[The mechanisms of the action of radioprotectors of different chemical classes in the intestinal syndrome]

Some thiazole, triazole, thiadiazine, and heterylalkane derivatives increased the lifespan of gamma-irradiated (9-14 Gy) mice up to 6-22 days (as opposed to 4.1 days in the irradiated control). The efficacy of chemical agents within the dose range mentioned above was mainly associated with protecting intestinal epithelium stem cells the number of which was 4-9 times as large as that of nontreated animals. There was a moderate (40-50%) decrease in oxygen consumption under the effect of the most active radioprotectors.

[Radioprotective activity of aminoarylthiazoles and various mechanisms of action]

The amino group is shown to be the reaction center that is primarily responsible for the radioprotective effect of the thiazoles under study. A phenyl residue also contributes to the radioprotective effect. The influence of thiazoles on DNA biosynthesis on radiosensitive tissues plays an important role in the biochemical mechanism of their radioprotective action.

[Antisilicotic action and side effects of polypyridylethyl-methacrylate iodomethylate]

Antisilicotic and side effects of a new polymer synthetized on the basis of polymethacrylic acid were studied. The polymer not only inhibited the development of silicotic sclerosis but also induced its partial reverse development. As regards the effect intensity it appeared to be equal to highly effective polyvinylpyridine-N-oxide. The data obtained indicate the necessity of a further study of the new antisilicotic polymer with a purpose of recommending it for clinical trials.