FIGURE 16-18 TA100, TA1538, and TA1535 are strains of Salmonella bearing different histidine auxotrophic mutations. The TA100 strain is highly sensitive to reversion through base-pair substitution. The TA1535 and TA1538 strains are sensitive to reversion through frameshift mutation. The test results show that S-- His+ rersion test aflatoxin B, is a potent mutation that causes base-pair substitutions but not frameshifts. [Data from J. McCann and B. N. Ames, in W. G. Flamm and M. A. Mehlman, eds. Advances in Modern Technology, vol. 5. Copyright by Hemisphere Publishing Corporation, Washington, D.C.] Ames test of aflatoxin B, mutagenicity 2000 TA100 1500 1000 OCH3 500 Aflatoxin B, TA1538 TA1535 20 40 60 80 100 120 140 Aflatoxin B, dose (ng) Revertant colonies per plate O: Aflatoxin B, forms a bulky addition product Guanine Aflatoxin B, HO HN OCH3 H2N DNA backbone mutagenicity of comp However, it became rather, some carcino mutagenic agents. Ty- enzymatic reactions FIGURE 16-16 Metabolically activated aflatoxin B, binds to DNA.

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Substance Abuse

Substance abuse refers to the use of illegal drugs in excessive quantities, as well as the misuse of legal substances such as prescription or over-the-counter pharmaceuticals or alcohol for purposes other than those intended. Drug addiction, also known as substance use disorder, is a disease that affects the brain and behavior of a person. It leads to a failure to control the use of any drug or prescription, legal or illegal.