[Effect of variations of the geomagnetic field and solar activity on human physiological indicators].

The influence of changes in solar and geomagnetic activity on physiological parameters of man (EEG, pulse beat, rate of sensomotor reaction and the pressure in the period of spring equinox (10.02-10.04.

[A decrease in the level of unscheduled DNA synthesis in preparations of irradiated rat hepatocyte nuclei under the effect of polyamines].

The results obtained show the possibility of polyamine (spermine and spermidine) utilization to stabilize the nuclear chromatin and to protect it against nuclease degradation in the course of isolation of liver cell nuclei. Besides, the inhibition of the unscheduled DNA synthesis induced by nuclease incision and by gamma- or UV-radiation was demonstrated in the presence of polyamines.

[Induction of unscheduled DNA synthesis in the nuclear matrix of rat hepatocytes after whole-body gamma irradiation of the animals].

DNA synthesis in hepatocytes was studied by incorporation of [3H]thymidine administered to portal vein of gamma-irradiated (80 Gy) rats. It was shown that the rate of replicative DNA synthesis decreased in hepatocytes of the regenerating liver and unscheduled DNA synthesis was induced at the nuclear matrix of resting cells of the intact liver. In addition to repair synthesis, DNA synthesis resembling replicative one ("aberrant" DNA synthesis) accounts for a considerable fraction of gamma-radiation-induced synthesis of DNA at the nuclear matrix.

[Relation of the poly(ADP-ribosylation) of proteins to the formation and repair of DNA single-strand breaks in gamma-irradiated permeable Zajdela hepatoma cells].

A study was made of the effect of poly(ADP-ribosylation) of proteins on the formation and repair of single-strand DNA breaks in gamma-irradiated (50 Gy) permeable Zajdela ascites hepatoma cells permeabilized by the treatment with 0.05% triton X-100. Incubation of gamma-irradiated permeable cells in conditions promoting DNA synthesis and providing ADP-ribosylation (in the presence of 1 mM NAD) did not cause any substantial changes in the formation of single-strand DNA breaks and did not influence their repair.