Heavy Metals in the Environment - Chapter 3 pdf

... double-stranded (DS) DNA fractions. One of the simplest procedures in- volves an alkaline unwinding step and then DNA quantification using a fluores- cent DNA-binding stain (Hoechst 33 258) in the ... 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 adhesio...

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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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... measurement in aerosols and in biological samples (31 33 ). 2 .3. 3 Total-Reflection X-Ray Fluorescence (TXRF) Description. The principle of TXRF is the use of the total reflection of the exciting beam ... of the principal analytical methods used in environmental sciences for heavy metals determination. The monitoring of trace metals in the environment has been a s...

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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 ... Marcel Dekker, Inc. T ABLE 3 Average Daily Intake of 230 , 232 Th, 234 , 235 , 238 U, and 226 Ra by Ingestion in Food and Water and by Inhalation in the United States and China (...

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... studies, including one meta-analysis, have pointed toward the kidney and lung as target sites of lead in humans (31 35 ). There are also hints of gastrointestinal and nervous system tu- mors (33 ,34 ,36 ). ... Some evidence indi- cates that metals can replace zinc in DNA-binding zinc finger proteins (119), which are typically transcription factors that show a high site-specific DNA bind...

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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 ... is constrained in the surface water because of the prevalence of oxic conditions. On the other hand, reducing conditions offered by the aquifers lead to the mobili- zation of...

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... exist in the environment but the natural cycling of this element throughout the various envi- Copyright © 2002 Marcel Dekker, Inc. 33 . M Vahter. What are the chemical forms of arsenic in urine ... toxic levels in their drinking water, probably as a consequence of increased agricultural irrigation. In recent years the toxic potential, both carcinogenic and noncarcino- gen...

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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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... moiety chelating the Al 3 and the ammonium group remaining protonated (26). The norepinephrine-Al 3 complex inhibits enzymatic O-methylation but not N-methylation by catechol-O-methyl transferase ... as a tanning or cross-linking reagent. Al 3 seems capable of cross-linking proteins, and proteins and nucleic acids. In fluids low in citrate, transferrin, and nucleotides, the c...

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