Rhodococcus: A bacterial genus of the order ACTINOMYCETALES.Acrylonitrile: A highly poisonous compound used widely in the manufacture of plastics, adhesives and synthetic rubber.Gloves, Protective: Coverings for the hands, usually with separations for the fingers, made of various materials, for protection against infections, toxic substances, extremes of hot and cold, radiations, water immersion, etc. The gloves may be worn by patients, care givers, housewives, laboratory and industrial workers, police, etc.Cyclization: Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)AminohydrolasesGlucosinolates: Substituted thioglucosides. They are found in rapeseed (Brassica campestris) products and related cruciferae. They are metabolized to a variety of toxic products which are most likely the cause of hepatocytic necrosis in animals and humans.Alkenes: Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)Nucleoside Q: A modified nucleoside which is present in the first position of the anticodon of tRNA-tyrosine, tRNA-histidine, tRNA-asparagine and tRNA-aspartic acid of many organisms. It is believed to play a role in the regulatory function of tRNA. Nucleoside Q can be further modified to nucleoside Q*, which has a mannose or galactose moiety linked to position 4 of its cyclopentenediol moiety.Cobalt: A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.IminesAcetonitriles: Compounds in which a methyl group is attached to the cyano moiety.Stereoisomerism: 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)Gloves, Surgical: Gloves, usually rubber, worn by surgeons, examining physicians, dentists, and other health personnel for the mutual protection of personnel and patient.Molecular Structure: 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.Latex: A milky, product excreted from the latex canals of a variety of plant species that contain cauotchouc. Latex is composed of 25-35% caoutchouc, 60-75% water, 2% protein, 2% resin, 1.5% sugar & 1% ash. RUBBER is made by the removal of water from latex.(From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed). Hevein proteins are responsible for LATEX HYPERSENSITIVITY. Latexes are used as inert vehicles to carry antibodies or antigens in LATEX FIXATION TESTS.Perfume: A substance, extract, or preparation for diffusing or imparting an agreeable or attractive smell, especially a fluid containing fragrant natural oils extracted from flowers, woods, etc., or similar synthetic oils. (Random House Unabridged Dictionary, 2d ed)AcetalsBrevibacterium: A gram-positive organism found in dairy products, fresh and salt water, marine organisms, insects, and decaying organic matter.Alkynes: Hydrocarbons with at least one triple bond in the linear portion, of the general formula Cn-H2n-2.Oximes: Compounds that contain the radical R2C=N.OH derived from condensation of ALDEHYDES or KETONES with HYDROXYLAMINE. Members of this group are CHOLINESTERASE REACTIVATORS.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.AmidohydrolasesPalladium: A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.Cycloaddition Reaction: Synthetic organic reactions that use reactions between unsaturated molecules to form cyclical products.Amides: Organic compounds containing the -CO-NH2 radical. Amides are derived from acids by replacement of -OH by -NH2 or from ammonia by the replacement of H by an acyl group. (From Grant & Hackh's Chemical Dictionary, 5th ed)Organic Chemistry Phenomena: The conformation, properties, reaction processes, and the properties of the reactions of carbon compounds.Ammonium Hydroxide: The hydroxy salt of ammonium ion. It is formed when AMMONIA reacts with water molecules in solution.Oxides: Binary compounds of oxygen containing the anion O(2-). The anion combines with metals to form alkaline oxides and non-metals to form acidic oxides.Cysteine Proteases: A subclass of peptide hydrolases that depend on a CYSTEINE residue for their activity.Latex Hypersensitivity: Allergic reaction to products containing processed natural rubber latex such as rubber gloves, condoms, catheters, dental dams, balloons, and sporting equipment. Both T-cell mediated (HYPERSENSITIVITY, DELAYED) and IgE antibody-mediated (HYPERSENSITIVITY, IMMEDIATE) allergic responses are possible. Delayed hypersensitivity results from exposure to antioxidants present in the rubber; immediate hypersensitivity results from exposure to a latex protein.Acrylamides: Colorless, odorless crystals that are used extensively in research laboratories for the preparation of polyacrylamide gels for electrophoresis and in organic synthesis, and polymerization. Some of its polymers are used in sewage and wastewater treatment, permanent press fabrics, and as soil conditioning agents.Hydrazones: Compounds of the general formula R:N.NR2, as resulting from the action of hydrazines with aldehydes or ketones. (Grant & Hackh's Chemical Dictionary, 5th ed)TextilesSpectrophotometry, Infrared: Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Hydrogenation: Addition of hydrogen to a compound, especially to an unsaturated fat or fatty acid. (From Stedman, 26th ed)Alkylation: The covalent bonding of an alkyl group to an organic compound. It can occur by a simple addition reaction or by substitution of another functional group.Enzyme Stability: The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.Isothiocyanates: Organic compounds with the general formula R-NCS.Chemistry Techniques, Synthetic: Methods used for the chemical synthesis of compounds. Included under this heading are laboratory methods used to synthesize a variety of chemicals and drugs.Isoxazoles: Azoles with an OXYGEN and a NITROGEN next to each other at the 1,2 positions, in contrast to OXAZOLES that have nitrogens at the 1,3 positions.Steroid Isomerases: Enzymes that catalyze the transposition of double bond(s) in a steroid molecule. EC 5.3.3.SemicarbazonesSolvents: Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)Combinatorial Chemistry Techniques: A technology, in which sets of reactions for solution or solid-phase synthesis, is used to create molecular libraries for analysis of compounds on a large scale.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Benzyl CompoundsModels, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.DNA Barcoding, Taxonomic: Techniques for standardizing and expediting taxonomic identification or classification of organisms that are based on deciphering the sequence of one or a few regions of DNA known as the "DNA barcode".Rhodium: Rhodium. A hard and rare metal of the platinum group, atomic number 45, atomic weight 102.905, symbol Rh. (Dorland, 28th ed)Vibration: A continuing periodic change in displacement with respect to a fixed reference. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Spectrum Analysis: The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Cosmetics: Substances intended to be applied to the human body for cleansing, beautifying, promoting attractiveness, or altering the appearance without affecting the body's structure or functions. Included in this definition are skin creams, lotions, perfumes, lipsticks, fingernail polishes, eye and facial makeup preparations, permanent waves, hair colors, toothpastes, and deodorants, as well as any material intended for use as a component of a cosmetic product. (U.S. Food & Drug Administration Center for Food Safety & Applied Nutrition Office of Cosmetics Fact Sheet (web page) Feb 1995)KetonesThiocyanates: Organic derivatives of thiocyanic acid which contain the general formula R-SCN.Infrared Rays: That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.Molecular Sequence Data: 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.Amines: A group of compounds derived from ammonia by substituting organic radicals for the hydrogens. (From Grant & Hackh's Chemical Dictionary, 5th ed)Spectroscopy, Fourier Transform Infrared: A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.Actinobacteria: Class of BACTERIA with diverse morphological properties. Strains of Actinobacteria show greater than 80% 16S rDNA/rRNA sequence similarity among each other and also the presence of certain signature nucleotides. (Stackebrandt E. et al, Int. J. Syst. Bacteriol. (1997) 47:479-491)Biocatalysis: The facilitation of biochemical reactions with the aid of naturally occurring catalysts such as ENZYMES.Furans: Compounds with a 5-membered ring of four carbons and an oxygen. They are aromatic heterocycles. The reduced form is tetrahydrofuran.Iodine: A nonmetallic element of the halogen group that is represented by the atomic symbol I, atomic number 53, and atomic weight of 126.90. It is a nutritionally essential element, especially important in thyroid hormone synthesis. In solution, it has anti-infective properties and is used topically.Spiro Compounds: A group of compounds consisting in part of two rings sharing one atom (usually a carbon) in common.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Catalytic Domain: The region of an enzyme that interacts with its substrate to cause the enzymatic reaction.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Hydrolysis: The process of cleaving a chemical compound by the addition of a molecule of water.Aldehydes: Organic compounds containing a carbonyl group in the form -CHO.Needlestick Injuries: Penetrating stab wounds caused by needles. They are of special concern to health care workers since such injuries put them at risk for developing infectious disease.Materials Testing: The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.Metals: Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)Cyanides: Inorganic salts of HYDROGEN CYANIDE containing the -CN radical. The concept also includes isocyanides. It is distinguished from NITRILES, which denotes organic compounds containing the -CN radical.Glycosides: Any compound that contains a constituent sugar, in which the hydroxyl group attached to the first carbon is substituted by an alcoholic, phenolic, or other group. They are named specifically for the sugar contained, such as glucoside (glucose), pentoside (pentose), fructoside (fructose), etc. Upon hydrolysis, a sugar and nonsugar component (aglycone) are formed. (From Dorland, 28th ed; From Miall's Dictionary of Chemistry, 5th ed)Organometallic Compounds: 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)Crystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Molecular Conformation: The characteristic three-dimensional shape of a molecule.Molecular Dynamics Simulation: A computer simulation developed to study the motion of molecules over a period of time.Magnetic Resonance Spectroscopy: 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).Pseudomonas putida: A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.Iron: A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Equipment Failure: Failure of equipment to perform to standard. The failure may be due to defects or improper use.Cysteine: A thiol-containing non-essential amino acid that is oxidized to form CYSTINE.Enzymes: Biological molecules that possess catalytic activity. They may occur naturally or be synthetically created. Enzymes are usually proteins, however CATALYTIC RNA and CATALYTIC DNA molecules have also been identified.Spectrophotometry, Ultraviolet: Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Eukaryota: One of the three domains of life (the others being BACTERIA and ARCHAEA), also called Eukarya. These are organisms whose cells are enclosed in membranes and possess a nucleus. They comprise almost all multicellular and many unicellular organisms, and are traditionally divided into groups (sometimes called kingdoms) including ANIMALS; PLANTS; FUNGI; and various algae and other taxa that were previously part of the old kingdom Protista.PhotochemistryNickel: A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.Kinetics: The rate dynamics in chemical or physical systems.Butyric Acid: A four carbon acid, CH3CH2CH2COOH, with an unpleasant odor that occurs in butter and animal fat as the glycerol ester.Sulfhydryl Compounds: Compounds containing the -SH radical.Chromatography, Ion Exchange: Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Hydrogen Bonding: A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Pseudomonas: A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.Static Electricity: The accumulation of an electric charge on a objectOxidation-Reduction: 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).Carbon: A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.Occupational Exposure: The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.Molecular Weight: The sum of the weight of all the atoms in a molecule.Glucuronides: Glycosides of GLUCURONIC ACID formed by the reaction of URIDINE DIPHOSPHATE GLUCURONIC ACID with certain endogenous and exogenous substances. Their formation is important for the detoxification of drugs, steroid excretion and BILIRUBIN metabolism to a more water-soluble compound that can be eliminated in the URINE and BILE.Genes, Bacterial: The functional hereditary units of BACTERIA.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.Multigene Family: A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Ligands: A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Indicators and Reagents: Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Arabidopsis: A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.Spectrophotometry: The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.Ribonucleases: Enzymes that catalyze the hydrolysis of ester bonds within RNA. EC 3.1.-.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Structure-Activity Relationship: 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.Gene Transfer, Horizontal: The naturally occurring transmission of genetic information between organisms, related or unrelated, circumventing parent-to-offspring transmission. Horizontal gene transfer may occur via a variety of naturally occurring processes such as GENETIC CONJUGATION; GENETIC TRANSDUCTION; and TRANSFECTION. It may result in a change of the recipient organism's genetic composition (TRANSFORMATION, GENETIC).Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Arabidopsis Proteins: Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.Bacterial Proteins: Proteins found in any species of bacterium.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Enzyme Activation: Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Nitriles: Organic compounds containing the -CN radical. The concept is distinguished from CYANIDES, which denotes inorganic salts of HYDROGEN CYANIDE.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.

Estrogenic potential of certain pyrethroid compounds in the MCF-7 human breast carcinoma cell line. (1/3723)

Estrogens, whether natural or synthetic, clearly influence reproductive development, senescence, and carcinogenesis. Pyrethroid insecticides are now the most widely used agents for indoor pest control, providing potential for human exposure. Using the MCF-7 human breast carcinoma cell line, we studied the estrogenic potential of several synthetic pyrethroid compounds in vitro using pS2 mRNA levels as the end point. We tested sumithrin, fenvalerate, d-trans allethrin, and permethrin. Nanomolar concentrations of either sumithrin or fenvalerate were sufficient to increase pS2 expression slightly above basal levels. At micromolar concentrations, these two pyrethroid compounds induced pS2 expression to levels comparable to those elicited by 10 nM 17ss-estradiol (fivefold). The estrogenic activity of sumithrin was abolished with co-treatment with an antiestrogen (ICI 164,384), whereas estrogenic activity of fenvalerate was not significantly diminished with antiestrogen co-treatment. In addition, both sumithrin and fenvalerate were able to induce cell proliferation of MCF-7 cells in a dose-response fashion. Neither permethrin nor d-trans allethrin affected pS2 expression. Permethrin had a noticeable effect on cell proliferation at 100 microM, whereas d-trans allethrin slightly induced MCF-7 cell proliferation at 10 microM, but was toxic at higher concentrations. Overall, our studies imply that each pyrethroid compound is unique in its ability to influence several cellular pathways. These findings suggest that pyrethroids should be considered to be hormone disruptors, and their potential to affect endocrine function in humans and wildlife should be investigated.  (+info)

Androgen-independent induction of prostate-specific antigen gene expression via cross-talk between the androgen receptor and protein kinase A signal transduction pathways. (2/3723)

Transcription of the prostate-specific antigen (PSA) gene escapes regulation by androgens in advanced prostate cancer. To determine the molecular mechanism(s) of androgen-independent regulation of the PSA gene, the possibility that the androgen receptor (AR) is activated in the absence of androgen by stimulation of protein kinase A (PKA) was investigated. Activation of PKA by forskolin resulted in elevated expression of the PSA gene in androgen-depleted LNCaP cells, an effect that was blocked by the antiandrogen, bicalutamide. Further evidence that induction of PSA gene expression was dependent on AR was obtained from experiments using PC3 cells devoid of AR. Neither PSA, PB, nor ARR3 androgen-responsive reporters could be induced by activation of PKA in the absence of transfected AR. In addition, when nuclear AR from forskolin-treated LNCaP cells was incubated with oligonucleotides encoding an androgen response element of the PSA promoter and examined by electromobility shift assay, an increase in AR-androgen response element complex formation was observed. Lastly, cotransfection of an expression vector for a chimeric protein encoding the amino-terminal domain of the human AR linked to Gal4 and a 5xGal4UAS reporter gene construct resulted in activation of the amino-terminal domain of the AR by stimulation of PKA activity. These results demonstrate androgen-independent induction of PSA gene expression in prostate cancer cells by an AR-dependent pathway.  (+info)

Rational design and synthesis of a novel anti-leukemic agent targeting Bruton's tyrosine kinase (BTK), LFM-A13 [alpha-cyano-beta-hydroxy-beta-methyl-N-(2, 5-dibromophenyl)propenamide]. (3/3723)

In a systematic effort to design potent inhibitors of the anti-apoptotic tyrosine kinase BTK (Bruton's tyrosine kinase) as anti-leukemic agents with apoptosis-promoting and chemosensitizing properties, we have constructed a three-dimensional homology model of the BTK kinase domain. Our modeling studies revealed a distinct rectangular binding pocket near the hinge region of the BTK kinase domain with Leu460, Tyr476, Arg525, and Asp539 residues occupying the corners of the rectangle. The dimensions of this rectangle are approximately 18 x 8 x 9 x 17 A, and the thickness of the pocket is approximately 7 A. Advanced docking procedures were employed for the rational design of leflunomide metabolite (LFM) analogs with a high likelihood to bind favorably to the catalytic site within the kinase domain of BTK. The lead compound LFM-A13, for which we calculated a Ki value of 1.4 microM, inhibited human BTK in vitro with an IC50 value of 17.2 +/- 0.8 microM. Similarly, LFM-A13 inhibited recombinant BTK expressed in a baculovirus expression vector system with an IC50 value of 2.5 microM. The energetically favorable position of LFM-A13 in the binding pocket is such that its aromatic ring is close to Tyr476, and its substituent group is sandwiched between residues Arg525 and Asp539. In addition, LFM-A13 is capable of favorable hydrogen bonding interactions with BTK via Asp539 and Arg525 residues. Besides its remarkable potency in BTK kinase assays, LFM-A13 was also discovered to be a highly specific inhibitor of BTK. Even at concentrations as high as 100 micrograms/ml (approximately 278 microM), this novel inhibitor did not affect the enzymatic activity of other protein tyrosine kinases, including JAK1, JAK3, HCK, epidermal growth factor receptor kinase, and insulin receptor kinase. In accordance with the anti-apoptotic function of BTK, treatment of BTK+ B-lineage leukemic cells with LFM-A13 enhanced their sensitivity to ceramide- or vincristine-induced apoptosis. To our knowledge, LFM-A13 is the first BTK-specific tyrosine kinase inhibitor and the first anti-leukemic agent targeting BTK.  (+info)

Oxidation of low density lipoprotein and plasma by 15-lipoxygenase and free radicals. (4/3723)

It is generally accepted that the oxidation of pentadiene structures of polyunsaturated lipids by lipoxygenase (LOX) is regio- and enantio-specific, while the free radical-mediated lipid peroxidation gives stereo-random racemic products. It was confirmed that the oxidation of human low density lipoprotein (LDL) by 15-LOX from rabbit reticulocytes gave phosphatidylcholine (PC) and cholesteryl ester (CE) hydroperoxides regio-, stereo- and enantio-specifically. 15-LOX also oxidized human plasma to give specific PC and CE hydroperoxides in spite of the presence of high concentrations of antioxidants. More CE hydroperoxides were formed than PC hydroperoxides from LDL, but the reverse order was observed for plasma oxidation. The S/R ratio of the hydroperoxides decreased during long time incubation but remained significantly larger than one, while free radical-mediated oxidation of LDL and plasma gave racemic products.  (+info)

Control of malaria vectors: cost analysis in a province of northern Vietnam. (5/3723)

The cost of permethrin-treated bednets (50% EC; 0.2 g/m2, 2 rounds per year) was compared to the cost of residual spraying with lambdacyhalothrin 10% WP (0.03 g/m2, once yearly) in Hoa Binh, a mountainous province in northern Vietnam. Calculations of the amounts of insecticides needed were based on national guidelines, on data from a cross-sectional survey and on district activity reports. The actual cost of insecticide required per person per year was lower for impregnation (US$ 0.26) than for spraying (US$ 0.36), but the difference was smaller than expected. The total cost for impregnated bednets per person per year amounted to US$ 0.90 compared to USS 0.47 for spraying. The determining factor was the cost of the net, amounting to US$ 0.58 per person per year, assuming a 5-year life of the net. Other material (excluding nets), labour and transport combined, accounted for only 17% of the impregnation cost and 23% of spraying expenses. However, for the National Malaria Control Programme of Vietnam, the cost per person per year for impregnated bednets amounted to US$ 0.32 only, because the vast majority of nets are bought by the population. For spraying, the programme had to bear the entire cost.  (+info)

Molecular characterisation of a novel thermophilic nitrile hydratase. (6/3723)

The thermophilic soil isolate, Bacillus pallidus Dac521, expresses a constitutive nitrile hydratase. The purified enzyme was found to be a 110 kDa tetramer composed of two alpha and two beta subunits with molecular masses of 27 kDa and 29 kDa, respectively. The enzyme electrophoresed as a single protein band on native PAGE but two protein bands with isoelectric points of 4.7 and 5.5 on isoelectric focusing suggested the presence of isozymes. The purified enzyme was moderately thermostable up to 55 degrees C and the enzyme activity was stable over a broad pH range. Comparisons of the N-terminal amino acid sequences of the nitrile hydratase subunits with those of other nitrile hydratases showed up to 90% identity for the beta subunit sequence but no significant identity for the alpha subunit. The enzyme hydrolysed a narrow range of aliphatic substrates and did not hydrolyse any of the cyclic, hydroxy-, di- or aromatic nitriles tested. The activity was irreversibly inhibited by the aromatic nitrile, benzonitrile. The kinetic constants for acetonitrile, acrylonitrile and propionitrile compared favourably with those of mesophilic nitrile hydratases.  (+info)

Role of cytochrome P-450 2E1 in methacrylonitrile metabolism and disposition. (7/3723)

Methacrylonitrile (MAN) is a widely used aliphatic nitrile and is structurally similar to the known rat carcinogen and suspected human carcinogen acrylonitrile (AN). There is evidence that AN is metabolized via the cytochrome P-450 (CYP) 2E1. Recently, we identified two biliary conjugates originating from the interaction of MAN and its epoxide with glutathione. Mercapturic acids formed via the degradation of the two conjugates were also identified in rat and mouse urine. Additionally, a significant portion of MAN was eliminated in the expired air as CO2 (formed via the epoxide pathway) and unchanged MAN. The objective of the present work was to determine whether CYP2E1 is involved in the oxidative metabolism of MAN as was suggested for AN. 2-14C-MAN was administered to CYP2E1-null or wild-type mice by gavage at 12 mg/kg. Although total urinary and fecal excretion of MAN-derived radioactivity was slightly different in CYP2E1-null versus wild-type mice, the ratio of mercapturic acids originating from the epoxide-glutathione versus MAN-glutathione conjugates were lower in urine of CYP2E1-null mice than in that of wild-type animals. Exhalation of MAN-derived organic volatiles (primarily parent MAN) was 12- and 42-fold greater in female and male CYP2E1-null mice than in wild-type mice, respectively. Additionally, exhalation of CO2 derived from metabolism of MAN via the CYP2E1 pathway was 3- to 5-fold greater in wild-type than in CYP2E1-null animals. Although these data indicate that CYP2E1 is the principal enzyme responsible for the oxidative metabolism of MAN, other cytochrome P-450 enzymes may be involved. Assessment of MAN metabolism in CYP2E1-null mice pretreated with 1-aminobenzotriazole (CYP inhibitor) resulted in a further decrease in oxidative metabolites of MAN. Comparison of the tissue concentrations of MAN-derived radioactivity in mouse tissues revealed that MAN-derived radioactivity is generally higher in wild-type > CYP2E1-null mice > CYP2E1-null mice pretreated with 1-aminobenzotriazole, suggesting a direct relationship between MAN oxidative metabolism and the half-life of MAN and/or its metabolites in various tissues. It is therefore concluded that MAN oxidative metabolites such as the epoxide intermediate have greater reactivity than parent MAN.  (+info)

A new strategy for treating nets. Part 1: formulation and dosage. (8/3723)

The conventional dosages of pyrethroid insecticides on mosquito nets assume that nets will be retreated at 6-12 month intervals. However, dosage should be related to washing of nets; if nets are only washed once or twice a year, their dosage requirements will be different to those which are washed fortnightly. A 'low-dose, frequent-wash' retreatment system might be technically more appropriate and more affordable where nets are washed frequently, as they are in Dar es Salaam. Moreover, for use as a domestic insecticide, water-based formulations of pyrethroid are preferable to the more commonly used emulsifiable concentrates (ECs). This paper reports laboratory evaluations of three formulations (ECs, Flowable, CS) of three pyrethroids (deltamethrin, lambdacyhalothrin, permethrin). Insecticidal activity was tested using serial bioassays at a range of dosages using Anopheles gambiae. The water-based formulations were no less effective than the ECs, even at the lowest dosages. Nets treated with 3 mg/m2 and then repeatedly washed and retreated after each wash with either 3 mg/m2 or 1 mg/m2 were subjected to gas chromatography analysis. This showed that the amounts of pyrethroid in the nets accumulated rapidly over the first few wash-retreatment cycles and then remained fairly stable over subsequent cycles. These nets gave consistently high bioassay mortalities throughout the experiment, while the mortality declined rapidly after several washes with the nets that were treated at 3 mg/m2 but not retreated. Experimental huts were used to compare the effectiveness of these 2 net retreatment regimes and nets which were not retreated. All nets caused high mortality rates amongst Anopheles females, but had negligible effects on culicines; either in killing them or in preventing feeding. Therefore use of a high 'loading' dose for initial treatment with lower 'maintenance' doses for retreatment may be preferable to ensure that net users promptly perceive the benefits of the insecticide against culicines.  (+info)

  • Nitriles can be prepared by the dehydration of primary amides. (wikipedia.org)
  • In the presence of ethyl dichlorophosphate and DBU benzamide converts to benzonitrile: Two intermediates in this reaction are amide tautomer A and its phosphate adduct B. In a related dehydration, secondary amides give nitriles by the von Braun amide degradation. (wikipedia.org)
  • In a related dehydration , secondary amides give nitriles by the von Braun amide degradation . (wikipedia.org)
  • The reduction of nitriles and amides to the corresponding amines with tetra- n -butylammonium borohydride in dichloromethane has been reported, in which the other functional groups such as ester, nitro, and halogen attached to the aromatic ring are not affected. (erowid.org)
  • The reduction of nitriles and amides to the amines is a very important, but not so easy organic transformation. (erowid.org)
  • The improved methods for the reduction of nitriles 1 and amides 2 with complex metal hydrides have been so far reported. (erowid.org)
  • We wish herein to describe another convenient and efficient method for the reduction of nitriles and amides to the amines with tetra- n -butylammonium borohydride 3-6 in refluxing dichloromethane, in which the chemospecificity of tetra- n -butylammonium borohydride toward organic cyano and amide compounds was observed. (erowid.org)
  • Esters, amides, and nitriles are carboxylic acid derivatives that can be prepared starting from either carboxylic acids or other carboxylic acid derivatives. (coursehero.com)
  • For instance, nitriles can be obtained by a direct dehydration of primary amides RCONH2, and vice versa, primary amides - by an addition of water to nitriles. (perfumerflavorist.com)
  • Conversions of nitriles to N-substituted secondary or tertiary amides are also quite practical, although they often require more than one chemical step. (perfumerflavorist.com)
  • As they are more puncture resistant than natural material gloves, dispensable varieties of nitrile work gloves are often the preferred choice for use in medical or food preparation environments due to their suitability to higher risk situations. (screwfix.com)
  • One reason behind this is that the best nitrile work gloves are perfect for tough jobs. (edcmag.com)
  • To gather more information about the best nitrile work gloves, we have compiled ten of the most popular and satisfying products in this industry. (edcmag.com)
  • Whether you're a professional tradesman, a serious hobbyist, or anything in between, these Wells Lamont nitrile-dipped work gloves are the ideal way to keep your hands safe. (bunnings.com.au)
  • A.M. Leonard carries a wide assortment of nitrile work gloves, gloves and other work wear . (amleo.com)
  • Our nitrile work gloves are tough with a formidable grip, but also flexible, allowing great dexterity. (amleo.com)
  • We offer a variety of nitrile work gloves, including the popular dipped design with coating over only the palm & fingers, increasing breathability and comfort. (amleo.com)
  • As an added bonus, these items are made of nitrile, which means workers and patients with a latex allergy don't need to worry about flare-ups. (webstaurantstore.com)
  • Several professionals even depend on the sturdiness on gloves made of nitrile material, especially if they are exposed to blood-borne pathogens as well as other contaminants in the environment. (edcmag.com)
  • In the latter case, competitive addition of the alkyl group to the nitrile takes place. (wikipedia.org)
  • Polyanions of nitriles can also be generated by multiple deprotonations, and these species produce polyalkylated products in the presence of alkyl electrophiles. (wikipedia.org)
  • First up: a category of three alkyl nitriles. (edf.org)
  • The alkyl nitriles category is comprised of three chemicals: propionitrile (CAS# 107-12-0), butyronitrile (CAS# 109-74-0), and isobutyronitrile (CAS# 78-82-0). (edf.org)
  • Despite finding both high human health hazard and high potential exposures and therefore risks to workers, EPA considers the alkyl nitriles category to be of low priority. (edf.org)
  • Reflection Sapphire Sensitive Nitrile Exam Gloves are a comfortable glove option for dental professionals who are sensitive to latex or the chemical additives used in many common dental office products. (prweb.com)
  • The pyrolysis products of nitrile rubber and chlorophrene are identified and a reaction mechanism is proposed. (mendeley.com)
  • For more information about MICROFLEX MidKnight XTRA, visit https://www.ansell.com/us/en/products/microflex-midknight-xtra-93-862 . (policeone.com)
  • 89.99 //cdn.shopify.com/s/files/1/0073/1797/9225/products/8X797_web01.jpg?v=1564598981 https://gemplers.com/products/gemplers-15-mil-unlined-nitrile-gloves?variant=21291444404313 InStock L 36 pr. (gemplers.com)
  • 2.99 //cdn.shopify.com/s/files/1/0073/1797/9225/products/727G_01_bf88fa14-9a1c-467c-bea0-9d339c0e83d8.jpg?v=1564598981 https://gemplers.com/products/gemplers-15-mil-unlined-nitrile-gloves?variant=21291444535385 InStock L 1 pr. (gemplers.com)
  • 2.99 //cdn.shopify.com/s/files/1/0073/1797/9225/products/727G_01_bf88fa14-9a1c-467c-bea0-9d339c0e83d8.jpg?v=1564598981 https://gemplers.com/products/gemplers-15-mil-unlined-nitrile-gloves?variant=21291444633689 InStock XL 1 pr. (gemplers.com)
  • The polyester open-back seamless knit shell keeps hands cool and comfortable and the nitrile-coated palm offers exceptional protection against punctures and abrasion. (marks.com)
  • Nitrile anions can also be involved in Michael-type additions to activated double bonds and vinylation reactions with a limited number of polarized, unhindered acetylene derivatives. (wikipedia.org)
  • In order to evidence new reactions of prebiotic synthesis in aqueous solution between the S-containing compounds, such as alkanethiols, which can be obtained in gaseous phase during the simulation of the evolution of primitive atmosphere, and the malonic nitriles which are generally considered as important intermediates in the Chemical Evolution, a kinetic study on the eventual reactions of ethanethiol with cyanoacetaldehyde and malononitrile has been carried out. (springer.com)
  • Chitin-supported ruthenium (Ru/chitin) promotes the hydration of nitriles to carboxamides under aqueous conditions. (rsc.org)
  • While only a qualified clinician can diagnose the cause of an allergy or sensitivity, testing has shown that some of these cases involve chemical additives used to manufacture latex, nitrile and chloroprene gloves such as carbamates and thiurams-and rarely Natural Rubber Latex proteins. (prweb.com)
  • The nitrile of benzoic acids was first prepared by Friedrich Wöhler and Justus von Liebig, but due to minimal yield of the synthesis neither physical nor chemical properties were determined nor a structure suggested. (wikipedia.org)