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.
Industrial products consisting of a mixture of chlorinated biphenyl congeners and isomers. These compounds are highly lipophilic and tend to accumulate in fat stores of animals. Many of these compounds are considered toxic and potential environmental pollutants.
Biphenyl compounds which are extensively brominated. Many of these compounds are toxic environmental pollutants.
Industrial chemicals which have become widespread environmental pollutants. Each aroclor is a mixture of chlorinated biphenyls (1200 series) or chlorinated terphenyls (5400 series) or a combination of both (4400 series).
Substances or energies, for example heat or light, which when introduced into the air, water, or land threaten life or health of individuals or ECOSYSTEMS.
Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.
Hydrocarbon compounds with one or more of the hydrogens replaced by CHLORINE.
An organochlorine pesticide, it is the ethylene metabolite of DDT.
Chlorinated hydrocarbons containing heteroatoms that are present as contaminants of herbicides. Dioxins are carcinogenic, teratogenic, and mutagenic. They have been banned from use by the FDA.
A family of gram negative, aerobic, non-sporeforming, rod-shaped bacteria.
Non-heme iron-containing enzymes that incorporate two atoms of OXYGEN into the substrate. They are important in biosynthesis of FLAVONOIDS; GIBBERELLINS; and HYOSCYAMINE; and for degradation of AROMATIC HYDROCARBONS.
Compounds that contain a BENZENE ring fused to a furan ring.
Materials applied to fabrics, bedding, furniture, plastics, etc. to retard their burning; many may leach out and cause allergies or other harm.
A bacterial genus of the order ACTINOMYCETALES.
Substances which pollute the soil. Use for soil pollutants in general or for which there is no specific heading.
A genus of gram-negative, aerobic, rod-shaped bacteria. Organisms in this genus had originally been classified as members of the PSEUDOMONAS genus but overwhelming biochemical and chemical findings indicated the need to separate them from other Pseudomonas species, and hence, this new genus was created.
The geographic area of the Great Lakes in general and when the specific state or states are not indicated. It usually includes Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin.
The presence in food of harmful, unpalatable, or otherwise objectionable foreign substances, e.g. chemicals, microorganisms or diluents, before, during, or after processing or storage.
An agricultural fungicide and seed treatment agent.
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.
Compounds that contain two halogenated benzene rings linked via an OXYGEN atom. Many polybrominated diphenyl ethers are used as FLAME RETARDANTS.
Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.
The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.
The total amount of a chemical, metal or radioactive substance present at any time after absorption in the body of man or animal.
A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.
Exposure of the female parent, human or animal, to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals that may affect offspring. It includes pre-conception maternal exposure.
Benzoic acid or benzoic acid esters substituted with one or more chlorine atoms.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Organic compounds containing carbon and hydrogen in the form of an unsaturated, usually hexagonal ring structure. The compounds can be single ring, or double, triple, or multiple fused rings.
A chemical by-product that results from burning or incinerating chlorinated industrial chemicals and other hydrocarbons. This compound is considered an environmental toxin, and may pose reproductive, as well as, other health risks for animals and humans.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
A highly poisonous organochlorine insecticide. The EPA has cancelled registrations of pesticides containing this compound with the exception of its use through subsurface ground insertion for termite control and the dipping of roots or tops of non-food plants. (From Merck Index, 11th ed)
Inorganic or organic compounds that contain sulfur as an integral part of the molecule.
Chemicals used to destroy pests of any sort. The concept includes fungicides (FUNGICIDES, INDUSTRIAL); INSECTICIDES; RODENTICIDES; etc.
A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.
Placing of a hydroxyl group on a compound in a position where one did not exist before. (Stedman, 26th ed)
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
Organic compounds that have a relatively high VAPOR PRESSURE at room temperature.
Halogenated hydrocarbons refer to organic compounds containing carbon and hydrogen atoms, where one or more hydrogen atoms are replaced by halogens such as fluorine, chlorine, bromine, or iodine.
Pesticides or their breakdown products remaining in the environment following their normal use or accidental contamination.
The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.
Created 1 January 1993 as a result of the division of Czechoslovakia into the Czech Republic and Slovakia.
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.
Pesticides designed to control insects that are harmful to man. The insects may be directly harmful, as those acting as disease vectors, or indirectly harmful, as destroyers of crops, food products, or textile fabrics.
The relationship between the dose of an administered drug and the response of the organism to the drug.
A greenish-yellow, diatomic gas that is a member of the halogen family of elements. It has the atomic symbol Cl, atomic number 17, and atomic weight 70.906. It is a powerful irritant that can cause fatal pulmonary edema. Chlorine is used in manufacturing, as a reagent in synthetic chemistry, for water purification, and in the production of chlorinated lime, which is used in fabric bleaching.
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
A liver microsomal cytochrome P-450 monooxygenase capable of biotransforming xenobiotics such as polycyclic hydrocarbons and halogenated aromatic hydrocarbons into carcinogenic or mutagenic compounds. They have been found in mammals and fish. This enzyme, encoded by CYP1A1 gene, can be measured by using ethoxyresorufin as a substrate for the ethoxyresorufin O-deethylase activity.
Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
'Human Milk' is the secretion from human mammary glands, primarily composed of water, carbohydrates, fats, proteins, and various bioactive components, which serves as the complete source of nutrition for newborn infants, supporting their growth, development, and immune system.
Exogenous agents, synthetic and naturally occurring, which are capable of disrupting the functions of the ENDOCRINE SYSTEM including the maintenance of HOMEOSTASIS and the regulation of developmental processes. Endocrine disruptors are compounds that can mimic HORMONES, or enhance or block the binding of hormones to their receptors, or otherwise lead to activating or inhibiting the endocrine signaling pathways and hormone metabolism.
A polychlorinated pesticide that is resistant to destruction by light and oxidation. Its unusual stability has resulted in difficulties in residue removal from water, soil, and foodstuffs. This substance may reasonably be anticipated to be a carcinogen: Fourth Annual Report on Carcinogens (NTP-85-002, 1985). (From Merck Index, 11th ed)
Compounds consisting of two or more fused ring structures.
I'm sorry for any confusion, but the term "Michigan" is not a medical concept or condition that has a defined meaning within the medical field. It refers to a state in the United States, and does not have a direct medical connotation.
The consequences of exposing the FETUS in utero to certain factors, such as NUTRITION PHYSIOLOGICAL PHENOMENA; PHYSIOLOGICAL STRESS; DRUGS; RADIATION; and other physical or chemical factors. These consequences are observed later in the offspring after BIRTH.
Chemicals that kill or inhibit the growth of fungi in agricultural applications, on wood, plastics, or other materials, in swimming pools, etc.
A species of gram-negative bacteria in the genus PSEUDOMONAS. All strains can utilize FRUCTOSE for energy. It is occasionally isolated from humans and some strains are pathogenic to WATERMELON.
Ethers that are linked to a benzene ring structure.
The concentration of a compound needed to reduce population growth of organisms, including eukaryotic cells, by 50% in vitro. Though often expressed to denote in vitro antibacterial activity, it is also used as a benchmark for cytotoxicity to eukaryotic cells in culture.
An insecticide and herbicide that has also been used as a wood preservative. Pentachlorphenol is a widespread environmental pollutant. Both chronic and acute pentachlorophenol poisoning are medical concerns. The range of its biological actions is still being actively explored, but it is clearly a potent enzyme inhibitor and has been used as such as an experimental tool.
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.
A plant genus of the family BRASSICACEAE known for the root used in hot SPICES. It is also the source of HORSERADISH PEROXIDASE which is widely used in laboratories.
The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
Preclinical testing of drugs in experimental animals or in vitro for their biological and toxic effects and potential clinical applications.
The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.
Organic compounds in which mercury is attached to a methyl group.
Derivatives of BENZOIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxybenzene structure.
Chlorobenzenes are organic compounds consisting of a benzene ring substituted with one or more chlorine atoms, used as solvents, refrigerants, and intermediates in the production of other chemicals, but with limited use due to environmental and health concerns.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
An organochlorine insecticide that is slightly irritating to the skin. (From Merck Index, 11th ed, p482)
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
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).
Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.
Ring compounds having atoms other than carbon in their nuclei. (Grant & Hackh's Chemical Dictionary, 5th ed)
A widely used industrial solvent.
A major group of unsaturated cyclic hydrocarbons containing two or more rings. The vast number of compounds of this important group, derived chiefly from petroleum and coal tar, are rather highly reactive and chemically versatile. The name is due to the strong and not unpleasant odor characteristic of most substances of this nature. (From Hawley's Condensed Chemical Dictionary, 12th ed, p96)
'Benzene derivatives' are organic compounds that contain a benzene ring as the core structure, with various functional groups attached to it, and can have diverse chemical properties and uses, including as solvents, intermediates in chemical synthesis, and pharmaceuticals.
Compounds with a 5-membered ring of four carbons and an oxygen. They are aromatic heterocycles. The reduced form is tetrahydrofuran.
Compounds containing the -SH radical.
An increase in the rate of synthesis of an enzyme due to the presence of an inducer which acts to derepress the gene responsible for enzyme synthesis.
A member of the BENZODIOXOLES that is a constituent of several VOLATILE OILS, notably SASSAFRAS oil. It is a precursor in the synthesis of the insecticide PIPERONYL BUTOXIDE and the drug N-methyl-3,4-methylenedioxyamphetamine (MDMA).
Large collections of small molecules (molecular weight about 600 or less), of similar or diverse nature which are used for high-throughput screening analysis of the gene function, protein interaction, cellular processing, biochemical pathways, or other chemical interactions.
A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)
A species of gram-negative, aerobic rods formerly called Pseudomonas testosteroni. It is differentiated from other Comamonas species by its ability to assimilate testosterone and to utilize phenylacetate or maleate as carbon sources.
The rate dynamics in chemical or physical systems.
A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.
The system of glands that release their secretions (hormones) directly into the circulatory system. In addition to the ENDOCRINE GLANDS, included are the CHROMAFFIN SYSTEM and the NEUROSECRETORY SYSTEMS.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
Phylum of green nonsulfur bacteria including the family Chloroflexaceae, among others.
A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.
Organic compounds which contain tin in the molecule. Used widely in industry and agriculture.
A group of 1,2-benzenediols that contain the general formula R-C6H5O2.
Damages to reproductive health prior to conception (FERTILIZATION), a legal term for torts liability concerning environmental safety issues. Preconception injuries may involve either the male or the female, such as chromosomal mutations in the OVA or the SPERMATOZOA.
Inorganic compounds that contain chlorine as an integral part of the molecule.
A genus of gram-negative, aerobic, rod-shaped bacteria characterized by an outer membrane that contains glycosphingolipids but lacks lipopolysaccharide. They have the ability to degrade a broad range of substituted aromatic compounds.
The physical effects involving the presence of electric charges at rest and in motion.
Aniline compounds, also known as aromatic amines, are organic chemicals derived from aniline (aminobenzene), characterized by the substitution of hydrogen atoms in the benzene ring with amino groups (-NH2).
Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.
Contamination of the air, bodies of water, or land with substances that are harmful to human health and the environment.
A group of compounds consisting in part of two rings sharing one atom (usually a carbon) in common.
A broad class of substances containing carbon and its derivatives. Many of these chemicals will frequently contain hydrogen with or without oxygen, nitrogen, sulfur, phosphorus, and other elements. They exist in either carbon chain or carbon ring form.
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
A family of isomeric, colorless aromatic hydrocarbon liquids, that contain the general formula C6H4(CH3)2. They are produced by the destructive distillation of coal or by the catalytic reforming of petroleum naphthenic fractions. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
Inorganic compounds that contain nitrogen as an integral part of the molecule.
A genus of gram-negative, aerobic, motile bacteria that occur in water and soil. Some are common inhabitants of the intestinal tract of vertebrates. These bacteria occasionally cause opportunistic infections in humans.
Covalent attachment of HALOGENS to other compounds.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A very complex, but reproducible mixture of at least 177 C10 polychloro derivatives, having an approximate overall empirical formula of C10-H10-Cl8. It is used as an insecticide and may reasonably be anticipated to be a carcinogen: Fourth Annual Report on Carcinogens (NTP 85-002, 1985). (From Merck Index, 11th ed)
Cytoplasmic proteins that bind certain aryl hydrocarbons, translocate to the nucleus, and activate transcription of particular DNA segments. AH receptors are identified by their high-affinity binding to several carcinogenic or teratogenic environmental chemicals including polycyclic aromatic hydrocarbons found in cigarette smoke and smog, heterocyclic amines found in cooked foods, and halogenated hydrocarbons including dioxins and polychlorinated biphenyls. No endogenous ligand has been identified, but an unknown natural messenger with a role in cell differentiation and development is suspected.
A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.
A central nervous system stimulant. It was formerly used in the treatment of barbiturate overdose but is now considered to be of no value for such purposes and may be dangerous. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1229)
Adverse effect upon bodies of water (LAKES; RIVERS; seas; groundwater etc.) caused by CHEMICAL WATER POLLUTANTS.
The characteristic three-dimensional shape of a molecule.
The molecular designing of drugs for specific purposes (such as DNA-binding, enzyme inhibition, anti-cancer efficacy, etc.) based on knowledge of molecular properties such as activity of functional groups, molecular geometry, and electronic structure, and also on information cataloged on analogous molecules. Drug design is generally computer-assisted molecular modeling and does not include pharmacokinetics, dosage analysis, or drug administration analysis.
Nitroso compounds are organic or inorganic substances containing the nitroso functional group, which consists of a nitrogen atom bonded to an oxygen atom through a single covalent bond, often abbreviated as -NO.
A fungistatic compound that is widely used as a food preservative. It is conjugated to GLYCINE in the liver and excreted as hippuric acid.
A class of compounds of the type R-M, where a C atom is joined directly to any other element except H, C, N, O, F, Cl, Br, I, or At. (Grant & Hackh's Chemical Dictionary, 5th ed)
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
Organic compounds which contain selenium as an integral part of the molecule.
Methods of investigating the effectiveness of anticancer cytotoxic drugs and biologic inhibitors. These include in vitro cell-kill models and cytostatic dye exclusion tests as well as in vivo measurement of tumor growth parameters in laboratory animals.
Exchange of substances between the maternal blood and the fetal blood at the PLACENTA via PLACENTAL CIRCULATION. The placental barrier excludes microbial or viral transmission.
A quantitative prediction of the biological, ecotoxicological or pharmaceutical activity of a molecule. It is based upon structure and activity information gathered from a series of similar compounds.
Inorganic compounds that contain bromine as an integral part of the molecule.
Phenanthrenes are aromatic hydrocarbons consisting of three benzene rings fused together in a linear arrangement, commonly found in various plants and some animals, and can act as precursors for certain steroid hormones or exhibit pharmacological activities with potential therapeutic uses.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
Organic compounds that contain phosphorus as an integral part of the molecule. Included under this heading is broad array of synthetic compounds that are used as PESTICIDES and DRUGS.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
The reactions and interactions of atoms and molecules, the changes in their structure and composition, and associated energy changes.
Azo compounds are organic compounds characterized by the presence of one or more azo groups, -N=N-, linking two aromatic rings, which can impart various colors and are used in dyes, pharmaceuticals, and chemical research.
Elements of limited time intervals, contributing to particular results or situations.
A drug-metabolizing, cytochrome P-450 enzyme which catalyzes the hydroxylation of aniline to hydroxyaniline in the presence of reduced flavoprotein and molecular oxygen. EC 1.14.14.-.
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.
Two-ring crystalline hydrocarbons isolated from coal tar. They are used as intermediates in chemical synthesis, as insect repellents, fungicides, lubricants, preservatives, and, formerly, as topical antiseptics.
**I'm really sorry, but I can't fulfill your request.**
Substances or organisms which pollute the water or bodies of water. Use for water pollutants in general or those for which there is no specific heading.
A plant genus of the family SALICACEAE. Members contain salicin, which yields SALICYLIC ACID.
A drug-metabolizing, cytochrome P-448 (P-450) enzyme which catalyzes the hydroxylation of benzopyrene to 3-hydroxybenzopyrene in the presence of reduced flavoprotein and molecular oxygen. Also acts on certain anthracene derivatives. An aspect of EC 1.14.14.1.
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
The functional hereditary units of BACTERIA.
Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.
Organic compounds that include a cyclic ether with three ring atoms in their structure. They are commonly used as precursors for POLYMERS such as EPOXY RESINS.

Irbesartan reduces QT dispersion in hypertensive individuals. (1/2256)

Angiotensin type 1 receptor antagonists have direct effects on the autonomic nervous system and myocardium. Because of this, we hypothesized that irbesartan would reduce QT dispersion to a greater degree than amlodipine, a highly selective vasodilator. To test this, we gathered electrocardiographic (ECG) data from a multinational, multicenter, randomized, double-blind parallel group study that compared the antihypertensive efficacy of irbesartan and amlodipine in elderly subjects with mild to moderate hypertension. Subjects were treated for 6 months with either drug. Hydrochlorothiazide and atenolol were added after 12 weeks if blood pressure (BP) remained uncontrolled. ECGs were obtained before randomization and at 6 months. A total of 188 subjects (118 with baseline ECGs) were randomized. We analyzed 104 subjects who had complete ECGs at baseline and after 6 months of treatment. Baseline characteristics between treatments were similar, apart from a slight imbalance in diastolic BP (irbesartan [n=53] versus amlodipine [n=51], 99.2 [SD 3. 6] versus 100.8 [3.8] mm Hg; P=0.03). There were no significant differences in BP normalization (diastolic BP <90 mm Hg) between treatments at 6 months (irbesartan versus amlodipine, 80% versus 88%; P=0.378). We found a significant reduction in QT indexes in the irbesartan group (QTc dispersion mean, -11.4 [34.5] milliseconds, P=0.02; QTc max, -12.8 [35.5] milliseconds, P=0.01), and QTc dispersion did not correlate with the change in BP. The reduction in QT indexes with amlodipine (QTc dispersion, -9.7 [35.4] milliseconds, P=0.06; QTc max, -8.6 [33.2] milliseconds, P=0.07) did not quite reach statistical significance, but there was a correlation between the change in QT indexes and changes in systolic BP. In conclusion, irbesartan improved QT dispersion, and this effect may be important in preventing sudden cardiac death in at-risk hypertensive subjects.  (+info)

The cyclo-oxygenase-dependent regulation of rabbit vein contraction: evidence for a prostaglandin E2-mediated relaxation. (2/2256)

1. Arachidonic acid (0.01-1 microM) induced relaxation of precontracted rings of rabbit saphenous vein, which was counteracted by contraction at concentrations higher than 1 microM. Concentrations higher than 1 microM were required to induce dose-dependent contraction of vena cava and thoracic aorta from the same animals. 2. Pretreatment with a TP receptor antagonist (GR32191B or SQ29548, 3 microM) potentiated the relaxant effect in the saphenous vein, revealed a vasorelaxant component in the vena cava response and did not affect the response of the aorta. 3. Removal of the endothelium from the venous rings, caused a 10 fold rightward shift in the concentration-relaxation curves to arachidonic acid. Whether or not the endothelium was present, the arachidonic acid-induced relaxations were prevented by indomethacin (10 microM) pretreatment. 4. In the saphenous vein, PGE2 was respectively a 50 and 100 fold more potent relaxant prostaglandin than PGI2 and PGD2. Pretreatment with the EP4 receptor antagonist, AH23848B, shifted the concentration-relaxation curves of this tissue to arachidonic acid in a dose-dependent manner. 5. In the presence of 1 microM arachidonic acid, venous rings produced 8-10 fold more PGE2 than did aorta whereas 6keto-PGF1alpha and TXB2 productions remained comparable. 6. Intact rings of saphenous vein relaxed in response to A23187. Pretreatment with L-NAME (100 microM) or indomethacin (10 microM) reduced this response by 50% whereas concomitant pretreatment totally suppressed it. After endothelium removal, the remaining relaxing response to A23187 was prevented by indomethacin but not affected by L-NAME. 7. We conclude that stimulation of the cyclo-oxygenase pathway by arachidonic acid induced endothelium-dependent, PGE2/EP4 mediated relaxation of the rabbit saphenous vein. This process might participate in the A23187-induced relaxation of the saphenous vein and account for a relaxing component in the response of the vena cava to arachidonic acid. It was not observed in thoracic aorta because of the lack of a vasodilatory receptor and/or the poorer ability of this tissue than veins to produce PGE2.  (+info)

ACE inhibition and ANG II receptor blockade improve glomerular size-selectivity in IgA nephropathy. (3/2256)

Protein trafficking across the glomerular capillary has a pathogenic role in subsequent renal damage. Despite evidence that angiotensin-converting enzyme (ACE) inhibitors improve glomerular size-selectivity, whether this effect is solely due to ANG II blocking or if other mediators also play a contributory role is not clear yet. We studied 20 proteinuric patients with IgA nephropathy, who received either enalapril (20 mg/day) or the ANG II receptor blocker irbesartan (100 mg/day) for 28 days in a randomized double-blind study. Measurements of blood pressure, renal hemodynamics, and fractional clearance of neutral dextran of graded sizes were performed before and after 28 days of treatment. Both enalapril and irbesartan significantly reduced blood pressure over baseline. This reduction reached the maximum effect 4-6 h after drug administration but did not last for the entire 24-h period. Despite transient antihypertensive effect, proteinuria was effectively reduced by both treatments to comparable extents. Neither enalapril nor irbesartan modified the sieving coefficients of small dextran molecules, but both effectively reduced transglomerular passage of large test macromolecules. Theoretical analysis of sieving coefficients showed that neither drug affected significantly the mean pore radius or the spread of the pore-size distribution, but both importantly and comparably reduced the importance of a nonselective shunt pathway. These data suggest that antagonism of ANG II is the key mechanism by which ACE inhibitors exert their beneficial effect on glomerular size-selective function and consequently on glomerular filtration and urinary output of plasma proteins.  (+info)

Neurotensin is a proinflammatory neuropeptide in colonic inflammation. (4/2256)

The neuropeptide neurotensin mediates several intestinal functions, including chloride secretion, motility, and cellular growth. However, whether this peptide participates in intestinal inflammation is not known. Toxin A, an enterotoxin from Clostridium difficile, mediates pseudomembranous colitis in humans. In animal models, toxin A causes an acute inflammatory response characterized by activation of sensory neurons and intestinal nerves and immune cells of the lamina propria. Here we show that neurotensin and its receptor are elevated in the rat colonic mucosa following toxin A administration. Pretreatment of rats with the neurotensin receptor antagonist SR-48, 692 inhibits toxin A-induced changes in colonic secretion, mucosal permeability, and histologic damage. Exposure of colonic explants to toxin A or neurotensin causes mast cell degranulation, which is inhibited by SR-48,692. Because substance P was previously shown to mediate mast cell activation, we examined whether substance P is involved in neurotensin-induced mast cell degranulation. Our results show that neurotensin-induced mast cell degranulation in colonic explants is inhibited by the substance P (neurokinin-1) receptor antagonist CP-96,345, indicating that colonic mast activation in response to neurotensin involves release of substance P. We conclude that neurotensin plays a key role in the pathogenesis of C. difficile-induced colonic inflammation and mast cell activation.  (+info)

Angiotensin II receptor blockade in normotensive subjects: A direct comparison of three AT1 receptor antagonists. (5/2256)

Use of angiotensin (Ang) II AT1 receptor antagonists for treatment of hypertension is rapidly increasing, yet direct comparisons of the relative efficacy of antagonists to block the renin-angiotensin system in humans are lacking. In this study, the Ang II receptor blockade induced by the recommended starting dose of 3 antagonists was evaluated in normotensive subjects in a double-blind, placebo-controlled, randomized, 4-way crossover study. At 1-week intervals, 12 subjects received a single dose of losartan (50 mg), valsartan (80 mg), irbesartan (150 mg), or placebo. Blockade of the renin-angiotensin system was assessed before and 4, 24, and 30 hours after drug intake by 3 independent methods: inhibition of the blood pressure response to exogenous Ang II, in vitro Ang II receptor assay, and reactive changes in plasma Ang II levels. At 4 hours, losartan blocked 43% of the Ang II-induced systolic blood pressure increase; valsartan, 51%; and irbesartan, 88% (P<0.01 between drugs). The effect of each drug declined with time. At 24 hours, a residual effect was found with all 3 drugs, but at 30 hours, only irbesartan induced a marked, significant blockade versus placebo. Similar results were obtained when Ang II receptor blockade was assessed with an in vitro receptor assay and by the reactive rise in plasma Ang II levels. This study thus demonstrates that the first administration of the recommended starting dose of irbesartan induces a greater and longer lasting Ang II receptor blockade than that of valsartan and losartan in normotensive subjects.  (+info)

ESR study on the structure-antioxidant activity relationship of tea catechins and their epimers. (6/2256)

The purpose of this study is to examine the relationship between the free radical scavenging activities and the chemical structures of tea catechins ((-)-epigallocatechin gallate (EGCG), (-)-epigallocatechin (EGC) and (-)-epicatechin (EC)) and their corresponding epimers ((-)-gallocatechin gallate (GCG), (-)-gallocatechin (GC) and (+)-catechin ((+)-C)). With electron spin resonance (ESR) we investigated their scavenging effects on superoxide anions (O-.2) generated in the irradiated riboflavin system, singlet oxygen(1O2) generated in the photoradiation-hemoporphyrin system, the free radicals generated from 2,2'-azobis(2-amidinopropane)hydrochloride (AAPH) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. The results showed that the scavenging effects of galloylated catechins (EGCG and GCG) on the four free radicals were stronger than those of nongalloylated catechins (EGC, GC, EC, (+)-C), and the scavenging effects of EGC and GC were stronger than those of EC and (+)-C. Thus, it is suggested that the presence of the gallate group at the 3 position plays the most important role in their free radical-scavenging abilities and an additional insertion of the hydroxyl group at the 5' position in the B ring also contributes to their scavenging activities. Moreover, the corresponding phenoxyl radicals formed after the reaction with O-.2 were trapped by DMPO and the ESR spectra of DMPO/phenoxyl radical adducts were observed (aN=15.6 G and aHbeta=21.5 G). No significant differences were found between the scavenging effects of the catechins and their epimers when their concentrations were high. However, significant differences were observed at relatively low concentrations, and the lower their concentrations, the higher the differences. The scavenging abilities of GCG, GC and (+)-C were stronger than those of their corresponding epimers (EGCG, EGC and EC). The differences between their sterical structures played a more important role in their abilities to scavenge large free radicals, such as the free radicals generated from AAPH and the DPPH radical, than to scavenge small free radicals, such as O-.2 and 1O2, especially in the case with EGCG and GCG with more bulky steric hindrance.  (+info)

Serial changes in sarcoplasmic reticulum gene expression in volume-overloaded cardiac hypertrophy in the rat: effect of an angiotensin II receptor antagonist. (7/2256)

This study was designed to clarify whether gene expression in the cardiac sarcoplasmic reticulum [sarcoplasmic reticulum Ca2+-ATPase (SERCA), phospholamban, ryanodine receptor and calsequestrin] changes in accordance with left ventricular functional alterations in the volume-overloaded heart. Further, the effect of the angiotensin II type 1 receptor antagonist, TCV-116, on the expression of these genes was also evaluated. Left ventricular fractional shortening was significantly increased at 7 days, had returned to control levels at 21 days, and had significantly decreased at 35 days after the shunt operation, compared with sham-operated rats. The level of SERCA mRNA was significantly decreased at both 21 days and 35 days after the shunt operation. The levels of ryanodine receptor and phospholamban mRNAs were significantly decreased at 35 days in shunt-operated rats. The decrease in the SERCA mRNA level preceded the development of cardiac dysfunction. The levels of SERCA and ryanodine receptor mRNAs were correlated positively with left ventricular fractional shortening (r=0.73, P<0.0001 and r=0.61, P<0.01 respectively). Attenuation of the decrease in left ventricular fractional shortening occurred on treatment with TCV-116. After the treatment with TCV-116, the levels of SERCA and phospholamban mRNAs were restored to the respective values in sham-operated rats. Ryanodine receptor mRNA levels remained unchanged after treatment with TCV-116. These results indicate that the down-regulation of SERCA and ryanodine receptor mRNA levels may be related to cardiac dysfunction in the volume-overloaded heart. In addition, treatment with an angiotensin II receptor antagonist may restore the altered sarcoplasmic reticulum mRNA levels to control levels, and this may result in attenuation of the functional impairment in the volume-overloaded heart.  (+info)

Pharmacological diversity between native human 5-HT1B and 5-HT1D receptors sited on different neurons and involved in different functions. (8/2256)

The releases of [3H]5-hydroxytryptamine ([3H]5-HT) and of endogenous glutamic acid and their modulation through presynaptic h5-HT1B autoreceptors and h5-HT1D heteroreceptors have been investigated in synaptosomal preparations from fresh neocortical samples obtained from patients undergoing neurosurgery. The inhibition by 5-HT of the K+ (15 mM)-evoked overflow of [3H]5-HT was antagonized by the 5-HT1B/5-HT1D receptor ligand GR 127935, which was ineffective on its own; this drug was previously found to behave as a full agonist at the h5-HT1D heteroreceptor regulating glutamate release. The recently proposed selective h5-HT1B receptor ligand SB-224289 also prevented the effect of 5-HT at the autoreceptor, being inactive on its own; in contrast, SB-224289, at 1 microM, was unable to interact with the h5-HT1D heteroreceptor. The inhibitory effect of 5-HT on the K+-evoked overflow of glutamate was antagonized by the h5-HT1D receptor ligand BRL-15572; added in the absence of 5-HT the compound was without effect. BRL-15572 (1 microM) was unable to modify the effect of 5-HT at the autoreceptor regulating [3H]5-HT release. The selective 5-HT1A receptor antagonist (+)-WAY 100135, previously found to be an agonist at the h5-HT1D heteroreceptor regulating glutamate release, could not interact with the h5-HT1B autoreceptor when added at 1 microM. It is concluded that native h5-HT1B and h5-HT1D receptors exhibit a hitherto unexpected pharmacological diversity.  (+info)

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.

Polychlorinated biphenyls (PCBs) are a group of man-made organic chemicals consisting of 209 individual compounds, known as congeners. The congeners are formed by the combination of two benzene rings with varying numbers and positions of chlorine atoms.

PCBs were widely used in electrical equipment, such as transformers and capacitors, due to their non-flammability, chemical stability, and insulating properties. They were also used in other applications, including coolants and lubricants, plasticizers, pigments, and copy oils. Although PCBs were banned in many countries in the 1970s and 1980s due to their toxicity and environmental persistence, they still pose significant health and environmental concerns because of their continued presence in the environment and in products manufactured before the ban.

PCBs are known to have various adverse health effects on humans and animals, including cancer, immune system suppression, reproductive and developmental toxicity, and endocrine disruption. They can also cause neurological damage and learning and memory impairment in both human and animal populations. PCBs are highly persistent in the environment and can accumulate in the food chain, leading to higher concentrations in animals at the top of the food chain, including humans.

Polybrominated Biphenyls (PBBs) are a group of chemically related compounds that were widely used as flame retardants in various consumer products, such as electronics, appliances, and textiles. Structurally, they consist of two benzene rings with bromine atoms attached to them in different positions. PBBs have been banned or restricted in many countries due to their environmental persistence, bioaccumulation, and potential adverse health effects.

Here is a medical definition for Polybrominated Biphenyls (PBBs):

A class of brominated aromatic compounds that were historically used as flame retardants in various industrial and consumer applications. Due to their environmental persistence, bioaccumulation potential, and toxicity concerns, their production and use have been significantly restricted or banned in many countries. Exposure to PBBs can occur through ingestion, inhalation, or dermal contact and may lead to a variety of health issues, including endocrine disruption, reproductive and developmental effects, neurodevelopmental toxicity, and immune system alterations. Long-term exposure to high levels of PBBs can result in skin irritation, liver damage, and thyroid hormone disruption.

Aroclors are a series of polychlorinated biphenyl (PCB) mixtures that were manufactured by the Monsanto Company. They were widely used as cooling and insulating fluids in electrical equipment, such as transformers and capacitors, due to their non-flammability, chemical stability, and electrical insulating properties.

The term "Aroclor" is followed by a four-digit number that indicates the specific mixture and its average degree of chlorination. For example, Aroclor 1242 contains approximately 42% chlorine by weight, while Aroclor 1260 contains approximately 60% chlorine by weight.

Because of their persistence in the environment and potential toxicity to humans and wildlife, the production and use of PCBs, including Aroclors, were banned in the United States in 1979 under the Toxic Substances Control Act. However, due to their widespread historical use, PCBs continue to be a significant environmental pollutant and can still be found in many older electrical equipment, building materials, and soil and water samples.

Environmental pollutants are defined as any substances or energy (such as noise, heat, or light) that are present in the environment and can cause harm or discomfort to humans or other living organisms, or damage the natural ecosystems. These pollutants can come from a variety of sources, including industrial processes, transportation, agriculture, and household activities. They can be in the form of gases, liquids, solids, or radioactive materials, and can contaminate air, water, and soil. Examples include heavy metals, pesticides, volatile organic compounds (VOCs), particulate matter, and greenhouse gases.

It is important to note that the impact of environmental pollutants on human health and the environment can be acute (short-term) or chronic (long-term) and it depends on the type, concentration, duration and frequency of exposure. Some common effects of environmental pollutants include respiratory problems, cancer, neurological disorders, reproductive issues, and developmental delays in children.

It is important to monitor, control and reduce the emissions of these pollutants through regulations, technology advancements, and sustainable practices to protect human health and the environment.

Environmental biodegradation is the breakdown of materials, especially man-made substances such as plastics and industrial chemicals, by microorganisms such as bacteria and fungi in order to use them as a source of energy or nutrients. This process occurs naturally in the environment and helps to break down organic matter into simpler compounds that can be more easily absorbed and assimilated by living organisms.

Biodegradation in the environment is influenced by various factors, including the chemical composition of the substance being degraded, the environmental conditions (such as temperature, moisture, and pH), and the type and abundance of microorganisms present. Some substances are more easily biodegraded than others, and some may even be resistant to biodegradation altogether.

Biodegradation is an important process for maintaining the health and balance of ecosystems, as it helps to prevent the accumulation of harmful substances in the environment. However, some man-made substances, such as certain types of plastics and industrial chemicals, may persist in the environment for long periods of time due to their resistance to biodegradation, leading to negative impacts on wildlife and ecosystems.

In recent years, there has been increasing interest in developing biodegradable materials that can break down more easily in the environment as a way to reduce waste and minimize environmental harm. These efforts have led to the development of various biodegradable plastics, coatings, and other materials that are designed to degrade under specific environmental conditions.

Chlorinated hydrocarbons are a group of organic compounds that contain carbon (C), hydrogen (H), and chlorine (Cl) atoms. These chemicals are formed by replacing one or more hydrogen atoms in a hydrocarbon molecule with chlorine atoms. The properties of chlorinated hydrocarbons can vary widely, depending on the number and arrangement of chlorine and hydrogen atoms in the molecule.

Chlorinated hydrocarbons have been widely used in various industrial applications, including as solvents, refrigerants, pesticides, and chemical intermediates. Some well-known examples of chlorinated hydrocarbons are:

1. Methylene chloride (dichloromethane) - a colorless liquid with a mild sweet odor, used as a solvent in various industrial applications, including the production of pharmaceuticals and photographic films.
2. Chloroform - a heavy, volatile, and sweet-smelling liquid, used as an anesthetic in the past but now mainly used in chemical synthesis.
3. Carbon tetrachloride - a colorless, heavy, and nonflammable liquid with a mildly sweet odor, once widely used as a solvent and fire extinguishing agent but now largely phased out due to its ozone-depleting properties.
4. Vinyl chloride - a flammable, colorless gas, used primarily in the production of polyvinyl chloride (PVC) plastic and other synthetic materials.
5. Polychlorinated biphenyls (PCBs) - a group of highly stable and persistent organic compounds that were widely used as coolants and insulating fluids in electrical equipment but are now banned due to their toxicity and environmental persistence.

Exposure to chlorinated hydrocarbons can occur through inhalation, skin contact, or ingestion, depending on the specific compound and its physical state. Some chlorinated hydrocarbons have been linked to various health effects, including liver and kidney damage, neurological disorders, reproductive issues, and cancer. Therefore, proper handling, use, and disposal of these chemicals are essential to minimize potential health risks.

Dichlorodiphenyl dichloroethylene (DDE) is a chemical compound that is formed as a byproduct when dichlorodiphenyltrichloroethane (DDT) is metabolized or breaks down in the environment. DDE is an organochlorine pesticide and is similar in structure to DDT, with two phenyl rings and two chlorine atoms attached to a central ethylene molecule.

DDE is highly stable and does not break down easily in the environment, which means that it can persist for many years and accumulate in the food chain. It is lipophilic, meaning that it tends to accumulate in fatty tissues, and bioaccumulates in animals that are higher up in the food chain.

DDE has been shown to have toxic effects on both wildlife and humans. It can disrupt hormone systems, particularly those related to reproduction, and has been linked to reproductive problems in birds and other animals. In humans, exposure to DDE has been associated with increased risk of certain cancers, developmental delays in children, and other health problems.

DDE is no longer used as a pesticide in many countries, but it can still be found in the environment due to its persistence and ability to accumulate in the food chain. People can be exposed to DDE through contaminated food, water, or air, as well as through contact with soil or dust that contains DDE.

Dioxins are a group of chemically-related compounds that are primarily formed as unintended byproducts of various industrial, commercial, and domestic processes. They include polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and certain polychlorinated biphenyls (PCBs). Dioxins are highly persistent environmental pollutants that accumulate in the food chain, particularly in animal fat. Exposure to dioxins can cause a variety of adverse health effects, including developmental and reproductive problems, immune system damage, hormonal disruption, and cancer. The most toxic form of dioxin is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

Burkholderiaceae is a family of gram-negative, aerobic bacteria within the order Burkholderiales. This family includes several genera of medically important organisms, such as Burkholderia and Bordetella. Many species in this family are environmental organisms that can be found in soil, water, and associated with plants. However, some members of this family are also known to cause various types of human infections.

For example, Burkholderia cepacia complex (BCC) is a group of closely related species that can cause serious respiratory infections in people with weakened immune systems or chronic lung diseases such as cystic fibrosis. B. pseudomallei and B. mallei are two other species in this family that can cause severe and potentially life-threatening infections, including melioidosis and glanders, respectively.

Bordetella species, on the other hand, are known to cause respiratory tract infections in humans, such as whooping cough (caused by B. pertussis) and kennel cough (caused by B. bronchiseptica).

Overall, Burkholderiaceae is a diverse family of bacteria that includes both environmental organisms and important human pathogens. Accurate identification and characterization of these organisms is essential for appropriate diagnosis and treatment of infections caused by members of this family.

Dioxygenases are a class of enzymes that catalyze the incorporation of both atoms of molecular oxygen (O2) into their substrates. They are classified based on the type of reaction they catalyze and the number of iron atoms in their active site. The two main types of dioxygenases are:

1. Intradiol dioxygenases: These enzymes cleave an aromatic ring by inserting both atoms of O2 into a single bond between two carbon atoms, leading to the formation of an unsaturated diol (catechol) intermediate and the release of CO2. They contain a non-heme iron(III) center in their active site.

An example of intradiol dioxygenase is catechol 1,2-dioxygenase, which catalyzes the conversion of catechol to muconic acid.

2. Extradiol dioxygenases: These enzymes cleave an aromatic ring by inserting one atom of O2 at a position adjacent to the hydroxyl group and the other atom at a more distant position, leading to the formation of an unsaturated lactone or cyclic ether intermediate. They contain a non-heme iron(II) center in their active site.

An example of extradiol dioxygenase is homogentisate 1,2-dioxygenase, which catalyzes the conversion of homogentisate to maleylacetoacetate in the tyrosine degradation pathway.

Dioxygenases play important roles in various biological processes, including the metabolism of aromatic compounds, the biosynthesis of hormones and signaling molecules, and the detoxification of xenobiotics.

Benzofurans are a class of organic compounds that consist of a benzene ring fused to a furan ring. The furan ring is a five-membered aromatic heterocycle containing one oxygen atom and four carbon atoms. Benzofurans can be found in various natural and synthetic substances. Some benzofuran derivatives have biological activity and are used in medicinal chemistry, while others are used as flavorings or fragrances. However, some benzofuran compounds are also known to have psychoactive effects and can be abused as recreational drugs.

Flame retardants are chemical compounds that are added to materials, such as textiles, plastics, and foam furnishings, to reduce their flammability and prevent or slow down the spread of fire. They work by releasing non-flammable gases when exposed to heat, which helps to suppress the flames and prevent ignition. Flame retardants can be applied during the manufacturing process or added as a coating or treatment to existing materials. While flame retardants have been shown to save lives and property by preventing fires or reducing their severity, some types of flame retardants have been linked to health concerns, including endocrine disruption, neurodevelopmental toxicity, and cancer. Therefore, it is important to use flame retardants that are safe for human health and the environment.

Rhodococcus is a genus of gram-positive, aerobic, actinomycete bacteria that are widely distributed in the environment, including soil and water. Some species of Rhodococcus can cause opportunistic infections in humans and animals, particularly in individuals with weakened immune systems. These infections can affect various organs and tissues, such as the lungs, skin, and brain, and can range from mild to severe.

Rhodococcus species are known for their ability to degrade a wide variety of organic compounds, including hydrocarbons, making them important players in bioremediation processes. They also have complex cell walls that make them resistant to many antibiotics and disinfectants, which can complicate treatment of Rhodococcus infections.

I'm sorry for any confusion, but "soil pollutants" is not a term typically used in medical definitions. Soil pollution refers to the presence or accumulation of hazardous substances, chemicals, or other pollutants in soil that can have negative effects on plant life, human health, and the environment.

However, if you're asking about potential health effects of exposure to soil pollutants, it could include a variety of symptoms or diseases, depending on the specific pollutant. For example, exposure to lead-contaminated soil can lead to developmental delays in children, while exposure to certain pesticides or industrial chemicals can cause neurological problems, respiratory issues, and even cancer.

If you have more specific information about a particular substance or context, I may be able to provide a more precise answer.

Burkholderia is a genus of gram-negative, rod-shaped bacteria that are widely distributed in the environment, including soil, water, and associated with plants. Some species of Burkholderia are opportunistic pathogens, meaning they can cause infection in individuals with weakened immune systems or underlying medical conditions.

One of the most well-known species of Burkholderia is B. cepacia, which can cause respiratory infections in people with cystic fibrosis and chronic granulomatous disease. Other notable species include B. pseudomallei, the causative agent of melioidosis, a potentially serious infection that primarily affects the respiratory system; and B. mallei, which causes glanders, a rare but severe disease that can affect humans and animals.

Burkholderia species are known for their resistance to many antibiotics, making them difficult to treat in some cases. Proper identification of the specific Burkholderia species involved in an infection is important for determining the most appropriate treatment approach.

I'm sorry for any confusion, but "Great Lakes Region" is not a medical term. It generally refers to a geographical region in North America, comprising eight U.S. states and the Canadian province of Ontario around the Great Lakes. These are Michigan, Wisconsin, Minnesota, Illinois, Indiana, Ohio, Pennsylvania, and New York. If you have any medical terms you'd like defined, I'd be happy to help!

Food contamination is the presence of harmful microorganisms, chemicals, or foreign substances in food or water that can cause illness or injury to individuals who consume it. This can occur at any stage during production, processing, storage, or preparation of food, and can result from various sources such as:

1. Biological contamination: This includes the presence of harmful bacteria, viruses, parasites, or fungi that can cause foodborne illnesses. Examples include Salmonella, E. coli, Listeria, and norovirus.

2. Chemical contamination: This involves the introduction of hazardous chemicals into food, which may occur due to poor handling practices, improper storage, or exposure to environmental pollutants. Common sources of chemical contamination include pesticides, cleaning solvents, heavy metals, and natural toxins produced by certain plants or fungi.

3. Physical contamination: This refers to the presence of foreign objects in food, such as glass, plastic, hair, or insects, which can pose a choking hazard or introduce harmful substances into the body.

Preventing food contamination is crucial for ensuring food safety and protecting public health. Proper hygiene practices, temperature control, separation of raw and cooked foods, and regular inspections are essential measures to minimize the risk of food contamination.

Hexachlorobenzene (HCB) is not typically included in standard medical textbooks or resources as it's more of a environmental and industrial chemical. However, I can provide you with an definition from a toxicological perspective:

Hexachlorobenzene (C6Cl6) is an organic compound that consists of a benzene ring with six chlorine atoms attached to it. It is a persistent organic pollutant, which means it does not break down easily and can accumulate in the environment and living organisms. HCB has been used as a pesticide, fungicide, and chemical intermediate in various industrial processes. Exposure to this compound can lead to several health issues, including skin lesions, damage to the nervous system, and impaired immune function. It's also considered a possible human carcinogen by some agencies. Long-term environmental exposure to HCB is of particular concern due to its bioaccumulation in the food chain and potential adverse effects on human health and the environment.

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.

Halogenated diphenyl ethers are a group of chemical compounds that consist of two phenyl rings (aromatic hydrocarbon rings) linked by an ether group, with one or more halogens attached to the rings. The halogens can include chlorine, bromine, fluorine, or iodine atoms.

One of the most well-known halogenated diphenyl ethers is polychlorinated biphenyl (PCB), which was widely used in electrical equipment and industrial applications until it was banned due to its toxicity and environmental persistence. PCBs are known to have various adverse health effects, including cancer, reproductive disorders, and endocrine disruption.

Other halogenated diphenyl ethers, such as polybrominated diphenyl ethers (PBDEs), have also been used as flame retardants in consumer products, but their use has been restricted or phased out due to health and environmental concerns. Exposure to these compounds can occur through contaminated food, air, dust, and water, and may lead to similar health effects as PCB exposure.

Chemical water pollutants refer to harmful chemicals or substances that contaminate bodies of water, making them unsafe for human use and harmful to aquatic life. These pollutants can come from various sources, including industrial and agricultural runoff, sewage and wastewater, oil spills, and improper disposal of hazardous materials.

Examples of chemical water pollutants include heavy metals (such as lead, mercury, and cadmium), pesticides and herbicides, volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), and petroleum products. These chemicals can have toxic effects on aquatic organisms, disrupt ecosystems, and pose risks to human health through exposure or consumption.

Regulations and standards are in place to monitor and limit the levels of chemical pollutants in water sources, with the aim of protecting public health and the environment.

Environmental exposure refers to the contact of an individual with any chemical, physical, or biological agent in the environment that can cause a harmful effect on health. These exposures can occur through various pathways such as inhalation, ingestion, or skin contact. Examples of environmental exposures include air pollution, water contamination, occupational chemicals, and allergens. The duration and level of exposure, as well as the susceptibility of the individual, can all contribute to the risk of developing an adverse health effect.

"Body burden" is a term used in the field of environmental health to describe the total amount of a chemical or toxic substance that an individual has accumulated in their body tissues and fluids. It refers to the overall load or concentration of a particular chemical or contaminant that an organism is carrying, which can come from various sources such as air, water, food, and consumer products.

The term "body burden" highlights the idea that people can be exposed to harmful substances unknowingly and unintentionally, leading to potential health risks over time. Some factors that may influence body burden include the frequency and duration of exposure, the toxicity of the substance, and individual differences in metabolism, elimination, and susceptibility.

It is important to note that not all chemicals or substances found in the body are necessarily harmful, as some are essential for normal bodily functions. However, high levels of certain environmental contaminants can have adverse health effects, making it crucial to monitor and regulate exposure to these substances.

"Pseudomonas" is a genus of Gram-negative, rod-shaped bacteria that are widely found in soil, water, and plants. Some species of Pseudomonas can cause disease in animals and humans, with P. aeruginosa being the most clinically relevant as it's an opportunistic pathogen capable of causing various types of infections, particularly in individuals with weakened immune systems.

P. aeruginosa is known for its remarkable ability to resist many antibiotics and disinfectants, making infections caused by this bacterium difficult to treat. It can cause a range of healthcare-associated infections, such as pneumonia, bloodstream infections, urinary tract infections, and surgical site infections. In addition, it can also cause external ear infections and eye infections.

Prompt identification and appropriate antimicrobial therapy are crucial for managing Pseudomonas infections, although the increasing antibiotic resistance poses a significant challenge in treatment.

"Maternal exposure" is a medical term that refers to the contact or interaction of a pregnant woman with various environmental factors, such as chemicals, radiation, infectious agents, or physical environments, which could potentially have an impact on the developing fetus. This exposure can occur through different routes, including inhalation, ingestion, dermal contact, or even transplacentally. The effects of maternal exposure on the fetus can vary widely depending on the type, duration, and intensity of the exposure, as well as the stage of pregnancy at which it occurs. It is important to monitor and minimize maternal exposure to potentially harmful substances or environments during pregnancy to ensure the best possible outcomes for both the mother and developing fetus.

Chlorobenzoates are a group of chemical compounds that consist of a benzene ring substituted with one or more chlorine atoms and a carboxylate group. They are derivatives of benzoic acid, where one or more hydrogen atoms on the benzene ring have been replaced by chlorine atoms.

Chlorobenzoates can be found in various industrial applications, such as solvents, plasticizers, and pesticides. Some chlorobenzoates also have medical uses, for example, as antimicrobial agents or as intermediates in the synthesis of pharmaceuticals.

However, some chlorobenzoates can be toxic and harmful to the environment, so their use is regulated in many countries. It's important to handle and dispose of these substances properly to minimize potential health and environmental risks.

Gas Chromatography-Mass Spectrometry (GC-MS) is a powerful analytical technique that combines the separating power of gas chromatography with the identification capabilities of mass spectrometry. This method is used to separate, identify, and quantify different components in complex mixtures.

In GC-MS, the mixture is first vaporized and carried through a long, narrow column by an inert gas (carrier gas). The various components in the mixture interact differently with the stationary phase inside the column, leading to their separation based on their partition coefficients between the mobile and stationary phases. As each component elutes from the column, it is then introduced into the mass spectrometer for analysis.

The mass spectrometer ionizes the sample, breaks it down into smaller fragments, and measures the mass-to-charge ratio of these fragments. This information is used to generate a mass spectrum, which serves as a unique "fingerprint" for each compound. By comparing the generated mass spectra with reference libraries or known standards, analysts can identify and quantify the components present in the original mixture.

GC-MS has wide applications in various fields such as forensics, environmental analysis, drug testing, and research laboratories due to its high sensitivity, specificity, and ability to analyze volatile and semi-volatile compounds.

Aromatic hydrocarbons, also known as aromatic compounds or arenes, are a class of organic compounds characterized by a planar ring structure with delocalized electrons that give them unique chemical properties. The term "aromatic" was originally used to describe their distinctive odors, but it now refers to their characteristic molecular structure and stability.

Aromatic hydrocarbons contain one or more benzene rings, which are cyclic structures consisting of six carbon atoms arranged in a planar hexagonal shape. Each carbon atom in the benzene ring is bonded to two other carbon atoms and one hydrogen atom, forming alternating double and single bonds between the carbon atoms. However, the delocalized electrons in the benzene ring are evenly distributed around the ring, leading to a unique electronic structure that imparts stability and distinctive chemical properties to aromatic hydrocarbons.

Examples of aromatic hydrocarbons include benzene, toluene, xylene, and naphthalene. These compounds have important uses in industry, but they can also pose health risks if not handled properly. Exposure to high levels of aromatic hydrocarbons has been linked to various health effects, including cancer, neurological damage, and respiratory problems.

Tetrachlorodibenzodioxin (TCDD) is not a common medical term, but it is known in toxicology and environmental health. TCDD is the most toxic and studied compound among a group of chemicals known as dioxins.

Medical-related definition:

Tetrachlorodibenzodioxin (TCDD) is an unintended byproduct of various industrial processes, including waste incineration, chemical manufacturing, and pulp and paper bleaching. It is a highly persistent environmental pollutant that accumulates in the food chain, primarily in animal fat. Human exposure to TCDD mainly occurs through consumption of contaminated food, such as meat, dairy products, and fish. TCDD is a potent toxicant with various health effects, including immunotoxicity, reproductive and developmental toxicity, and carcinogenicity. The severity of these effects depends on the level and duration of exposure.

A Structure-Activity Relationship (SAR) in the context of medicinal chemistry and pharmacology refers to the relationship between the chemical structure of a drug or molecule and its biological activity or effect on a target protein, cell, or organism. SAR studies aim to identify patterns and correlations between structural features of a compound and its ability to interact with a specific biological target, leading to a desired therapeutic response or undesired side effects.

By analyzing the SAR, researchers can optimize the chemical structure of lead compounds to enhance their potency, selectivity, safety, and pharmacokinetic properties, ultimately guiding the design and development of novel drugs with improved efficacy and reduced toxicity.

Chlordane is a man-made chlorinated hydrocarbon compound that was widely used as a pesticide, particularly for termite control, from the 1940s until it was banned in the United States in 1988 due to its toxicity and persistence in the environment. It is a colorless or light brown liquid with a mild, aromatic odor.

Chlordane is an extremely toxic compound to insects and has been shown to have negative effects on human health as well. Exposure to chlordane can cause a range of adverse health effects, including neurological damage, liver toxicity, and an increased risk of cancer. It is classified as a probable human carcinogen by the International Agency for Research on Cancer (IARC) and the United States Environmental Protection Agency (EPA).

Chlordane is highly persistent in the environment and can accumulate in the food chain, posing a particular risk to wildlife and humans who consume contaminated food or water. It can also volatilize from soil and water into the air, where it can be transported long distances and contribute to air pollution. As a result, chlordane continues to pose a significant environmental and health hazard, even though its use has been banned for several decades.

Sulfur compounds refer to chemical substances that contain sulfur atoms. Sulfur can form bonds with many other elements, including carbon, hydrogen, oxygen, and nitrogen, among others. As a result, there is a wide variety of sulfur compounds with different structures and properties. Some common examples of sulfur compounds include hydrogen sulfide (H2S), sulfur dioxide (SO2), and sulfonic acids (R-SO3H).

In the medical field, sulfur compounds have various applications. For instance, some are used as drugs or drug precursors, while others are used in the production of medical devices or as disinfectants. Sulfur-containing amino acids, such as methionine and cysteine, are essential components of proteins and play crucial roles in many biological processes.

However, some sulfur compounds can also be harmful to human health. For example, exposure to high levels of hydrogen sulfide or sulfur dioxide can cause respiratory problems, while certain organosulfur compounds found in crude oil and coal tar have been linked to an increased risk of cancer. Therefore, it is essential to handle and dispose of sulfur compounds properly to minimize potential health hazards.

Pesticides are substances or mixtures of substances intended for preventing, destroying, or repelling pests. Pests can be insects, rodents, fungi, weeds, or other organisms that can cause damage to crops, animals, or humans and their living conditions. The term "pesticide" includes all of the following: insecticides, herbicides, fungicides, rodenticides, bactericides, and various other substances used to control pests.

It is important to note that while pesticides are designed to be toxic to the target pests, they can also pose risks to non-target organisms, including humans, if not used properly. Therefore, it is essential to follow all label instructions and safety precautions when handling and applying pesticides.

Iron-sulfur proteins are a group of metalloproteins that contain iron and sulfur atoms in their active centers. These clusters of iron and sulfur atoms, also known as iron-sulfur clusters, can exist in various forms, including Fe-S, 2Fe-2S, 3Fe-4S, and 4Fe-4S structures. The iron atoms are coordinated to the protein through cysteine residues, while the sulfur atoms can be in the form of sulfide (S2-) or sulfane (-S-).

These proteins play crucial roles in many biological processes, such as electron transfer, redox reactions, and enzyme catalysis. They are found in various organisms, from bacteria to humans, and are involved in a wide range of cellular functions, including energy metabolism, photosynthesis, nitrogen fixation, and DNA repair.

Iron-sulfur proteins can be classified into several categories based on their structure and function, such as ferredoxins, Rieske proteins, high-potential iron-sulfur proteins (HiPIPs), and radical SAM enzymes. Dysregulation or mutations in iron-sulfur protein genes have been linked to various human diseases, including neurodegenerative disorders, cancer, and mitochondrial disorders.

Hydroxylation is a biochemical process that involves the addition of a hydroxyl group (-OH) to a molecule, typically a steroid or xenobiotic compound. This process is primarily catalyzed by enzymes called hydroxylases, which are found in various tissues throughout the body.

In the context of medicine and biochemistry, hydroxylation can have several important functions:

1. Drug metabolism: Hydroxylation is a common way that the liver metabolizes drugs and other xenobiotic compounds. By adding a hydroxyl group to a drug molecule, it becomes more polar and water-soluble, which facilitates its excretion from the body.
2. Steroid hormone biosynthesis: Hydroxylation is an essential step in the biosynthesis of many steroid hormones, including cortisol, aldosterone, and the sex hormones estrogen and testosterone. These hormones are synthesized from cholesterol through a series of enzymatic reactions that involve hydroxylation at various steps.
3. Vitamin D activation: Hydroxylation is also necessary for the activation of vitamin D in the body. In order to become biologically active, vitamin D must undergo two successive hydroxylations, first in the liver and then in the kidneys.
4. Toxin degradation: Some toxic compounds can be rendered less harmful through hydroxylation. For example, phenol, a toxic compound found in cigarette smoke and some industrial chemicals, can be converted to a less toxic form through hydroxylation by enzymes in the liver.

Overall, hydroxylation is an important biochemical process that plays a critical role in various physiological functions, including drug metabolism, hormone biosynthesis, and toxin degradation.

Chromatography, gas (GC) is a type of chromatographic technique used to separate, identify, and analyze volatile compounds or vapors. In this method, the sample mixture is vaporized and carried through a column packed with a stationary phase by an inert gas (carrier gas). The components of the mixture get separated based on their partitioning between the mobile and stationary phases due to differences in their adsorption/desorption rates or solubility.

The separated components elute at different times, depending on their interaction with the stationary phase, which can be detected and quantified by various detection systems like flame ionization detector (FID), thermal conductivity detector (TCD), electron capture detector (ECD), or mass spectrometer (MS). Gas chromatography is widely used in fields such as chemistry, biochemistry, environmental science, forensics, and food analysis.

Volatile Organic Compounds (VOCs) are organic chemicals that have a low boiling point and easily evaporate at room temperature. They can be liquids or solids. VOCs include a variety of chemicals, such as benzene, toluene, xylene, and formaldehyde, which are found in many household products, including paints, paint strippers, and other solvents; cleaning supplies; pesticides; building materials and furnishings; office equipment such as copiers and printers, correction fluids and carbonless copy paper; and glues and adhesives.

VOCs can cause both short- and long-term health effects. Short-term exposure to high levels of VOCs can cause headaches, dizziness, visual disturbances, and memory problems. Long-term exposure can cause damage to the liver, kidneys, and central nervous system. Some VOCs are also suspected or known carcinogens.

It is important to properly use, store, and dispose of products that contain VOCs to minimize exposure. Increasing ventilation by opening windows and doors or using fans can also help reduce exposure to VOCs.

Halogenated hydrocarbons are organic compounds containing carbon (C), hydrogen (H), and one or more halogens, such as fluorine (F), chlorine (Cl), bromine (Br), or iodine (I). These compounds are formed when halogens replace one or more hydrogen atoms in a hydrocarbon molecule.

Halogenated hydrocarbons can be further categorized into two groups:

1. Halogenated aliphatic hydrocarbons: These include alkanes, alkenes, and alkynes with halogen atoms replacing hydrogen atoms. Examples include chloroform (trichloromethane, CHCl3), methylene chloride (dichloromethane, CH2Cl2), and trichloroethylene (C2HCl3).
2. Halogenated aromatic hydrocarbons: These consist of aromatic rings, such as benzene, with halogen atoms attached. Examples include chlorobenzene (C6H5Cl), bromobenzene (C6H5Br), and polyhalogenated biphenyls like polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs).

Halogenated hydrocarbons have various industrial applications, including use as solvents, refrigerants, fire extinguishing agents, and intermediates in chemical synthesis. However, some of these compounds can be toxic, environmentally persistent, and bioaccumulative, posing potential health and environmental risks.

Pesticide residues refer to the remaining pesticide chemicals, including their metabolites and degradation products, that are present in or on food commodities or environmental samples after a pesticide application has ended. These residues can result from agricultural use, such as spraying crops to control pests, or from non-agricultural uses, like treating buildings for termite control.

Regulatory agencies establish maximum residue limits (MRLs) to ensure that the levels of pesticide residues in food and feed are below those that may pose a risk to human health. Monitoring programs are in place to check compliance with these MRLs, and enforcement actions can be taken if violations occur.

It's important to note that not all pesticide residues are harmful, as some pesticides degrade into harmless compounds over time or leave behind residues below levels of concern for human health. However, long-term exposure to even low levels of certain pesticide residues may still pose a risk and should be avoided when possible.

Biotransformation is the metabolic modification of a chemical compound, typically a xenobiotic (a foreign chemical substance found within an living organism), by a biological system. This process often involves enzymatic conversion of the parent compound to one or more metabolites, which may be more or less active, toxic, or mutagenic than the original substance.

In the context of pharmacology and toxicology, biotransformation is an important aspect of drug metabolism and elimination from the body. The liver is the primary site of biotransformation, but other organs such as the kidneys, lungs, and gastrointestinal tract can also play a role.

Biotransformation can occur in two phases: phase I reactions involve functionalization of the parent compound through oxidation, reduction, or hydrolysis, while phase II reactions involve conjugation of the metabolite with endogenous molecules such as glucuronic acid, sulfate, or acetate to increase its water solubility and facilitate excretion.

I'm sorry for any confusion, but "Slovakia" is not a medical term. It is a country located in Central Europe. If you have any questions about medical terms or concepts, I would be happy to help answer those for you.

Environmental monitoring is the systematic and ongoing surveillance, measurement, and assessment of environmental parameters, pollutants, or other stressors in order to evaluate potential impacts on human health, ecological systems, or compliance with regulatory standards. This process typically involves collecting and analyzing data from various sources, such as air, water, soil, and biota, and using this information to inform decisions related to public health, environmental protection, and resource management.

In medical terms, environmental monitoring may refer specifically to the assessment of environmental factors that can impact human health, such as air quality, water contamination, or exposure to hazardous substances. This type of monitoring is often conducted in occupational settings, where workers may be exposed to potential health hazards, as well as in community-based settings, where environmental factors may contribute to public health issues. The goal of environmental monitoring in a medical context is to identify and mitigate potential health risks associated with environmental exposures, and to promote healthy and safe environments for individuals and communities.

Insecticides are substances or mixtures of substances intended for preventing, destroying, or mitigating any pest, including insects, arachnids, or other related pests. They can be chemical or biological agents that disrupt the growth, development, or behavior of these organisms, leading to their death or incapacitation. Insecticides are widely used in agriculture, public health, and residential settings for pest control. However, they must be used with caution due to potential risks to non-target organisms and the environment.

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.

Chlorine is a chemical element with the symbol Cl and atomic number 17. It is a member of the halogen group of elements and is the second-lightest halogen after fluorine. In its pure form, chlorine is a yellow-green gas under standard conditions.

Chlorine is an important chemical compound that has many uses in various industries, including water treatment, disinfection, and bleaching. It is also used in the production of a wide range of products, such as plastics, solvents, and pesticides.

In medicine, chlorine compounds are sometimes used for their antimicrobial properties. For example, sodium hypochlorite (bleach) is a common disinfectant used to clean surfaces and equipment in healthcare settings. Chlorhexidine is another chlorine compound that is widely used as an antiseptic and disinfectant in medical and dental procedures.

However, it's important to note that exposure to high concentrations of chlorine gas can be harmful to human health, causing respiratory irritation, coughing, and shortness of breath. Long-term exposure to chlorine can also lead to more serious health effects, such as damage to the lungs and other organs.

Stereoisomerism is a type of isomerism (structural arrangement of atoms) in which molecules have the same molecular formula and sequence of bonded atoms, but differ in the three-dimensional orientation of their atoms in space. This occurs when the molecule contains asymmetric carbon atoms or other rigid structures that prevent free rotation, leading to distinct spatial arrangements of groups of atoms around a central point. Stereoisomers can have different chemical and physical properties, such as optical activity, boiling points, and reactivities, due to differences in their shape and the way they interact with other molecules.

There are two main types of stereoisomerism: enantiomers (mirror-image isomers) and diastereomers (non-mirror-image isomers). Enantiomers are pairs of stereoisomers that are mirror images of each other, but cannot be superimposed on one another. Diastereomers, on the other hand, are non-mirror-image stereoisomers that have different physical and chemical properties.

Stereoisomerism is an important concept in chemistry and biology, as it can affect the biological activity of molecules, such as drugs and natural products. For example, some enantiomers of a drug may be active, while others are inactive or even toxic. Therefore, understanding stereoisomerism is crucial for designing and synthesizing effective and safe drugs.

Magnetic Resonance Spectroscopy (MRS) is a non-invasive diagnostic technique that provides information about the biochemical composition of tissues, including their metabolic state. It is often used in conjunction with Magnetic Resonance Imaging (MRI) to analyze various metabolites within body tissues, such as the brain, heart, liver, and muscles.

During MRS, a strong magnetic field, radio waves, and a computer are used to produce detailed images and data about the concentration of specific metabolites in the targeted tissue or organ. This technique can help detect abnormalities related to energy metabolism, neurotransmitter levels, pH balance, and other biochemical processes, which can be useful for diagnosing and monitoring various medical conditions, including cancer, neurological disorders, and metabolic diseases.

There are different types of MRS, such as Proton (^1^H) MRS, Phosphorus-31 (^31^P) MRS, and Carbon-13 (^13^C) MRS, each focusing on specific elements or metabolites within the body. The choice of MRS technique depends on the clinical question being addressed and the type of information needed for diagnosis or monitoring purposes.

Cytochrome P-450 CYP1A1 is an enzyme that is part of the cytochrome P450 family, which are a group of enzymes involved in the metabolism of drugs and other xenobiotics (foreign substances) in the body. Specifically, CYP1A1 is found primarily in the liver and lungs and plays a role in the metabolism of polycyclic aromatic hydrocarbons (PAHs), which are chemicals found in tobacco smoke and are produced by the burning of fossil fuels and other organic materials.

CYP1A1 also has the ability to activate certain procarcinogens, which are substances that can be converted into cancer-causing agents (carcinogens) within the body. Therefore, variations in the CYP1A1 gene may influence an individual's susceptibility to cancer and other diseases.

The term "P-450" refers to the fact that these enzymes absorb light at a wavelength of 450 nanometers when they are combined with carbon monoxide, giving them a characteristic pink color. The "CYP" stands for "cytochrome P," and the number and letter designations (e.g., 1A1) indicate the specific enzyme within the family.

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.

Human milk, also known as breast milk, is the nutrient-rich fluid produced by the human female mammary glands to feed and nourish their infants. It is the natural and species-specific first food for human babies, providing all the necessary nutrients in a form that is easily digestible and absorbed. Human milk contains a balance of proteins, carbohydrates, fats, vitamins, minerals, and other bioactive components that support the growth, development, and immunity of newborns and young infants. Its composition changes over time, adapting to meet the changing needs of the growing infant.

Endocrine disruptors are defined as exogenous (external) substances or mixtures that interfere with the way hormones work in the body, leading to negative health effects. They can mimic, block, or alter the normal synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body responsible for maintaining homeostasis, reproduction, development, and/or behavior.

Endocrine disruptors can be found in various sources, including industrial chemicals, pesticides, pharmaceuticals, and personal care products. They have been linked to a range of health problems, such as cancer, reproductive issues, developmental disorders, neurological impairments, and immune system dysfunction.

Examples of endocrine disruptors include bisphenol A (BPA), phthalates, dioxins, polychlorinated biphenyls (PCBs), perfluoroalkyl substances (PFAS), and certain pesticides like dichlorodiphenyltrichloroethane (DDT) and vinclozolin.

It is important to note that endocrine disruptors can have effects at very low doses, and their impact may depend on the timing of exposure, particularly during critical windows of development such as fetal growth and early childhood.

DDT (dichlorodiphenyltrichloroethane) is a synthetic insecticide that was widely used in the mid-20th century to control agricultural pests and vector-borne diseases such as malaria. It belongs to a class of chemicals called organochlorines, which are known for their persistence in the environment and potential for bioaccumulation in the food chain.

DDT was first synthesized in 1874, but its insecticidal properties were not discovered until 1939. Its use as an insecticide became widespread during World War II, when it was used to control typhus and malaria-carrying lice and mosquitoes among troops. After the war, DDT was widely adopted for agricultural and public health purposes.

However, concerns about the environmental and human health effects of DDT led to its ban or severe restriction in many countries starting in the 1970s. The United States banned the use of DDT for most purposes in 1972, and the Stockholm Convention on Persistent Organic Pollutants (POPs) prohibited its production and use globally in 2004, except in cases where there is a risk of vector-borne diseases.

DDT has been linked to several health problems, including reproductive effects, developmental toxicity, neurotoxicity, and endocrine disruption. It is also highly persistent in the environment, with a half-life of up to 15 years in soil and up to 30 years in water. This means that DDT can accumulate in the food chain, posing risks to wildlife and humans who consume contaminated food or water.

In summary, DDT is a synthetic insecticide that was widely used in the mid-20th century but has been banned or restricted in many countries due to its environmental and health effects. It belongs to a class of chemicals called organochlorines, which are known for their persistence in the environment and potential for bioaccumulation in the food chain. DDT has been linked to several health problems, including reproductive effects, developmental toxicity, neurotoxicity, and endocrine disruption.

Medical definitions typically focus on the relevance of a term to medicine or healthcare, so here's a medical perspective on polycyclic compounds:

Polycyclic compounds are organic substances that contain two or more chemical rings in their structure. While not all polycyclic compounds are relevant to medicine, some can have significant medical implications. For instance, polycyclic aromatic hydrocarbons (PAHs) are a type of polycyclic compound that can be found in tobacco smoke and certain types of air pollution. PAHs have been linked to an increased risk of cancer, particularly lung cancer, due to their ability to damage DNA.

Another example is the class of drugs called steroids, which include hormones like cortisol and sex hormones like testosterone and estrogen. These compounds are polycyclic because they contain several interconnected rings in their structure. Steroid medications are used to treat a variety of medical conditions, including inflammation, asthma, and Addison's disease.

In summary, while not all polycyclic compounds are relevant to medicine, some can have important medical implications, either as harmful environmental pollutants or as useful therapeutic agents.

I'm sorry for any confusion, but "Michigan" is not a medical term or concept. It is a geographical location, referring to the state of Michigan in the United States. If you have any questions related to medical topics, I would be happy to try and help answer those for you!

"Prenatal exposure delayed effects" refer to the adverse health outcomes or symptoms that become apparent in an individual during their development or later in life, which are caused by exposure to certain environmental factors or substances while they were still in the womb. These effects may not be immediately observable at birth and can take weeks, months, years, or even decades to manifest. They can result from maternal exposure to various agents such as infectious diseases, medications, illicit drugs, tobacco smoke, alcohol, or environmental pollutants during pregnancy. The delayed effects can impact multiple organ systems and may include physical, cognitive, behavioral, and developmental abnormalities. It is important to note that the risk and severity of these effects can depend on several factors, including the timing, duration, and intensity of the exposure, as well as the individual's genetic susceptibility.

Industrial fungicides are antimicrobial agents used to prevent, destroy, or inhibit the growth of fungi and their spores in industrial settings. These can include uses in manufacturing processes, packaging materials, textiles, paints, and other industrial products. They work by interfering with the cellular structure or metabolic processes of fungi, thereby preventing their growth or reproduction. Examples of industrial fungicides include:

* Sodium hypochlorite (bleach)
* Formaldehyde
* Glutaraldehyde
* Quaternary ammonium compounds
* Peracetic acid
* Chlorhexidine
* Iodophors

It's important to note that some of these fungicides can be harmful or toxic to humans and other organisms, so they must be used with caution and in accordance with safety guidelines.

"Pseudomonas pseudoalcaligenes" is a gram-negative, rod-shaped bacterium that is widely found in various environments such as soil, water, and clinical samples. It is a close relative to the Pseudomonas genus but can be differentiated by its biochemical characteristics. This bacterium is generally considered to be non-pathogenic to humans, but it has been occasionally associated with infections in immunocompromised individuals or those with underlying medical conditions. It is known for its ability to degrade a wide range of organic compounds and can be used in bioremediation applications.

I'm sorry for any confusion, but "Phenyl Ethers" is not a recognized medical term. Phenyl ethers are a class of organic compounds consisting of an ether with a phenyl group as one of the components. They are widely used in industry and research, including as solvents, intermediates in chemical synthesis, and pharmaceuticals.

However, if you have any concerns about exposure to certain chemicals or their effects on health, it would be best to consult with a medical professional who can provide advice based on your specific situation and symptoms.

Inhibitory Concentration 50 (IC50) is a measure used in pharmacology, toxicology, and virology to describe the potency of a drug or chemical compound. It refers to the concentration needed to reduce the biological or biochemical activity of a given substance by half. Specifically, it is most commonly used in reference to the inhibition of an enzyme or receptor.

In the context of infectious diseases, IC50 values are often used to compare the effectiveness of antiviral drugs against a particular virus. A lower IC50 value indicates that less of the drug is needed to achieve the desired effect, suggesting greater potency and potentially fewer side effects. Conversely, a higher IC50 value suggests that more of the drug is required to achieve the same effect, indicating lower potency.

It's important to note that IC50 values can vary depending on the specific assay or experimental conditions used, so they should be interpreted with caution and in conjunction with other measures of drug efficacy.

Pentachlorophenol is not primarily a medical term, but rather a chemical compound with some uses and applications in the medical field. Medically, it's important to understand what pentachlorophenol is due to its potential health implications.

Pentachlorophenol (PCP) is an organochlorine compound that has been widely used as a pesticide, wood preservative, and disinfectant. Its chemical formula is C6HCl5O. It is a white crystalline solid with a distinct, somewhat unpleasant odor. In the environment, pentachlorophenol can be found in soil, water, and air as well as in various organisms, including humans.

Pentachlorophenol has been associated with several potential health risks. It is classified as a probable human carcinogen by the International Agency for Research on Cancer (IARC) and as a possible human carcinogen by the United States Environmental Protection Agency (EPA). Exposure to pentachlorophenol can occur through inhalation, skin contact, or ingestion. Potential health effects include irritation of the skin, eyes, and respiratory tract; damage to the liver and kidneys; neurological issues; and reproductive problems.

In a medical context, pentachlorophenol might be relevant in cases where individuals have been exposed to this compound through occupational or environmental sources. Medical professionals may need to assess potential health risks, diagnose related health issues, and provide appropriate treatment.

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.

'Armoracia' is the genus name for a type of plant commonly known as horseradish. It belongs to the family Brassicaceae, which also includes vegetables such as broccoli, cabbage, and mustard greens. The root of the horseradish plant is used as a spice or condiment due to its pungent flavor, which is caused by the release of volatile oils when the root is grated or crushed.

Horseradish has been used in traditional medicine for various purposes, such as treating respiratory infections and promoting digestion. However, it is important to note that while some studies suggest potential health benefits of horseradish, more research is needed to confirm its effectiveness and safety. As with any medication or supplement, it is recommended to consult with a healthcare professional before using horseradish for medicinal purposes.

I apologize, but there seems to be a misunderstanding. "Soil microbiology" is not a medical term; rather, it is a branch of microbiology that deals with the study of microorganisms in soil. It involves understanding the diversity, ecology, and biochemistry of bacteria, fungi, algae, protozoa, and other microscopic life forms found in soil. This field has applications in agriculture, environmental science, and waste management but is not directly related to medical definitions or human health.

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.

Preclinical drug evaluation refers to a series of laboratory tests and studies conducted to determine the safety and effectiveness of a new drug before it is tested in humans. These studies typically involve experiments on cells and animals to evaluate the pharmacological properties, toxicity, and potential interactions with other substances. The goal of preclinical evaluation is to establish a reasonable level of safety and understanding of how the drug works, which helps inform the design and conduct of subsequent clinical trials in humans. It's important to note that while preclinical studies provide valuable information, they may not always predict how a drug will behave in human subjects.

Pregnancy is a physiological state or condition where a fertilized egg (zygote) successfully implants and grows in the uterus of a woman, leading to the development of an embryo and finally a fetus. This process typically spans approximately 40 weeks, divided into three trimesters, and culminates in childbirth. Throughout this period, numerous hormonal and physical changes occur to support the growing offspring, including uterine enlargement, breast development, and various maternal adaptations to ensure the fetus's optimal growth and well-being.

Methylmercury compounds are organic forms of mercury, created when methyl groups (CH3) bind to a mercury ion (Hg+). These compounds can be highly toxic and bioaccumulate in living organisms, including humans. They are primarily formed in the environment through the action of bacteria on inorganic mercury, but can also be produced synthetically.

Methylmercury is particularly dangerous because it easily passes through biological membranes, allowing it to enter the brain and other tissues where it can cause significant damage. Exposure to high levels of methylmercury can lead to neurological problems, developmental issues in children, and even death. It's commonly found in contaminated fish and seafood, making these a significant source of human exposure.

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.

Chlorobenzenes are a group of chemical compounds that consist of a benzene ring (a cyclic structure with six carbon atoms in a hexagonal arrangement) substituted with one or more chlorine atoms. They have the general formula C6H5Clx, where x represents the number of chlorine atoms attached to the benzene ring.

Chlorobenzenes are widely used as industrial solvents, fumigants, and intermediates in the production of other chemicals. Some common examples of chlorobenzenes include monochlorobenzene (C6H5Cl), dichlorobenzenes (C6H4Cl2), trichlorobenzenes (C6H3Cl3), and tetrachlorobenzenes (C6H2Cl4).

Exposure to chlorobenzenes can occur through inhalation, skin contact, or ingestion. They are known to be toxic and can cause a range of health effects, including irritation of the eyes, skin, and respiratory tract, headaches, dizziness, nausea, and vomiting. Long-term exposure has been linked to liver and kidney damage, neurological effects, and an increased risk of cancer.

It is important to handle chlorobenzenes with care and follow appropriate safety precautions to minimize exposure. If you suspect that you have been exposed to chlorobenzenes, seek medical attention immediately.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Dichlorodiphenyldichloroethane (DDT) is a synthetic insecticide that was widely used in the 20th century to control agricultural pests and vector-borne diseases such as malaria. It is a colorless, odorless crystalline solid with a weak sweetish taste. DDT has high toxicity to many insects, but relatively low toxicity to mammals and birds. However, its persistence in the environment and bioaccumulation in the food chain have raised significant environmental and health concerns.

DDT was first synthesized in 1874, but its insecticidal properties were not discovered until 1939. During World War II, it was used extensively to control typhus and malaria-carrying mosquitoes, saving countless lives. After the war, DDT became a popular agricultural pesticide, leading to widespread use in agriculture and public health programs.

However, in the 1960s, studies began to reveal the negative impacts of DDT on wildlife, particularly birds. Rachel Carson's book "Silent Spring" (1962) brought these issues to public attention and helped launch the modern environmental movement. Research showed that DDT caused thinning of eggshells in birds, leading to reproductive failure and population declines.

In 1972, the United States banned the use of DDT for most purposes due to its environmental persistence, bioaccumulation, and toxicity to wildlife. Many other countries followed suit, and international agreements were established to limit its production and use. However, DDT is still used in some countries to control vector-borne diseases such as malaria, despite concerns about its long-term impacts on human health and the environment.

DDT has been linked to several potential health effects in humans, including cancer, reproductive problems, and developmental issues. However, the evidence for these risks is not conclusive, and more research is needed to fully understand the potential health impacts of DDT exposure.

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.

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.

Hydrolases are a class of enzymes that help facilitate the breakdown of various types of chemical bonds through a process called hydrolysis, which involves the addition of water. These enzymes catalyze the cleavage of bonds in substrates by adding a molecule of water, leading to the formation of two or more smaller molecules.

Hydrolases play a crucial role in many biological processes, including digestion, metabolism, and detoxification. They can act on a wide range of substrates, such as proteins, lipids, carbohydrates, and nucleic acids, breaking them down into smaller units that can be more easily absorbed or utilized by the body.

Examples of hydrolases include:

1. Proteases: enzymes that break down proteins into smaller peptides or amino acids.
2. Lipases: enzymes that hydrolyze lipids, such as triglycerides, into fatty acids and glycerol.
3. Amylases: enzymes that break down complex carbohydrates, like starches, into simpler sugars, such as glucose.
4. Nucleases: enzymes that cleave nucleic acids, such as DNA or RNA, into smaller nucleotides or oligonucleotides.
5. Phosphatases: enzymes that remove phosphate groups from various substrates, including proteins and lipids.
6. Esterases: enzymes that hydrolyze ester bonds in a variety of substrates, such as those found in some drugs or neurotransmitters.

Hydrolases are essential for maintaining proper cellular function and homeostasis, and their dysregulation can contribute to various diseases and disorders.

Heterocyclic compounds are organic compounds that contain at least one atom within the ring structure, other than carbon, such as nitrogen, oxygen, sulfur or phosphorus. These compounds make up a large class of naturally occurring and synthetic materials, including many drugs, pigments, vitamins, and antibiotics. The presence of the heteroatom in the ring can have significant effects on the physical and chemical properties of the compound, such as its reactivity, stability, and bonding characteristics. Examples of heterocyclic compounds include pyridine, pyrimidine, and furan.

Toluene is not a medical condition or disease, but it is a chemical compound that is widely used in various industrial and commercial applications. Medically, toluene can be relevant as a substance of abuse due to its intoxicating effects when inhaled or sniffed. It is a colorless liquid with a distinctive sweet aroma, and it is a common solvent found in many products such as paint thinners, adhesives, and rubber cement.

In the context of medical toxicology, toluene exposure can lead to various health issues, including neurological damage, cognitive impairment, memory loss, nausea, vomiting, and hearing and vision problems. Chronic exposure to toluene can also cause significant harm to the developing fetus during pregnancy, leading to developmental delays, behavioral problems, and physical abnormalities.

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds characterized by the presence of two or more fused benzene rings. They are called "polycyclic" because they contain multiple cyclic structures, and "aromatic" because these structures contain alternating double bonds that give them distinctive chemical properties and a characteristic smell.

PAHs can be produced from both natural and anthropogenic sources. Natural sources include wildfires, volcanic eruptions, and the decomposition of organic matter. Anthropogenic sources include the incomplete combustion of fossil fuels, such as coal, oil, and gasoline, as well as tobacco smoke, grilled foods, and certain industrial processes.

PAHs are known to be environmental pollutants and can have harmful effects on human health. They have been linked to an increased risk of cancer, particularly lung, skin, and bladder cancers, as well as reproductive and developmental toxicity. PAHs can also cause skin irritation, respiratory problems, and damage to the immune system.

PAHs are found in a variety of environmental media, including air, water, soil, and food. They can accumulate in the food chain, particularly in fatty tissues, and have been detected in a wide range of foods, including meat, fish, dairy products, and vegetables. Exposure to PAHs can occur through inhalation, ingestion, or skin contact.

It is important to limit exposure to PAHs by avoiding tobacco smoke, reducing consumption of grilled and smoked foods, using ventilation when cooking, and following safety guidelines when working with industrial processes that produce PAHs.

Benzene derivatives are chemical compounds that are derived from benzene, which is a simple aromatic hydrocarbon with the molecular formula C6H6. Benzene has a planar, hexagonal ring structure, and its derivatives are formed by replacing one or more of the hydrogen atoms in the benzene molecule with other functional groups.

Benzene derivatives have a wide range of applications in various industries, including pharmaceuticals, dyes, plastics, and explosives. Some common examples of benzene derivatives include toluene, xylene, phenol, aniline, and nitrobenzene. These compounds can have different physical and chemical properties depending on the nature and position of the substituents attached to the benzene ring.

It is important to note that some benzene derivatives are known to be toxic or carcinogenic, and their production, use, and disposal must be carefully regulated to ensure safety and protect public health.

Furans are not a medical term, but a class of organic compounds that contain a four-membered ring with four atoms, usually carbon and oxygen. They can be found in some foods and have been used in the production of certain industrial chemicals. Some furan derivatives have been identified as potentially toxic or carcinogenic, but the effects of exposure to these substances depend on various factors such as the level and duration of exposure.

In a medical context, furans may be mentioned in relation to environmental exposures, food safety, or occupational health. For example, some studies have suggested that high levels of exposure to certain furan compounds may increase the risk of liver damage or cancer. However, more research is needed to fully understand the potential health effects of these substances.

It's worth noting that furans are not a specific medical condition or diagnosis, but rather a class of chemical compounds with potential health implications. If you have concerns about exposure to furans or other environmental chemicals, it's best to consult with a healthcare professional for personalized advice and recommendations.

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.

Enzyme induction is a process by which the activity or expression of an enzyme is increased in response to some stimulus, such as a drug, hormone, or other environmental factor. This can occur through several mechanisms, including increasing the transcription of the enzyme's gene, stabilizing the mRNA that encodes the enzyme, or increasing the translation of the mRNA into protein.

In some cases, enzyme induction can be a beneficial process, such as when it helps the body to metabolize and clear drugs more quickly. However, in other cases, enzyme induction can have negative consequences, such as when it leads to the increased metabolism of important endogenous compounds or the activation of harmful procarcinogens.

Enzyme induction is an important concept in pharmacology and toxicology, as it can affect the efficacy and safety of drugs and other xenobiotics. It is also relevant to the study of drug interactions, as the induction of one enzyme by a drug can lead to altered metabolism and effects of another drug that is metabolized by the same enzyme.

Safrole is defined medically as a phenolic compound that occurs naturally in certain essential oils, such as sassafras oil. It has been used traditionally as a flavoring agent and in folk medicine for its alleged medicinal properties. However, safrole has been found to have toxic and carcinogenic effects, and its use is now restricted in many countries.

In a more specific chemical definition, safrole is a phenylpropanoid compound with the molecular formula C10H12O3. It is a colorless to pale yellow oily liquid that has a sweet, woody, and spicy odor. Safrole can be found in various plant species, including sassafras, betel nut, and camphor wood.

It's important to note that safrole is considered a controlled substance in many jurisdictions due to its potential use as a precursor in the illegal synthesis of certain drugs, such as MDMA (ecstasy).

A Small Molecule Library is a collection of a large number of chemically synthesized, low molecular weight (typically under 900 daltons) compounds, which are used in drug discovery and development research. These libraries contain diverse structures and chemical properties, allowing researchers to screen them against specific targets, such as proteins or genes, to identify potential lead compounds that can be further optimized for therapeutic use. The use of small molecule libraries enables high-throughput screening, which is a rapid and efficient method to identify potential drug candidates.

I'm sorry for any confusion, but "geologic sediments" is not a term used in medical definitions. Geological sediments are deposits of material that accumulate over time, usually in layers, as a result of natural geological processes such as weathering, erosion, and deposition. These sediments can eventually become rock formations and provide important clues about the Earth's history, including information about past climates, environments, and life on Earth.

*Comamonas testosteroni* is a species of gram-negative, rod-shaped bacteria that is commonly found in the environment, such as in soil and water. It is capable of degrading various organic compounds, including steroids like testosterone, which is how it gets its name. This bacterium is not typically associated with human disease, but there have been rare cases of infections reported in people with weakened immune systems.

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.

"Pseudomonas putida" is a species of gram-negative, rod-shaped bacteria that is commonly found in soil and water environments. It is a non-pathogenic, opportunistic microorganism that is known for its versatile metabolism and ability to degrade various organic compounds. This bacterium has been widely studied for its potential applications in bioremediation and industrial biotechnology due to its ability to break down pollutants such as toluene, xylene, and other aromatic hydrocarbons. It is also known for its resistance to heavy metals and antibiotics, making it a valuable tool in the study of bacterial survival mechanisms and potential applications in bioremediation and waste treatment.

The endocrine system is a complex network of glands and organs that produce, store, and secrete hormones. It plays a crucial role in regulating various functions and processes in the body, including metabolism, growth and development, tissue function, sexual function, reproduction, sleep, and mood.

The major endocrine glands include:

1. Pituitary gland: located at the base of the brain, it is often referred to as the "master gland" because it controls other glands' functions. It produces and releases several hormones that regulate growth, development, and reproduction.
2. Thyroid gland: located in the neck, it produces hormones that regulate metabolism, growth, and development.
3. Parathyroid glands: located near the thyroid gland, they produce parathyroid hormone, which regulates calcium levels in the blood.
4. Adrenal glands: located on top of the kidneys, they produce hormones that regulate stress response, metabolism, and blood pressure.
5. Pancreas: located in the abdomen, it produces hormones such as insulin and glucagon that regulate blood sugar levels.
6. Sex glands (ovaries and testes): they produce sex hormones such as estrogen, progesterone, and testosterone that regulate sexual development and reproduction.
7. Pineal gland: located in the brain, it produces melatonin, a hormone that regulates sleep-wake cycles.

The endocrine system works closely with the nervous system to maintain homeostasis or balance in the body's internal environment. Hormones are chemical messengers that travel through the bloodstream to target cells or organs, where they bind to specific receptors and elicit a response. Disorders of the endocrine system can result from overproduction or underproduction of hormones, leading to various health problems such as diabetes, thyroid disorders, growth disorders, and sexual dysfunction.

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

Bacteria are single-celled microorganisms that are among the earliest known life forms on Earth. They are typically characterized as having a cell wall and no membrane-bound organelles. The majority of bacteria have a prokaryotic organization, meaning they lack a nucleus and other membrane-bound organelles.

Bacteria exist in diverse environments and can be found in every habitat on Earth, including soil, water, and the bodies of plants and animals. Some bacteria are beneficial to their hosts, while others can cause disease. Beneficial bacteria play important roles in processes such as digestion, nitrogen fixation, and biogeochemical cycling.

Bacteria reproduce asexually through binary fission or budding, and some species can also exchange genetic material through conjugation. They have a wide range of metabolic capabilities, with many using organic compounds as their source of energy, while others are capable of photosynthesis or chemosynthesis.

Bacteria are highly adaptable and can evolve rapidly in response to environmental changes. This has led to the development of antibiotic resistance in some species, which poses a significant public health challenge. Understanding the biology and behavior of bacteria is essential for developing strategies to prevent and treat bacterial infections and diseases.

Chloroflexi is a phylum of bacteria that contains gram-negative, filamentous, and often thermophilic or piezophilic species. These bacteria are characterized by their unique flexirubin-type pigments and the presence of chlorosomes, which are specialized structures for light-harvesting in some photosynthetic members of the phylum. Chloroflexi bacteria are widely distributed in various environments, including soil, freshwater, marine habitats, and hot springs. Some species are capable of anaerobic respiration or fermentation, while others perform oxygenic photosynthesis. The phylum was previously known as green non-sulfur bacteria or flexibacteria.

Volatilization, in the context of pharmacology and medicine, refers to the process by which a substance (usually a medication or drug) transforms into a vapor state at room temperature or upon heating. This change in physical state allows the substance to evaporate and be transferred into the air, potentially leading to inhalation exposure.

In some medical applications, volatilization is used intentionally, such as with essential oils for aromatherapy or topical treatments that utilize a vapor action. However, it can also pose concerns when volatile substances are unintentionally released into the air, potentially leading to indoor air quality issues or exposure risks.

It's important to note that in clinical settings, volatilization is not typically used as a route of administration for medications, as other methods such as oral, intravenous, or inhalation via nebulizers are more common and controlled.

Organotin compounds are a group of chemical compounds that contain carbon, hydrogen, and tin. They have the general formula RnSnX4-n, where R represents an organic group (such as a methyl or phenyl group), X represents a halogen or other substituent, and n can range from 1 to 3. These compounds are used in a variety of applications, including as biocides, PVC stabilizers, and catalysts. However, they have also been found to have toxic effects on the immune system, endocrine system, and nervous system, and some organotin compounds have been restricted or banned for use in certain products due to these concerns.

Catechols are a type of chemical compound that contain a benzene ring with two hydroxyl groups (-OH) attached to it in the ortho position. The term "catechol" is often used interchangeably with "ortho-dihydroxybenzene." Catechols are important in biology because they are produced through the metabolism of certain amino acids, such as phenylalanine and tyrosine, and are involved in the synthesis of various neurotransmitters and hormones. They also have antioxidant properties and can act as reducing agents. In chemistry, catechols can undergo various reactions, such as oxidation and polymerization, to form other classes of compounds.

I'm sorry for any confusion, but the term "preconception injuries" is not typically used in medical literature or clinical settings. The term "preconception" generally refers to the time before pregnancy, and it is often used in the context of preconception care, which includes actions taken to identify and address potential health risks before a woman becomes pregnant.

Injuries are typically not considered "preconception," as they are acute events that occur at a specific point in time rather than being a chronic condition that exists before pregnancy. If you have any further questions or if there is another term you'd like me to define, please let me know!

Chlorine compounds refer to chemical substances that contain chlorine (Cl), which is a member of the halogen group in the periodic table. Chlorine is a highly reactive element that readily forms compounds with many other elements and molecules.

Chlorine compounds can be found in various forms, including inorganic and organic compounds. Inorganic chlorine compounds include salts of hydrochloric acid, such as sodium chloride (table salt), and chlorides of metals, such as copper chloride and silver chloride. Other inorganic chlorine compounds include chlorine gas (Cl2), hypochlorous acid (HClO), and chlorine dioxide (ClO2).

Organic chlorine compounds are those that contain carbon atoms bonded to chlorine atoms. Examples of organic chlorine compounds include chlorinated solvents, such as trichloroethylene and perchloroethylene, and pesticides, such as DDT and lindane.

Chlorine compounds have a wide range of uses in various industries, including water treatment, disinfection, pharmaceuticals, agrochemicals, and manufacturing. However, some chlorine compounds can be harmful or toxic to humans and the environment, particularly if they are released into the air, water, or soil in large quantities. Therefore, it is essential to handle and dispose of chlorine compounds properly to minimize potential health and environmental risks.

Sphingomonas is a genus of gram-negative, aerobic bacteria that are widely distributed in the environment. They are known for their ability to degrade various organic compounds and are often found in water, soil, and air samples. The cells of Sphingomonas species are typically straight or slightly curved rods, and they do not form spores.

One distinctive feature of Sphingomonas species is the presence of a unique lipid called sphingolipid in their cell membranes. This lipid contains a long-chain base called sphingosine, which is not found in the cell membranes of other gram-negative bacteria. The genus Sphingomonas includes several species that have been associated with human infections, particularly in immunocompromised individuals. These infections can include bacteremia, pneumonia, and urinary tract infections. However, Sphingomonas species are generally considered to be of low virulence and are not typically regarded as major pathogens.

Electricity is not a medical term, but rather a fundamental aspect of physics and science. It refers to the form of energy resulting from the existence of charged particles such as electrons or protons, either statically as an accumulation of charge or dynamically as a current.

However, in the context of medical procedures and treatments, electricity is often used to stimulate nerves or muscles, destroy tissue through processes like electrocoagulation, or generate images of internal structures using methods like electrocardiography (ECG) or electroencephalography (EEG). In these cases, a clear medical definition would be:

The use of electric currents or fields in medical procedures for therapeutic or diagnostic purposes.

Aniline compounds, also known as aromatic amines, are organic compounds that contain a benzene ring substituted with an amino group (-NH2). Aniline itself is the simplest and most common aniline compound, with the formula C6H5NH2.

Aniline compounds are important in the chemical industry and are used in the synthesis of a wide range of products, including dyes, pharmaceuticals, and rubber chemicals. They can be produced by reducing nitrobenzene or by directly substituting ammonia onto benzene in a process called amination.

It is important to note that aniline compounds are toxic and can cause serious health effects, including damage to the liver, kidneys, and central nervous system. They can also be absorbed through the skin and are known to have carcinogenic properties. Therefore, appropriate safety measures must be taken when handling aniline compounds.

Microsomes, liver refers to a subcellular fraction of liver cells (hepatocytes) that are obtained during tissue homogenization and subsequent centrifugation. These microsomal fractions are rich in membranous structures known as the endoplasmic reticulum (ER), particularly the rough ER. They are involved in various important cellular processes, most notably the metabolism of xenobiotics (foreign substances) including drugs, toxins, and carcinogens.

The liver microsomes contain a variety of enzymes, such as cytochrome P450 monooxygenases, that are crucial for phase I drug metabolism. These enzymes help in the oxidation, reduction, or hydrolysis of xenobiotics, making them more water-soluble and facilitating their excretion from the body. Additionally, liver microsomes also host other enzymes involved in phase II conjugation reactions, where the metabolites from phase I are further modified by adding polar molecules like glucuronic acid, sulfate, or acetyl groups.

In summary, liver microsomes are a subcellular fraction of liver cells that play a significant role in the metabolism and detoxification of xenobiotics, contributing to the overall protection and maintenance of cellular homeostasis within the body.

Environmental pollution is the introduction or presence of harmful substances, energies, or objects in the environment that can cause adverse effects on living organisms and ecosystems. These pollutants can be in the form of chemical, physical, or biological agents that contaminate air, water, soil, or noise levels, exceeding safe limits established by environmental regulations.

Examples of environmental pollution include:

1. Air pollution: The presence of harmful substances such as particulate matter, sulfur dioxide, nitrogen oxides, and volatile organic compounds (VOCs) in the air that can cause respiratory and other health problems.
2. Water pollution: Contamination of water sources with chemicals, heavy metals, pathogens, or other pollutants that can harm aquatic life and make the water unsafe for human consumption or recreational use.
3. Soil pollution: The presence of harmful substances such as heavy metals, pesticides, and industrial waste in soil that can reduce soil fertility, contaminate crops, and pose a risk to human health.
4. Noise pollution: Excessive noise levels from transportation, industrial activities, or other sources that can cause stress, sleep disturbances, and hearing loss in humans and animals.
5. Light pollution: The excessive use of artificial light that can disrupt ecosystems, affect human circadian rhythms, and contribute to energy waste.

Environmental pollution is a significant global health issue that requires urgent attention and action from governments, industries, and individuals to reduce pollutant emissions, promote sustainable practices, and protect the environment for future generations.

"Spiro compounds" are not specifically classified as medical terms, but they are a concept in organic chemistry. However, I can provide a general definition:

Spiro compounds are a type of organic compound that contains two or more rings, which share a single common atom, known as the "spiro center." The name "spiro" comes from the Greek word for "spiral" or "coiled," reflecting the three-dimensional structure of these molecules.

The unique feature of spiro compounds is that they have at least one spiro atom, typically carbon, which is bonded to four other atoms, two of which belong to each ring. This arrangement creates a specific geometry where the rings are positioned at right angles to each other, giving spiro compounds distinctive structural and chemical properties.

While not directly related to medical terminology, understanding spiro compounds can be essential in medicinal chemistry and pharmaceutical research since these molecules often exhibit unique biological activities due to their intricate structures.

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

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

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

The Cytochrome P-450 (CYP450) enzyme system is a group of enzymes found primarily in the liver, but also in other organs such as the intestines, lungs, and skin. These enzymes play a crucial role in the metabolism and biotransformation of various substances, including drugs, environmental toxins, and endogenous compounds like hormones and fatty acids.

The name "Cytochrome P-450" refers to the unique property of these enzymes to bind to carbon monoxide (CO) and form a complex that absorbs light at a wavelength of 450 nm, which can be detected spectrophotometrically.

The CYP450 enzyme system is involved in Phase I metabolism of xenobiotics, where it catalyzes oxidation reactions such as hydroxylation, dealkylation, and epoxidation. These reactions introduce functional groups into the substrate molecule, which can then undergo further modifications by other enzymes during Phase II metabolism.

There are several families and subfamilies of CYP450 enzymes, each with distinct substrate specificities and functions. Some of the most important CYP450 enzymes include:

1. CYP3A4: This is the most abundant CYP450 enzyme in the human liver and is involved in the metabolism of approximately 50% of all drugs. It also metabolizes various endogenous compounds like steroids, bile acids, and vitamin D.
2. CYP2D6: This enzyme is responsible for the metabolism of many psychotropic drugs, including antidepressants, antipsychotics, and beta-blockers. It also metabolizes some endogenous compounds like dopamine and serotonin.
3. CYP2C9: This enzyme plays a significant role in the metabolism of warfarin, phenytoin, and nonsteroidal anti-inflammatory drugs (NSAIDs).
4. CYP2C19: This enzyme is involved in the metabolism of proton pump inhibitors, antidepressants, and clopidogrel.
5. CYP2E1: This enzyme metabolizes various xenobiotics like alcohol, acetaminophen, and carbon tetrachloride, as well as some endogenous compounds like fatty acids and prostaglandins.

Genetic polymorphisms in CYP450 enzymes can significantly affect drug metabolism and response, leading to interindividual variability in drug efficacy and toxicity. Understanding the role of CYP450 enzymes in drug metabolism is crucial for optimizing pharmacotherapy and minimizing adverse effects.

Xylenes are aromatic hydrocarbons that are often used as solvents in the industrial field. They are composed of two benzene rings with methyl side groups (-CH3) and can be found as a mixture of isomers: ortho-xylene, meta-xylene, and para-xylene.

In a medical context, xylenes may be relevant due to their potential for exposure in occupational settings or through environmental contamination. Short-term exposure to high levels of xylenes can cause irritation of the eyes, nose, throat, and lungs, as well as symptoms such as headache, dizziness, and nausea. Long-term exposure has been linked to neurological effects, including memory impairment, hearing loss, and changes in behavior and mood.

It is worth noting that xylenes are not typically considered a direct medical diagnosis, but rather a potential exposure hazard or environmental contaminant that may have health impacts.

Nitrogen compounds are chemical substances that contain nitrogen, which is a non-metal in group 15 of the periodic table. Nitrogen forms compounds with many other elements due to its ability to form multiple bonds, including covalent bonds with hydrogen, oxygen, carbon, sulfur, and halogens.

Nitrogen can exist in several oxidation states, ranging from -3 to +5, which leads to a wide variety of nitrogen compounds with different properties and uses. Some common examples of nitrogen compounds include:

* Ammonia (NH3), a colorless gas with a pungent odor, used in fertilizers, cleaning products, and refrigeration systems.
* Nitric acid (HNO3), a strong mineral acid used in the production of explosives, dyes, and fertilizers.
* Ammonium nitrate (NH4NO3), a white crystalline solid used as a fertilizer and explosive ingredient.
* Hydrazine (N2H4), a colorless liquid with a strong odor, used as a rocket fuel and reducing agent.
* Nitrous oxide (N2O), a colorless gas used as an anesthetic and laughing gas in dental procedures.

Nitrogen compounds have many important applications in various industries, such as agriculture, pharmaceuticals, chemicals, and energy production. However, some nitrogen compounds can also be harmful or toxic to humans and the environment if not handled properly.

'Alcaligenes' is a genus of gram-negative, aerobic bacteria that are commonly found in soil, water, and the respiratory and intestinal tracts of animals. These bacteria are capable of using a variety of organic compounds as their sole source of carbon and energy. Some species of Alcaligenes have been known to cause opportunistic infections in humans, particularly in individuals with weakened immune systems. However, they are not considered major human pathogens.

The name 'Alcaligenes' comes from the Latin word "alcali," meaning "alkali," and the Greek word "genos," meaning "kind" or "race." This is because many species of Alcaligenes can grow in alkaline environments with a pH above 7.

It's worth noting that while Alcaligenes species are not typically harmful to healthy individuals, they may be resistant to certain antibiotics and can cause serious infections in people with compromised immune systems. Therefore, it is important for healthcare professionals to consider the possibility of Alcaligenes infection in patients who are at risk and to choose appropriate antibiotic therapy based on laboratory testing.

Halogenation is a general term used in chemistry and biochemistry, including medical contexts, to refer to the process of introducing a halogen atom into a molecule. Halogens are a group of non-metallic elements that include fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).

In medical terms, halogenation is often discussed in the context of pharmaceuticals or biological molecules. For example, the halogenation of aromatic compounds can increase their lipophilicity, which can affect their ability to cross cell membranes and interact with biological targets. This can be useful in drug design and development, as modifying a lead compound's halogenation pattern may enhance its therapeutic potential or alter its pharmacokinetic properties.

However, it is essential to note that halogenation can also impact the safety and toxicity profiles of compounds. Therefore, understanding the effects of halogenation on a molecule's structure and function is crucial in drug design and development processes.

Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.

Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.

Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.

Toxaphene is not typically defined in a medical context as it is not a medication or a condition. However, it is a chemical compound that has been used as a pesticide and has been banned in many countries due to its toxicity and environmental persistence.

Medically, toxaphene exposure can lead to various health issues, including skin and eye irritation, respiratory problems, neurological symptoms, and potential cancer risk. Therefore, it is sometimes mentioned in medical literature in the context of occupational or environmental health.

Aryl hydrocarbon receptors (AhRs) are a type of intracellular receptor that play a crucial role in the response to environmental contaminants and other xenobiotic compounds. They are primarily found in the cytoplasm of cells, where they bind to aromatic hydrocarbons, including polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), which are common environmental pollutants.

Once activated by ligand binding, AhRs translocate to the nucleus, where they dimerize with the AhR nuclear translocator (ARNT) protein and bind to specific DNA sequences called xenobiotic response elements (XREs). This complex then regulates the expression of a variety of genes involved in xenobiotic metabolism, including those encoding cytochrome P450 enzymes.

In addition to their role in xenobiotic metabolism, AhRs have been implicated in various physiological processes, such as immune response, cell differentiation, and development. Dysregulation of AhR signaling has been associated with the pathogenesis of several diseases, including cancer, autoimmune disorders, and neurodevelopmental disorders.

Therefore, understanding the mechanisms of AhR activation and regulation is essential for developing strategies to prevent or treat environmental toxicant-induced diseases and other conditions linked to AhR dysfunction.

I believe there may be a misunderstanding in your question. The term "fishes" is not typically used in a medical context. "Fish" or "fishes" refers to any aquatic organism belonging to the taxonomic class Actinopterygii (bony fish), Chondrichthyes (sharks and rays), or Agnatha (jawless fish).

However, if you are referring to a condition related to fish or consuming fish, there is a medical issue called scombroid fish poisoning. It's a foodborne illness caused by eating spoiled or improperly stored fish from the Scombridae family, which includes tuna, mackerel, and bonito, among others. The bacteria present in these fish can produce histamine, which can cause symptoms like skin flushing, headache, diarrhea, and itchy rash. But again, this is not related to the term "fishes" itself but rather a condition associated with consuming certain types of fish.

Nikethamide, also known as Coramine or Levaminopeptide, is a stimulant drug that was used in the past to treat hypotension and to improve breathing in people with respiratory depression. It works by increasing the body's oxygen consumption and stimulating the respiratory system.

Nikethamide is no longer commonly used in clinical practice due to its narrow therapeutic index, potential for abuse, and availability of safer and more effective alternatives. It is classified as a controlled substance in many countries and its use is restricted to certain research or veterinary applications.

Chemical water pollution is the contamination of water bodies (such as lakes, rivers, oceans, and groundwater) with harmful chemicals or substances that negatively impact water quality and pose a threat to human health, aquatic life, and the environment. These chemical pollutants can come from various sources, including industrial and agricultural activities, waste disposal, oil spills, and chemical accidents. Examples of chemical pollutants include heavy metals (such as mercury, lead, and cadmium), pesticides, volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), and other hazardous substances. These chemicals can have toxic, carcinogenic, mutagenic, or teratogenic effects on living organisms and can disrupt ecosystems, leading to decreased biodiversity and impaired ecological functions.

Molecular conformation, also known as spatial arrangement or configuration, refers to the specific three-dimensional shape and orientation of atoms that make up a molecule. It describes the precise manner in which bonds between atoms are arranged around a molecular framework, taking into account factors such as bond lengths, bond angles, and torsional angles.

Conformational isomers, or conformers, are different spatial arrangements of the same molecule that can interconvert without breaking chemical bonds. These isomers may have varying energies, stability, and reactivity, which can significantly impact a molecule's biological activity and function. Understanding molecular conformation is crucial in fields such as drug design, where small changes in conformation can lead to substantial differences in how a drug interacts with its target.

"Drug design" is the process of creating and developing a new medication or therapeutic agent to treat or prevent a specific disease or condition. It involves identifying potential targets within the body, such as proteins or enzymes that are involved in the disease process, and then designing small molecules or biologics that can interact with these targets to produce a desired effect.

The drug design process typically involves several stages, including:

1. Target identification: Researchers identify a specific molecular target that is involved in the disease process.
2. Lead identification: Using computational methods and high-throughput screening techniques, researchers identify small molecules or biologics that can interact with the target.
3. Lead optimization: Researchers modify the chemical structure of the lead compound to improve its ability to interact with the target, as well as its safety and pharmacokinetic properties.
4. Preclinical testing: The optimized lead compound is tested in vitro (in a test tube or petri dish) and in vivo (in animals) to evaluate its safety and efficacy.
5. Clinical trials: If the preclinical testing is successful, the drug moves on to clinical trials in humans to further evaluate its safety and efficacy.

The ultimate goal of drug design is to create a new medication that is safe, effective, and can be used to improve the lives of patients with a specific disease or condition.

Nitroso compounds are a class of chemical compounds that contain a nitroso functional group, which is composed of a nitrogen atom bonded to an oxygen atom with a single covalent bond. The general formula for nitroso compounds is R-N=O, where R represents an organic group such as an alkyl or aryl group.

Nitroso compounds are known to be reactive and can form under various physiological conditions. They have been implicated in the formation of carcinogenic substances and have been linked to DNA damage and mutations. In the medical field, nitroso compounds have been studied for their potential use as therapeutic agents, particularly in the treatment of cancer and cardiovascular diseases. However, their use is limited due to their potential toxicity and carcinogenicity.

It's worth noting that exposure to high levels of nitroso compounds can be harmful to human health, and may cause respiratory, dermal, and ocular irritation, as well as potential genotoxic effects. Therefore, handling and storage of nitroso compounds should be done with caution, following appropriate safety guidelines.

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.

Organometallic compounds are a type of chemical compound that contain at least one metal-carbon bond. This means that the metal is directly attached to carbon atom(s) from an organic molecule. These compounds can be synthesized through various methods, and they have found widespread use in industrial and medicinal applications, including catalysis, polymerization, and pharmaceuticals.

It's worth noting that while organometallic compounds contain metal-carbon bonds, not all compounds with metal-carbon bonds are considered organometallic. For example, in classical inorganic chemistry, simple salts of metal carbonyls (M(CO)n) are not typically classified as organometallic, but rather as metal carbonyl complexes. The distinction between these classes of compounds can sometimes be subtle and is a matter of ongoing debate among chemists.

Mass spectrometry (MS) is an analytical technique used to identify and quantify the chemical components of a mixture or compound. It works by ionizing the sample, generating charged molecules or fragments, and then measuring their mass-to-charge ratio in a vacuum. The resulting mass spectrum provides information about the molecular weight and structure of the analytes, allowing for identification and characterization.

In simpler terms, mass spectrometry is a method used to determine what chemicals are present in a sample and in what quantities, by converting the chemicals into ions, measuring their masses, and generating a spectrum that shows the relative abundances of each ion type.

Organoselenium compounds are organic chemicals that contain selenium, a naturally occurring non-metal element, in their structure. Selenium is chemically related to sulfur and can replace it in many organic molecules. Organoselenium compounds have been studied for their potential therapeutic benefits, including antioxidant, anti-cancer, and anti-inflammatory effects. They are also used as catalysts in chemical reactions. These compounds contain at least one carbon atom bonded to selenium, which can take the form of a variety of functional groups such as selenoethers, selenols, and selenoesters.

Drug screening assays for antitumor agents are laboratory tests used to identify and evaluate the effectiveness of potential drugs or compounds that can inhibit the growth of tumor cells or induce their death. These assays are typically performed in vitro (in a test tube or petri dish) using cell cultures of various types of cancer cells.

The assays measure different parameters such as cell viability, proliferation, apoptosis (programmed cell death), and cytotoxicity to determine the ability of the drug to kill or inhibit the growth of tumor cells. The results of these assays can help researchers identify promising antitumor agents that can be further developed for clinical use in cancer treatment.

There are different types of drug screening assays for antitumor agents, including high-throughput screening (HTS) assays, which allow for the rapid and automated testing of a large number of compounds against various cancer cell lines. Other types of assays include phenotypic screening assays, target-based screening assays, and functional screening assays, each with its own advantages and limitations.

Overall, drug screening assays for antitumor agents play a critical role in the development of new cancer therapies by providing valuable information on the activity and safety of potential drugs, helping to identify effective treatments and reduce the time and cost associated with bringing new drugs to market.

Maternal-fetal exchange, also known as maternal-fetal transport or placental transfer, refers to the physiological process by which various substances are exchanged between the mother and fetus through the placenta. This exchange includes the transfer of oxygen and nutrients from the mother's bloodstream to the fetal bloodstream, as well as the removal of waste products and carbon dioxide from the fetal bloodstream to the mother's bloodstream.

The process occurs via passive diffusion, facilitated diffusion, and active transport mechanisms across the placental barrier, which is composed of fetal capillary endothelial cells, the extracellular matrix, and the syncytiotrophoblast layer of the placenta. The maternal-fetal exchange is crucial for the growth, development, and survival of the fetus throughout pregnancy.

Quantitative Structure-Activity Relationship (QSAR) is a method used in toxicology and medicinal chemistry that attempts to establish mathematical relationships between the chemical structure of a compound and its biological activity. QSAR models are developed using statistical methods to analyze a set of compounds with known biological activities and their structural properties, which are represented as numerical or categorical descriptors. These models can then be used to predict the biological activity of new, structurally similar compounds.

QSAR models have been widely used in drug discovery and development, as well as in chemical risk assessment, to predict the potential toxicity of chemicals based on their structural properties. The accuracy and reliability of QSAR predictions depend on various factors, including the quality and diversity of the data used to develop the models, the choice of descriptors and statistical methods, and the applicability domain of the models.

In summary, QSAR is a quantitative method that uses mathematical relationships between chemical structure and biological activity to predict the potential toxicity or efficacy of new compounds based on their structural properties.

Bromine compounds refer to chemical substances that contain bromine, a halogen element with the atomic number 35 and symbol Br. Bromine is a volatile, reddish-brown liquid at room temperature that evaporates easily into a red-brown gas with a strong, chlorine-like odor.

Bromine compounds can be formed when bromine combines with other elements or compounds. These compounds have various properties and uses depending on the other elements or groups involved. Some common examples of bromine compounds include:

1. Bromides: These are salts of hydrobromic acid, which contains bromide ions (Br-). They are commonly used as sedatives, anticonvulsants, and in photography.
2. Organobromines: These are organic compounds that contain bromine atoms. They have various uses, including as flame retardants, fumigants, and intermediates in the production of other chemicals.
3. Bromates: These are oxides of bromine that contain the bromate ion (BrO3-). They are used as oxidizing agents in water treatment and bleaching.
4. Bromine pentafluoride (BrF5): This is a highly reactive and corrosive compound that is used as a fluorinating agent in chemical reactions.
5. Bromine trifluoride (BrF3): This is another reactive and corrosive compound that is used as a fluorinating agent, particularly in the production of uranium hexafluoride for nuclear reactors.

It's important to note that some bromine compounds can be toxic, corrosive, or environmentally harmful, so they must be handled with care and disposed of properly.

Phenanthrenes are not typically defined in a medical context, but they are a class of organic compounds that have a polycyclic aromatic hydrocarbon structure consisting of three benzene rings fused together. They can be found in some natural products and have been studied for their potential pharmacological properties. Some phenanthrenes have shown anti-inflammatory, antioxidant, and cytotoxic activities, among others. However, more research is needed to fully understand their therapeutic potential and safety profile.

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.

Organophosphorus compounds are a class of chemical substances that contain phosphorus bonded to organic compounds. They are used in various applications, including as plasticizers, flame retardants, pesticides (insecticides, herbicides, and nerve gases), and solvents. In medicine, they are also used in the treatment of certain conditions such as glaucoma. However, organophosphorus compounds can be toxic to humans and animals, particularly those that affect the nervous system by inhibiting acetylcholinesterase, an enzyme that breaks down the neurotransmitter acetylcholine. Exposure to these compounds can cause symptoms such as nausea, vomiting, muscle weakness, and in severe cases, respiratory failure and death.

Oxidoreductases are a class of enzymes that catalyze oxidation-reduction reactions, which involve the transfer of electrons from one molecule (the reductant) to another (the oxidant). These enzymes play a crucial role in various biological processes, including energy production, metabolism, and detoxification.

The oxidoreductase-catalyzed reaction typically involves the donation of electrons from a reducing agent (donor) to an oxidizing agent (acceptor), often through the transfer of hydrogen atoms or hydride ions. The enzyme itself does not undergo any permanent chemical change during this process, but rather acts as a catalyst to lower the activation energy required for the reaction to occur.

Oxidoreductases are classified and named based on the type of electron donor or acceptor involved in the reaction. For example, oxidoreductases that act on the CH-OH group of donors are called dehydrogenases, while those that act on the aldehyde or ketone groups are called oxidases. Other examples include reductases, peroxidases, and catalases.

Understanding the function and regulation of oxidoreductases is important for understanding various physiological processes and developing therapeutic strategies for diseases associated with impaired redox homeostasis, such as cancer, neurodegenerative disorders, and cardiovascular disease.

Chemical processes refer to the various interactions and transformations that occur at the molecular or atomic level among chemicals, substances, or compounds. These processes involve changes in the structure, composition, energy state, or properties of the involved materials. They can be either spontaneous or induced and are governed by the laws of chemistry.

Some common examples of chemical processes include:

1. Chemical reactions: The transformation of one or more substances into different substances through a series of chemical interactions. These reactions might involve the breaking and forming of chemical bonds, resulting in new compounds with distinct properties.
2. Oxidation-reduction (redox) reactions: A specific type of chemical reaction where electrons are transferred between molecules or atoms, leading to changes in their oxidation states. These reactions often involve the transfer of oxygen or hydrogen atoms and play a crucial role in various biological and industrial processes.
3. Acid-base reactions: Chemical interactions between acids and bases, characterized by the transfer of a proton (H+) from an acid to a base. These reactions result in the formation of new compounds called salts and water.
4. Precipitation reactions: The formation of an insoluble solid (a precipitate) when two solutions are mixed together, often due to the creation of a new compound that cannot remain dissolved in the solvent.
5. Complexation: The formation of a complex between a central atom or ion and one or more ligands through coordinate covalent bonds. This process can lead to changes in the physical and chemical properties of both the central atom/ion and the ligand(s).
6. Electrolysis: A chemical process driven by an external electrical current, which induces chemical reactions at the electrodes immersed in a conducting solution (electrolyte). This process is used to produce various chemicals, such as hydrogen, chlorine, and sodium hydroxide.
7. Catalysis: The acceleration of a chemical reaction by a substance called a catalyst, which remains unchanged at the end of the reaction. Catalysts work by lowering the activation energy required for the reaction to occur, thereby increasing the rate of the process without being consumed in it.

Understanding chemical processes is essential for various fields, including chemistry, biology, medicine, materials science, and engineering, as they form the basis for numerous natural phenomena and technological applications.

Azo compounds are organic compounds characterized by the presence of one or more azo groups (-N=N-) in their molecular structure. The term "azo" is derived from the Greek word "azō," meaning "to boil" or "to sparkle," which refers to the brightly colored nature of many azo compounds.

These compounds are synthesized by the reaction between aromatic amines and nitrous acid or its derivatives, resulting in the formation of diazonium salts, which then react with another aromatic compound containing an active methylene group to form azo compounds.

Azo compounds have diverse applications across various industries, including dyes, pigments, pharmaceuticals, and agrochemicals. They are known for their vibrant colors, making them widely used as colorants in textiles, leather, paper, and food products. In addition, some azo compounds exhibit unique chemical properties, such as solubility, stability, and reactivity, which make them valuable intermediates in the synthesis of various organic compounds.

However, certain azo compounds have been found to pose health risks due to their potential carcinogenicity and mutagenicity. As a result, regulations have been imposed on their use in consumer products, particularly those intended for oral consumption or direct skin contact.

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.

Aniline hydroxylase is an enzyme that is involved in the metabolism of aromatic compounds, including aniline and other related substances. The enzyme catalyzes the addition of a hydroxyl group (-OH) to the aromatic ring of these compounds, which helps to make them more water-soluble and facilitates their excretion from the body.

Aniline hydroxylase is found in various tissues throughout the body, including the liver, lung, and kidney. It is a member of the cytochrome P450 family of enzymes, which are known for their role in drug metabolism and other xenobiotic-metabolizing reactions.

It's important to note that exposure to aniline and its derivatives can be harmful and may cause various health effects, including damage to the liver and other organs. Therefore, it is essential to handle these substances with care and follow appropriate safety precautions.

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.

Naphthalene is not typically referred to as a medical term, but it is a chemical compound with the formula C10H8. It is a white crystalline solid that is aromatic and volatile, and it is known for its distinctive mothball smell. In a medical context, naphthalene is primarily relevant as a potential toxin or irritant.

Naphthalene can be found in some chemical products, such as mothballs and toilet deodorant blocks. Exposure to high levels of naphthalene can cause symptoms such as nausea, vomiting, diarrhea, and headaches. Long-term exposure has been linked to anemia and damage to the liver and nervous system.

In addition, naphthalene is a known environmental pollutant that can be found in air, water, and soil. It is produced by the combustion of fossil fuels and is also released from some industrial processes. Naphthalene has been shown to have toxic effects on aquatic life and may pose a risk to human health if exposure levels are high enough.

I'm sorry for any confusion, but "New York" is not a medical term or concept. New York refers to a state in the United States, as well as its largest city. If you have any questions about medical terminology or concepts, I would be happy to help with those!

Water pollutants refer to any substances or materials that contaminate water sources and make them unsafe or unsuitable for use. These pollutants can include a wide range of chemicals, microorganisms, and physical particles that can have harmful effects on human health, aquatic life, and the environment as a whole. Examples of water pollutants include heavy metals like lead and mercury, industrial chemicals such as polychlorinated biphenyls (PCBs) and dioxins, agricultural runoff containing pesticides and fertilizers, sewage and wastewater, oil spills, and microplastics. Exposure to water pollutants can cause a variety of health problems, ranging from minor irritations to serious illnesses or even death in extreme cases. Additionally, water pollution can have significant impacts on the environment, including harming or killing aquatic life, disrupting ecosystems, and reducing biodiversity.

"Salix" is the genus name for a group of plants commonly known as willows. These are deciduous trees and shrubs that belong to the family Salicaceae. While "Salix" is not a medical term itself, certain species of willow have been used in medicine for their medicinal properties.

For instance, the bark of white willow (Salix alba) contains salicin, which has anti-inflammatory and analgesic effects similar to aspirin. The use of willow bark extract as a natural pain reliever and fever reducer dates back thousands of years in various traditional medicine systems.

However, it's important to note that the modern medical definition of "salicylate" refers to a group of compounds that includes both naturally occurring substances like salicin found in willow bark and synthetic derivatives such as aspirin (acetylsalicylic acid). These compounds share similar therapeutic properties and are used to treat pain, inflammation, and fever.

Benzopyrene hydroxylase is an enzyme that is involved in the metabolism and detoxification of polycyclic aromatic hydrocarbons (PAHs), which are a group of environmental pollutants found in cigarette smoke, air pollution, and charred or overcooked foods. Benzopyrene hydroxylase is primarily found in the liver and is responsible for adding a hydroxyl group to benzopyrene, a type of PAH, making it more water-soluble and easier to excrete from the body. This enzyme plays an important role in the body's defense against the harmful effects of PAHs.

In the context of medicine, "chemistry" often refers to the field of study concerned with the properties, composition, and structure of elements and compounds, as well as their reactions with one another. It is a fundamental science that underlies much of modern medicine, including pharmacology (the study of drugs), toxicology (the study of poisons), and biochemistry (the study of the chemical processes that occur within living organisms).

In addition to its role as a basic science, chemistry is also used in medical testing and diagnosis. For example, clinical chemistry involves the analysis of bodily fluids such as blood and urine to detect and measure various substances, such as glucose, cholesterol, and electrolytes, that can provide important information about a person's health status.

Overall, chemistry plays a critical role in understanding the mechanisms of diseases, developing new treatments, and improving diagnostic tests and techniques.

A bacterial gene is a segment of DNA (or RNA in some viruses) that contains the genetic information necessary for the synthesis of a functional bacterial protein or RNA molecule. These genes are responsible for encoding various characteristics and functions of bacteria such as metabolism, reproduction, and resistance to antibiotics. They can be transmitted between bacteria through horizontal gene transfer mechanisms like conjugation, transformation, and transduction. Bacterial genes are often organized into operons, which are clusters of genes that are transcribed together as a single mRNA molecule.

It's important to note that the term "bacterial gene" is used to describe genetic elements found in bacteria, but not all genetic elements in bacteria are considered genes. For example, some DNA sequences may not encode functional products and are therefore not considered genes. Additionally, some bacterial genes may be plasmid-borne or phage-borne, rather than being located on the bacterial chromosome.

Mutagens are physical or chemical agents that can cause permanent changes in the structure of genetic material, including DNA and chromosomes, leading to mutations. These mutations can be passed down to future generations and may increase the risk of cancer and other diseases. Examples of mutagens include ultraviolet (UV) radiation, tobacco smoke, and certain chemicals found in industrial settings. It is important to note that not all mutations are harmful, but some can have negative effects on health and development.

Epoxy compounds, also known as epoxy resins, are a type of thermosetting polymer characterized by the presence of epoxide groups in their molecular structure. An epoxide group is a chemical functional group consisting of an oxygen atom double-bonded to a carbon atom, which is itself bonded to another carbon atom.

Epoxy compounds are typically produced by reacting a mixture of epichlorohydrin and bisphenol-A or other similar chemicals under specific conditions. The resulting product is a two-part system consisting of a resin and a hardener, which must be mixed together before use.

Once the two parts are combined, a chemical reaction takes place that causes the mixture to cure or harden into a solid material. This curing process can be accelerated by heat, and once fully cured, epoxy compounds form a strong, durable, and chemically resistant material that is widely used in various industrial and commercial applications.

In the medical field, epoxy compounds are sometimes used as dental restorative materials or as adhesives for bonding medical devices or prosthetics. However, it's important to note that some people may have allergic reactions to certain components of epoxy compounds, so their use must be carefully evaluated and monitored in a medical context.

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"New biphenyl compounds with DNA strand-scission activity from Clusia paralicola". Journal of Natural Products. 62 (11): 1484- ...
The compound is an biphenyl amide derived inhibitor of succinate dehydrogenase. Inhibition of succinate dehydrogenase, the ... The first compound in this class was carboxin, which had a narrow spectrum of useful biological activity, mainly on ... The compound is very persistent in field conditions and its environmental fate and consequent ecotoxicology have been reviewed ... The compound lacks full control of important cereal diseases, especially septoria leaf blotch Zymoseptoria tritici, which has ...
S. paucimobilis is able to degrade lignin-related biphenyl chemical compounds. Yabuuchi, Eiko; Yano, Ikuya; Oyaizu, Hiroshi; ... "Cloning of a Sphingomonas paucimobilis SYK-6 gene encoding a novel oxygenase that cleaves lignin-related biphenyl and ...
Masuda, Y (2003). "Health Effect of Polychlorinated Biphenyls and Related Compounds". J Health Sci. 49 (5): 333-336. doi: ... Dioxins and polychlorinated biphenyls (PCBs) are two groups of predominately man-made toxic chemicals which, when consumed, ... It was announced that "dioxins & dioxin like PCBs", a group of highly toxic synthetic halogenated organic compounds, had been ... 2006). Health Risks from Dioxin and Related Compounds: Evaluation of the EPA Reassessment (Report in Brief) (PDF). The National ...
Steric effects from the biphenyl substituents also contribute to the compound's stability. BDPA and closely related compounds ... The compound was first synthesized by C. Frederick Koelsch while he was a postdoctoral fellow at Harvard University in the ... He attempted to publish a paper describing the compound, but the paper was rejected on the grounds that the described ... BDPA is an unusually stable radical compound due to the extent to which its electrons are delocalized through resonance ...
Novel biphenyl tricyclic quinazoline compounds and aryloxy quinolone derivatives are multiple kinase inhibitors. They are less ... Another compound with sunitinib heterocyclic moiety and a pyrrole side chain has very good VEGFR-2 potency, with an IC50 of 65 ... Compounds with thieno [3,2-b] pyridine urea moiety are inhibitory for VEGF receptor signaling and HGF receptor signaling. HGF ... For R2, two groups can show this effect on the compound, an ether group on one, and on the other a chloride group. When ...
Polychlorinated biphenyls (PCBs) are a class of chlorinated compounds used as industrial coolants and lubricants. PCBs are ... Fürst P (October 2006). "Dioxins, polychlorinated biphenyls and other organohalogen compounds in human milk. Levels, ... Endocrine disrupting compounds encompass a variety of chemical classes, including drugs, pesticides, compounds used in the ... "Biomonitoring and Elimination of Perfluorinated Compounds and Polychlorinated Biphenyls through Perspiration: Blood, Urine, and ...
Brominated dioxins and biphenyls have similar properties, but they have been studied much less. Many natural compounds have ... Fürst P (October 2006). "Dioxins, polychlorinated biphenyls and other organohalogen compounds in human milk. Levels, ... Polychlorinated biphenyls (PCBs), derived from biphenyl, of which 12 are "dioxin-like". Under certain conditions PCBs may form ... Dioxins and dioxin-like compounds (DLCs) are a group of chemical compounds that are persistent organic pollutants (POPs) in the ...
... as well as human-induced cycles for synthetic compounds such as polychlorinated biphenyl (PCB). In some cycles there are ... human-induced cycles for synthetic compounds such as polychlorinated biphenyl (PCB). Biogeochemical Cycles, OpenStax, 9 May ... and phosphorus is returned to the soil where a large part of the phosphorus is transformed into insoluble compounds. Runoff may ... and it is transformed into organic compounds. The plants may then be consumed by herbivores and the phosphorus is either ...
2,2′-Bis(2-indenyl) biphenyl is an organic compound with the formula [C6H4C9H7]2. The compound is the precursor, upon ... Indenyl Compounds for the Polymerization of Olefins US Patent 6,342,622; Jan. 29, 2002. E. G. Ijpeij; F. H. Beijer; H. J. Arts ... Metals studied with 2,2′-bis(2-indenyl) biphenyl include titanium, zirconium, and hafnium.[citation needed] The ligand and its ... compounds with carbon-carbon double bonds-namely, ethylene and propylene.[citation needed] The use of such complexes in the ...
4,4′-Biphenol is an organic compound which is a phenolic derivative of biphenyl. It is a colorless solid. 4,4′-Biphenol is ... "Dimerization of Aromatic Compounds Using Palladium-Carbon-Catalyzed Suzuki-Miyaura Cross-Coupling by One-Pot Synthesis ( ...
Fürst P. Dioxins, polychlorinated biphenyls and other organohalogen compounds in human milk. Levels, correlations, trends and ... Nucleotides Nucleotides are compounds found naturally in human breast milk. They are involved in critical metabolic processes, ... "Bioactive compounds in infant formula and their effects on infant nutrition and health: a systematic literature review." ... Other studies have further found that the levels of most persistent organohalogen compounds in human milk decreased ...
Compounds such as biphenyl and naphthalene are reduced by the powder and form highly coloured radical anions. The powder can ... converts benzyl chloride to bibenzyl in a Wurtz coupling and in a similar fashion dibenzothiophene is reduced to biphenyl. ...
Ingested plastics release toxic compounds, including polychlorinated biphenyls, which may accumulate in internal tissues. Such ... An iron compound, magnetite, in their brains allows the turtles to perceive the Earth's magnetic field, for navigation. Many ... for loggerheads to reach sexual maturity and the high mortality rates of eggs and young turtles from natural phenomena compound ...
This compound and other long-lasting cyano-biphenyls made the twisted nematic display (LCD) popular. Gray wrote the first ...
... with the use of ultrasound the reaction can also be made useful for the production of biphenyl compounds. There are two ... The Direct Preparation of an Organosodium (Potassium) Compound from an RX Compound". Journal of the American Chemical Society. ... The alkyl and aryl radicals then combine to form a substituted aromatic compound. The second approach involves the formation of ... Organosilicon compounds successfully synthesized using the Wurtz-Fittig reaction include silylated calixarenes, t-butylsilicon ...
Its type strain is JCM 7371 (= GIFU 9882). It is notable for degrading a variety of aromatic compounds including biphenyl, ... Not only this, but S. yanoikuyae has also been found in a few locations contaminated by toxic compounds, such as ... More so, the bacteria obtains energy from sources like Dimethyl phthalate (DMP), biphenyl, naphthalene, phenanthrene, toluene, ... the bacteria's ability to grow and survive under low-nutrient conditions as it can utilize a broad range of organic compounds. ...
Computational analysis of this compound suggests valence isomerization to biphenyl is very exothermic but also with a high ... 8]annulyne is known to exist but quickly dimerizes or trimerizes; the compound has been trapped as its radical anion and ... Soc., 1962, 84 (22), pp 4307-4312 doi:10.1021/ja00881a022 Unsaturated Macrocyclic Compounds. XXXVI.1 The Synthesis of Two ... Annulyne and their Reactive Relationships to Heptalene and Biphenyl Brad D. Rose, Richard C. Reiter, and Cheryl D. Stevenson ...
Bay mud Organochlorine compound Polybrominated biphenyl Zodiac, a novel by Neal Stephenson which involves PCBs and their impact ... Polychlorinated biphenyls (PCBs) are highly carcinogenic chemical compounds, formerly used in industrial and consumer products ... Safe S (1984). "Polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs): biochemistry, toxicology, and mechanism ... April 2013). "Carcinogenicity of polychlorinated biphenyls and polybrominated biphenyls" (PDF). The Lancet. Oncology. 14 (4): ...
PCB, or polychlorinated biphenyl, is a chlorine compound that was once widely found in dielectric and coolant fluids used in ... Swackhamer, Deborah L.; Hites, Ronald A. (May 1988). "Occurrence and bioaccumulation of organochlorine compounds in fishes from ... "Learn about Polychlorinated Biphenyls (PCBs) , US EPA". US EPA. Retrieved 2018-10-10.{{cite web}}: CS1 maint: multiple names: ... "persistent organic compounds." Her research more specifically centered on PCBs, dioxins, and pesticides in the Great Lakes ...
Heteroaromatic analogues of the biphenyl compounds also exist, where hindered rotation occurs about a carbon-nitrogen or a ... The use of axially chiral biaryl compounds such as BINAP, QUINAP and BINOL, have been found to be useful in the area of ... Axially chiral biaryl compounds are prepared by coupling reactions, e.g., Ullmann coupling, Suzuki-Miyaura reaction, or ... The atropisomer is an iodoaryl compound synthesised starting from (S)-valine and exists as the (M,S) isomer and the (P,S) ...
Dioxins and dioxin-like compounds Polychlorinated biphenyl "Proceedings of the Subregional Awareness Raising Workshop on ... For general population the most important source is food of animal origin like with other dioxin-like compounds. The most ... doi: 10.1136/oem.59.6.362 Tuomisto J (2019). Dioxins and dioxin-like compounds: toxicity in humans and animals, sources, and ... Polychlorinated dibenzofurans (PCDFs) are a family of organic compounds with one or several of the hydrogens in the ...
EPAL Apparatus for Screening Polychlorinated Biphenyls (PCBs), and Other Chlorinated Compounds," US Patent 5,318,751 (1994). T ... and Other Related Compounds," U.S. Patent 5,272,089 (1993). T. Vo-Dinh, "Raman-Based System for DNA Sequencing, Mapping and ... Chemical Analysis of Polycyclic Aromatic Compounds, Wiley, New York (1989). Vo-Dinh T. and Eastwood D.L., Editors, Laser-Based ... "Dosimeter for Monitoring Vapors and Aerosols of Organic Compounds," U.S. Patent No. 4,680,165 (1987). T. Vo-Dinh, "Practical ...
Synthetic compounds such as polychlorinated biphenyls are found in many pesticides and pollute the green tree frog's aquatic ... Because the frog's skin is thin and permeable, synthetic compounds absorb easily upon contact, making the species a viable ...
... , also known as biphenyl-4-ol and 4-hydroxybiphenyl is an organic compound. It is a phenol analog of biphenyl. 4- ... Biphenyls, All stub articles, Organic compound stubs). ...
In 1991, the Navy discovered nine metals, two semi-volatile organic compounds and a polychlorinated biphenyl in Ford Island's ...
"Aryne coupling" reactions allow for generation of biphenyl compounds which are valuable in pharmaceutical industry, agriculture ... Thus, the process is formally analogous to the E1cb mechanism of aliphatic compounds. Aryl bromides and iodides, on the other ... invoked zwitterionic intermediate in the reaction of fluorobenzene and phenyllithium to give biphenyl. This hypothesis was ...
... is an organic chemical and belongs to a group of compounds called polychlorinated biphenyls. ... 1% of each compound was found in the brain, muscles, and heart while 0.1% was present in the blood. Multiple animal studies, ... All polychlorinated biphenyls are classified as a type B2 carcinogen in the IRIS database after a study found them to be ... "Learn about Polychlorinated Biphenyls (PCBs)". epa.gov. 19 August 2015. Retrieved 2022-02-11. Wahlang B, Song M, Beier J, ...
However, it was later found that the correct structures were of sandwich compound type complexes and based on biphenyl not ... Hein created a mixture of compounds. He was able to produce what he called phenylmagnesium salts. Hein denoted them as: (C6H5) ...
Biphenyl Compounds * Double-Blind Method * Drug Combinations * Enalapril* / administration & dosage * Enalapril* / adverse ...
Gene probes for the selective detection of microorganisms that reductively dechlorinate polychlorinated biphenyl compounds. / ... Gene probes for the selective detection of microorganisms that reductively dechlorinate polychlorinated biphenyl compounds. ... Gene probes for the selective detection of microorganisms that reductively dechlorinate polychlorinated biphenyl compounds. ... Gene probes for the selective detection of microorganisms that reductively dechlorinate polychlorinated biphenyl compounds. ...
HPLC Analysis of Active Cannabinoid Compounds in Gummy Bear Candy on Ascentis® Express Biphenyl with UV Detection after ... HPLC Analysis of Active Cannabinoid Compounds in Gummy Bear Candy on Ascentis® Express Biphenyl ...
Polybrominated biphenyls (PBBs) are chemicals produced by human activity and are found in plastics used in many consumer ... PBBs are mixtures of brominated biphenyl compounds known as congeners.. In the United States, manufacturing of PBBs was stopped ... ToxFAQs™ for Polybrominated Biphenyls (PBBs). Spanish: Bifenilos Polibromados. PDF Versionpdf icon[54.6 KB] This fact sheet ... Polybrominated biphenyls (PBBs) are chemicals produced by human activity and are found in plastics used in many consumer ...
... polychlorinated biphenyl compounds (PCBs), DDT compounds, and TCDD. These toxins can be, and often are, passed on to the ... These issues are compounded by the lack of research on maternal and child health effects caused by the demise of the Aral Sea. ...
LR: 20091119; JID: 101167924; 0 (Antioxidants); 0 (Biphenyl Compounds); 0 (Flavonols); 0 (Formazans); 0 (Glycosides); 0 ( ... No cytotoxic effects were displayed by compounds 1 and 3, but compound 2 was cytotoxic to Vero cells (LC50 = 74.68 microg mL(-1 ... Animals, Antioxidants/chemistry/isolation & purification/pharmacology, Bauhinia/chemistry, Biphenyl Compounds/chemistry, Cattle ... These compounds are reported for the first time from this species. The structures of the compounds were determined on the basis ...
Categories: Biphenyl Compounds Image Types: Photo, Illustrations, Video, Color, Black&White, PublicDomain, CopyrightRestricted ...
Involved in the breakdown of biphenyl-related compounds by Pseudomonas sp.. History. EC 3.7.1.8 created 1989. ... Pathway (7) KEGG PATHWAY (6) KEGG MODULE (1) Chemical substance (6) KEGG COMPOUND (6) Chemical reaction (4) KEGG REACTION (2) ... Cleaves the products from biphenol, 3-isopropylcatechol and 3-methylcatechol produced by EC 1.13.11.39 biphenyl-2,3-diol 1,2- ... 4-dienoic acid hydrolyzing enzyme from Pseudomonas cruciviae S93 B1 involved in the degradation of biphenyl. ...
... and 58 to 92 percent for biphenyl. For nonpolar compounds and for a mixture of a polar and nonpolar compound, no effect was ... a mixture of a polar and nonpolar compound of cellosolve-acetate and biphenyl; and a mixture of two nonpolar compounds ... For polar compounds a dependency was seen on the presence of other compounds. The authors suggest that an adequate explanation ... Loading of the sorbent per 100 milligrams charcoal, volume of the desorbent agent, and the presence or absence of compounds ...
... perfluorinated compounds, phthalates, and bisphenol a in polycystic ovary syndrome: a case-control study. Vagi SJ, Azziz- ... Polychlorinated biphenyl-28. CAS No. 7012-37-5. serum or plasma. Polychlorinated biphenyl-66. CAS No. 33025-41-1. serum or ... Polychlorinated biphenyl-74. CAS No. 32690-93-0. serum or plasma. Polychlorinated biphenyl-99. CAS No. 38380-02-8. serum or ... Polychlorinated biphenyl-105. CAS No. 32598-14-4. serum or plasma. Polychlorinated biphenyl-114. CAS No. 74472-37-0. serum or ...
... known as polychlorinated biphenyls (PCBs), from the country by 2028. ... Polychlorinated biphenyls (PCBs) are organochlorine aromatic compounds classified as persistent organic pollutants that are ... known as polychlorinated biphenyls (PCBs), from the country by 2028. ...
BIPHENYL COMPOUND AS IMMUNOMODULATOR, PREPARATION METHOD THEREFOR AND APPLICATION THEREOF Publication number: 20240109919 ... Abstract: The present invention disclosure also relates to a pharmaceutical composition that ccomprises the compound as an ...
But the soil on the site was contaminated with polychlorinated biphenyls, metals, oil, volatile organic compounds, and ...
Phenyl ring biphenyl Produced by Radiolysis of Fluorinated Hydrocarbons and Related compounds in Solid Media spectra be. ( \ ... For transition metal compounds, large variations can occur due to spin-orbit coupling and zero-field splitting and results in ... Not provide unique identification of compounds determined by the same time the anion. Other component of the odd electron LA ... Nevertheless well-resolved ESR spectra in the radical polymerizations of styrene and its derivatives, diene compounds, ...
are readily degraded, as are such complex compounds as polychlorinated biphenyls (PCBs), dioxins, and chlorofluorocarbons (CFCs ... Even anthropogenic compounds in soil are broken down by many different microorganisms and plants. Chlorinated aliphatics and ... Assume that these microorganisms then produced a polymer or resulted in the precipitation of inorganic compounds that cemented ... Microorganisms can selectively pull or immobilize metals and other inorganic compounds from solution, release enzymes and ...
polychlorinated biphenyl compounds) into a porous lagoon that. overflowed into the stream, and thence into the Mud River. The ...
For the model, they put grains of "naphthalene and biphenyl - two toxic, carbon and hydrogen bearing compounds believed to ...
... are mixtures of up to 209 individual chlorinated compounds (known as congeners). There are no known natural sources of PCBs. ... Polychlorinated biphenyls (PCBs) are mixtures of up to 209 individual chlorinated compounds (known as congeners). There are no ...
Biphenyl Compounds, Cross-Over Studies, Diabetes Mellitus, Type 2, Diabetic Nephropathies, Dose-Response Relationship, Drug, ...
Polychlorinated biphenyls (PCBs) are chlorinated organic compounds widely used in various industrial applications from the… ... Clean Screen® DAU Featured in Method to Analyze Xylazine, p-Fluorofentanyl, Fentanyl, and Fentanyl-Related Compounds in ...
Also, low concentrations of some particularly persistent organic compounds such as polychlorinated biphenyls (PCBs) can be ...
... is the site of a former Monsanto plant where polychlorinated biphenyls (PCBs) were manufactured from 1929 until 1971. Residents ... Matsusue K, Ishii Y, Ariyoshi N, Oguri K: A highly toxic coplanar polychlorinated biphenyl compound suppresses Delta5 and ... polybrominated biphenyls, and polychlorinated biphenyls in human serum. Anal Chem. 2004, 76: 1921-1927. 10.1021/ac030381+. ... Aminov, Z., Haase, R.F., Pavuk, M. et al. Analysis of the effects of exposure to polychlorinated biphenyls and chlorinated ...
Feed and fillets from fish fed the AO diets had lower levels of dioxins and polychlorinated biphenyls (PCBs). Moreover, sensory ... microalgal products reduces contamination of fillets with chemical compounds such as dioxin-like polychlorinated biphenyls ( ... Tacon, A.G.; Metian, M. Global overview on the use of fish meal and fish oil in industrially compounded aquafeeds: Trends and ... Table 4. Amount of heavy metals, dioxins, and dioxin-like polychlorinated biphenyls (DL-PCBs) found in feed and gilthead ...
... and potential pollutants such as organic compounds [adsorbable organic halogens, polychlorinated biphenyls (PCBs), ... Pharmaceutical and other chemical compounds detected in fecal compost, by means of an initial screening of 310 compounds, ... Out of 310 target compounds screened for, 20 substances were detected, with 11 being pharmaceutical compounds. The substances ... Pharmaceutical compound uptake was evaluated as described for yield and N uptake: First, via one-way ANOVA using the mixed ...
N-terminal of Sialoadhesin in complex with Me-a-9-N-(biphenyl-4-carbonyl)-amino-9-deoxy-Neu5Ac (BIP compound). ... N-terminal of Sialoadhesin in complex with Me-a-9-N-(naphthyl-2-carbonyl)-amino-9-deoxy-Neu5Ac (NAP compound). ... N-terminal of Sialoadhesin in complex with Me-a-9-N-benzoyl-amino-9-deoxy-Neu5Ac (BENZ compound). ...
... materials contaminated by toxic compounds called PCBs, or polychlorinated biphenyls. ...
Researchers measured polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs ... perfluorinated compounds (PFCs), mercury and lead, among other chemicals. These industrial pollutants are common in the ... public about the potential health risks of prenatal chemical exposures and reduce the sources of exposure to these compounds," ...
Polychlorinated Biphenyls Medicine & Life Sciences 100% * Polychlorobiphenyl Chemical Compounds 93% * PCB Earth & Environmental ... Spermatogenic capacity in fertile men with elevated exposure to polychlorinated biphenyls. Maria Skaalum Petersen, Jónrit ... Spermatogenic capacity in fertile men with elevated exposure to polychlorinated biphenyls. / Petersen, Maria Skaalum; Hailing, ... Spermatogenic capacity in fertile men with elevated exposure to polychlorinated biphenyls. In: Environmental Research. 2015 ; ...
  • 1995. Organochlorine compounds and estrogen-related cancers in women. (cdc.gov)
  • Polychlorinated biphenyls (PCBs) are organochlorine aromatic compounds classified as persistent organic pollutants that are subject to the restrictions imposed by the Stockholm Convention. (undp.org)
  • Polychlorinated biphenyls (PCBs) are synthetic, organochlorine compounds previously used in industrial processes. (cdc.gov)
  • Some adverse effects of hydroxylated polychlorinated biphenyls (OH-PCBs) in humans are presumed to be initiated via thyroid hormone receptor (TR) binding. (bvsalud.org)
  • His scientific research work concerns mainly persistent organic pollutants and other highly toxic compounds, including dioxins, furans, polychlorinated biphenyls, volatile organic compounds and pesticides. (who.int)
  • Marine turtles of all species, particularly hawksbill turtles ( Figure 1 ), can contain a variety of toxins including heavy metals (e.g. cadmium and mercury), organic compounds (e.g. pesticides such as chlordane and polychlorinated biphenyls) and biotoxins such as those produced by various blue-green algae on which turtles feed (e.g. lyngbyatoxin A from Lyngbya majuscula ). (who.int)
  • With financial support from the Global Environment Facility (the GEF) the United Nations Development Programme (UNDP) continues to work with the Ministry of Natural Resources and Environmental Protection to keep Belarus on track to remove hazardous chemical pollutants, known as polychlorinated biphenyls (PCBs), from the country by 2028. (undp.org)
  • Polychlorinated biphenyls (PCBs) are mixtures of up to 209 individual chlorinated compounds (known as congeners). (wa.gov)
  • Also, low concentrations of some particularly persistent organic compounds such as polychlorinated biphenyls (PCBs) can be found in surficial soils and sediment throughout much of the state due to global distribution of these hazardous substances. (wa.gov)
  • Anniston, Alabama, is the site of a former Monsanto plant where polychlorinated biphenyls (PCBs) were manufactured from 1929 until 1971. (biomedcentral.com)
  • Such microalgae oils are sustainable alternatives, rich in essential fatty acids and free of dioxins and polychlorinated biphenyls (PCBs). (mdpi.com)
  • Background: Endocrine disrupting industrial chemicals, such as polychlorinated biphenyls (PCBs), are suspected to adversely affect male reproductive functions. (pure.fo)
  • Growth of organohalide-respiring bacteria such as Dehalococcoides mccartyi on halogenated organics (e.g., polychlorinated biphenyls (PCBs)) at contaminated sites or in enrichment culture requires interaction and support from other microbial community members. (bvsalud.org)
  • In some sediment environments, the sorption kinetics onto AC may significantly impact remedial performance, particularly for large, highly hydrophobic contaminants such as PCBs, but there is limited kinetic data on such compounds. (bvsalud.org)
  • Since, however, the numbers were small, dose-response relationships could not be evaluated, and the role of compounds other than PCBs could not be excluded, the evidence was considered to be limited. (who.int)
  • Polychlorinated biphenyls,polychlorinated terphenyls (PCBs and PCTs : health and safety guide. (who.int)
  • But the soil on the site was contaminated with polychlorinated biphenyls, metals, oil, volatile organic compounds, and polycyclic aromatic hydrocarbons. (cdc.gov)
  • PBBs are mixtures of brominated biphenyl compounds known as congeners. (cdc.gov)
  • An article "Use of mechanistic data in the IARC evaluations of the carcinogenicity of polychlorinated biphenyls and related compounds" has also been published in Environmental Science and Pollution Research International . (who.int)
  • Since PBBs are no longer produced or used, the risk of Studies in animals exposed to large amounts of PBBs for a exposure to these compounds is low. (cdc.gov)
  • Our findings highlight the need to inform policymakers and the public about the potential health risks of prenatal chemical exposures and reduce the sources of exposure to these compounds," Woodruff said. (scienceblog.com)
  • 1997. Inhibition of L-aromatic amino acid decarboxylase by polychlorinated biphenyls. (cdc.gov)
  • Polychlorinated biphenyls and polybrominated biphenyls / this publication represents the views and expert opinions of two IARC Working Groups on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, which met in Lyon, 10-15 October 1977 and 6-13 June 1978. (who.int)
  • For the model, they put grains of "naphthalene and biphenyl - two toxic, carbon and hydrogen bearing compounds believed to exist on Titan's surface - into a small cylinder. (voanews.com)
  • and the inset map of the Federated States of Micronesia was reproduced from WHO Division of Pacific Technical Support ( http://www.wpro.who.int/southpacific/pacelf/ countries/fsm/en/ ). (who.int)
  • Loading of the sorbent per 100 milligrams charcoal, volume of the desorbent agent, and the presence or absence of compounds other than the analyte were examined. (cdc.gov)
  • For nonpolar compounds and for a mixture of a polar and nonpolar compound, no effect was observed for the presence of any one compound in the mixture on the desorption efficiency of the others. (cdc.gov)
  • For polar compounds a dependency was seen on the presence of other compounds. (cdc.gov)
  • HIGHLIGHTS: Polybrominated biphenyls (PBBs) are chemicals produced by human activity and are found in plastics used in many consumer products to make them difficult to burn. (cdc.gov)
  • Cleaves the products from biphenol, 3-isopropylcatechol and 3-methylcatechol produced by EC 1.13.11.39 biphenyl-2,3-diol 1,2-dioxygenase, by ring-fission at a -CO-C bond. (genome.jp)
  • WHO Task Group on Environmental Health Criteria for Polychlorinated Biphenyls and Terphenyls. (who.int)
  • Polybrominated biphenyls (PBBs : health and safety guide. (who.int)
  • Polychlorinated biphenyls and polybrominated biphenyls / this publication represents the views and expert opinions of two IARC Working Groups on the Evaluation of the Carcinogenic Risk of Chemicals to Humans, which met in Lyon, 10-15 October 1977 and 6-13 June 1978. (who.int)
  • HIGHLIGHTS: Polybrominated biphenyls (PBBs) are chemicals produced by human activity and are found in plastics used in many consumer products to make them difficult to burn. (cdc.gov)
  • Marine bacterial strains (BP-PH, CAR-SF, and DBF-MAK) were isolated using biphenyl, carbazole (CAR), or dibenzofuran (DF) respectively as substrates for growth. (elsevierpure.com)
  • PBBs are mixtures of brominated biphenyl compounds known as congeners. (cdc.gov)
  • But the soil on the site was contaminated with polychlorinated biphenyls, metals, oil, volatile organic compounds, and polycyclic aromatic hydrocarbons. (cdc.gov)
  • Whitish aromatic crystalline organic compounds made up of two conjoined BENZENE rings. (nih.gov)
  • Organic Chemistry is a sub-discipline of chemistry that deals with carbon compounds. (highermpact.org)
  • Microorganisms are known to be capable of degrading diverse chemical substances including man-made chemicals in the environment that are mostly aromatic compounds. (kegg.jp)
  • 1997. Inhibition of L-aromatic amino acid decarboxylase by polychlorinated biphenyls. (cdc.gov)
  • This diagram illustrates combination patterns of reaction modules for biodegradation of aromatic compounds, consisting of three main types of ring dihydroxylation modules, followed by meta- or ortho-cleavage modules, together with an optional preprocessing module for converting methyl group to carboxyl group on the aromatic ring. (kegg.jp)
  • In this contribution we report the synthesis and evaluation of three fragments of the dimeric lead compound by structural simplifications. (rsc.org)
  • Weak molecular forces, such as Van der Waal forces, provide the driving force for physical adsorption, while a chemical reaction forms a much stronger chemical bond between the compound and the surface of the solid in chemisorption. (frtr.gov)
  • Summary: Our structure-based virtual screening model selected hamamelitannin, glucocheirolin, aminopterin, and pemetrexed as compounds that may act as potential inhibitors for improving endocrine therapies for breast cancer. (edrc2013.org)
  • [ 120 ] and schinol and a new biphenyl compound were active on Paracoccidioides brasiliensis . (medscape.com)
  • 11. Biomagnification of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls in a highly contaminated freshwater food web from South China. (nih.gov)
  • 2234-13-1 with some of these highly lipophilic, bioaccumulating compounds. (nih.gov)
  • Data concerning a total of 49,752 compounds were downloaded from your natural product databases of the Ambinter (n=41,588), Selleck (n=146), Natural products database of Universidad Estadual de Feria de Santana (UEFS) (n=499), SPECS (n=701), and Traditional Chinese Medicine database Taiwan (n=6,818) and retrieved from your ZINC database (https://zinc.docking.org/, accessed on: 19 Jan 2012) (33) for virtual testing. (edrc2013.org)
  • 9. Polybrominated diphenyl ethers and polychlorinated biphenyls in freshwater fish from Taihu Lake, China: their levels and the factors that influence biomagnification. (nih.gov)
  • Computational studies suggest a common pharmacophore of the distinctive biphenyl motifs. (rsc.org)
  • [ 107 ] From several parts (flower, leaf and stem containing different compounds) of Aloysia triphylla , Gypsophila bicolor , Lavandula viridis , Erigeron acris and annuus , and also from star anise ( Illicium verum ) an activity, linked to trans-anethole, was observed. (medscape.com)
  • Promising activity against C. albicans biofilm formation was displayed by eugenol and cinnamaldehyde, molecules belonging to the phenolic group of essential oil compounds, [ 114 ] which also showed synergy with fluconazole in vitro . (medscape.com)
  • containing caryophyllene as major compound, displayed varying degrees of antimicrobial activity, in particular against Cryptococcus neoformans . (medscape.com)