[Biological and physico-chemical properties of Yersinia pseudotuberculosis bacterial culture having the fra-operon Yersinia pestis].

The biological and physico-chemical properties of cultures of two isogenous recombinant variants of Yersinia pseudotuberculosis were studied. The cell genomes of the cultures are distinguished from one another only by the presence or by the absence of the fra-operon, which is a determined attribute of the plague microbe capsule-forming process. The expression of the attribute is amplified by rising the microbial biomass cultivation temperature and stimulates the decrease in the viability of the bacteria and adaptation potential in vitro.

[Intensification of microbial degradation of crude oil and oil products in the presence of perfluorodecalin].

The possibility of using perfluorinated organic compounds for growing microorganisms and degrading xenobiotics has been demonstrated for the first time with perfluorodecalin (PFD), a gas-transporting component of the blood substitute Perftoran. In particular, this is promising for intensifying microbial degradation of oil and oil products and production of biodegrader biomass in synthetic mineral media. Addition of PFD to a mineral medium with crude oil and masut increased 4.

[The distribution of chromosome aberrations in cells under the action of radiation of different qualities].

The distribution of chromosome aberrations in the cultured human peripheral blood lymphocytes exposed to 6 MeV neutrons was compared with that of lymphocytes exposed to gamma-rays. The regularities of both distributions were similar.

[The cytogenetic effects of 137Cs gamma quanta].

The data on the human chromosomal level have been first obtained showing that the values of relative biological effectiveness of the 137Cs radionuclide exceed 1. These findings were allowed for during intracavitary radiotherapy in more than 50 patients with uterine body cancer.

[A polarographic method in assessing the cultural properties of the EV vaccinal strain].

The kinetic and regulatory characteristics of the oxidation metabolism of glucose, whose differences in collection cultures correspond to their capacity for growth in fluid culture medium under the conditions of aeration and the periodic addition of glucose, have been proposed on the basis of the polarographic method used for the registration of microbial breath in vaccine strain EV. Pronounced metabolic disturbances resulting from the prolonged storage of the stock culture and working standards of strain EV lead to the deterioration of their working properties.

[The cytogenetic effects of 22-MeV neutrons].

22-MeV neutrons affecting the culture of human peripheral blood lymphocytes have been studied for their cytogenetic peculiarities. Linear character of the dependence of chromosome aberrations yield within the dose range of 0.2-4.

[The modifying action of caffeine on the effect of fast neutrons in human cells].

The cytogenetic data obtained indicate a real possibility to intensify damage of the human cells as affected by rapid neurons. It can be achieved by combination of reparation inhibitors (caffeine) and rare-ionizing radiation (gamma rays) and is expressed in 5.5-fold increase of yield of chromosome damages in caffeine case and in increase of yield of exchange aberrations in the case of combination with gamma radiation.

[The state of the molecular electron carriers of the cell energy system at early periods following irradiation].

The content of non-heme iron-sulfur proteins and free radicals in the liver, cardiac muscle, and brain was studied during the period from 10 min to 7 days following X-irradiation with doses of 11.0, 7.5, and 4.

[Damage susceptibility of human lymphocyte chromosomes at different stages of the mitotic cycle in combined exposure to fast neutrons and postradiation hyperthermia].

The combined action of gamma rays (1-4 Gy) and postradiation hyperthermia on the human lymphocyte culture induces intensification of the damaging effect at the stage of DNA synthesis, i.e. at the most radioresistant stage of the mitotic cycle, the thermal intensification factor (TIF) being 1.

[Effect of sodium humate on animals irradiated with lethal doses].

A therapeutic effect of natrium humate given to experimental mongrel rats exposed to 60Co-gamma-radiation of lethal doses has been studied. A single administration of natrium humate, 5-10 min following irradiation with a dose of 193.5 mC/kg (LD100/30) leads to a 43.

[The problem of peroxidation in radiobiology].

A hypothesis is validated concerning the products of free radical oxidation of lipids and the phenol compounds as a mediator unit of the stress-syndrome. The data are reviewed on activation of peroxidation under the effect of radiation, cytochemical agents, etc., secondarily stimulating the neurohumoral system function of homeostasis regulation.

[Neutral cytoplasmatic deoxyribonuclease of the rat liver and spleen in carcinogenesis].

The activity of cytoplasmic neutral DNA in the liver and spleen of albino rats is studied when the tumour process develops after fast neutrons irradiation, when tumour is induced by 3,4-benzpyrene and after sarcoma 45 transplantation. It is shown that an increase in the enzymic activity with a further decrease during the process development is observed for all studied types of carcinogenesis in the pretumour period. Changes in the activity of natural inhibitor and the enzyme form bound with the inhibitor were not found (except for one or another index in the spleen of animals with sarcoma 45).

[Cyclic nucleotides and lipids in the realization of the radioprotective effect of ceruloplasmin].

Ceruloplasmin administered 60 min before irradiation diminished cAMP and cGMP levels, which were increased by irradiation at LD50 and LD100, and normalized cAMP/cGMP ratio in the rat liver during the first 24 h following irradiation with a dose of 6.24 Gy. The content of phospholipids increased and that of cholesterol decreased under the effect of ceruloplasmin leading to normalization of the molar cholesterol/phospholipid ratio in the rat liver on the 7th day of radiation sickness (LD50, 6.

[Susceptibility to damage of human lymphocyte chromosomes in different stages of the mitotic cycle when exposed to fast neutrons with an average energy of 6 MeV].

Cytogenetic susceptibility of human lymphocytes in the culture to lesion is studied under the effect of neutrons with 6 MeV energy at different stages of the mitotic cycle. Radiosensitivity of human lymphocytes under the influence of gamma-quanta and neutrons is found to vary identically during the whole cycle. These variations are less expressed in the case of neutron irradiation.

[Effect of fast neutrons on the process of muscle cell differentiation].

A study was made of the effect of fast neutron on differentiation of myoblasts in vitro. The results obtained indicate that irradiation inhibits the differentiation of myoblasts in culture. Irradiation with fast neutrons (1.

[Circadian and seasonal rhythms in the radiosensitivity of mongrel white rats].

From experiments in albino mongrel rats it is shown that the radiosensitivity of gamma-irradiated (60Co) animals follows a daily rhythm. A synchronization of the daily rhythms in radiosensitivity was noted in winter and during the first spring month which was impaired in April. Established were the rhythms of radiosensitivity for three seasons, i.

[Participation of cyclic nucleotides in realizing the effect of ceruloplasmin during irradiation].

It was shown that a single intraperitoneal administration of human ceruloplasmin 60 min before irradiation (4.22, 5.28 and 7.

[Role of ceruloplasmin in the resistance of the organism to x-irradiation].

It was shown that a single administration of homogeneous and heterogeneous ceruloplasmin in different doses 1 h before or after irradiation ( LD40 and LD100) increased the survival rate of rats. Ceruloplasmin improved some indices of peripheral blood and bone marrow at early stages of radiation affection. A higher ceruloplasmin activity was observed in blood serum of irradiated animals.

[Neutral DNAse activity in rat tissues in radiation carcinogenesis].

The activity of neutral DNAse and its natural protein inhibitor was determined in the liver, brain and spleen of albino rats with malignant tumours of mammary gland and other organs. The tumours appeared 14-20 months after the irradiation of rats with fast neutrons (0.5-1.

[Dosimetric and radiobiological characteristics of the radiation field from the reaction d(50 MeV)--Be].

The rate of the total absorbed dose within a radiation field produced by the reaction of accelerated (up to 50 MeV) deuterons with a thick beryllium target has been determined and the uniformity of the dose field studied. LD50/30 for C57Bl mice has been evaluated in a mixed gamma/neutron field.

[Effect of thyroxine on the number of cells with aberrant chromosomes in the liver of rats following x-ray and neutron irradiation].

T4 effect on the quantity of cells with chromosome aberrations in rat liver under the hormone administration after X-ray irradiation was compared with that after neutron irradiation. It is shown that T4 administered after neutron irradiation does not decrease chromosome injury, which is considered as a proof of its indirect effect after X-ray irradiation by means of genetic structure reparation.