Mutagenic activity effects

Sodium chlorite is not Hsted by the USEPA or any regulatory authority as a carcinogen. Studies conducted ia mice and rats did not show an increase in tumors in animals exposed to sodium chlorite in thek drinking water. Sodium chlorite has been found to have mutagenic activity in some in vitro test systems such as the Ames Salmonella reverse mutation assay without the presence of metaboHc activators. The significance of these test results in regard to human health is not clear because of the oxidizing effects of the chlorite ion (149). 

In summary, preliminary results from two animal models (rabbit and mouse) indicate that poly(N-palmitoylhydroxyproline ester) elicits a very mild, local tissue response that compares favorably with the responses observed for established biomaterials such as medical grade stainless steel or poly(lactic acid)/poly(glycolic acid) implants. At this point, additional assays need to be performed to evaluate possible allergic responses, as well as systemic toxic effects, carcinogenic, teratogenic, or mutagenic activity, and adaptive responses. 

Mutagenic activities across series 28 (entries 22-32) showed a distinct dependence upon the electronic effect of the substituent activity is greatest with electron donor and weakest with electron-withdrawing substituents at Z. 

Realistic prediction of the mutagenic activities of this class of mutagens requires a physicochemical evaluation of steric effects of substituents and the most widely utilised measures of such are Taft steric parameters, Es (Table 17).204,210... 

The mutagenic activity of A-acyloxy-A-alkoxyamides reflects their interaction with the primary target, which in this case is bacterial DNA. The predictive model (Equation 3) allows discovery of structural factors that either increase or diminish DNA damage. Such effects can operate either upon binding to DNA or reactivity with DNA. Both types of structural impacts have been observed. 

As pyramidal amides5,32 their Sn2 reactivity with neutral nucleophiles like /V-methylaniline parallels that of a-haloketones with amines, which, as described in an earlier section, are also strongly affected by steric effects on the a -carbon.183 SN2 reactions are in general strongly and adversely influenced by steric effects and branching / to the reactive centre and the same appears to be true for /V-acyloxy-/V-alkoxyamides 30b and 29a-e. Broadly speaking, their mutagenic activity is affected similarly. 

Steric effects, of A-acyloxy-/V-alkoxyamides mutagenic activity and, 105-106, 109-115 in nucleophilic substitution (SN2) reactions, 79-81... 

Simmon VF, Tardiff RG. 1978. The mutagenic activity of halogenated compounds found in chlorinated drinking water. In Water chlorination Environmental impact and health effects. Vol. 2. Ann Arbor, Ml Ann Arbor Science, 417-431. 

The combined synergistic effects of cyclo(Leu-Pro) and cyclo(Phe-Pro) were effective against five vancomycin-resistant enterococci (VRE) strains Enterococcus faecium (K-99-38), E. faecalis (K-99-17), E. faecalis (K-99-258), E. faecium (K-01-312), and E. faecalis (K-01-511) with MIC values of 0.25—1 mgl . It also showed activity against E. coli, Staphylococcus aureus. Micrococcus luteus, Candida albicans, and Cryptococcus neoformans with MIC values of 0.25—0.5 mg 1. This combination also showed mutagenic activity against Salmonella typhimurium TA98 and TAIOO strains in a Salmonella mutation assay. ... 

Three primary tests are incorporated in the health effects area. The microbial mutagenesis assay is based on the property of selected Salmonella typhimurium mutants to revert from a histidine requiring state to prototrophy due to exposre to various classes of mutagens. The test can detect nanogram quantities of mutagens and has been adapted to mimic some mammalian metabolic processes by the addition of a mammalian liver microsomal fraction. The test is used as a primary screen to determine the mutagenic activity of complex mixtures or component fractions. 

Results from a number of genotoxic assays show that MIBK exhibits very little, if any, mutagenic activity. Existing studies also demonstrate that MIBK is not teratogenic. In two-generation reproductive studies, rats exposed at up to 2 000 ppm 6 hours/day had some central nervous system effects and... 

In vitro studies with plasmid DNA showed that A-acyloxy-A-alkoxyamides react at G-N7 in what is most probably an Sf/2 reaction within the major groove of DNA ". However, mutagenic activity is negatively correlated with both SatI and Sf/2 reactivity trends and their mutagenic capability appears to be dependent upon their survival in cellular environment. Hydrophobic binding to DNA is the major factor governing activity, and steric effects also play a role and can influence access to the major groove or reactivity once located there" . 

Mutagenic activity. Petroleum ether extract of the aerial parts, in the ration of Drosophila at concentrations of 0.5, 1, and 5% of the diet, was active . Petroleum ether extract of the dried leaf, administered by gastric intubation to male mice at a dose of 50 mg/kg, was active h Water and methanol extracts of the seed, on agar plate at a concentration of 100 mg/mL, were inactive on Bacillus subtilis H-17 (Rec+) and Salmonella typhimurium TAIOO and TA98. Metabolic activation had no effect on the results h... 

Mutagenic activity. Ethanol (95%) extract of the dried resin, on agar plate at a concentration of 15 mg/plate, produced weak activity on streptomycin-dependent strains of Salmonella typhimurium TA98. Metabolic activation has no effect on the result " """. Resin, on agar plate at a concentration of 200 pg/plate, was active on Salmonella typhimurium TA1537 and inactive on Salmonella typhimurium TA1538 and Salmonella typhimurium TA98 " """. 

Mutagenic activity. Seed oil was inactive on Salmonella typhimurium TAIOO and TA98. Metabolic activation had no effect on the results . 

A review of the literature on experiments to assess possible chronic effects, especially mutagenic activity and carcinogenicity, of the irritant and vesicant agents reveals that these effects have not been studied systematically by current standards and techniques. 

Pitts, J. N., Jr., D. Grosjean, T. M. Mischke, V. F. Simmon, and D. Poole, Mutagenic Activity of Airborne Particulate Organic Pollutants, in Biological Effects of Environmental Pollutants (S. D. Lee and J. B. Mudd, Eds.), pp. 2f9-235, Ann Arbor Science Publishers, Ann Arbor, Ml, f979. 

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