Toxic effects of metals

Arsenic competes with phosphate for incorporation into precursors of DNA or RNA such as dATP, rATP, dGTP, rGTP, etc. (28,37.38.39). If arsenic is incorporated into molecules such as ATP, then it may also be added to serine and threonine residues of cellular proteins, since protein kinase uses the terminal phosphate of ATP in the phosphorylation of a variety of cellular proteins. 

ACS Symposium Series American Chemical Society Washington, DC, 1980. 

Transformation of Cells in Tissue Culture by Carcinogenic Metals and Their Compound  

Mammalian cell cultures have been used as the basis of several systemsin detect ng the potential carcinogenic activity of chemicals. Basically, two general approaches have been utilized continuous cell lines and primary cell cultures. Cell lines have the advantage of ease of use, in that cultures do not have to be obtained fresh from animals prior to each test, but may be maintained for months to years by proper subculturing techniques. They have the disadvantage of possessing one or more transformed characteristics (e.g., immortality). In some cases cell lines may also lack certain enzyme systems required for metabolic activation of chemicals. Some of the cell lines used for transformation assays include the murine (BALB/3T3) A31 system ( ), and the baby kidney-21 (BHK-21) systems (43). 

Primary cell cultures have advantages over cell lines in that the cells are not initially immortal, and usually have none of the transformed characteristics which may be seen in some cell lines Additionally, the embryonic cells which are most 

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Coyer, R.A. (1996). Toxic effects of metals. In Casarett and DoulTs Toxicology The Baste Science of Poisons (C. D. Klaassen, Ed.), pp. 691-736. McGiaw -Hill, New York,... 

GoyerRA. 1986. Toxic effect of metals. In Klaassen CD, et al. ed. Casarett and Doull s Toxicology The basic science of poisons. 3rd ed. New York, NY Macmillan Publishing Co, 582-588, 598-605. 

Mn2+ active transport system in Staphylococcus aureus. These metal-microbe interactions result in decrease microbial growth, abnormal morphological changes, and inhibition of biochemical processes in individual (Akmal et al. 2005a,b). The toxic effects of metals can be seen on a community level as well. In response to metal toxicity, overall community numbers and diversity decrease. Soil is a living system where all biochemical activities proceed through enzymatic processes. Heavy metals have also adverse effects on enzyme activities (Fig. 1). 

Goyer, R.A. 1986. Toxic effects of metals. Pages 582-635 in C.D. Klaassen, M.O. Amdur, and J. Doull (eds.). Casarett and Doull s Toxicology, third edition. Macmillan, NY. 

Malaney GW, Sheets WD, Quillin R. 1959. Toxic effects of metallic ions on sewage microorganisms. Sewage Ind Wastes 31 1909-1915. 

Goyer RA Toxic effects of metals. In Klaasen CD et al. (eds) Casarett and DoulPs Toxicology. The Basic Science of Poisons, 3rd ed, pp 605-609. New York, Macmillan Publishing, 1986... 

Selenium is readily available in a variety of foods including shrimp, meat, dairy products, and grains, with a recommended daily intake of 55 to 70 jug. It occurs in several forms with Se+6 being biologically most important. Selenium is readily absorbed by the intestine and is widely distributed throughout the tissues of the body, with the highest levels in the liver and kidney. It is active in a variety of cellular functions and interacts with vitamin E. Selenium appears to reduce the toxic effects of metals such as cadmium and mercury and to have anticarcinogenic activity. Selenium produces notable adverse effects both in deficiency and excess thus recommended daily intake for adults is approximately 70 Jg/day but should not exceed 200 pg/day. 

Goyer RA, Clarkson TW. Toxic effects of metals. In Klaassen CD, ed. Cassarett and DouII s Toxicology, The Basic Science of Toxicology. 6th ed. New York McGraw Hill, 2001. 

Goyer, Robert A., and Clarkson, Thomas W. (1996). Toxic Effects of Metals. In Caserett and Doull s Toxicology The Basic Science of Poisons, 5th edition, ed. Curtis D. Klaasen. New York McGraw-Hill. 

It is for these reasons that much of the experimental work on metal tolerance has relied on laboratory tests for tolerance that seek to isolate the toxic effects of the metal from other possible factors. The most widely used technique is the root elongation test, in which the toxic effects of metals on roots are used to assess tolerance. Cuttings or tillers (for grasses) are grown in solutions containing varying concentrations of the... 

R.A. Goyer, Toxic effects of metals, Chapter 19, In, Casarett and Doull s Toxicology The Basic Science of Poisons, 4th ed., Amdur, M.O., Doull, J., and Klaassen, C.D., eds., Pergamon Press, New York, 1991. 

Goyer, R. A. 1991. Toxic effects of metals. In Casarett and DouU s toxicology. The basic science of poisons, 4th ed., ed. Amdur, M. O., Dull, J., and Klassen, C. D. New York Pergamon Press. 

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