Effect of Chemically Transformed Macrocyclic Polyene Antibiotics on Tumor Cells.

Comparative analysis of the effects of chemically transformed polyene antibiotics pimaricin, nystatin, lucensomycin, amphotericin B, and levorin on biological objects in vivo and in vitro revealed the greatest biological activity of original amphotericin B and levorin with its derivatives. The study also examined the effects of alkyl derivatives of amphotericin B and levorin modified in certain parts of the lactone ring on the lipid and biological membranes. It is established that methylated levorin possesses larger biological activity than the original antibiotic. Examination of the effects of alkyl derivatives of levorin and amphotericin B on cell cultures C6 (rat glioma) and HeLa (human cervical carcinoma) in vitro revealed the antitumor action of methylated levorin and original amphotericin B.

[Effect of electromagnetic radiation of millimetric wave band on genome of somatic cells]. / Vozdestvie élektromagnitnykh izlucheni millimetrovogo diapazona na genom somaticheskikh kletok.

The paper presents the characteristic of molecular-genetic processes occurring in populations of cells bone marrow, blood, thymus and spleen of animals exposed to electromagnetic radiation of millimetric wave band. Disturbances in the processes of cell cycle, DNA replication and repair, changes in the frequency of cells with micronuclei and cell death by apoptosis mechanism were shown to depend on the degree of differentiation and mitotic activity of cells.

[Effect of external gamma-irradiation on the genetic apparatus of somatic cells of rat fetus]. / Deistvie vneshnego gamma-oblucheniia na geneticheskii apparat somaticheskikh kletok zarodyshei krys.

Cytogenetic effects of different radiation dose rate and dose value were studied in fibroblasts of 20-day old rat fetuses and new-born ratlings. Quantitative and qualitative changes in the occurrence frequency in the spectrum of chromosome aberration types were revealed and changes in aneuploid fibroblast ratio were observed. The damages in the fibroblast chromosome structure of fetuses remain after birth (2-day-old ratling) and they were also observed in fetuses of the second generation.

[The effect of acute external gamma-irradiation and thyroid glands dysfunction on rat reproductive system and frequency of structural mutations in somatic cells of pregnant females and their offspring]. / Vliianie ostrogo vneshnego vozdeistviia gamma-izlucheniia i narusheniia funktsii shchitovidnoi zhelezy na reproduktivnuiu sistemukrys i chastotu strukturnykh mutatsii v somaticheskikh kletkakhberemennykh samok i ikh potomstva.

Experimental hypofunction of thyroid gland, caused by mercazolil administration, and acute external exposure to 0.5 and 1.0 Gy of gamma-irradiation were shown to result in disturbance of reproductive function in puberal females and of estrogenreceptor interaction, in reduction of pregnancy probability, increase in pre- and postimplantation lethality of fetuses as well as in rise in the frequency of structural mutations in somatic cells of pregnant rats and their offspring.