host cells.

As an antigen, CD36 is a molecule that can be targeted by the immune system to produce an immune response. Antibodies against CD36 have been found in various diseases, such as autoimmune disorders and certain infections. Modulation of CD36 activity has been suggested as a potential therapeutic strategy for several conditions, including atherosclerosis, diabetes, and infectious diseases.

Thiobarbituric acid reactive substances (TBARS) is not a medical term per se, but rather a method used to measure lipid peroxidation in biological samples. Lipid peroxidation is a process by which free radicals steal electrons from lipids, leading to cellular damage and potential disease progression.

The TBARS assay measures the amount of malondialdehyde (MDA), a byproduct of lipid peroxidation, that reacts with thiobarbituric acid (TBA) to produce a pink-colored complex. The concentration of this complex is then measured and used as an indicator of lipid peroxidation in the sample.

While TBARS has been widely used as a measure of oxidative stress, it has limitations, including potential interference from other compounds that can react with TBA and produce similar-colored complexes. Therefore, more specific and sensitive methods for measuring lipid peroxidation have since been developed.

Flavonoids are a type of plant compounds with antioxidant properties that are beneficial to health. They are found in various fruits, vegetables, grains, and wine. Flavonoids have been studied for their potential to prevent chronic diseases such as heart disease and cancer due to their ability to reduce inflammation and oxidative stress.

There are several subclasses of flavonoids, including:

1. Flavanols: Found in tea, chocolate, grapes, and berries. They have been shown to improve blood flow and lower blood pressure.
2. Flavones: Found in parsley, celery, and citrus fruits. They have anti-inflammatory and antioxidant properties.
3. Flavanonols: Found in citrus fruits, onions, and tea. They have been shown to improve blood flow and reduce inflammation.
4. Isoflavones: Found in soybeans and legumes. They have estrogen-like effects and may help prevent hormone-related cancers.
5. Anthocyanidins: Found in berries, grapes, and other fruits. They have antioxidant properties and may help improve vision and memory.

It is important to note that while flavonoids have potential health benefits, they should not be used as a substitute for medical treatment or a healthy lifestyle. It is always best to consult with a healthcare professional before starting any new supplement regimen.

In the context of medicine, iron is an essential micromineral and key component of various proteins and enzymes. It plays a crucial role in oxygen transport, DNA synthesis, and energy production within the body. Iron exists in two main forms: heme and non-heme. Heme iron is derived from hemoglobin and myoglobin in animal products, while non-heme iron comes from plant sources and supplements.

The recommended daily allowance (RDA) for iron varies depending on age, sex, and life stage:

* For men aged 19-50 years, the RDA is 8 mg/day
* For women aged 19-50 years, the RDA is 18 mg/day
* During pregnancy, the RDA increases to 27 mg/day
* During lactation, the RDA for breastfeeding mothers is 9 mg/day

Iron deficiency can lead to anemia, characterized by fatigue, weakness, and shortness of breath. Excessive iron intake may result in iron overload, causing damage to organs such as the liver and heart. Balanced iron levels are essential for maintaining optimal health.

Carnosine is a dipeptide molecule composed of the amino acids histidine and alanine, which is naturally found in high concentrations in certain tissues of the body, particularly in muscle and brain tissue. It acts as an antioxidant, helping to protect cells from damage caused by free radicals and other oxidative stressors. Carnosine also has anti-glycation properties, meaning it helps prevent the formation of advanced glycation end products (AGEs) that can contribute to aging and age-related diseases. Additionally, carnosine has been shown to have potential benefits in neuroprotection, cardioprotection, and anti-inflammation. It is being studied for its potential therapeutic uses in various health conditions, including diabetes, cataracts, Alzheimer's disease, and other neurological disorders.

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.

Brain edema is a medical condition characterized by the abnormal accumulation of fluid in the brain, leading to an increase in intracranial pressure. This can result from various causes, such as traumatic brain injury, stroke, infection, brain tumors, or inflammation. The swelling of the brain can compress vital structures, impair blood flow, and cause neurological symptoms, which may range from mild headaches to severe cognitive impairment, seizures, coma, or even death if not treated promptly and effectively.

Nitric Oxide Synthase (NOS) is a group of enzymes that catalyze the production of nitric oxide (NO) from L-arginine. There are three distinct isoforms of NOS, each with different expression patterns and functions:

1. Neuronal Nitric Oxide Synthase (nNOS or NOS1): This isoform is primarily expressed in the nervous system and plays a role in neurotransmission, synaptic plasticity, and learning and memory processes.
2. Inducible Nitric Oxide Synthase (iNOS or NOS2): This isoform is induced by various stimuli such as cytokines, lipopolysaccharides, and hypoxia in a variety of cells including immune cells, endothelial cells, and smooth muscle cells. iNOS produces large amounts of NO, which functions as a potent effector molecule in the immune response, particularly in the defense against microbial pathogens.
3. Endothelial Nitric Oxide Synthase (eNOS or NOS3): This isoform is constitutively expressed in endothelial cells and produces low levels of NO that play a crucial role in maintaining vascular homeostasis by regulating vasodilation, inhibiting platelet aggregation, and preventing smooth muscle cell proliferation.

Overall, NOS plays an essential role in various physiological processes, including neurotransmission, immune response, cardiovascular function, and respiratory regulation. Dysregulation of NOS activity has been implicated in several pathological conditions such as hypertension, atherosclerosis, neurodegenerative diseases, and inflammatory disorders.

The brain is the central organ of the nervous system, responsible for receiving and processing sensory information, regulating vital functions, and controlling behavior, movement, and cognition. It is divided into several distinct regions, each with specific functions:

1. Cerebrum: The largest part of the brain, responsible for higher cognitive functions such as thinking, learning, memory, language, and perception. It is divided into two hemispheres, each controlling the opposite side of the body.
2. Cerebellum: Located at the back of the brain, it is responsible for coordinating muscle movements, maintaining balance, and fine-tuning motor skills.
3. Brainstem: Connects the cerebrum and cerebellum to the spinal cord, controlling vital functions such as breathing, heart rate, and blood pressure. It also serves as a relay center for sensory information and motor commands between the brain and the rest of the body.
4. Diencephalon: A region that includes the thalamus (a major sensory relay station) and hypothalamus (regulates hormones, temperature, hunger, thirst, and sleep).
5. Limbic system: A group of structures involved in emotional processing, memory formation, and motivation, including the hippocampus, amygdala, and cingulate gyrus.

The brain is composed of billions of interconnected neurons that communicate through electrical and chemical signals. It is protected by the skull and surrounded by three layers of membranes called meninges, as well as cerebrospinal fluid that provides cushioning and nutrients.

The endothelium is a thin layer of simple squamous epithelial cells that lines the interior surface of blood vessels, lymphatic vessels, and heart chambers. The vascular endothelium, specifically, refers to the endothelial cells that line the blood vessels. These cells play a crucial role in maintaining vascular homeostasis by regulating vasomotor tone, coagulation, platelet activation, inflammation, and permeability of the vessel wall. They also contribute to the growth and repair of the vascular system and are involved in various pathological processes such as atherosclerosis, hypertension, and diabetes.

Xanthine is a purine base, which is a naturally occurring heterocyclic aromatic organic compound. It is formed in the body during the metabolism of purines, and it's a normal intermediate in the breakdown of nucleotides to uric acid. Xanthine is also found in various foods and beverages, such as coffee, tea, and chocolate. In the medical field, xanthine may refer to a class of drugs called xanthine derivatives, which include theophylline and caffeine, that act as bronchodilators and cardiac stimulants.

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.

Cell hypoxia, also known as cellular hypoxia or tissue hypoxia, refers to a condition in which the cells or tissues in the body do not receive an adequate supply of oxygen. Oxygen is essential for the production of energy in the form of ATP (adenosine triphosphate) through a process called oxidative phosphorylation. When the cells are deprived of oxygen, they switch to anaerobic metabolism, which produces lactic acid as a byproduct and can lead to acidosis.

Cell hypoxia can result from various conditions, including:

1. Low oxygen levels in the blood (hypoxemia) due to lung diseases such as chronic obstructive pulmonary disease (COPD), pneumonia, or high altitude.
2. Reduced blood flow to tissues due to cardiovascular diseases such as heart failure, peripheral artery disease, or shock.
3. Anemia, which reduces the oxygen-carrying capacity of the blood.
4. Carbon monoxide poisoning, which binds to hemoglobin and prevents it from carrying oxygen.
5. Inadequate ventilation due to trauma, drug overdose, or other causes that can lead to respiratory failure.

Cell hypoxia can cause cell damage, tissue injury, and organ dysfunction, leading to various clinical manifestations depending on the severity and duration of hypoxia. Treatment aims to correct the underlying cause and improve oxygen delivery to the tissues.

The myocardium is the middle layer of the heart wall, composed of specialized cardiac muscle cells that are responsible for pumping blood throughout the body. It forms the thickest part of the heart wall and is divided into two sections: the left ventricle, which pumps oxygenated blood to the rest of the body, and the right ventricle, which pumps deoxygenated blood to the lungs.

The myocardium contains several types of cells, including cardiac muscle fibers, connective tissue, nerves, and blood vessels. The muscle fibers are arranged in a highly organized pattern that allows them to contract in a coordinated manner, generating the force necessary to pump blood through the heart and circulatory system.

Damage to the myocardium can occur due to various factors such as ischemia (reduced blood flow), infection, inflammation, or genetic disorders. This damage can lead to several cardiac conditions, including heart failure, arrhythmias, and cardiomyopathy.

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

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

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

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

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

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

Iron chelating agents are medications that bind to iron in the body, forming a stable complex that can then be excreted from the body. These agents are primarily used to treat iron overload, a condition that can occur due to frequent blood transfusions or certain genetic disorders such as hemochromatosis. By reducing the amount of iron in the body, these medications can help prevent or reduce damage to organs such as the heart and liver. Examples of iron chelating agents include deferoxamine, deferasirox, and deferiprone.

The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:

1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.

Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.

"Inbred strains of rats" are genetically identical rodents that have been produced through many generations of brother-sister mating. This results in a high degree of homozygosity, where the genes at any particular locus in the genome are identical in all members of the strain.

Inbred strains of rats are widely used in biomedical research because they provide a consistent and reproducible genetic background for studying various biological phenomena, including the effects of drugs, environmental factors, and genetic mutations on health and disease. Additionally, inbred strains can be used to create genetically modified models of human diseases by introducing specific mutations into their genomes.

Some commonly used inbred strains of rats include the Wistar Kyoto (WKY), Sprague-Dawley (SD), and Fischer 344 (F344) rat strains. Each strain has its own unique genetic characteristics, making them suitable for different types of research.

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

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

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

Hypochlorous acid (HClO) is a weak acid that is primarily used as a disinfectant and sanitizer. It is a colorless and nearly odorless substance that is formed when chlorine gas is dissolved in water. Hypochlorous acid is a powerful oxidizing agent, which makes it effective at killing bacteria, viruses, and other microorganisms.

In the human body, hypochlorous acid is produced by white blood cells as part of the immune response to infection. It helps to kill invading pathogens and prevent the spread of infection. Hypochlorous acid is also used in medical settings as a disinfectant for surfaces and equipment, as well as in wound care to help prevent infection and promote healing.

It's important to note that while hypochlorous acid is safe and effective as a disinfectant, it can be harmful if swallowed or inhaled in large quantities. Therefore, it should be used with caution and according to the manufacturer's instructions.

Chelating agents are substances that can bind and form stable complexes with certain metal ions, preventing them from participating in chemical reactions. In medicine, chelating agents are used to remove toxic or excessive amounts of metal ions from the body. For example, ethylenediaminetetraacetic acid (EDTA) is a commonly used chelating agent that can bind with heavy metals such as lead and mercury, helping to eliminate them from the body and reduce their toxic effects. Other chelating agents include dimercaprol (BAL), penicillamine, and deferoxamine. These agents are used to treat metal poisoning, including lead poisoning, iron overload, and copper toxicity.

Methylurea compounds are organic substances that contain the functional group methylurea, which is formed by the reaction between methylamine and carbonyl diurea. These compounds have the general structure O=C(NH)NH-CO-N(CH3)NH2. They can be found in various chemical and pharmaceutical products, including as intermediates in the synthesis of certain drugs and polymers. Methylurea compounds are also used as herbicides and in the treatment of some medical conditions. However, exposure to high levels of methylurea or its derivatives can be harmful and may cause irritation to the skin, eyes, and respiratory tract.

Drug synergism is a pharmacological concept that refers to the interaction between two or more drugs, where the combined effect of the drugs is greater than the sum of their individual effects. This means that when these drugs are administered together, they produce an enhanced therapeutic response compared to when they are given separately.

Drug synergism can occur through various mechanisms, such as:

1. Pharmacodynamic synergism - When two or more drugs interact with the same target site in the body and enhance each other's effects.
2. Pharmacokinetic synergism - When one drug affects the metabolism, absorption, distribution, or excretion of another drug, leading to an increased concentration of the second drug in the body and enhanced therapeutic effect.
3. Physiochemical synergism - When two drugs interact physically, such as when one drug enhances the solubility or permeability of another drug, leading to improved absorption and bioavailability.

It is important to note that while drug synergism can result in enhanced therapeutic effects, it can also increase the risk of adverse reactions and toxicity. Therefore, healthcare providers must carefully consider the potential benefits and risks when prescribing combinations of drugs with known or potential synergistic effects.

Immunologic receptors are specialized proteins found on the surface of immune cells that recognize and bind to specific molecules, known as antigens, on the surface of pathogens or infected cells. This binding triggers a series of intracellular signaling events that activate the immune cell and initiate an immune response.

There are several types of immunologic receptors, including:

1. T-cell receptors (TCRs): These receptors are found on the surface of T cells and recognize antigens presented in the context of major histocompatibility complex (MHC) molecules.
2. B-cell receptors (BCRs): These receptors are found on the surface of B cells and recognize free antigens in solution.
3. Pattern recognition receptors (PRRs): These receptors are found inside immune cells and recognize conserved molecular patterns associated with pathogens, such as lipopolysaccharides and flagellin.
4. Fc receptors: These receptors are found on the surface of various immune cells and bind to the constant region of antibodies, mediating effector functions such as phagocytosis and antibody-dependent cellular cytotoxicity (ADCC).

Immunologic receptors play a critical role in the recognition and elimination of pathogens and infected cells, and dysregulation of these receptors can lead to immune disorders and diseases.

Ferrous compounds are inorganic substances that contain iron (Fe) in its +2 oxidation state. The term "ferrous" is derived from the Latin word "ferrum," which means iron. Ferrous compounds are often used in medicine, particularly in the treatment of iron-deficiency anemia due to their ability to provide bioavailable iron to the body.

Examples of ferrous compounds include ferrous sulfate, ferrous gluconate, and ferrous fumarate. These compounds are commonly found in dietary supplements and multivitamins. Ferrous sulfate is one of the most commonly used forms of iron supplementation, as it has a high iron content and is relatively inexpensive.

It's important to note that ferrous compounds can be toxic in large doses, so they should be taken under the guidance of a healthcare professional. Overdose can lead to symptoms such as nausea, vomiting, diarrhea, abdominal pain, and potentially fatal consequences if left untreated.

Benzoates are the salts and esters of benzoic acid. They are widely used as preservatives in foods, cosmetics, and pharmaceuticals to prevent the growth of microorganisms. The chemical formula for benzoic acid is C6H5COOH, and when it is combined with a base (like sodium or potassium), it forms a benzoate salt (e.g., sodium benzoate or potassium benzoate). When benzoic acid reacts with an alcohol, it forms a benzoate ester (e.g., methyl benzoate or ethyl benzoate).

Benzoates are generally considered safe for use in food and cosmetics in small quantities. However, some people may have allergies or sensitivities to benzoates, which can cause reactions such as hives, itching, or asthma symptoms. In addition, there is ongoing research into the potential health effects of consuming high levels of benzoates over time, particularly in relation to gut health and the development of certain diseases.

In a medical context, benzoates may also be used as a treatment for certain conditions. For example, sodium benzoate is sometimes given to people with elevated levels of ammonia in their blood (hyperammonemia) to help reduce those levels and prevent brain damage. This is because benzoates can bind with excess ammonia in the body and convert it into a form that can be excreted in urine.

Butylated Hydroxytoluene (BHT) is a synthetic organic compound that is commonly used as a food additive and preservative. Its chemical formula is C15H24O. BHT is an antioxidant, which means it helps to prevent the oxidation of fats and oils, thereby extending the shelf life of foods and cosmetics.

In medical terms, BHT is sometimes used as a preservative in pharmaceuticals and medical devices. It has been shown to have some antimicrobial properties, which can help to prevent the growth of bacteria, fungi, and other microorganisms. However, its use in medical applications is relatively limited compared to its widespread use in food and cosmetic products.

It's worth noting that while BHT is generally recognized as safe by regulatory agencies such as the U.S. Food and Drug Administration (FDA), some studies have suggested that it may have potential health risks, including liver toxicity and possible carcinogenic effects. Therefore, its use in food and other products is subject to certain limits and regulations.

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.

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

Low-density lipoproteins (LDL), also known as "bad cholesterol," are a type of lipoprotein that carry cholesterol and other fats from the liver to cells throughout the body. High levels of LDL in the blood can lead to the buildup of cholesterol in the walls of the arteries, which can increase the risk of heart disease and stroke.

Lipoproteins are complex particles composed of proteins (apolipoproteins) and lipids (cholesterol, triglycerides, and phospholipids) that are responsible for transporting fat molecules around the body in the bloodstream. LDL is one type of lipoprotein, along with high-density lipoproteins (HDL), very low-density lipoproteins (VLDL), and chylomicrons.

LDL particles are smaller than HDL particles and can easily penetrate the artery walls, leading to the formation of plaques that can narrow or block the arteries. Therefore, maintaining healthy levels of LDL in the blood is essential for preventing cardiovascular disease.

Peroxynitrous acid (ONOOH) is a highly reactive nitrogen species formed from the reaction between nitric oxide (NO) and superoxide radical (O2-). It is an unstable compound that quickly decomposes to form other reactive species, such as nitrogen dioxide (NO2) and hydroxyl radical (HO•), which can cause significant damage to biological molecules, including proteins, lipids, and DNA. Peroxynitrous acid has been implicated in the pathogenesis of various diseases, including neurodegenerative disorders, cardiovascular disease, and cancer.

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

"Citrullus" is a genus of plants that includes watermelon and several other species of vine-like fruits. The name "Citrullus" comes from the Latin word for watermelon, "citrullus lanatus." Watermelons are the most well-known member of this genus and are popular for their juicy, sweet red or pink flesh, which is high in vitamins A and C and contains a high amount of lycopene. Other species in the Citrullus genus include citron melon (Citrullus lanatus var. citroides) and colocynth (Citrullus colocynthis), also known as bitter apple.

Benzothiazoles are a class of heterocyclic organic compounds that contain a benzene fused to a thiazole ring. They have the chemical formula C7H5NS. Benzothiazoles and their derivatives have a wide range of applications in various industries, including pharmaceuticals, agrochemicals, dyes, and materials science.

In the medical field, benzothiazoles have been studied for their potential therapeutic properties. Some benzothiazole derivatives have shown promising results as anti-inflammatory, antimicrobial, antiviral, and anticancer agents. However, more research is needed to fully understand the medical potential of these compounds and to develop safe and effective drugs based on them.

It's important to note that while benzothiazoles themselves have some biological activity, most of the medical applications come from their derivatives, which are modified versions of the basic benzothiazole structure. These modifications can significantly alter the properties of the compound, leading to new therapeutic possibilities.

Ferric compounds are inorganic compounds that contain the iron(III) cation, Fe3+. Iron(III) is a transition metal and can form stable compounds with various anions. Ferric compounds are often colored due to the d-d transitions of the iron ion. Examples of ferric compounds include ferric chloride (FeCl3), ferric sulfate (Fe2(SO4)3), and ferric oxide (Fe2O3). Ferric compounds have a variety of uses, including as catalysts, in dye production, and in medical applications.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

NF-κB (Nuclear Factor kappa-light-chain-enhancer of activated B cells) is a protein complex that plays a crucial role in regulating the immune response to infection and inflammation, as well as in cell survival, differentiation, and proliferation. It is composed of several subunits, including p50, p52, p65 (RelA), c-Rel, and RelB, which can form homodimers or heterodimers that bind to specific DNA sequences called κB sites in the promoter regions of target genes.

Under normal conditions, NF-κB is sequestered in the cytoplasm by inhibitory proteins known as IκBs (inhibitors of κB). However, upon stimulation by various signals such as cytokines, bacterial or viral products, and stress, IκBs are phosphorylated, ubiquitinated, and degraded, leading to the release and activation of NF-κB. Activated NF-κB then translocates to the nucleus, where it binds to κB sites and regulates the expression of target genes involved in inflammation, immunity, cell survival, and proliferation.

Dysregulation of NF-κB signaling has been implicated in various pathological conditions such as cancer, chronic inflammation, autoimmune diseases, and neurodegenerative disorders. Therefore, targeting NF-κB signaling has emerged as a potential therapeutic strategy for the treatment of these diseases.

Sulfhydryl compounds, also known as thiol compounds, are organic compounds that contain a functional group consisting of a sulfur atom bonded to a hydrogen atom (-SH). This functional group is also called a sulfhydryl group. Sulfhydryl compounds can be found in various biological systems and play important roles in maintaining the structure and function of proteins, enzymes, and other biomolecules. They can also act as antioxidants and help protect cells from damage caused by reactive oxygen species. Examples of sulfhydryl compounds include cysteine, glutathione, and coenzyme A.

Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).

The Western blotting procedure involves several steps:

1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.

Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.

Pregn-4-en-3-ones, or pregnatrienes, are a group of steroid hormones that contain a pregnane skeleton and three carbon-carbon double bonds. They are unsaturated steroids that have a structural backbone consisting of four fused rings, including three six-membered rings and one five-membered ring.

Pregnatrienes are important intermediates in the biosynthesis of various steroid hormones, such as progesterone, testosterone, and estrogens. They can be synthesized from cholesterol through a series of enzymatic reactions involving cytochrome P450 enzymes.

Pregn-4-en-3-one, also known as 5β-pregnan-3,20-dione or 5β-pregnadien-3,20-dione, is a specific example of a pregnatriene. It is a metabolic intermediate in the biosynthesis of progesterone and other steroid hormones.

It's important to note that while pregnatrienes are involved in various physiological processes, they are not typically used as medical terminology or diagnostic criteria. Instead, specific steroid hormones derived from pregnatrienes, such as progesterone or testosterone, are more commonly referenced in medical contexts.

Peroxidase is a type of enzyme that catalyzes the chemical reaction in which hydrogen peroxide (H2O2) is broken down into water (H2O) and oxygen (O2). This enzymatic reaction also involves the oxidation of various organic and inorganic compounds, which can serve as electron donors.

Peroxidases are widely distributed in nature and can be found in various organisms, including bacteria, fungi, plants, and animals. They play important roles in various biological processes, such as defense against oxidative stress, breakdown of toxic substances, and participation in metabolic pathways.

The peroxidase-catalyzed reaction can be represented by the following chemical equation:

H2O2 + 2e- + 2H+ → 2H2O

In this reaction, hydrogen peroxide is reduced to water, and the electron donor is oxidized. The peroxidase enzyme facilitates the transfer of electrons between the substrate (hydrogen peroxide) and the electron donor, making the reaction more efficient and specific.

Peroxidases have various applications in medicine, industry, and research. For example, they can be used for diagnostic purposes, as biosensors, and in the treatment of wastewater and medical wastes. Additionally, peroxidases are involved in several pathological conditions, such as inflammation, cancer, and neurodegenerative diseases, making them potential targets for therapeutic interventions.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Hydroxybenzoates are the salts or esters of hydroxybenzoic acids. They are commonly used as preservatives in food, cosmetics, and pharmaceutical products due to their antimicrobial and antifungal properties. The most common examples include methylparaben, ethylparaben, propylparaben, and butylparaben. These compounds work by inhibiting the growth of bacteria and fungi, thereby increasing the shelf life and safety of various products. However, there has been some concern about their potential health effects, including possible hormonal disruption, and their use in certain applications is being re-evaluated.

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.

Nitroblue Tetrazolium (NBT) is not a medical term per se, but a chemical compound that is widely used in scientific research and diagnostic tests. It's primarily used as an electron acceptor in various biochemical assays to detect the presence of certain enzymes or reactive oxygen species (ROS).

In a medical context, NBT is often used in the NBT reduction test, which is a diagnostic procedure to identify patients with chronic granulomatous disease (CGD), an inherited immunodeficiency disorder. In this test, white blood cells called phagocytes from the patient's blood sample are incubated with NBT and a stimulus that triggers their respiratory burst, such as bacterial particles. If the phagocytes can produce superoxide radicals during the respiratory burst, these radicals reduce NBT to form a blue-black insoluble formazan precipitate. In CGD patients, who have impaired production of ROS, there is no or significantly reduced formazan formation, indicating an abnormal NBT reduction test result.

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.

Nitrates are chemical compounds that consist of a nitrogen atom bonded to three oxygen atoms (NO3-). In the context of medical science, nitrates are often discussed in relation to their use as medications or their presence in food and water.

As medications, nitrates are commonly used to treat angina (chest pain) caused by coronary artery disease. Nitrates work by relaxing and widening blood vessels, which improves blood flow and reduces the workload on the heart. Some examples of nitrate medications include nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate.

In food and water, nitrates are naturally occurring compounds that can be found in a variety of vegetables, such as spinach, beets, and lettuce. They can also be present in fertilizers and industrial waste, which can contaminate groundwater and surface water sources. While nitrates themselves are not harmful, they can be converted into potentially harmful compounds called nitrites under certain conditions, particularly in the digestive system of young children or in the presence of bacteria such as those found in unpasteurized foods. Excessive levels of nitrites can react with hemoglobin in the blood to form methemoglobin, which cannot transport oxygen effectively and can lead to a condition called methemoglobinemia.

Deoxyguanosine is a chemical compound that is a component of DNA (deoxyribonucleic acid), one of the nucleic acids. It is a nucleoside, which is a molecule consisting of a sugar (in this case, deoxyribose) and a nitrogenous base (in this case, guanine). Deoxyguanosine plays a crucial role in the structure and function of DNA, as it pairs with deoxycytidine through hydrogen bonding to form a rung in the DNA double helix. It is involved in the storage and transmission of genetic information.

The cerebral cortex is the outermost layer of the brain, characterized by its intricate folded structure and wrinkled appearance. It is a region of great importance as it plays a key role in higher cognitive functions such as perception, consciousness, thought, memory, language, and attention. The cerebral cortex is divided into two hemispheres, each containing four lobes: the frontal, parietal, temporal, and occipital lobes. These areas are responsible for different functions, with some regions specializing in sensory processing while others are involved in motor control or associative functions. The cerebral cortex is composed of gray matter, which contains neuronal cell bodies, and is covered by a layer of white matter that consists mainly of myelinated nerve fibers.

Luminescent measurements refer to the quantitative assessment of the emission of light from a substance that has been excited, typically through some form of energy input such as electrical energy or radiation. In the context of medical diagnostics and research, luminescent measurements can be used in various applications, including bioluminescence imaging, which is used to study biological processes at the cellular and molecular level.

Bioluminescence occurs when a chemical reaction produces light within a living organism, often through the action of enzymes such as luciferase. By introducing a luciferase gene into cells or organisms, researchers can use bioluminescent measurements to track cellular processes and monitor gene expression in real time.

Luminescent measurements may also be used in medical research to study the properties of materials used in medical devices, such as LEDs or optical fibers, or to develop new diagnostic tools based on light-emitting nanoparticles or other luminescent materials.

In summary, luminescent measurements are a valuable tool in medical research and diagnostics, providing a non-invasive way to study biological processes and develop new technologies for disease detection and treatment.

Enzyme activation refers to the process by which an enzyme becomes biologically active and capable of carrying out its specific chemical or biological reaction. This is often achieved through various post-translational modifications, such as proteolytic cleavage, phosphorylation, or addition of cofactors or prosthetic groups to the enzyme molecule. These modifications can change the conformation or structure of the enzyme, exposing or creating a binding site for the substrate and allowing the enzymatic reaction to occur.

For example, in the case of proteolytic cleavage, an inactive precursor enzyme, known as a zymogen, is cleaved into its active form by a specific protease. This is seen in enzymes such as trypsin and chymotrypsin, which are initially produced in the pancreas as inactive precursors called trypsinogen and chymotrypsinogen, respectively. Once they reach the small intestine, they are activated by enteropeptidase, a protease that cleaves a specific peptide bond, releasing the active enzyme.

Phosphorylation is another common mechanism of enzyme activation, where a phosphate group is added to a specific serine, threonine, or tyrosine residue on the enzyme by a protein kinase. This modification can alter the conformation of the enzyme and create a binding site for the substrate, allowing the enzymatic reaction to occur.

Enzyme activation is a crucial process in many biological pathways, as it allows for precise control over when and where specific reactions take place. It also provides a mechanism for regulating enzyme activity in response to various signals and stimuli, such as hormones, neurotransmitters, or changes in the intracellular environment.

Ethylenediamines are organic compounds that contain two amine groups (-NH2) separated by two methylene bridges (-CH2-). The general formula for ethylenediamines is C2H8N2. They can act as a chelating agent, forming stable complexes with many metal ions. Ethylenediamines are used in various industrial and pharmaceutical applications, including the manufacture of resins, textile dyes, and as a solvent for cellulose acetate. In medicine, they can be used as a vasodilator and in the treatment of urinary tract infections.

Butylated hydroxyanisole (BHA) is a synthetic antioxidant that is commonly used as a food additive to prevent or slow down the oxidation of fats, oils, and other lipids. This helps to maintain the quality, stability, and safety of food products by preventing rancidity and off-flavors. BHA is also used in cosmetics, pharmaceuticals, and animal feeds for similar purposes.

In medical terms, BHA is classified as a chemical preservative and antioxidant. It is a white or creamy white crystalline powder that is soluble in alcohol and ether but insoluble in water. BHA is often used in combination with other antioxidants, such as butylated hydroxytoluene (BHT), to provide a synergistic effect and enhance the overall stability of food products.

While BHA is generally recognized as safe by regulatory agencies such as the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA), some studies have suggested that high doses of BHA may have potential health risks, including possible carcinogenic effects. However, these findings are not conclusive, and further research is needed to fully understand the potential health impacts of BHA exposure.

Metalloporphyrins are a type of porphyrin molecule that contain a metal ion at their center. Porphyrins are complex organic compounds containing four modified pyrrole rings connected to form a planar, aromatic ring known as a porphine. When a metal ion is incorporated into the center of the porphyrin ring, it forms a metalloporphyrin.

These molecules have great biological significance, as they are involved in various essential processes within living organisms. For instance, heme, a type of iron-containing porphyrin, plays a crucial role in oxygen transport and storage in the body by forming part of hemoglobin and myoglobin molecules. Chlorophyll, another metalloporphyrin with magnesium at its center, is essential for photosynthesis in plants, algae, and some bacteria.

Metalloporphyrins have also found applications in several industrial and medical fields, including catalysis, sensors, and pharmaceuticals. Their unique structure and properties make them valuable tools for researchers and scientists to study and utilize in various ways.

High-performance liquid chromatography (HPLC) is a type of chromatography that separates and analyzes compounds based on their interactions with a stationary phase and a mobile phase under high pressure. The mobile phase, which can be a gas or liquid, carries the sample mixture through a column containing the stationary phase.

In HPLC, the mobile phase is a liquid, and it is pumped through the column at high pressures (up to several hundred atmospheres) to achieve faster separation times and better resolution than other types of liquid chromatography. The stationary phase can be a solid or a liquid supported on a solid, and it interacts differently with each component in the sample mixture, causing them to separate as they travel through the column.

HPLC is widely used in analytical chemistry, pharmaceuticals, biotechnology, and other fields to separate, identify, and quantify compounds present in complex mixtures. It can be used to analyze a wide range of substances, including drugs, hormones, vitamins, pigments, flavors, and pollutants. HPLC is also used in the preparation of pure samples for further study or use.

'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.

Radiation-protective agents, also known as radioprotectors, are substances that help in providing protection against the harmful effects of ionizing radiation. They can be used to prevent or reduce damage to biological tissues, including DNA, caused by exposure to radiation. These agents work through various mechanisms such as scavenging free radicals, modulating cellular responses to radiation-induced damage, and enhancing DNA repair processes.

Radiation-protective agents can be categorized into two main groups:

1. Radiosensitizers: These are substances that make cancer cells more sensitive to the effects of radiation therapy, increasing their susceptibility to damage and potentially improving treatment outcomes. However, radiosensitizers do not provide protection to normal tissues against radiation exposure.

2. Radioprotectors: These agents protect both normal and cancerous cells from radiation-induced damage. They can be further divided into two categories: direct and indirect radioprotectors. Direct radioprotectors interact directly with radiation, absorbing or scattering it away from sensitive tissues. Indirect radioprotectors work by neutralizing free radicals and reactive oxygen species generated during radiation exposure, which would otherwise cause damage to cellular structures and DNA.

Examples of radiation-protective agents include antioxidants like vitamins C and E, chemical compounds such as amifostine and cysteamine, and various natural substances found in plants and foods. It is important to note that while some radiation-protective agents have shown promise in preclinical studies, their efficacy and safety in humans require further investigation before they can be widely used in clinical settings.

"Chromans" are a class of organic compounds that contain a benzene fused to a five-membered saturated carbon ring containing one oxygen atom. This particular ring structure is also known as a chromane. Chromans have various applications in the field of medicinal chemistry and pharmacology, with some derivatives exhibiting biological activities such as antioxidant, anti-inflammatory, and cardiovascular protective effects. Some well-known chroman derivatives include vitamin E (tocopherols and tocotrienols) and several synthetic drugs like chromanol, a calcium channel blocker used in the treatment of hypertension and angina pectoris.

Nitric oxide (NO) donors are pharmacological agents that release nitric oxide in the body when they are metabolized. Nitric oxide is a molecule that plays an important role as a signaling messenger in the cardiovascular, nervous, and immune systems. It helps regulate blood flow, relax smooth muscle, inhibit platelet aggregation, and modulate inflammatory responses.

NO donors can be used medically to treat various conditions, such as hypertension, angina, heart failure, and pulmonary hypertension, by promoting vasodilation and improving blood flow. Some examples of NO donors include nitroglycerin, isosorbide dinitrate, sodium nitroprusside, and molsidomine. These drugs work by releasing nitric oxide slowly over time, which then interacts with the enzyme soluble guanylate cyclase to produce cyclic guanosine monophosphate (cGMP), leading to relaxation of smooth muscle and vasodilation.

It is important to note that NO donors can have side effects, such as headache, dizziness, and hypotension, due to their vasodilatory effects. Therefore, they should be used under the guidance of a healthcare professional.

Hydrazines are not a medical term, but rather a class of organic compounds containing the functional group N-NH2. They are used in various industrial and chemical applications, including the production of polymers, pharmaceuticals, and agrochemicals. However, some hydrazines have been studied for their potential therapeutic uses, such as in the treatment of cancer and cardiovascular diseases. Exposure to high levels of hydrazines can be toxic and may cause damage to the liver, kidneys, and central nervous system. Therefore, medical professionals should be aware of the potential health hazards associated with hydrazine exposure.

A prostatectomy is a surgical procedure where all or part of the prostate gland is removed. This surgery can be performed through various approaches such as open surgery, laparoscopic surgery, or robotic-assisted surgery. The type of prostatectomy performed depends on the reason for the surgery and the patient's individual circumstances.

There are two main types of prostatectomies: radical and simple. A radical prostatectomy is a surgical procedure to remove the entire prostate gland, seminal vesicles, and surrounding lymph nodes. This type of prostatectomy is typically performed as a treatment for prostate cancer.

A simple prostatectomy, on the other hand, involves removing only the inner part of the prostate gland that is causing symptoms such as difficulty urinating or bladder obstruction. Simple prostatectomies are usually performed to alleviate benign prostatic hyperplasia (BPH), which is a non-cancerous enlargement of the prostate gland.

Regardless of the type of prostatectomy, potential risks and complications include bleeding, infection, urinary incontinence, erectile dysfunction, and changes in sexual function. It is important for patients to discuss these risks with their healthcare provider before undergoing surgery.

Peroxidases are a group of enzymes that catalyze the oxidation of various substrates using hydrogen peroxide (H2O2) as the electron acceptor. These enzymes contain a heme prosthetic group, which plays a crucial role in their catalytic activity. Peroxidases are widely distributed in nature and can be found in plants, animals, and microorganisms. They play important roles in various biological processes, including defense against oxidative stress, lignin degradation, and host-pathogen interactions. Some common examples of peroxidases include glutathione peroxidase, which helps protect cells from oxidative damage, and horseradish peroxidase, which is often used in laboratory research.

Paraquat is a highly toxic herbicide that is used for controlling weeds and grasses in agricultural settings. It is a non-selective contact weed killer, meaning it kills any green plant it comes into contact with. Paraquat is a fast-acting chemical that causes rapid desiccation of plant tissues upon contact.

In a medical context, paraquat is classified as a toxicological emergency and can cause severe poisoning in humans if ingested, inhaled, or comes into contact with the skin or eyes. Paraquat poisoning can lead to multiple organ failure, including the lungs, kidneys, and liver, and can be fatal in severe cases. There is no specific antidote for paraquat poisoning, and treatment typically focuses on supportive care and managing symptoms.

It's important to note that paraquat is highly regulated and its use is restricted to licensed professionals due to its high toxicity. Proper protective equipment, including gloves, goggles, and respiratory protection, should be used when handling paraquat to minimize the risk of exposure.

Macrophages are a type of white blood cell that are an essential part of the immune system. They are large, specialized cells that engulf and destroy foreign substances, such as bacteria, viruses, parasites, and fungi, as well as damaged or dead cells. Macrophages are found throughout the body, including in the bloodstream, lymph nodes, spleen, liver, lungs, and connective tissues. They play a critical role in inflammation, immune response, and tissue repair and remodeling.

Macrophages originate from monocytes, which are a type of white blood cell produced in the bone marrow. When monocytes enter the tissues, they differentiate into macrophages, which have a larger size and more specialized functions than monocytes. Macrophages can change their shape and move through tissues to reach sites of infection or injury. They also produce cytokines, chemokines, and other signaling molecules that help coordinate the immune response and recruit other immune cells to the site of infection or injury.

Macrophages have a variety of surface receptors that allow them to recognize and respond to different types of foreign substances and signals from other cells. They can engulf and digest foreign particles, bacteria, and viruses through a process called phagocytosis. Macrophages also play a role in presenting antigens to T cells, which are another type of immune cell that helps coordinate the immune response.

Overall, macrophages are crucial for maintaining tissue homeostasis, defending against infection, and promoting wound healing and tissue repair. Dysregulation of macrophage function has been implicated in a variety of diseases, including cancer, autoimmune disorders, and chronic inflammatory conditions.

Neutrophils are a type of white blood cell that are part of the immune system's response to infection. They are produced in the bone marrow and released into the bloodstream where they circulate and are able to move quickly to sites of infection or inflammation in the body. Neutrophils are capable of engulfing and destroying bacteria, viruses, and other foreign substances through a process called phagocytosis. They are also involved in the release of inflammatory mediators, which can contribute to tissue damage in some cases. Neutrophils are characterized by the presence of granules in their cytoplasm, which contain enzymes and other proteins that help them carry out their immune functions.

Scavenger receptors, class C (SR-C) are a group of membrane-bound receptors that play a crucial role in the recognition and clearance of damaged or apoptotic cells, as well as various types of pathogens and modified lipoproteins. These receptors belong to the superfamily of scavenger receptors, which share a common feature of broad and often overlapping ligand specificity.

SR-C receptors are characterized by their multi-ligand binding capacity, including oxidized low-density lipoprotein (oxLDL), advanced glycation end products (AGEs), and pathogen-associated molecular patterns (PAMPs). They contain several distinct structural domains, such as extracellular fibronectin type II (FNII) domains, transmembrane regions, and intracellular cytoplasmic tails.

There are three main members of the SR-C family: SR-CI, SR-CII, and SR-CIII. These receptors have been identified in various cell types, including macrophages, dendritic cells, endothelial cells, and fibroblasts. They contribute to several essential physiological processes, such as maintaining lipid homeostasis, modulating immune responses, and promoting tissue repair and remodeling.

Dysregulation of SR-C receptors has been implicated in the pathogenesis of various diseases, including atherosclerosis, diabetes, and autoimmune disorders. Therefore, understanding the structure and function of these receptors may provide valuable insights into developing novel therapeutic strategies for treating these conditions.

Iron carbonyl compounds are a group of chemical compounds that contain iron and carbon monoxide (CO) molecules. The most common iron carbonyl compound is Iron pentacarbonyl (Fe(CO)5), which is a colorless liquid with a faint, sweet odor. It is used as a reducing agent and a catalyst in various chemical reactions. Other iron carbonyl compounds include diiron decacarbonyl (Fe2(CO)10), triiron dodecacarbonyl (Fe3(CO)12), and tetracarbonylferrate(II) ion [Fe(CO)4]2-. These compounds are typically prepared by the direct reaction of iron with carbon monoxide under high pressure. They are sensitive to oxygen, moisture, and light, and must be handled carefully to prevent degradation.

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.

Krameriaceae is a family of flowering plants that includes around 6 genera and 170 species. These plants are primarily found in arid and semi-arid regions of Africa, with a few species occurring in Central America and the Caribbean. The family is characterized by having opposite leaves, flowers with four or five petals, and a unique type of fruit called a schizocarp that splits into one-seeded segments when ripe. Some well-known members of Krameriaceae include the prairie coneflower (Ratibida columnifera) and the Mexican hat (Ratibida coerulea).

Tyrosine is an non-essential amino acid, which means that it can be synthesized by the human body from another amino acid called phenylalanine. Its name is derived from the Greek word "tyros," which means cheese, as it was first isolated from casein, a protein found in cheese.

Tyrosine plays a crucial role in the production of several important substances in the body, including neurotransmitters such as dopamine, norepinephrine, and epinephrine, which are involved in various physiological processes, including mood regulation, stress response, and cognitive functions. It also serves as a precursor to melanin, the pigment responsible for skin, hair, and eye color.

In addition, tyrosine is involved in the structure of proteins and is essential for normal growth and development. Some individuals may require tyrosine supplementation if they have a genetic disorder that affects tyrosine metabolism or if they are phenylketonurics (PKU), who cannot metabolize phenylalanine, which can lead to elevated tyrosine levels in the blood. However, it is important to consult with a healthcare professional before starting any supplementation regimen.

Tocopherol and naringenin are bioactive free radical scavengers that act as antioxidants; synthetic catalytic scavengers are ... Their use is wide-ranged: In atmospheric chemistry, the most common scavenger is the hydroxyl radical, a short-lived radical ... Glutathione in the body scavenges oxidizing free radicals and peroxides and as a thiol nucleophile, attacks dangerous ... A scavenger in chemistry is a chemical substance added to a mixture in order to remove or de-activate impurities and unwanted ...
"Free Radical Scavengers and Antioxidants from Tagetes mendocina" (PDF). Verlag der Zeitschrift für Naturforschung. 59c: 345-353 ...
... produces Pironetin and the free radical scavengers benthocyanin A, benthocyanin B and benthocyanin C. ... A new free radical scavenger of microbial origin". Tetrahedron Letters. 32 (7): 943-946. doi:10.1016/S0040-4039(00)92126-9. ... new free radical scavengers from Streptomyces prunicolor". The Journal of Organic Chemistry. 58 (15): 4170-4172. doi:10.1021/ ... new free radical scavengers from Streptomyces prunicolor". The Journal of Organic Chemistry. 58 (15): 4170-4172. doi:10.1021/ ...
"Free radical scavengers from the Mexican herbal tea "poleo" (Hedeoma drummondii)". Zeitschrift für Naturforschung C. 63 (5-6): ...
These compounds have varying degrees of activity as free radical scavengers. It has been suggested that NAC is particularly ...
Inoscavin Kim, Jong-Pyung; Yun, Bong-Sik; Shim, Young Key; Yoo, Ick-Dong (1999). "Inoscavin A, a new free radical scavenger ...
By acting as free radical scavengers, further free radical reactions are prevented. Since 1947, BHA has been added to edible ... The conjugated aromatic ring of BHA is able to stabilize free radicals, sequestering them. ...
... s are radical scavengers, delivering an H atom to quench free radicals. At 323 kJ/mol, the O-H bond in tocopherols is ... This weak bond allows the vitamin to donate a hydrogen atom to the peroxyl radical and other free radicals, minimizing their ... All feature a chromane ring, with a hydroxyl group that can donate a hydrogen atom to reduce free radicals and a hydrophobic ... Plasma F2-isoprostane concentration was selected as a biomarker of free radical-mediated lipid peroxidation. Only the two ...
... is a hydroxyl (OH) free radical scavenger. Scymnol's role in quenching free radicals may play a role in ... The molecule is a steroid derivative that behaves as a hydroxyl radical scavenger and is used for the treatment of skin ... ISBN 978-3-319-45850-2. Macrides et al, A comparison of the hydroxyl radical scavenging properties of the shark bile steroid 5β ...
"Buckminsterfullerenol Free Radical Scavengers Reduce Excitotoxic and Apoptotic Death of Cultured Cortical Neurons". ... A free radical-scavenging nanosponge was engineered for ischemic stroke. A minireview was published on gold-conjugate-based ... "Bioinspired Nanosponge for Salvaging Ischemic Stroke via Free Radical Scavenging and Self-Adapted Oxygen Regulating". Nano ... A nanozyme for metal-free bioinspired cascade photocatalysis was reported. Chemical Society Reviews published a tutorial review ...
"Free radical scavengers vitamins A, C, and E plus magnesium reduce noise trauma". Free Radical Biology and Medicine. Elsevier ...
... acts as a free radical scavenger for radicals such as the hydroxyl radical (•OH) radical. It is used as free radical ... "Evidence for direct interactions between methimazole and free radicals". FEBS Letters. 176 (2): 337-340. doi:10.1016/0014-5793( ... scavenger in organic chemistry. Thiamazole is also indicated in cats to treat hyperthyroidism. "DrugBank: Methimazole (DB00763 ...
... scavenger of free radicals, toxicity, and disease, cleanser of ecosystems; and lastly, essence of beauty and comfort from ...
Edaravone is a synthetic-free radical scavenger and has been proved to be effective. Edaravone protects the brain by ... eliminating excessive free radicals, which are highly reactive molecules occurring in the human body as a result of stroke, an ...
It functions as an intracellular free radical scavenger to protect DNA from free radical attack. Spermine is the chemical ... "The natural polyamine spermine functions directly as a free radical scavenger". PNAS. 95 (19): 11140. doi:10.1073/pnas.95.19. ...
"Biologically active alkaloids and a free radical scavenger from Prosopis species". J Ethnopharmacol. 71 (1-2): 241-6. doi: ...
... is recognized as being a particularly efficient free radical scavenger. It is able to scavenge and degrade free ... radicals and reactive oxygen species in the body, and inhibits enzymes involved in the generation of these reactive oxygen ...
Useful as .OH scavengers?". Free Radical Research Communications. 16 (3): 197-204. doi:10.3109/10715769209049172. PMID 1318253 ... Eugenol itself is known to be incompatible with resin polymers, as it is a radical scavenger (like other phenolic compounds) ... there is no difference in bond strengths of self-adhesive resin cements to dentine between prior application of eugenol free ...
Used as a free radical scavenger in trichloromethane (chloroform) and dichloromethane (methylene chloride). It is also used to ...
Intravenous DMSO is sometimes used as a free-radical scavenger and anti-inflammatory. Additionally, wrapping the legs may ...
The reaction is insensitive to radical scavengers and therefore a free radical mechanism can be ruled out. The reaction ... Organolead compounds form a variety of reactive intermediates such as lead free radicals: Me3PbCl + Na (77 K) → Me3Pb. and ... n H2O The C-Pb bond is weak and for this reason homolytic cleavage of organolead compounds to free radicals is easy. In its ... anti-knocking capacity, its purpose is that of a radical initiator. General reaction types of aryl and vinyl organoleads are ...
Because of the weakness of the S−H bond, thiols can function as scavengers of free radicals. As the functional group of the ... doi:10.1016/b978-1-4160-5897-7.00004-4. ISBN 978-1-4160-5897-7. Sulfhydryls are scavengers of free radicals, protecting ... Free radicals derived from mercaptans, called thiyl radicals, are commonly invoked to explain reactions in organic chemistry ... Thiyl radicals (sulfur-centred) can transform to carbon-centred radicals via hydrogen atom exchange equilibria. The formation ...
"Postasphyxial cerebral survival in newborn sheep after treatment with oxygen free radical scavengers and a calcium antagonist ... Free radical production is lessened, which protects cells and cellular organelles from oxidative damage during reperfusion. In ... Globus MY, Alonso O, Dietrich WD, Busto R, Ginsberg MD (October 1995). "Glutamate release and free radical production following ... The radical idea that hypoxia-ischaemia triggered a cell suicide programme which could explain the perplexing phenomenon of ...
... was first reported as a potent antioxidant and free radical scavenger in 1993. In vitro, melatonin acts as a direct ... Melatonin also acts as a high-capacity free radical scavenger within mitochondria which also promotes the expression of ... Due to its capacity for free radical scavenging, indirect effects on the expression of antioxidant enzymes, and its significant ... Reiter RJ, Acuña-Castroviejo D, Tan DX, Burkhardt S (June 2001). "Free radical-mediated molecular damage. Mechanisms for the ...
Mahajan M, Kaur S, Mahajan S, Kant R (April 2009). "Uric acid a better scavenger of free radicals than vitamin C in rheumatoid ... due to free radical damage. Hypouricemia is benign and not a medical condition, but it is a useful medical sign. It is usually ...
Kang HS, Kim KR, Jun EM, Park SH, Lee TS, Suh JW, Kim JP (2008). "Cyathuscavins A, B, and C, new free radical scavengers with ...
It is a very good scavenger of free radicals, and it can be used for controlling radical polymerizations. Fullerene polymers ... In free radical copolymerization of styrene and C60 fullerene, the resulting copolymer is cross-linked and heterogeneous. Easy ... Examples of first approach are Diels-Alder addition and free radical copolymerization. Fullerene can be copolymerized with ... Bulky fullerene probably increases the free volume of PPO. Materials originating from polyurethane synthesis exhibit improved ...
In this role, vitamin E acts as a radical scavenger, delivering a hydrogen (H) atom to free radicals. At 323 kJ/mol, the O-H ... This weak bond allows the vitamin to donate a hydrogen atom to the peroxyl radical and other free radicals, minimizing their ... This removes the free radical intermediates and prevents the oxidation reaction from continuing. The oxidized α-tocopheroxyl ... Traber MG, Atkinson J (July 2007). "Vitamin E, antioxidant and nothing more". Free Radical Biology & Medicine. 43 (1): 4-15. ...
Kang HS, Kim KR, Jun EM, Park SH, Lee TS, Suh JW, Kim JP (2008). "Cyathuscavins A, B, and C, new free radical scavengers with ...
EGb 761 is seen to be neuroprotective; it is a free radical scavenger, improves mitochondrial function, and modulates serotonin ... A strict gluten-free diet started early may protect against dementia associated with gluten-related disorders. Cases of easily ... In those with celiac disease or non-celiac gluten sensitivity, a strict gluten-free diet may relieve the symptoms given a mild ... Once dementia is advanced no evidence suggests that a gluten-free diet is useful. Omega-3 fatty acid supplements do not appear ...
FRS Healthy Energy Products Energy is a vital, a precious resource. We need it to function and enjoy life. Many search for ways to get ...
The methanolic extract of the aerial parts exhibited a strong antioxidant effect measured by the scavenging of the free ... diphenyl picrylhydrazyl (DPPH) radical. Assay-guided fractionation of the crude methanolic extract allowed the identification ... Free Radical Scavengers from the Mexican Herbal Tea "Poleo" (Hedeoma drummondii). * Ezequiel Viveros-Valdez , Catalina Rivas- ... "Free Radical Scavengers from the Mexican Herbal Tea "Poleo" (Hedeoma drummondii)" Zeitschrift für Naturforschung C, vol. 63, no ...
One of the causes of disease is excessive free radical damage to your cells can harm your DNA and can cause problems in all ... more free radicals than whole foods and have fewer natural free radical scavengers to help protect you from those free radicals ... These all cause free radical damage too.. Free radical damage from toxins plays such a fundamental role in the development of ... Free Radical Scavengers. Home / Free Radical Scavengers One of the causes of disease is excessive free radical damage to your ...
PREVENTION+ An evolution of daily skin moisturizers with built-in broad spectrum UVA/UVB sun protection. Medical studies confirm that sun, pollution, stress and smoke are the leading causes of skin cancer and accelerated aging. Protect your skin daily with an IMAGE daily skin moisturizer formulated for your skin type.
1. They should be cautioned to discontinue allopurinol and to consult their physician immediately at the first sign of a skin rash, painful urination, blood in the urine, irritation of the eyes, or swelling of the lips or mouth ...
Dive into the research topics of Activation of NFκB and MnSOD gene expression by free radical scavengers in human ... Activation of NFκB and MnSOD gene expression by free radical scavengers in human microvascular endothelial cells. ...
Ascorbic Acid (vitamin C) is a water-soluble vitamin indicated for the prevention and treatment of scurvy, as ascorbic acid deficiency results in scurvy. Collagenous structures are primarily affected, and lesions develop in bones and blood vessels. Administration of ascorbic acid completely reverses the symptoms of ascorbic acid deficiency ...
Hemani Olive Oil Dietary Supplement Free Radical Scavenger 50 Capsule Rich in plentiful health benefits may help against bad ... Hemani Olive Oil Dietary Supplement Free Radical Scavenger 50 Capsule. Facebook Twitter Pinterest ... FREE RADICAL SCAVENGER. Rich in plentiful health benefits, the oil extracted from the fruit of Olive (Olea Europaea) tree is ... FREE RADICAL SCAVENGER. Rich in plentiful health benefits, the oil extracted from the fruit of Olive (Olea Europaea) tree is ...
... indicating that the extract was able to scavenge the free radicals in the irradiated drugs. This result suggest that its ... This work proposes a new method for the in vitro evaluation of the effect of UV irradiation on the production of free radicals ... addition to the antibiotics can help in the protection against the radicals formed during the exposition to solar light of ... A fast and simple FIA-chemiluminescence method for the evaluationof Roselle flowers as scavenger of the free radicals generated ...
Tocopherol and naringenin are bioactive free radical scavengers that act as antioxidants; synthetic catalytic scavengers are ... Their use is wide-ranged: In atmospheric chemistry, the most common scavenger is the hydroxyl radical, a short-lived radical ... Glutathione in the body scavenges oxidizing free radicals and peroxides and as a thiol nucleophile, attacks dangerous ... A scavenger in chemistry is a chemical substance added to a mixture in order to remove or de-activate impurities and unwanted ...
To develop more potent small molecules with enhanced free radical scavenger properties, a series of N-substituted isatin ... Chen, G., Wang, Y., Hao, X. et al. Simple isatin derivatives as free radical scavengers: Synthesis, biological evaluation and ... To develop more potent small molecules with enhanced free radical scavenger properties, a series of N-substituted isatin ... To develop more potent small molecules with enhanced free radical scavenger properties, a series of N-substituted isatin ...
Free Radical Scavengers * Lipid Peroxidation / drug effects * Male * Medicine, Traditional* * Microsomes, Liver / drug effects ... Using free radical-generating systems H. italicum. I. viscosa and F. suspensa protected against enzymatic and non-enzymatic ... Most of the extracts were weak scavengers of the hydroxyl radical and C. chinensis and P. cocos exhibited the highest ... lipid peroxidation in model membranes and also showed scavenging property on the superoxide radical. All extracts were assayed ...
Free radical scavenger, antioxidant. Chemical synthesis. Crocin and Safranal. Carotenoid. Lipophilic (poor water solubility). ... Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a strong free radical scavenger that suppresses the effect of oxidative ... Naito, R.; Nishinakamura, H.; Watanabe, T.; Nakayama, J.; Kodama, S. Edaravone, a free radical scavenger, accelerates wound ... Polyphenols from this plant were found to act as efficient scavengers of radical and non-radical reactive species, preventing ...
Rutin is a powerful combatant of free radicals and is best known for its role in vascular health. Rutin helps to maintain the ... Delivery: (Free Shipping) Add to your upcoming Autoship delivery. *Free shipping:Add-on items ship for free with your next ... Delivery: (Free Shipping) Add to your upcoming Autoship delivery. *Free shipping:Add-on items ship for free with your next ... Free Radical Scavenger. *Supports Vascular Strength. *Non-GMO. *A Dietary Supplement. *Vegetarian/Vegan ...
Fluoride impairs the production of free radical scavengers such as glutathione. Fluoride impairs the function of enzymes that ... After she had been symptom-free, the rash recurred at the same site with intense itching within an hour of receiving a test ...
1997), free radical scavengers (Kimura et al. 2012), matrix metalloprotease inhibitors (Tan et al. 2015), and application of ... Kimura K, Aoki J, Sakamoto Y et al (2012) Administration of edaravone, a free radical scavenger, during t-PA infusion can ... 2021). Macrophage scavenger receptor 1 (Msr1), also named Cd204, contribute to I/R injury when overexpressed; however, loss of ... 2011). Hemoglobin scavenger receptor Cd163 clears oxidative hemoglobin, leading to heme degradation by heme oxygenase-1 ...
These carotenoids are potent scavengers of free radicals in vitro. It is proposed using microglial cells that, due to their ... Free Radic. Biol. Med. 2012, 52, 59-69. [Google Scholar] [CrossRef] [PubMed] ... Rabot, S.; Membrez, M.; Bruneau, A.; Gérard, P.; Harach, T.; Moser, M.; Raymond, F.; Mansourian, R.; Chou, C.J. Germ-Free C57BL ... The diet of the subjects, although ad libitum with no calorie restrictions, except for a choline-free diet, thus did not ...
Of the 36 extracts, 18 (50 %) showed antifungal activity and free radical scavenging potency. 19 extracts were screened for ... free radicals, Gram positive (Enterococcus faecalis, Staphylococcus epidermidis and Staphylococcus aureus) and Gram negative ( ... Due to the free and open access to this great variety of biological resources, many Africans depend on them for their ... Keywords: Antibacterial, Antifungal, Côte dIvoire, Free radical scavengers, Medicinal plants.. View. Show abstract. ...
Free Radical Scavengers. Higdon JV, Frei B. 2003. Tea catechins and polyphenols: health effects, metabolism, and antioxidant ...
19] Glutathione is unstable in solution and effective as an oxygen free-radical scavenger only if it is added to UW solution ... Hydrogen peroxide then produces a cascade of oxygen free radicals, including hydroxyl radical and singlet oxygen, that are even ... which functions as an endogenous free-radical scavenger. [22] Therefore, glutathione and other agents that protect against ... 21] Oxygen free-radicals generated during reperfusion are the main cause of the reperfusion injury, but cytokines and nitric ...
... which means it acts as a free radical scavenger and absorbs oxygen free radicals.* ... Ginger also has a high oxygen radical absorbance capacity (ORAC), ...
Citrus bioflavonoids capacity to act as free radical scavengers. Antioxidants stop free radicals from damaging cells, which is ... This chemical has antioxidant capabilities, which aid in preventing tissue damage caused by free radicals. Free radicals are ... On the other hand, oxidative stress may be induced by an excess of free radicals, which may be brought on by a variety of ... Free radicals, which are unstable molecules, are capable of causing harm to cells. ...
Free Radicals, Scavengers, and Altered Genetic Molecules Freeman remarks: "The time scales of the reactions in an irradiated ... The threshold could be the dose rate at which the radiation-induced free radicals exceed the scavengers." We do not find the " ... Some Chemical Consequences: Free Radicals, Scavengers, Altered Genetic Molecules, p.3 *Intra-Track and Inter-Track ... If molecules which scavenge radicals and which are normally present in tissue greatly exceed in concentration the free radicals ...
Their broad spectrum of activities may probably be due to adjacent free hydroxyl groups. Protein activation and expression were ... which are both radical scavengers and cyclooxygenase inhibitors exhibiting anticancer activity. ... Gallic acid is a radical scavenger (Whang et al, 2005) and inhibits RR through chelating the tyrosyl radical required for RR ... Gallic acid and RV were also described as excellent free radical scavengers (Inoue et al, 1994; Isuzugawa et al, 2001; Kawada ...
Antioxidants are free radical scavengers. They eliminate these free radicals.... Drink Tea and Enjoy Good Health. ...
Antioxidants are free radical scavengers. They eliminate these free radicals.... Drink Tea and Enjoy Good Health. ...
Administration of a free-radical scavenger such as N-acetylcysteine.. *Hyperbaric oxygen therapy. ... The CCl3 radical is the key metabolite responsible for ultimate plasma membrane disruption and death of the cell. ...
Antioxidant and free radical scavenger. *Increases the look of skin elasticity. *1.7 oz ... Tags : Anti-Aging Apple Apricot Bio-Flavonoids Coconut Collagen Elastin Face Fine Lines Firming Free Radicals Gluten Free Gut ... Shopping just got easier! Pay over time with up to four interest-free installments. Learn More. ... Ingredients: Purified Water (Aqua), Carthamus Tinctorius (Safflower) Oleosomes (and) Water (Emulsifier-free Delivery System) (1 ...
  • Abundance in antioxidants, assists in preventing and neutralizing cell-damaging free radicals, promoting long-term wellbeing. (manmohni.pk)
  • Antioxidants are free radical scavengers. (diethealthclub.com)
  • Antioxidants are stable before and after donating their electron and will not set off a free radical chain reaction. (prohealth.com)
  • Antioxidants are free radical scavengers, helping to promote cell health. (prohealth.com)
  • Antioxidants also act as free radical scavengers. (mannatech.com)
  • However, antioxidants reduce free radicals by contributing electrons to help maintain molecular stability. (mannatech.com)
  • Antioxidants are chemicals that interact with and neutralize free radicals, thus preventing them from causing damage. (dentaleconomics.com)
  • Antioxidants terminate these chain reactions by removing free radical intermediates, and inhibiting further oxidation reactions. (dentaleconomics.com)
  • In a homeostatic state, there is a balance of ROS and antioxidants, and free radical tissue damage is not occurring. (dentaleconomics.com)
  • Addressing the free radical tissue damage manifesting as oxidative stress is the novel approach of antioxidants. (dentaleconomics.com)
  • Scientific investigations have demonstrated that free radical scavengers ("antioxidants") and agents that enhance the natural antioxidant systems can attenuate the harmful effects of noise or chemicals (or the combination of noise plus chemicals) on the inner ear. (cdc.gov)
  • The methanolic extract of the aerial parts exhibited a strong antioxidant effect measured by the scavenging of the free diphenyl picrylhydrazyl (DPPH) radical. (degruyter.com)
  • An antioxidant is a molecule capable of inhibiting the oxidation of another molecule, breaking the free radical chain of reactions. (prohealth.com)
  • Understanding how they work requires revisiting basic chemistry to understand the various events and processes that can cause cellular and tissue damage including oxidative stress, reactive oxygen species, free radicals, oxidation and reduction, and the mechanism of antioxidant action. (dentaleconomics.com)
  • Tissue damage occurs when free radicals overwhelm the antioxidant reserves in the body. (dentaleconomics.com)
  • Topical application of the polyphenol, antioxidant combination phloretin, and ferulic acid has been shown to neutralize free radical activity, enhance wound healing, and increase the number of tissue-building fibroblasts (AO ProVantage®, PerioSciences). (dentaleconomics.com)
  • Vitamin E is a fat-soluble vitamin that acts as an antioxidant and free-radical scavenger in lipophilic environments. (medscape.com)
  • All of the above mentioned conditions can disturb the oxidant-antioxidant balance of the organism and can trigger the formation of free radicals. (bvsalud.org)
  • Is alpha-lipoic acid a scavenger of reactive oxygen species in vivo? (oregonstate.edu)
  • There are many types of free radicals, and those that are of particular concern in biology are derived from oxygen and are called reactive oxygen species (ROS). (dentaleconomics.com)
  • The free radicals, including reactive oxygen species, can start chain reactions, which are very damaging to cells and tissues. (dentaleconomics.com)
  • Their use is wide-ranged: In atmospheric chemistry, the most common scavenger is the hydroxyl radical, a short-lived radical produced photolytically in the atmosphere. (wikipedia.org)
  • Most of the extracts were weak scavengers of the hydroxyl radical and C. chinensis and P. cocos exhibited the highest scavenging activity. (nih.gov)
  • Their broad spectrum of activities may probably be due to adjacent free hydroxyl groups. (nature.com)
  • Metronidazole, being electron-affinic, can accept an electron from neutral free radical centres to generate a reactive cation that binds to an anion such as hydroxyl (OH-), causing a permanent lesion. (who.int)
  • I. viscosa and F. suspensa protected against enzymatic and non-enzymatic lipid peroxidation in model membranes and also showed scavenging property on the superoxide radical. (nih.gov)
  • A scavenger in chemistry is a chemical substance added to a mixture in order to remove or de-activate impurities and unwanted reaction products, for example oxygen, to make sure that they will not cause any unfavorable reactions. (wikipedia.org)
  • Hydrazine and ascorbic acid are used as oxygen scavenger corrosion inhibitors. (wikipedia.org)
  • Oxygen scavengers or oxygen absorbers are small sachets or self adhesive labels that are placed inside modified atmosphere packs to help extend product life (notably cooked meats) and help improve product appearance. (wikipedia.org)
  • In general, the generation and scavenging of oxygen free radicals is balanced and any imbalance or excessive amounts of active radicals may contribute to disease development. (biomedcentral.com)
  • Ginger also has a high oxygen radical absorbance capacity (ORAC), which means it acts as a free radical scavenger and absorbs oxygen free radicals. (kroger.com)
  • Oral photoprotection can be achieved with free radical scavengers, thereby reducing free radicals, singlet oxygen formation, and the photosensitizing effect of porphyrins. (medscape.com)
  • Oxygen has two unpaired electrons, making oxygen especially susceptible to free radical formation. (dentaleconomics.com)
  • Radiosensitizers are chemical agents that have the potential to increase the lethal effect of radicals induced during irradiation [1-6].The extent of radiation damage to cells is dependent on the amount of oxygen available to the cell [1,2,7,8]. (who.int)
  • Under aerobic conditions, there is enough oxygen to react with all the free radicals and addition of metronidazole, or any other sensitizers, yields no further benefit. (who.int)
  • Free reactive oxygen radicals cause damage of mammalian cells by oxidizing fatty acids, protein and DNA. (bvsalud.org)
  • To develop more potent small molecules with enhanced free radical scavenger properties, a series of N -substituted isatin derivatives was synthesized, and the cytoprotective effect on the apoptosis of PC12 cells induced by H 2 O 2 was screened. (biomedcentral.com)
  • Free radicals are reactive molecules that can harm your cells. (mannatech.com)
  • It is then called a free radical, so free radicals are atoms or molecules that have one or more unpaired electrons. (dentaleconomics.com)
  • A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. (bvsalud.org)
  • In molecular laser isotope separation, methane is used as a scavenger gas for fluorine atoms. (wikipedia.org)
  • Glutathione in the body scavenges oxidizing free radicals and peroxides and as a thiol nucleophile, attacks dangerous alkylating electrophiles, which may be exogenous toxins or produced in the course of metabolism (e.g. (wikipedia.org)
  • The accumulated free radical damage is called oxidative stress. (dentaleconomics.com)
  • Oxidative stress occurs when the intracellular concentration of free radicals increases over the physiologic value. (bvsalud.org)
  • 2022.) As an anti-inflammatory and "free radical scavenger," melatonin may be therapeutic in preventing bone loss (Amstrup et al. (psychologytoday.com)
  • Flavonoids are known to be effective scavengers of free radicals. (koreamed.org)
  • Free radical damage from toxins plays such a fundamental role in the development of disease, it is no wonder some of the first supplements people think of taking for improving health are free radical scavenging vitamins. (gethealthyagain.com)
  • Toxins such as pollution, stress and even a poor diet can contribute to the creation of free radicals, which can lead to an acceleration of the aging process. (mannatech.com)
  • Depending on the pH, CeO2-NP acted as a free radical scavenger in an acidic environment (an environment mimicking the lysosome) while the NiO-NP acted as a scavenger in a physiological pH (an environment that mimics the cytosol of the cell). (cdc.gov)
  • CoQ10 functions as a potent free radical scavenger in cell membranes, as well as within blood vessels. (betterlife.com)
  • From resveratrol tablets to liposomal glutathione, these products are specifically created to help counter free radicals in the body to promote overall wellness. (prohealth.com)
  • Organic Teasel Extract, a free-radical scavengers that helps energize skin. (strawberrynet.com)
  • Phytoprostanes (PhytoPs) and phytofurans (PhytoFs) are plant oxylipins (isoprostane-prostaglandin-like compounds) formed by the free radical-catalyzed oxidation of α-linolenic acid (ALA, C18:3, n-3). (researchgate.net)
  • Another reason we have too much free radical damage is that processed foods generate more free radicals than whole foods and have fewer natural free radical scavengers to help protect you from those free radicals. (gethealthyagain.com)
  • Sigma Chemical Company, Germany, un- radical centres to generate a reactive cation less otherwise mentioned. (who.int)
  • One of the causes of disease is excessive free radical damage to your cells can harm your DNA and can cause problems in all sorts of ways. (gethealthyagain.com)
  • Therefore, it is important to find effective scavengers of free radicals for prevention and treatment of such disorders. (biomedcentral.com)
  • That is, spasticity must be controlled, nutritional status must be optimized, and the wound must be clean and free of infection. (medscape.com)
  • Of particular interest to dental professionals is the elevation of free radicals in the presence of infection. (dentaleconomics.com)
  • WB by Hemani Herbal Dietary Supplements are made with 100% natural & herbal oils and are vegan, and gluten-free. (manmohni.pk)
  • Mediante la educación ambiental se busca concientizar a las personas sobre los problemas del ambiente natural y social desde su formación escolar en la niñez para generar valores, nuevas actitudes, comportamientos y creencias orientadas al cuidado del medio ambiente y el aprendizaje de nuevas relaciones entre las personas. (bvsalud.org)
  • In the process, byproducts - free radicals - are created that oxidize and break down tissues. (prohealth.com)
  • The CCl 3 radical is the key metabolite responsible for ultimate plasma membrane disruption and death of the cell. (cdc.gov)
  • Cell death and hearing loss from noise and/or chemicals are now thought to be at least, in part, a consequence of metabolic stress that results in toxic accumulation of free radicals. (cdc.gov)
  • 2 of free radicals from the stimulation of available to the cell [ 1,2,7,8 ]. (who.int)
  • Digalloyl-resveratrol (di-GA) is a synthetic compound aimed to combine the biological effects of the plant polyhydroxy phenols gallic acid and resveratrol, which are both radical scavengers and cyclooxygenase inhibitors exhibiting anticancer activity. (nature.com)
  • Metronidazole selectively radiosensitizes of metronidazole (in a range of therapeutic hypoxic cells without influencing the ra- concentrations) on PMN-generated free diation response of normal well-oxygenated radicals during phagocytosis activity in cells [ 5,7-9 ]. (who.int)
  • PMN results in the production of super- cer cells are known to be relatively resistant oxide radicals [ 7,8 ]. (who.int)
  • Free shipping is available for selected shipping service. (iherb.com)
  • Sign-up for our free monthly Longevity Today newsletter and receive exclusive offers, free shipping events, health tips and more! (prohealth.com)
  • FREE Shipping Anywhere in the world! (strawberrynet.com)
  • Using free radical-generating systems H. italicum. (nih.gov)