PubMed Health⌕ Search

Biomedical subjects

R Cihák

Publications and source records attributed to R Cihák.

At least 37 records · Page 2Linked to original sources

Benzidine and 3,3'-dichlorobenzidine (DCB) induce micronuclei in the bone marrow and the fetal liver of mice after gavage.

Single oral dose of benzidine (300 mg/kg) and DCB (1000 mg/kg) to male ICR mice elicited positive response in the bone marrow micronucleus test. In the transplacental micronucleus test, the compounds were administered to pregnant females in the same manner. A significant increase in the frequency of micronuclei occurred in the fetal liver, but not in the bone marrow of mothers. The relative values of bone marrow and transplacental micronucleus tests for the prediction of carcinogenicity of these compounds is discussed.

3,3'-Dichlorobenzidine↗

Cytogenetic effects of quinoxaline-1,4-dioxide-type growth-promoting agents. III. Transplacental micronucleus test in mice.

The growth-promoting agents carbadox and olaquindox were active in the mouse transplacental micronucleus test, whereas cyadox was ineffective. Chemicals were administered p.o. and i.p. at a dose of 100 mg/kg and the effect was observed 18 h after treatment. The effects observed in fetal liver were parallel to those in maternal bone marrow, but fetal tissue was approximately 2-3 times more sensitive.

Administration, Oral↗

Cytogenetic effects of quinoxaline-1,4-dioxide-type growth-promoting agents. I. Micronucleus test in rats.

The cytogenetic activities of 3 growth-promoting agents carbadox, olaquindox and cyadox were examined by the micronucleus test. These chemicals were administered i.p. to male Wistar rats 30 and 6 h before they were killed. Single-dose levels were 5, 10, 15, 30, 60, 90, 120 and 240 mg/kg for carbadox; 30, 60, 90, 120 and 240 mg/kg for olaquindox; and for cyadox 30, 60, 120 and 240 mg/kg. Over the entire dose range tested, carbadox induced a statistically significant increase in the number of micronucleated polychromatic erythrocytes in the rat bone marrow, whereas similar activity of olaquindox started at a dose of 2 X 60 mg/kg. The effect of cyadox was very low even at the highest dosage tested. Further testing of the genotoxicity of this class of chemicals is required. The genetic activity of the solvent used (dimethyl sulfoxide) is briefly discussed.

Animals↗