A trace element that plays a role in glucose metabolism. It has the atomic symbol Cr, atomic number 24, and atomic weight 52. According to the Fourth Annual Report on Carcinogens (NTP85-002,1985), chromium and some of its compounds have been listed as known carcinogens.
Chromic acid (H2Cr2O7), dipotassium salt. A compound having bright orange-red crystals and used in dyeing, staining, tanning leather, as bleach, oxidizer, depolarizer for dry cells, etc. Medically it has been used externally as an astringent, antiseptic, and caustic. When taken internally, it is a corrosive poison.
Inorganic compounds that contain sodium as an integral part of the molecule.
A genus of the family BRUCELLACEAE comprising obligately aerobic gram-negative rods with parallel sides and rounded ends.
Inorganic compounds that contain zinc as an integral part of the molecule.
Inorganic compounds that contain potassium as an integral part of the molecule.
Stable chromium atoms that have the same atomic number as the element chromium, but differ in atomic weight. Cr-50, 53, and 54 are stable chromium isotopes.
Carcinogenic substances that are found in the environment.
Tungsten. A metallic element with the atomic symbol W, atomic number 74, and atomic weight 183.85. It is used in many manufacturing applications, including increasing the hardness, toughness, and tensile strength of steel; manufacture of filaments for incandescent light bulbs; and in contact points for automotive and electrical apparatus.
A genus of gram-negative, facultatively anaerobic rods. It is a saprophytic, marine organism which is often isolated from spoiling fish.
A soft, grayish metal with poisonous salts; atomic number 82, atomic weight 207.19, symbol Pb. (Dorland, 28th)
A genus in the family ACETOBACTERACEAE comprised of acetate-oxidizing bacteria.
Inorganic salts of sulfuric acid.
The presence of organisms, or any foreign material that makes a drug preparation impure.
A coenzyme for a number of oxidative enzymes including NADH DEHYDROGENASE. It is the principal form in which RIBOFLAVIN is found in cells and tissues.
Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.
An order of ungulates having an odd number of toes, including the horse, tapir, and rhinoceros. (Dorland, 27th ed)
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.
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).
The aggregate enterprise of manufacturing and technically producing chemicals. (From Random House Unabridged Dictionary, 2d ed)
A group of compounds consisting in part of two rings sharing one atom (usually a carbon) in common.
Phenomena and pharmaceutics of compounds that inhibit the function of agonists (DRUG AGONISM) and inverse agonists (DRUG INVERSE AGONISM) for a specific receptor. On their own, antagonists produce no effect by themselves to a receptor, and are said to have neither intrinsic activity nor efficacy.
Inorganic compounds that contain chromium as an integral part of the molecule.
A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.
Inorganic or organic salts and esters of arsenic acid.
A metallic element with the atomic symbol V, atomic number 23, and atomic weight 50.94. It is used in the manufacture of vanadium steel. Prolonged exposure can lead to chronic intoxication caused by absorption usually via the lungs.
Inorganic compounds that contain calcium as an integral part of the molecule.
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 application of medical knowledge to questions of law.
A genus of asporogenous bacteria isolated from soil that displays a distinctive rod-coccus growth cycle.
Compounds based on imidazolidine dione. Some derivatives are ANTICONVULSANTS.
An increased tendency to acquire CHROMOSOME ABERRATIONS when various processes involved in chromosome replication, repair, or segregation are dysfunctional.
Salts of chromic acid containing the CrO(2-)4 radical.
Metals with high specific gravity, typically larger than 5. They have complex spectra, form colored salts and double salts, have a low electrode potential, are mainly amphoteric, yield weak bases and weak acids, and are oxidizing or reducing agents (From Grant & Hackh's Chemical Dictionary, 5th ed)
An element that is a member of the chalcogen family. It has an atomic symbol S, atomic number 16, and atomic weight [32.059; 32.076]. It is found in the amino acids cysteine and methionine.
A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.
Enzymes which reduce nitro groups (NITRO COMPOUNDS) and other nitrogenous compounds.
Catalyzes the oxidation of GLUTATHIONE to GLUTATHIONE DISULFIDE in the presence of NADP+. Deficiency in the enzyme is associated with HEMOLYTIC ANEMIA. Formerly listed as EC 1.6.4.2.
A purine nucleoside that has guanine linked by its N9 nitrogen to the C1 carbon of ribose. It is a component of ribonucleic acid and its nucleotides play important roles in metabolism. (From Dorland, 28th ed)
A metallic element with the atomic symbol Mo, atomic number 42, and atomic weight 95.94. It is an essential trace element, being a component of the enzymes xanthine oxidase, aldehyde oxidase, and nitrate reductase. (From Dorland, 27th ed)
Diseases caused by factors involved in one's employment.
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)
The univalent radical OH. Hydroxyl radical is a potent oxidizing agent.
A species of gram-negative, rod-shaped bacteria belonging to the K serogroup of ESCHERICHIA COLI. It lives as a harmless inhabitant of the human LARGE INTESTINE and is widely used in medical and GENETIC RESEARCH.
Tests of chemical substances and physical agents for mutagenic potential. They include microbial, insect, mammalian cell, and whole animal tests.
Nutritional factor found in milk, eggs, malted barley, liver, kidney, heart, and leafy vegetables. The richest natural source is yeast. It occurs in the free form only in the retina of the eye, in whey, and in urine; its principal forms in tissues and cells are as FLAVIN MONONUCLEOTIDE and FLAVIN-ADENINE DINUCLEOTIDE.
Detection of drugs that have been abused, overused, or misused, including legal and illegal drugs. Urine screening is the usual method of detection.
A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.
An excited state of molecular oxygen generated photochemically or chemically. Singlet oxygen reacts with a variety of biological molecules such as NUCLEIC ACIDS; PROTEINS; and LIPIDS; causing oxidative damages.
Proteins found in any species of bacterium.
Inorganic compounds that contain the OH- group.
A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)
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.
The larger air passages of the lungs arising from the terminal bifurcation of the TRACHEA. They include the largest two primary bronchi which branch out into secondary bronchi, and tertiary bronchi which extend into BRONCHIOLES and PULMONARY ALVEOLI.
Nanoparticles produced from metals whose uses include biosensors, optics, and catalysts. In biomedical applications the particles frequently involve the noble metals, especially gold and silver.
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.
Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.
Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.
Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.
Any technique by which an unknown color is evaluated in terms of standard colors. The technique may be visual, photoelectric, or indirect by means of spectrophotometry. It is used in chemistry and physics. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
Chemicals and substances that impart color including soluble dyes and insoluble pigments. They are used in INKS; PAINTS; and as INDICATORS AND REAGENTS.
A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.
Substances that increase the risk of NEOPLASMS in humans or animals. Both genotoxic chemicals, which affect DNA directly, and nongenotoxic chemicals, which induce neoplasms by other mechanism, are included.
A highly-sensitive (in the picomolar range, which is 10,000-fold more sensitive than conventional electrophoresis) and efficient technique that allows separation of PROTEINS; NUCLEIC ACIDS; and CARBOHYDRATES. (Segen, Dictionary of Modern Medicine, 1992)
The rate dynamics in chemical or physical systems.
The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.
Refuse liquid or waste matter carried off by sewers.
The functional hereditary units of BACTERIA.
The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).
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.
Nucleotide sequences of a gene that are involved in the regulation of GENETIC TRANSCRIPTION.
A species of rod-shaped bacteria that is a common soil saprophyte. Its spores are widespread and multiplication has been observed chiefly in foods. Contamination may lead to food poisoning.
A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.
In bacteria, a group of metabolically related genes, with a common promoter, whose transcription into a single polycistronic MESSENGER RNA is under the control of an OPERATOR REGION.
The measurement of radiation by photography, as in x-ray film and film badge, by Geiger-Mueller tube, and by SCINTILLATION COUNTING.
Deoxyribonucleic acid that makes up the genetic material of bacteria.
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.
The cell center, consisting of a pair of CENTRIOLES surrounded by a cloud of amorphous material called the pericentriolar region. During interphase, the centrosome nucleates microtubule outgrowth. The centrosome duplicates and, during mitosis, separates to form the two poles of the mitotic spindle (MITOTIC SPINDLE APPARATUS).
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Proteins obtained from ESCHERICHIA COLI.
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Centrifugation with a centrifuge that develops centrifugal fields of more than 100,000 times gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
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)
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.
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.
Tumors or cancer of the LUNG.
The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.
Established cell cultures that have the potential to propagate indefinitely.
A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
Relating to the size of solids.
Elements of limited time intervals, contributing to particular results or situations.
A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.
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.
Cell changes manifested by escape from control mechanisms, increased growth potential, alterations in the cell surface, karyotypic abnormalities, morphological and biochemical deviations from the norm, and other attributes conferring the ability to invade, metastasize, and kill.
A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.
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.
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.
The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
The relationship between the dose of an administered drug and the response of the organism to the drug.
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.
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
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.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
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.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.
Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.
Substances that reduce the growth or reproduction of BACTERIA.
A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.

Chromate efflux by means of the ChrA chromate resistance protein from Pseudomonas aeruginosa. (1/216)

Everted membrane vesicles of Pseudomonas aeruginosa PAO1 harboring plasmid pCRO616, expressing the ChrA chromate resistance protein, accumulated four times more (51)CrO(4)(2-) than vesicles from plasmidless cells, indicating that a chromate efflux system functions in the resistant strain. Chromate uptake showed saturation kinetics with an apparent K(m) of 0.12 mM chromate and a V(max) of 0. 5 nmol of chromate/min per mg of protein. Uptake of chromate by vesicles was dependent on NADH oxidation and was abolished by energy inhibitors and by the chromate analog sulfate. The mechanism of resistance to chromate determined by ChrA appears to be based on the active efflux of chromate driven by the membrane potential.  (+info)

Mortality among aircraft manufacturing workers. (2/216)

OBJECTIVES: To evaluate the risk of cancer and other diseases among workers engaged in aircraft manufacturing and potentially exposed to compounds containing chromate, trichloroethylene (TCE), perchloroethylene (PCE), and mixed solvents. METHODS: A retrospective cohort mortality study was conducted of workers employed for at least 1 year at a large aircraft manufacturing facility in California on or after 1 January 1960. The mortality experience of these workers was determined by examination of national, state, and company records to the end of 1996. Standardised mortality ratios (SMRs) were evaluated comparing the observed numbers of deaths among workers with those expected in the general population adjusting for age, sex, race, and calendar year. The SMRs for 40 cause of death categories were computed for the total cohort and for subgroups defined by sex, race, position in the factory, work duration, year of first employment, latency, and broad occupational groups. Factory job titles were classified as to likely use of chemicals, and internal Poisson regression analyses were used to compute mortality risk ratios for categories of years of exposure to chromate, TCE, PCE, and mixed solvents, with unexposed factory workers serving as referents. RESULTS: The study cohort comprised 77,965 workers who accrued nearly 1.9 million person-years of follow up (mean 24.2 years). Mortality follow up, estimated as 99% complete, showed that 20,236 workers had died by 31 December 1996, with cause of death obtained for 98%. Workers experienced low overall mortality (all causes of death SMR 0.83) and low cancer mortality (SMR 0.90). No significant increases in risk were found for any of the 40 specific cause of death categories, whereas for several causes the numbers of deaths were significantly below expectation. Analyses by occupational group and specific job titles showed no remarkable mortality patterns. Factory workers estimated to have been routinely exposed to chromate were not at increased risk of total cancer (SMR 0.93) or of lung cancer (SMR 1.02). Workers routinely exposed to TCE, PCE, or a mixture of solvents also were not at increased risk of total cancer (SMRs 0.86, 1.07, and 0.89, respectively), and the numbers of deaths for specific cancer sites were close to expected values. Slight to moderately increased rates of non-Hodgkin's lymphoma were found among workers exposed to TCE or PCE, but none was significant. A significant increase in testicular cancer was found among those with exposure to mixed solvents, but the excess was based on only six deaths and could not be linked to any particular solvent or job activity. Internal cohort analyses showed no significant trends of increased risk for any cancer with increasing years of exposure to chromate or solvents. CONCLUSIONS: The results from this large scale cohort study of workers followed up for over 3 decades provide no clear evidence that occupational exposures at the aircraft manufacturing factory resulted in increases in the risk of death from cancer or other diseases. Our findings support previous studies of aircraft workers in which cancer risks were generally at or below expected levels.  (+info)

Purification to homogeneity and characterization of a novel Pseudomonas putida chromate reductase. (3/216)

Cr(VI) (chromate) is a widespread environmental contaminant. Bacterial chromate reductases can convert soluble and toxic chromate to the insoluble and less toxic Cr(III). Bioremediation can therefore be effective in removing chromate from the environment, especially if the bacterial propensity for such removal is enhanced by genetic and biochemical engineering. To clone the chromate reductase-encoding gene, we purified to homogeneity (>600-fold purification) and characterized a novel soluble chromate reductase from Pseudomonas putida, using ammonium sulfate precipitation (55 to 70%), anion-exchange chromatography (DEAE Sepharose CL-6B), chromatofocusing (Polybuffer exchanger 94), and gel filtration (Superose 12 HR 10/30). The enzyme activity was dependent on NADH or NADPH; the temperature and pH optima for chromate reduction were 80 degrees C and 5, respectively; and the K(m) was 374 microM, with a V(max) of 1.72 micromol/min/mg of protein. Sulfate inhibited the enzyme activity noncompetitively. The reductase activity remained virtually unaltered after 30 min of exposure to 50 degrees C; even exposure to higher temperatures did not immediately inactivate the enzyme. X-ray absorption near-edge-structure spectra showed quantitative conversion of chromate to Cr(III) during the enzyme reaction.  (+info)

Apoptosis and P53 induction in human lung fibroblasts exposed to chromium (VI): effect of ascorbate and tocopherol. (4/216)

Some forms of hexavalent chromium [Cr(VI)] are known to cause damage to respiratory tract tissue, and are thought to be human lung carcinogens. Because Cr(VI) is mutagenic and carcinogenic at doses that evoke cell toxicity, the objective of these experiments was to examine the effect of Cr(VI) on the growth, survival, and mode of cell death in normal human lung fibroblasts (HLF cells). DNA adduct formation was monitored as a marker for bioavailability of genotoxic chromium. We also examined the modulation of these endpoints by vitamins C and E. Long-term Cr(VI) exposures were employed, which decreased clonogenic cell survival by 25% to 95% in a dose-dependent manner. The predominant cellular response to Cr(VI) was growth arrest. We found that Cr(VI) caused up to 20% of HLF cells to undergo apoptosis, and documented apoptotic morphology and the phagocytosis of apoptotic bodies by neighboring cells. P53 levels increased 4- to 6-fold in chromium-treated cells. In contrast with previous studies using CHO cells, the present study using HLFs found that pretreatment with either vitamin C or E did not exhibit a significant effect on Cr-induced apoptosis or clonogenic survival. In addition, pretreatment with vitamin C did not affect the p53 induction observed after chromium treatment. Neither vitamin had any effect on Cr-DNA adduct formation. These data indicate that although pretreatment with vitamin C or E alters the spectrum of cellular and/or genetic lesions induced by chromium(VI), neither vitamin altered the initiation or progression of apoptosis in diploid human lung cells.  (+info)

Organization-dependent effects of toxic bivalent ions microtubule assembly and glycolysis. (5/216)

The effects of bivalent ions on tubulin dynamics and the upper phase of glycolysis were investigated at different organization levels in vitro. Cu2+, Cd2+, Hg2+ and CrO4(2-) inhibit the tubulin polymerization at an IC50 of 14-24 microM with high cooperativity and also induce microtubule disassembly. The apparent binding constants of the ions to tubulin, estimated by fluorescence quenching, vary between 6 and 28 microM. BIAcore measurements for tubulin-tubulin interaction suggest that the presence of Cu2+ affects neither koff nor kon, but the amount of the bound tubulin. While the inhibitory effect of Cu2+ on tubulin polymerization is partially abolished by cross-linking of microtubules with substoichiometric amounts of phosphofructokinase or decoration of tubules with cytosolic proteins, in the presence of kinase but not with cytosolic proteins the tubules are resistant to CrO4(2-). No inhibitory effect of Cu2+ or CrO4(2-) on microtubule assembly was detected in the MAP-containing cytosolic fraction. Electron microscopy revealed that tubules assembled in the presence of Cu2+ or CrO4(2-) ions contain aggregates of thread-like oligomers that are less conspicuous in the presence of cytosolic proteins. Cu2+, Cd2+, and Hg2+ inhibit the glycolytic flux in the cytosolic fraction characterized at equilibrium by an IC50 of 10-14 microM with high cooperativity. Tubulin diminishes the inhibitory effect of the cations. These data indicate that the responses elicited by the bivalent ions are highly dependent on the supramolecular organization of the systems.  (+info)

Activation of JNK, p38 and ERK mitogen-activated protein kinases by chromium(VI) is mediated through oxidative stress but does not affect cytotoxicity. (6/216)

In this study we have explored the involvement of oxidative stress in Cr(VI)-induced JNK, p38 and ERK signaling pathways and their effects on Cr(VI) cytotoxicity in human non-small cell lung carcinoma CL3 cells. Exposure to K(2)Cr(2)O(7) markedly activated JNK and p38 and moderately activated ERK in a dose- (10-80 microM) and time-dependent (1-12 h) manner. The activated p38 decreased markedly and rapidly and the activated JNK decreased gradually when Cr(VI) was removed from the medium. Post-incubation of Cr(VI)-treated cells with H(2)O(2) increased the activities of JNK and p38, but not ERK. Co-administering Cr(VI) with 3-amino-1,2, 4-triazole (3AT), a catalase inhibitor, enhanced p38 activation, but did not influence JNK and ERK activation by Cr(VI). Conversely, co-administering Cr(VI) with mannitol, a hydroxyl radical scavenger and a Cr(V) chelator, reduced p38 activation and increased JNK and ERK activation by Cr(VI). These results indicate that p38 activation by Cr(VI) is positively correlated with oxidative stress, while JNK activity can be enhanced by either a quencher (mannitol) or activator (H(2)O(2)) of redox reactions in Cr(VI)-exposed CL3 cells. However, both 3AT and mannitol reduced the cytotoxicity of Cr(VI), but H(2)O(2) did not. The JNK activated by Cr(VI) was decreased (approximately 50%) by expression of a kinase-defective form of MKK7 (MKK7A) but not that of MKK4 (MKK4KR), suggesting that activation of JNK by Cr(VI) is mediated through MKK7. SB202190, a specific inhibitor of p38, markedly decreased JNK but did not change ERK activation by Cr(VI). PD98059, a specific inhibitor of ERK kinases MKK1/2, blocked ERK and p38 but did not alter JNK activation by Cr(VI). Neither the specific kinase inhibitors nor expression of MKK7A altered Cr(VI)-induced cytotoxicity. Together, these results suggest that activation of the JNK, p38 and ERK pathways by Cr(VI) is mediated through diverse redox mechanisms, yet their activation does not correlate with Cr(VI) cytotoxicity.  (+info)

Cyclosporin A inhibits chromium(VI)-induced apoptosis and mitochondrial cytochrome c release and restores clonogenic survival in CHO cells. (7/216)

A variety of key events in the molecular apoptotic pathway involve the mitochondria. Cyclosporin A (csA) affects the mitochondria by inhibiting the mitochondrial permeability transition (MPT), thereby preventing disruption of the transmembrane potential. The role of the MPT in apoptosis is not fully understood, but inhibition of the MPT may prevent the release of mitochondrial caspase activators, such as cytochrome c (cyt c), into the cytosol. Certain hexavalent chromium [Cr(VI)] compounds are known occupational respiratory tract toxins and carcinogens. We have previously shown that these compounds induce apoptosis as a predominant mode of cell death and that this effect can be observed in cell culture using soluble Cr(VI). We show here that Cr(VI)-induced apoptosis in Chinese hamster ovary (CHO) cells involves disruption of mitochondrial stability. Using a cyt c-specific monoclonal antibody, we observed a dose-dependent release of mitochondrial cyt c in cytosolic extracts of CHO cells exposed to apoptogenic doses of sodium chromate. Co-treatment of these cells with csA inhibited the release of cyt c and abrogated Cr(VI)-induced apoptosis as determined by a reduction in internucleosomal DNA fragmentation. Co-treatment with csA also markedly increased clonogenic survival of Cr(VI)-treated CHO cells. In contrast, the general caspase inhibitor Z-VAD-FMK markedly inhibited most of the morphological and biochemical parameters of apoptosis but did not prevent cyt c release and did not increase clonogenic survival. These results suggest that the MPT plays an important role in the regulation of mitochondrial cyt c release and that this may be a critical point in the apoptotic pathway in which cells are irreversibly committed to death.  (+info)

Chromate reduction by a pseudomonad isolated from a site contaminated with chromated copper arsenate. (8/216)

A pseudomonad (CRB5) isolated from a decommissioned wood preservation site reduced toxic chromate [Cr(VI)] to an insoluble Cr(III) precipitate under aerobic and anaerobic conditions. CRB5 tolerated up to 520 mg of Cr(VI) liter(-1) and reduced chromate in the presence of copper and arsenate. Under anaerobic conditions it also reduced Co(III) and U(VI), partially internalizing each metal. Metal precipitates were also found on the surface of the outer membrane and (sometimes) on a capsule. The results showed that chromate reduction by CRB5 was mediated by a soluble enzyme that was largely contained in the cytoplasm but also found outside of the cells. The crude reductase activity in the soluble fraction showed a K(m) of 23 mg liter(-1) (437 microM) and a V(max) of 0.98 mg of Cr h(-1) mg of protein(-1) (317 nmol min(-1) mg of protein(-1)). Minor membrane-associated Cr(VI) reduction under anaerobiosis may account for anaerobic reduction of chromate under nongrowth conditions with an organic electron donor present. Chromate reduction under both aerobic and anaerobic conditions may be a detoxification strategy for the bacterium which could be exploited to bioremediate chromate-contaminated or other toxic heavy metal-contaminated environments.  (+info)

Causes of Chromosomal Instability:

1. Genetic mutations: Mutations in genes that regulate the cell cycle or chromosome segregation can lead to CIN.
2. Environmental factors: Exposure to certain environmental agents such as radiation and certain chemicals can increase the risk of developing CIN.
3. Errors during DNA replication: Mistakes during DNA replication can also lead to CIN.

Types of Chromosomal Instability:

1. Aneuploidy: Cells with an abnormal number of chromosomes, either more or fewer than the normal diploid number (46 in humans).
2. Structural changes: Deletions, duplications, inversions, translocations, and other structural changes can occur in the chromosomes.
3. Unstable chromosome structures: Chromosomes with abnormal shapes or structures, such as telomere shortening, centromere instability, or chromosome breaks, can also lead to CIN.

Effects of Chromosomal Instability:

1. Cancer: CIN can increase the risk of developing cancer by disrupting normal cellular processes and leading to genetic mutations.
2. Aging: CIN can contribute to aging by shortening telomeres, which are the protective caps at the ends of chromosomes that help maintain their stability.
3. Neurodegenerative diseases: CIN has been implicated in the development of certain neurodegenerative diseases such as Alzheimer's and Parkinson's.
4. Infertility: CIN can lead to infertility by disrupting normal meiotic recombination and chromosome segregation during gametogenesis.

Detection and Diagnosis of Chromosomal Instability:

1. Karyotyping: This is a technique used to visualize the entire set of chromosomes in a cell. It can help identify structural abnormalities such as deletions, duplications, or translocations.
2. Fluorescence in situ hybridization (FISH): This technique uses fluorescent probes to detect specific DNA sequences or proteins on chromosomes. It can help identify changes in chromosome structure or number.
3. Array comparative genomic hybridization (aCGH): This technique compares the genetic material of a sample to a reference genome to identify copy number changes.
4. Next-generation sequencing (NGS): This technique can identify point mutations and other genetic changes in DNA.

Treatment and Management of Chromosomal Instability:

1. Cancer treatment: Depending on the type and stage of cancer, treatments such as chemotherapy, radiation therapy, or surgery may be used to eliminate cancer cells with CIN.
2. Prenatal testing: Pregnant women with a family history of CIN can undergo prenatal testing to detect chromosomal abnormalities in their fetuses.
3. Genetic counseling: Individuals with a family history of CIN can consult with a genetic counselor to discuss risk factors and potential testing options.
4. Lifestyle modifications: Making healthy lifestyle choices such as maintaining a balanced diet, exercising regularly, and not smoking can help reduce the risk of developing cancer and other diseases associated with CIN.

In conclusion, chromosomal instability is a common feature of many human diseases, including cancer, and can be caused by a variety of factors. The diagnosis and management of CIN require a multidisciplinary approach that includes cytogenetic analysis, molecular diagnostics, and clinical evaluation. Understanding the causes and consequences of CIN is crucial for developing effective therapies and improving patient outcomes.

1. Asbestosis: a lung disease caused by inhaling asbestos fibers.
2. Carpal tunnel syndrome: a nerve disorder caused by repetitive motion and pressure on the wrist.
3. Mesothelioma: a type of cancer caused by exposure to asbestos.
4. Pneumoconiosis: a lung disease caused by inhaling dust from mining or other heavy industries.
5. Repetitive strain injuries: injuries caused by repetitive motions, such as typing or using vibrating tools.
6. Skin conditions: such as skin irritation and dermatitis caused by exposure to chemicals or other substances in the workplace.
7. Hearing loss: caused by loud noises in the workplace.
8. Back injuries: caused by lifting, bending, or twisting.
9. Respiratory problems: such as asthma and other breathing difficulties caused by exposure to chemicals or dust in the workplace.
10. Cancer: caused by exposure to carcinogens such as radiation, certain chemicals, or heavy metals in the workplace.

Occupational diseases can be difficult to diagnose and treat, as they often develop gradually over time and may not be immediately attributed to the work environment. In some cases, these diseases may not appear until years after exposure has ended. It is important for workers to be aware of the potential health risks associated with their job and take steps to protect themselves, such as wearing protective gear, following safety protocols, and seeking regular medical check-ups. Employers also have a responsibility to provide a safe work environment and follow strict regulations to prevent the spread of occupational diseases.

There are several types of aneuploidy, including:

1. Trisomy: This is the presence of an extra copy of a chromosome. For example, Down syndrome is caused by an extra copy of chromosome 21 (trisomy 21).
2. Monosomy: This is the absence of a chromosome.
3. Mosaicism: This is the presence of both normal and abnormal cells in the body.
4. Uniparental disomy: This is the presence of two copies of a chromosome from one parent, rather than one copy each from both parents.

Aneuploidy can occur due to various factors such as errors during cell division, exposure to certain chemicals or radiation, or inheritance of an abnormal number of chromosomes from one's parents. The risk of aneuploidy increases with age, especially for women over the age of 35, as their eggs are more prone to errors during meiosis (the process by which egg cells are produced).

Aneuploidy can be diagnosed through various methods such as karyotyping (examining chromosomes under a microscope), fluorescence in situ hybridization (FISH) or quantitative PCR. Treatment for aneuploidy depends on the underlying cause and the specific health problems it has caused. In some cases, treatment may involve managing symptoms, while in others, it may involve correcting the genetic abnormality itself.

In summary, aneuploidy is a condition where there is an abnormal number of chromosomes present in a cell, which can lead to various developmental and health problems. It can occur due to various factors and can be diagnosed through different methods. Treatment depends on the underlying cause and the specific health problems it has caused.

There are several types of lung neoplasms, including:

1. Adenocarcinoma: This is the most common type of lung cancer, accounting for approximately 40% of all lung cancers. It is a malignant tumor that originates in the glands of the respiratory tract and can be found in any part of the lung.
2. Squamous cell carcinoma: This type of lung cancer accounts for approximately 25% of all lung cancers and is more common in men than women. It is a malignant tumor that originates in the squamous cells lining the airways of the lungs.
3. Small cell lung cancer (SCLC): This is a highly aggressive form of lung cancer that accounts for approximately 15% of all lung cancers. It is often found in the central parts of the lungs and can spread quickly to other parts of the body.
4. Large cell carcinoma: This is a rare type of lung cancer that accounts for only about 5% of all lung cancers. It is a malignant tumor that originates in the large cells of the respiratory tract and can be found in any part of the lung.
5. Bronchioalveolar carcinoma (BAC): This is a rare type of lung cancer that originates in the cells lining the airways and alveoli of the lungs. It is more common in women than men and tends to affect older individuals.
6. Lymphangioleiomyomatosis (LAM): This is a rare, progressive, and often fatal lung disease that primarily affects women of childbearing age. It is characterized by the growth of smooth muscle-like cells in the lungs and can lead to cysts, lung collapse, and respiratory failure.
7. Hamartoma: This is a benign tumor that originates in the tissue of the lungs and is usually found in children. It is characterized by an overgrowth of normal lung tissue and can be treated with surgery.
8. Secondary lung cancer: This type of cancer occurs when cancer cells from another part of the body spread to the lungs through the bloodstream or lymphatic system. It is more common in people who have a history of smoking or exposure to other carcinogens.
9. Metastatic cancer: This type of cancer occurs when cancer cells from another part of the body spread to the lungs through the bloodstream or lymphatic system. It is more common in people who have a history of smoking or exposure to other carcinogens.
10. Mesothelioma: This is a rare and aggressive form of cancer that originates in the lining of the lungs or abdomen. It is caused by asbestos exposure and can be treated with surgery, chemotherapy, and radiation therapy.

Lung diseases can also be classified based on their cause, such as:

1. Infectious diseases: These are caused by bacteria, viruses, or other microorganisms and can include pneumonia, tuberculosis, and bronchitis.
2. Autoimmune diseases: These are caused by an overactive immune system and can include conditions such as sarcoidosis and idiopathic pulmonary fibrosis.
3. Genetic diseases: These are caused by inherited mutations in genes that affect the lungs and can include cystic fibrosis and primary ciliary dyskinesia.
4. Environmental diseases: These are caused by exposure to harmful substances such as tobacco smoke, air pollution, and asbestos.
5. Radiological diseases: These are caused by exposure to ionizing radiation and can include conditions such as radiographic breast cancer and lung cancer.
6. Vascular diseases: These are caused by problems with the blood vessels in the lungs and can include conditions such as pulmonary embolism and pulmonary hypertension.
7. Tumors: These can be benign or malignant and can include conditions such as lung metastases and lung cancer.
8. Trauma: This can include injuries to the chest or lungs caused by accidents or other forms of trauma.
9. Congenital diseases: These are present at birth and can include conditions such as bronchopulmonary foregut malformations and congenital cystic adenomatoid malformation.

Each type of lung disease has its own set of symptoms, diagnosis, and treatment options. It is important to seek medical attention if you experience any persistent or severe respiratory symptoms, as early diagnosis and treatment can improve outcomes and quality of life.

Explanation: Neoplastic cell transformation is a complex process that involves multiple steps and can occur as a result of genetic mutations, environmental factors, or a combination of both. The process typically begins with a series of subtle changes in the DNA of individual cells, which can lead to the loss of normal cellular functions and the acquisition of abnormal growth and reproduction patterns.

Over time, these transformed cells can accumulate further mutations that allow them to survive and proliferate despite adverse conditions. As the transformed cells continue to divide and grow, they can eventually form a tumor, which is a mass of abnormal cells that can invade and damage surrounding tissues.

In some cases, cancer cells can also break away from the primary tumor and travel through the bloodstream or lymphatic system to other parts of the body, where they can establish new tumors. This process, known as metastasis, is a major cause of death in many types of cancer.

It's worth noting that not all transformed cells will become cancerous. Some forms of cellular transformation, such as those that occur during embryonic development or tissue regeneration, are normal and necessary for the proper functioning of the body. However, when these transformations occur in adult tissues, they can be a sign of cancer.

See also: Cancer, Tumor

Word count: 190

... or chromat, and their derived terms, may refer to: Chromate and dichromate, ions Monochromate, an ion Trichromate, an ... This disambiguation page lists articles associated with the title Chromate. If an internal link led you here, you may wish to ... ion Tetrachromate, an ion Chromate conversion coating, a method for passivating metals Monochromacy (monochromate) having one ...
... is an inorganic compound with the formula CaCrO4, i.e. the chromate salt of calcium. It is a bright yellow ... Calcium chromate is formed from the salt metathesis reaction of sodium chromate and calcium chloride: Na2CrO4 + CaCl2 → CaCrO4 ... The compound is occasionally used as a yellow inorganic pigment, or a corrosion inhibitor as part of the chromate conversion ... Occupational Safety And Health Guideline For Calcium Chromate Archived August 8, 2007, at the Wayback Machine IARC (2012) [17- ...
... is the inorganic compound with the formula K2CrO4. This yellow solid is the potassium salt of the chromate ... Tarapacaite is the natural, mineral form of potassium chromate. It occurs very rarely and until now is known from only few ... When treated with lead(II) nitrate, it gives an orange-yellow precipitate, lead(II) chromate. Unlike the less expensive sodium ... It is a common laboratory chemical, whereas sodium chromate is important industrially. Two crystalline forms are known, both ...
... or cesium chromate is an inorganic compound with the formula Cs2CrO4. It is a yellow crystalline solid that is ... Caesium chromate is mainly obtained from the reaction of chromium(VI) oxide with caesium carbonate, wherein carbon dioxide gas ... Therein, caesium vapour was produced by reaction of caesium chromate with silicon, boron, or titanium as reducing agents. The ... ISBN 0-8493-0462-8.. Liebhafsky, H. A.; Winslow, A. F. (1947), "Cesium Chromate Photo‐Tube Pellets", Journal of Applied Physics ...
... is the inorganic compound with the formula CdCrO4. It is relevant to chromate conversion coating, which is ... Chromate species take on their distinctive yellow color when coated. NIOSH Pocket Guide to Chemical Hazards. "#0087". National ... In conversion coating chromate reacts with these metals to prevent corrosion, retain electrical conductivity, and provide a ...
Chromate and dichromate As with other Cr(VI) compounds, sodium chromate is carcinogenic. The compound is also corrosive and ... "Sodium chromate". inchem. Retrieved 2008-06-20. Record of Sodium chromate in the GESTIS Substance Database of the Institute for ... even 350 C in the corresponding potassium chromate system). Subsequent to its formation, the chromate salt is converted to ... Sodium chromate is the inorganic compound with the formula Na2CrO4. It exists as a yellow hygroscopic solid, which can form ...
... can also be synthesized by using neutral potassium chromate (K2CrO4) and zinc sulfate (ZnSO4), which forms a ... Zinc chromate, ZnCrO4, is a chemical compound containing the chromate anion, appearing as odorless yellow powder or yellow- ... Recent studies have shown that not only is zinc chromate highly toxic, it is also a carcinogen. Exposure to zinc chromate can ... "ZINC CHROMATE - CAMEO Chemicals". Retrieved 24 March 2011. "OHSA Guideline for Zinc Chromate". Occupational Safety and Health ...
... and aqueous chromate ions, and tend to react via redox reactions to liberate chromium(IV). Chromate esters are the key reactive ... A chromate ester is a chemical structure that contains a chromium atom (symbol Cr) in a +6 oxidation state that is connected ... Chromate esters of allyl alcohols may isomerize via formal [3,3]-sigmatropic shift to give rearranged enone products. An ... The Cr itself is in its chromate form, with several oxygens attached, and the Cr-O-C attachment makes this chemical group ...
... is a chemical compound, with the formula SrCrO4. Strontium chromate is prepared from the reaction of ... Chromates, Strontium compounds, All stub articles, Inorganic compound stubs). ... strontium chloride with sodium chromate, or from a reaction between strontium carbonate with sodium dichromate. Corrosion ...
"Ammonium chromate". Sigma-Aldrich Co., Ammonium chromate. Retrieved on 28-04-2014. Information preview for Ammonium chromate, ... Ammonium chromate is a salt with the formula (NH4)2CrO4. It forms yellow, monoclinic crystals; made from ammonium hydroxide and ... It is often used in photography, textile printing, and fixing chromate dyes on wool. It is also used as an analytical reagent, ...
Adding barium chromate enhances the life of the bath by adding to the chromic acid concentration. Barium chromate is an ... Using zinc chromate as a standard, it was discovered that barium chromate is both genotoxic and cytotoxic. The cytotoxicity was ... Barium chromate is toxic. Chromates, when pulverized and inhaled, are carcinogens. John Rumble (June 18, 2018). CRC Handbook of ... Barium chromate, named barium tetraoxochromate(VI) by the IUPAC, is a yellow sand like powder with the formula BaCrO4. It is a ...
This chromate can be manufactured as a powder. Before 1940, the literature about magnesium chromate and its hydrates was sparse ... "Magnesium chromate hydrate, 99.8% (metals basis)". Us.vwr.com. Retrieved 2013-07-16. "Item # MG-401, Heavy Magnesium Chromate ... Hill, Arthur E.; Soth, Glenn C.; Ricci, John E. (1940). "The Systems Magnesium Chromate-Water and Ammonium Chromate-Water from ... Magnesium chromate is a chemical compound, with the formula MgCrO4. It is a yellow, odorless, water-soluble solid with several ...
... is usually produced by the salt metathesis reaction of potassium chromate (K2CrO4) and silver nitrate (AgNO3) ... Robbins, David J.; Day, Peter (1977-09-01). "Why is silver chromate red? The 4·2 K polarized electronic spectrum of chromate in ... of silver chromate is rather unlike other chromates which are typically yellow to yellowish orange in appearance. This ... As for all chromates, which are chromium(VI) species, the compound poses a hazard of toxicity, carcinogenicity and genotoxicity ...
... can be produced by treating sodium chromate with lead salts such as lead(II) nitrate or by combining lead(II ... Lead chromate is treated with great care in its manufacture, the main concerns being dust of the chromate precursor. "[E] ... Crocoite Iranite Safety (MSDS) data for lead chromate Chemical Profile for lead chromate J.T. Baker MSDS Quareni, S.; de Pieri ... Two polymorphs of lead chromate are known, orthorhombic and the more stable monoclinic form. Monoclinic lead chromate is used ...
The Hagdale Chromate Railway was a 2 ft 6 in (762 mm) narrow-gauge railway on the Isle of Unst, in the Shetland Islands. Built ...
... chromate is 15.9 K. Above 700 °C, europium(III) chromate begins to decompose into europium chromite (EuCrO3). 2EuCrO4 → 2 ... Europium(III) chromate is an chemical compound composed of europium, chromium and oxygen with europium in the +3 oxidation ... To obtain europium(III) chromate, an equimolar solution of europium(III) acetate and chromium(IV) oxide is dried in a vacuum at ... Another way to obtain europium(III) chromate is by reacting stoichiometric amounts of europium(III) nitrate hexahydrate and ...
Nickel chromate is dark in colour, unlike most other chromates which are yellow. The infrared spectrum of nickel chromate show ... Precipitates of Ni2+ ions with chromate produce a brown substance that contains water. The structure of nickel chromate is the ... Nickel(II) chromate can be formed in the lab by heating a mixture of chromium(III) oxide and nickel oxide at between 700 °C and ... Nickel(II) chromate (NiCrO4) is an acid-soluble compound, red-brown in color, with high tolerances for heat. It and the ions ...
... is the iron(III) salt of chromic acid with the chemical formula Fe2(CrO4)3. Iron(III) chromate was ... It may be formed by the reaction of potassium chromate and iron(III) nitrate. This reaction forms iron(III) chromate and ... Chromates, Iron(III) compounds, Oxidizing agents, All stub articles, Inorganic compound stubs). ...
In an aqueous solution, chromate and dichromate ions can be interconvertible. potassium chromate potassium dichromate Chromates ... Normally the chromate solution is further processed to make chromium metal, but a chromate salt may be obtained directly from ... Chromates and dichromates are used in chrome plating to protect metals from corrosion and to improve paint adhesion. Chromate ... Chromate salts contain the chromate anion, CrO2− 4. Dichromate salts contain the dichromate anion, Cr 2O2− 7. They are ...
... depending on the chromate layer's thickness. The protective effect of chromate coatings on zinc is indicated by color, ... "Effects of chromate and chromate conversion coatings on corrosion of aluminum alloy 2024-T3". Surface and Coatings Technology, ... "Evaluation of chromate passivation and chromate conversion coating on 55% Al-Zn coated steel". Surface and Coatings Technology ... For aluminum, the chromate conversion bath can be simply a solution of chromic acid. The process is rapid (1-5 min), requires a ...
... is an alkoxide with the formula CrO2(OC(CH3)3)2. It is prepared by treatment of t-butanol with chromic ... Like other forms of hexavalent chromium, di-tert-butyl chromate is classified as a potential carcinogen by the United States ... Amirthalingam, V.; Grant, D. F.; Senol, A. (1972). "The crystal structure and absolute configuration of cedryl chromate". Acta ... Freeman, Fillmore (2001-04-15), "Di-tert-butyl Chromate", Encyclopedia of Reagents for Organic Synthesis, John Wiley & Sons, ...
0138". National Institute for Occupational Safety and Health (NIOSH). "Chromic acid and chromates". Immediately Dangerous to ... Hexavalent chromium compounds (including chromium trioxide, chromic acids, chromates, chlorochromates) are toxic and ... "Equilibria of chromate(VI) species in acid medium and ab initio studies of these species". Polyhedron. 16 (21): 3835-3846. doi: ... Chromates, Oxidizing agents, Oxidizing acids, Mineral acids, Transition metal oxoacids). ...
"Ammonium chromate". pubchem.ncbi.nlm.nih.gov. Retrieved 2022-11-22. PubChem. "Ammonium Chloride". pubchem.ncbi.nlm.nih.gov. ... "Barium chromate". pubchem.ncbi.nlm.nih.gov. Retrieved 2022-11-22. PubChem. "Barium ferrite". pubchem.ncbi.nlm.nih.gov. ... NH4Br Ammonium chromate - [NH4]2CrO4 Ammonium cerium(IV) nitrate - [NH4]2[Ce(NO3)6] Ammonium cerium(IV) sulfate - [NH4]4[Ce(SO4 ... BaCl2 Barium chromate - BaCrO4 Barium ferrate - BaFeO4 Barium ferrite - BaFe12O19 Barium fluoride - BaF2 Barium hydroxide - Ba( ...
Lead molybdate (wulfenite) co-precipitated with lead chromate and lead sulfate is a bright-orange pigment used with ceramics ... Molybdates are weaker oxidants than chromates. They tend to form structurally complex oxyanions by condensation at lower pH ...
Chromates and molybdates produce the same reaction. The major drawback of the test is the deterioration of stock solution of ... Reacting a Diphenylcarbazide with Chromium (VI) compounds, such as chromates or dichromates produces diphenylcarbazone, which ...
Chromate blood loss studies". Am. J. Med. 31 (2): 259-65. doi:10.1016/0002-9343(61)90114-0. PMID 13735596. Norfleet RG (April ...
Barium chromate - used in delay compositions, e.g. in fireworks rockets Lead chromate - used in delay compositions Potassium ... Other possibilities include permanganates, chromates, and some oxides. Generally, the less the oxidizer, the slower the burning ...
"Studies on sulphates, selenates and chromates of mercury (II)." Acta Chem. Scand 15.9 (1961): 1932-1938. Aurivillius, K. A. R. ...
... manganese with lead chromate and barium chromate (lead chromate is the principal oxidizer, barium chromate acts as burning rate ... Oxidizers: lead dioxide, iron oxides, barium chromate, lead chromate, tin(IV) oxide, bismuth(III) oxide, barium sulfate (for ... zirconium-nickel alloy with barium chromate and potassium perchlorate. boron with barium chromate [5] "PYROTECHNIC CHEMISTRY". ... modifier, the more of it the slower the reaction) [3] Tungsten Delay Composition: tungsten with barium chromate and potassium ...
This coating is passivated by chromate salts. A limitation of cadmium plating is hydrogen embrittlement of high-strength steels ...
Zinc chromate CrO3: Dark-red, odorless flakes or powder. [Note: Often used in an aqueous solution (H2CrO< ... Chromic acid (CrO3), Chromic anhydride, Chromic oxide, Chromium(VI) oxide (1:3), Chromium trioxide, Zinc chromate ...
Testing Status of Calcium chromate 10827-V. Testing Status of Calcium chromate 10827-V. CASRN: 13765-19-0. Formula: Ca.Cr-H2-O4 ...
No information is available on the use of sodium chromate Cr 51 during breastfeeding. The manufacturer recommends withholding ... Information in this record refers to the use of sodium chromate Cr 51 as a diagnostic agent. ... breastfeeding after a diagnostic dose of sodium chromate Cr 51, but does not prov … ... Sodium Chromate Cr 51 No authors listed In: Drugs and Lactation Database (LactMed®) [Internet]. Bethesda (MD): National ...
PROJECT SUMMARY Hexavalent Chromium (Cr(VI)) has been shown to cause lung cancer in humans when inhaled, with little known about the epigenetic mechanisms responsible for Cr(VI)-induced carcinogenesis. Nupr1 (nuclear protein 1) is a small, highly basic, and unfolded protein with molecular weight of 8,800 daltons, which is induced by a variety of stressors. Our preliminary data indicate that the level of Nupr1 is significantly increased in human bronchial epithelial BEAS2B cells following exposure to Cr(VI). Cr(VI)-induced activation of Nupr1 might be controlled by epigenetic regulators and AP1 transcription factors, since (i) Nupr1 transcription is increased by treating cells with inhibitors of histone deacetylases or DNA methyltransferase; (ii) Cr(VI) was found by FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements) to open chromatin domains around AP1 binding sites and ChIP-seq results (ENCODE) show the binding of AP1 factors around the promoter region of Nupr1. Our preliminary ...
Optimized PM7 data set: MERS=(1,1,1) CHARGE=0 OUTPUT THREADS=1 PM7 GRADIENTS NOTXT EF Lithium chromate (Li2CrO4) (ICSD 1972) h ... Optimized PM6_D3H4 data set: MERS=(1,1,1) CHARGE=0 EF OUTPUT THREADS=1 PM6-D3H4 GRADIENTS Lithium chromate (Li2CrO4) (ICSD 1972 ... 853 Lithium chromate (Li2CrO4) (ICSD 1972) (Previous) CrO(OH). (Back) Elements: Cr 1 O 4 Li 2 (Z = 18) (Periodic Table) (Next) ...
Bismuth chromate has been mentioned as having been used as a pigment in the early 19th century. However, it was expensive and ... Synonyms and Related Terms == basic dichromate; cromato de bismuto (Esp.); chromate de bismuth (Fr.); cromato di bismuto (It ... Composition = Bi2O3-2CrO3 ==Resources and Citations== * H. Kuhn, M.Curran, "Chrome Yellow and Other Chromate Pigments", ... NIH: [https://pubchem.ncbi.nlm.nih.gov/compound/Bismuth-chromate Information sheet] ==Physical and Chemical Properties== * ...
Effects of nickel, chromate, and arsenite on histone 3 lysine methylation Xue Zhou 1 , Qin Li, Adriana Arita, Hong Sun, Max ... Effects of nickel, chromate, and arsenite on histone 3 lysine methylation Xue Zhou et al. Toxicol Appl Pharmacol. 2009. . ... A549 cells were treated with 5 μM and 10 μM of potassium chromate Cr(VI) for 24 h(A, B and C), and 0.5 μM and 1 μM potassium ... A549 cells were exposed to 1 mM NiCl2, 5 μM chromate, and 5 μM arsenite for 24 h. After exposure, cells were co-stained with di ...
Objective Hexavalent chromate (chromate) in cement is a well-recognised cause of allergic contact dermatitis (ACD). ... Results There was a significant decline in the incidence of both ACD attributed to chromate (incidence rate ratio 0.48, 95% CI ... Conclusion The timing of this significant decline in the UK incidence of chromate attributed ACD, and the greater decline in ... Has European Union legislation to reduce exposure to chromate in cement been effective in reducing the incidence of allergic ...
Youre reviewing:DZUS® Lion Quarter-Turn Receptacle, Medium Size, Press-in, Steel Zinc Plate, Bright chromate. Nickname. ... DZUS® Lion Quarter-Turn Receptacle, Medium Size, Press-in, Steel Zinc Plate, Bright chromate ...
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Chromate reduction by whole cells of SUK 1205 was severely affected in presence of different heavy metals such as Ni(II), Zn(II ... Time course of chromate reduction by whole cells of Arthrobacter sp. SUK 1205 was determined under batch culture in V. B. broth ... Reduction of chromate increased with increase in cell density which attained maximum at 1010 cells/ml, however, reverse was the ... Chromate reduction assay with these permeabilized cells was performed in the same way as with untreated whole cells as describe ...
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Buy Potassium Chromate online at the best price. Our office is based in Mumbai, Maharashtra, India. Get contact detail in or ... Potassium chromate (K2CrO4) is a yellow chemical indicator used for identifying concentrations of chloride ions in a salt ...
Zinc chromate and red oxide are two pigments that are commonly used in metal primers. Zinc chromate provides more corrosion ... Red Oxide Zinc Chromate Primer. Capacity 360,000Ltrs/Annum Plant and Machinery cost 13.00 Lakhs ... Concerned about corrosion, zinc chromate will give better corrosion resistance. The Indian paint industry has been growing at ...
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HBM4EU chromates study: determinants of exposure to hexavalent chromium in plating, welding and other occupational settings. ... HBM4EU chromates study: determinants of exposure to hexavalent chromium in plating, welding and other occupational settings. / ... HBM4EU chromates study : determinants of exposure to hexavalent chromium in plating, welding and other occupational settings. ... T1 - HBM4EU chromates study. T2 - determinants of exposure to hexavalent chromium in plating, welding and other occupational ...
Start Over You searched for: Subjects Chromates -- poisoning ✖Remove constraint Subjects: Chromates -- poisoning ... Chromates -- poisoning. Occupational Exposure 2. The toxic action of chromic acid used as a cauterant ...
HBM4EU chromates study - Overall results and recommendations for the biomonitoring of occupational exposure to hexavalent ...
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... non-chromate, corrosion inhibitive sealant with a service temperature range from -65°F (-54°C) to 250°F (121°C). ... PR-1773 Low Adhesion Non-Chromate Corrosion Inhibitive Access Door Sealant. Description. PR-1773 Class B is a low adhesion, non ... PR-1773 Class B is a non-chromate, corrosion inhibitive, two-part, manganese dioxide cured, polysulfide compound. The uncured ... chromate, corrosion inhibitive sealant. It has a service temperature range from -65°F (-54°C) to 250°F (121°C), with ...
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice ...
Effects of Calcium Chromate in Mouse Lymphoma. Study G74975 Genetic Toxicity Evaluation of Calcium Chromate in Drosophila ... Genetic Toxicity Evaluation of Calcium Chromate in Salmonella/E.coli Mutagenicity Test or Ames Test. Study 031234 Summary Data ... Genetic Toxicity Evaluation of Calcium Chromate in Salmonella/E.coli Mutagenicity Test or Ames Test. Study 135997 Summary Data ... Genetic Toxicity Evaluation of Calcium Chromate in Salmonella/E.coli Mutagenicity Test or Ames Test. Study 369193 Summary Data ...
... and chromate (CrVI) inhibit each others uptake and translocation in As-hyperaccumulator Pteris v ... Interactive effects of chromate and arsenate on their uptake and speciation in Pteris ensiformis. Evandro B. da Silva, Yungen ... Arsenate (AsV) and chromate (CrVI) inhibit each others uptake and translocation in As-hyperaccumulator Pteris vittata. In the ...
TT-P-600 Primer Coating, Zinc Chromate (In Pressurized Dispensers) 1. By / January 4, 2022 January 4, 2022 ...
... hibitive Sealant - Pint Kit ... PPG Aerospace PR-1775 B-2 Gray PWA36760 Spec Non-Chromate Corrosion Inhibitive Sealant - Pint Kit. PPG Aerospace SealantsSKU: ... PPG Aerospace PR-1775 B-2 Gray PWA36760 Spec Non-Chromate Corrosion Inhibitive Sealant - Pint Kit ...
The fraction of chromate dissolved was them compared to the total chromate originally collected. The results of this experiment ... Results of the dissociation of chromate in primer paint particles implies the chromate dissociation may be hindered. ... This study suggests that paint particles with chromate bound in primer paint may be unavailable for bodily absorption if ... This proposed reduction make the continued use of chromate containing primer paints very difficult. There is currently no ...
  • OSHA has proposed a new strontium chromate exposure standard that would potentially cause Air Force paint facilities to be in violation of the proposed standard if adopted. (afit.edu)
  • A number of agencies have classified strontium chromate as a human carcinogen by the inhalation route, on the basis of occupational and animal studies. (cdc.gov)
  • The carcinogenicity of strontium chromate is attributed to the hexavalent chromium ion and not to strontium. (cdc.gov)
  • The International Agency for Research on Cancer (IARC) has assigned strontium chromate, along with other chromates, to Group 1, as a human carcinogen (IARC 1990, 2002a). (cdc.gov)
  • The only stable strontium compound that may cause cancer is strontium chromate, but this is due to chromium not strontium. (cdc.gov)
  • Members of the genus Arthrobacter capable of surviving in various chromium contaminated industrial areas such as tannery, chromite mining area and Department of Energy (DOE) waste sites have been explored for their chromate reducing potential by several authors [4,7-10]. (scirp.org)
  • HBM4EU chromates study - Overall results and recommendations for the biomonitoring of occupational exposure to hexavalent chromium. (bvsalud.org)
  • In the first step, the Advanced Oxidation Process (AOP) - a combination of hydrogen peroxide and ozone or ultraviolet (UV) radiation - is used to breakdown biological/organic species in biological fluids and to oxidize Iow-valent chromium to chromate. (nih.gov)
  • If chromium exists at different oxidation states, this novel method, converting chromium to chromate, gives the total chromium content in biological fluids. (nih.gov)
  • Composition = Bi2O3-2CrO3 ==Resources and Citations== * H. Kuhn, M.Curran, "Chrome Yellow and Other Chromate Pigments", ''Artists Pigments'', Volume 1, R. Feller (ed. (mfa.org)
  • Zinc chromate and red oxide are two pigments that are commonly used in metal primers. (entrepreneurindia.co)
  • Environmental organisations have welcomed a ruling by the Tribunal of the EU that overturns the authorisation granted to Dominion Colour Corporation (DCC) to supply red and yellow lead chromate pigments to European markets. (ipen.org)
  • Zinc chromate provides more corrosion resistance than red oxide, although red oxide is excellent for exposure to sunlight and exterior exposure. (entrepreneurindia.co)
  • Concerned about corrosion, zinc chromate will give better corrosion resistance. (entrepreneurindia.co)
  • Has European Union legislation to reduce exposure to chromate in cement been effective in reducing the incidence of allergic contact dermatitis attributed to chromate in the UK? (bmj.com)
  • Conclusion The timing of this significant decline in the UK incidence of chromate attributed ACD, and the greater decline in workers potentially exposed to cement strongly suggests that the EU Directive2003/53/EC was successful in reducing exposure to chromate in cement in the UK. (bmj.com)
  • Arsenate (AsV) and chromate (CrVI) inhibit each other's uptake and translocation in As-hyperaccumulator Pteris vittata . (researcher-app.com)
  • Potassium chromate (K 2 CrO 4 ) is a yellow chemical indicator used for identifying concentrations of chloride ions in a salt solution with silver nitrate (AgNO 3 ). (powderpackchem.com)
  • This proposed reduction make the continued use of chromate containing primer paints very difficult. (afit.edu)
  • There is currently no acceptable replacements for chromate containing primer paints on AF aircraft. (afit.edu)
  • IPEN and its partner organisations are continuing the fight against the use of lead chromates in paints. (ipen.org)
  • Lithium chromate and trichloroethylene. (cdc.gov)
  • Exposures to 13 micrograms/cubic meter (microg/m3) of chromates and 160ppm of toluene (108883) exceeded recommended limits in the spray painting area of the aluminum fishing boat facility. (cdc.gov)
  • PR-1773 Class B is a low adhesion, non-chromate, corrosion inhibitive sealant. (bergdahl.com)
  • Lamaka, S.: Chromate-Free Corrosion Protection Strategies for Magnesium Alloys-A Review: PART I-Pre-Treatment and Conversion Coating. (hereon.de)
  • Freshly grown whole cells of this bacterium were evaluated for chromate reduction under batch culture using Vogel Bonner (V. B.) broth as the base. (scirp.org)
  • Reduction of chromate increased with increase in cell density which attained maximum at 10 10 cells/ml, however, reverse was the phenomenon when the concentration of Cr(VI) increased gradually. (scirp.org)
  • Glycerol, glycine and glucose promoted chromate reduction efficiency of the cells when used as electron donors. (scirp.org)
  • NIH: [https://pubchem.ncbi.nlm.nih.gov/compound/Bismuth-chromate Information sheet] ==Physical and Chemical Properties== * Soluble in acids and alkalis. (mfa.org)
  • This study suggests that paint particles with chromate bound in primer paint may be unavailable for bodily absorption if inhaled and a reduced standard for painting applications may be unnecessary. (afit.edu)
  • Results of the dissociation of chromate in primer paint particles implies the chromate dissociation may be hindered. (afit.edu)
  • An overview of Genetic Toxicology Mammalian Cell Mutagenicity study conclusions related to Calcium chromate (13765-19-0). (nih.gov)
  • Results There was a significant decline in the incidence of both ACD attributed to chromate (incidence rate ratio 0.48, 95% CI 0.36 to 0.64) and ACD not-attributed chromate (0.76, 95% CI 0.69 to 0.85) between the time period preceding the EU legislation (2002-2004) and the postlegislation period (2005-2009). (bmj.com)
  • The fraction of chromate dissolved was them compared to the total chromate originally collected. (afit.edu)
  • The Bureau procedure consists of reacting chromite with molten naoh under oxidizing conditions to form sodium chromate (na2cro4). (cdc.gov)
  • Method Changes in the incidence of work-related ACD cases returned to The Health and Occupation Reporting network by dermatologists were analysed taking in to account attribution to chromate and occupation. (bmj.com)
  • High-risk notification of chromate and bichromate production workers. (cdc.gov)
  • This membrane containing a di-ammonium dicationic ligand preconcentrates chromate for its electrochemical analysis. (nih.gov)
  • En cliquant sur le bouton "Trouver le code SH associé" ci-dessus, vous pouvez trouver le code HS universel à 6 chiffres (valable pour presque tous les pays du monde) et les codes déclarables pour l'UE, le Royaume-Uni, les États-Unis, le Japon, la Chine, l'Inde et la Turquie (par ex. (findhs.codes)
  • The only stable strontium compound that may cause cancer is strontium chromate, but this is due to chromium not strontium. (cdc.gov)
  • In the first step, the Advanced Oxidation Process (AOP) - a combination of hydrogen peroxide and ozone or ultraviolet (UV) radiation - is used to breakdown biological/organic species in biological fluids and to oxidize Iow-valent chromium to chromate. (nih.gov)
  • If chromium exists at different oxidation states, this novel method, converting chromium to chromate, gives the total chromium content in biological fluids. (nih.gov)
  • Information in this record refers to the use of sodium chromate Cr 51 as a diagnostic agent. (nih.gov)
  • No information is available on the use of sodium chromate Cr 51 during breastfeeding. (nih.gov)
  • The manufacturer recommends withholding breastfeeding after a diagnostic dose of sodium chromate Cr 51, but does not provide a specific duration. (nih.gov)
  • An overview of Genetic Toxicology Micronucleus Mice study conclusions related to Sodium chromate (7775-11-3). (nih.gov)
  • The Bureau procedure consists of reacting chromite with molten naoh under oxidizing conditions to form sodium chromate (na2cro4). (cdc.gov)
  • Sodium chromate crystals were produced that contained less than 0.01 pct naoh. (cdc.gov)
  • La haute teneur en sel du pain blanc pourrait être un facteur qui contribue à la forte consommation de sodium au Maroc, surtout quand nous savons que le pain est un aliment de base dans le pays. (who.int)
  • Toutes les politiques et initiatives visant à réduire la consommation de sodium devraient cibler le pain comme outil stratégique pour réduire l'apport en sel. (who.int)
  • Exposures to 13 micrograms/cubic meter (microg/m3) of chromates and 160ppm of toluene (108883) exceeded recommended limits in the spray painting area of the aluminum fishing boat facility. (cdc.gov)