Heavy Metals in the Environment - Chapter 19 (end) pptx

... be determined in a simple enzyme assay using the chromogenic substrate o-nitrophenol-β-d-galactose (46). This is of some use in the laboratory, but of little use in making a biosensor. The lux genes ... exploit these biological mechanisms to determine the amount of ‘‘bio- available’’ heavy metal in natural and industrial environments. These methods are still in their infan...

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... trapped in the intestinal mucosa, not reaching the systemic circula- tion to the same extent as in persons with normal zinc intake and therefore in- creasing susceptibility to copper deficiency. The ... analy- sis of the current state of knowledge of heavy metals in the environment. The volume begins with a chapter on the essentiality and toxicity of metals. Th...

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... ions. These two oxidation states are the most common in environmental samples. The redox method using the Fe(II)/Fe(III) system in the presence of 1,10-phenanthroline and diphosphate in a flow-injection ... of the principal analytical methods used in environmental sciences for heavy metals determination. The monitoring of trace metals in the environment has been...

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... vivo. 4.4 Protein-Protein Interactions Heavy metals have been shown to in uence protein-protein interactions. One example is the disruption of the E-cadherin/catenin cell adhesion complex via the displacement ... and intracellular stability of newly synthesized proteins. An interesting new finding is the linkage between heavy metal–induced toxicity and the function of the ub...

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... cis-diaminodichloro-platinum and other platinum complexes have become first-line drugs in the treatment of certain types of can- cer. Studies with radioactive cis-diaminodichloro-platinum indicate ... 94 PBq in 196 3 in the Northern Hemisphere, and of 15 PBq in 196 5 in the Southern Hemisphere. A transient, Chernobyl-related peak of ϳ2 PBq 90 Sr was observed in 198 6. A su...

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... to indirect DNA damage, several metals can cause the genera- tion of DNA-damaging radicals. These, in turn, can cause various DNA lesions, including single- and double-strand breaks and DNA-protein ... Publications, 199 0. 7. International Agency for Research on Cancer Monographs on the Evaluation of the Carcinogenic Risks to Humans. Vol 52. Chlorinated Drinking-Water; Chlorina- ti...

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... optimizing conditions for the remediation of As- contaminated soils using fungi. In addition, there is little information in the litera- ture on the nature of fungi present in As-contaminated ... scorodite in the mine wastes, generated during centuries of silver, zinc, and lead mining (126,127), leach As into the aquifers and cause natural As contamination in the drinkin...

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... mg/kg, the former diet pro- viding a calculated daily intake of approximately 19 µg/ (plus 31 µg from yams). This intake would be the equivalent of ingesting 1 L of drinking water containing arsenic ... largest contributor to arsenic release in the environment is the mining and smelting of nonferrous metals. The burning of fossil fuels follows next in signi - cance. The...

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... 2. Metallothionein is a family of proteins with molecular weight of approxi- mately 6500 Da, rich in cysteine, and with seven metals distributed in two do- mains, the - and β-clusters. The dominating metals ... after inhalation of fumes containing Cd. Skin contact or Cd exposure via the skin is not known to cause health effects in humans or animals. Metallothionein-4 is pre...

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... buthionine sulfoximine was associated with decreases in the level of single-strand breaks. Interestingly, the number of DNA-protein cross-links and interstrand cross-links was only margin- ally ... a decrease in poly- merase arrest and cross-links but not in total Cr binding, further substantiating the idea that DNA cross-links are the polymerase-arresting lesion. These observa-...

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