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One of actions of medical protection of staff is carrying out of indication of poisoning and high-toxic substances. It is shown, that indication toxic substances is carried out with use of means of the continuous and periodic control: display elements, automatic gas alarms and gas detector, the army device of chemical investigation, the device of chemical investigation of medical and veterinary services, the medical device of chemical investigation, medical field chemical laboratory, etc. Opportunities of the devices intended for equipment of divisions and establishments of medical service Armed Forces of the Russian Federation with the purpose of carrying out of indication of chemical substances are analysed. Offers on perfection of the organization and carrying out of indication of chemical substances in medical divisions and establishments Armed Forces of the Russian Federation are formulated, prospects of their equipment are proved by modem indicator devices and the equipment.

Prophylaxis of chemical poisoning in the Army and Navy assumes carrying out of a complex of measures, directed on saving of life, health and military professional serviceability of staff in conditions of action of factors of chemical character in peaceful and war time. It requires from the medical staff effectuating special sanitary and preventive measures, including realization of the effective medical control over working conditions of soldiers and civilian personnel on objects, where toxic chemical substances are used, propagation of medical and hygienic knowledge, regular increase of knowledge level and practical skills of military doctors.

Accumulation and excretion of beta-carotene in rat liver tissue were studied when the carotinoid was intraperitoneally administered as olive oil as suspension and a water liposomal suspension. Single injection of the liposomal form of beta-carotene caused an increase in its content in liver tissue. If beta-carotene was administered at a dose of 10 mg/kg its maximal content 44 mg/g of the tissue was observed within one day, and at a dose of 50 mg/kg, its maximal content constituted 178 mg/g within two days. Administration of beta-carotene as an oil suspension at a dose of 50 mg/kg led to a considerably slight accumulation in rat liver tissue with the maximal value of 12 mg/kg of the tissue within two days. Possible use of beta-carotene various forms, as well as experimental models for study their biological activity are discussed.

A study was made of the effect of relatively low gamma-radiation doses (up to 10 Gy) on the ability of Ehrlich ascites tumor cells to induce peroxidation in lipids of liposomes from egg lecithin. The mechanism of this peroxidation is probably associated with the release from cells of catalyzers which perform free-radical oxidation of higher unsaturated fatty acids. Two processes occur upon irradiation of cells: disintegration of the released catalyzers, and stimulation of their release from cells. Correspondingly, the formation of malonic dialdehyde was inhibited or stimulated depending on the radiation dose and time of the combined incubation of liposomes and cells. On the basis of the data obtained a conclusion is made that the modification of the effect of malonic dialdehyde formation upon oxidation of liposomes by the exposed cells is conditioned by the effect of radiation on cell membranes.

In the presence of intact Ehrlich ascite carcinoma cells and the supernatant obtained by preincubation and subsequent precipitation of cells, egg phosphatidylcholine is oxidized in liposomes to form malonic dialdehyde (MDA). Catalase and carbon dioxide markedly reduce, whereas sodium azide increases MDA accumulation during liposome incubation with the cells. EDTA, diethylthiocarbonate and alpha-tocopherol effectively inhibit, whereas ascorbate and cysteine strongly activate MDA synthesis in both cases. Superoxide dismutase has no appreciable effect on these processes. It is concluded that metal-containing catalysts and the H2O2 released by intact cells into the incubation medium induce lipid peroxidation in liposomes.

EFfect of linoleic acid hydroperoxide (I) and Fe++ on viscous elastic properties of cell membranes of Ehrlich ascite carcinoma was studied by the method of K+-dependent swelling. It has been shown that the action of 1 and Fe++ is of similar character, and the effect depends on the incubation time and concentration of agents in the incubation mineral solutions. After 2 h incubation the concentration relationships have two patterns characterized by increased swelling at concentrations 10(-6)-10(-5) M and inhibition of this process at concentrations above 10(-5) M. After 4 incubation only the inhibition effect of observed, which seems to reflect the increase of cell membranes rigidity conditioned by the formation of "joints" resulting from the interaction between the products of lipid peroxide oxidation and membrane macromolecules.

The onset of 3H-thymidine incorporation in DNA precedes a short-term activation of cell respiration. gamma-Irradiation (5 Gy, 0.1 Gy/s) significantly inhibits oxygen consumption by human peripheral blood lymphocytes. It should be noted that time dependence maxima of oxygen consumption are shifted towards later times of cultivation.

Lipid peroxidation activated by low concentrations of Fe2+ ions in a medium (1-5 microM) and gamma-quanta (10-50 Gy) stimulates the oxygen consumption and oxidative phosphorylation during the initial period of incubation (10-20 min). With relatively high concentrations of Fe2+ ions and higher radiation doses (50-100 Gy) inhibition of the activity of mitochondria is registered with respect to both indices.

The effect of lipid peroxidation (LPO) induced by Fe2+ and linoleic acid hydroperoxides in intact cells on the rate of DNA synthesis was investigated. It was found that intensification of LPO is accompanied by a decrease of DNA synthesis rate. Under effects of linoleic acid hydroperoxides, the repression of DNA synthesis is enhanced.

Linoleic acid hydroperoxides delivered to Ehrlich ascites tumor cells in vitro in a concentration reaching a threshold one (approximately 10(-5) M) sharply decrease their ionic permeability and the value of membrane capacity. With suprathreshold hydroperoxide concentrations (greater than 10(-5) M), the specific yield of chromosome aberrations and the share of aberrant cells increase while the mitotic index decreases. The correlation between general regularities and the equality of the threshold concentrations, with a reference to membrane and genetic effects of hydroperoxides, is thought to be an indication of a close relationship between membrane lesions caused by the development of induced lipid peroxidation and injury to genetic apparatus of the cell.

A relationship between lipid peroxide oxidation (LPO) in biomembranes and kinetics of oxygen uptake by intact cells and cells under hypotonic shock in the course of their incubation has been studied. Different effect of bivalent ferrum ions--activators of LPO was found; it depended on cell integrity. In the cells under normal physiological conditions the rate of oxygen uptake was independent of the amount of LPO products, while in the cells placed into hypotonic medium it decreased on the background of LPO intensification as compared to the normal one. Peculiar effects of the LPO products on intact cells seem to be related to spatial disconnection of respiratory centres and to localization of peroxide oxidation reactions.

SH-Containing radioprotective agents, for instance, cysteine, cystamine, dithiothreitol, exert an antioxidant effect on gamma-radiation-induced lipid peroxidation in mitochondrial membranes and, concurrently, uncouple oxidation from phosphorylation. A radiosensitizer, N-ethylmaleimide, on the contrary, being a pro-oxidant of lipid peroxidation couples oxidation and phosphorylation. At the same time, changes in the lipid peroxidation system and in the energy production processes, observed after irradiation of a mitochondrion suspension containing modifiers, are accompanied by the increased destruction of mitochondrial membranes as compared to irradiated controls.

UV-irradiation of mitochondrial membranes causes formation and accumulation of fluorescing products in the course of incubation, like it takes place during the initiation of peroxide oxidation by the iron--ascorbate system. The rate of the change of mitochondria fluorescence and the level of TBA-products in them do not correlate, which points to the difference in the formation mechanisms of these products in the course of incubation. However, a correlation is observed between the initial fluorescence intensity and the number of TBA-active products in mitochondria, which increases with the increase of the time of UV-irradiation.

It is shown that incubation of EAT cells in the presence of Fe2+ ions caused the threshold decrease of active and capacitance constituents of cell suspension impedance and rate of ion efflux from cells to the isotonic sucrose media, and decrease extent rose with an increase of Fe2+ ion concentration and temperature. A discrepancy between the results described and experimental model system data is discussed.

In experiments on Ehrlich ascites tumor cells it was shown that lipid peroxidation induced by gamma-rays and Fe2+ ions was accompanied by a decrease in the endogenous SH-group content at early times after exposure (during 3-hour incubation). It was also established that no significant changes occurred in the oxygen uptake by Ehrlich ascites tumor cells depending on radiation dose of Fe2+ ion concentration. If cells were pre-kept under hypotonic conditions an additional decrease in cell respiration and SH-group content and activation of lipid peroxidation was noted.

No activation of lipid peroxidation and structural rearrangements were noted in the lipid phase of synaptosome membranes after exposure of animals to electrons of 300 Gy/min at doses inducing cerebral lesions. At the same time, in isolated synaptosome membranes, radiation induced defined changes manifested by a decrease in tryptophan fluorescence.

The rate of fluorescent product formation during the peroxidation of polyunsaturated linolenic acid or egg phosphatidylethanolamine and also during the oxidation of linolenic acid together with a phenylalanine and synthetic phosphatidylethanolamine 1,5--3 times more intensive after previous UV-irradiation of the unsaturated fatty acid. Schiff bases are fluorescent products in amine containing systems which are produced in the reaction of the malonaldehyde with amines. It is possible that fluorochromes produced during the only unsaturated acid oxidation are the result of the radical recombination. Accumulation of the oxidated products determined by TBA-reactive substances does not inevitably correlate with the fluorescent intensity in explored systems.

Light scattering (90 degrees) of Ehrlich ascites tumor and sarcoma 37 cell suspension in the temperature range 25-60 degrees C was studied (heating velocity was 3 grad/min). It is found that the scattering curve has the peak at 46 degrees C and two plots which are typical of phase transitions in the membranes; the first plot in the range 40-46 degrees C is reversible and the second one at 46-51 degrees C is irreversible. It is proposed that 46 degrees is a critical temperature for the membranes structure stability and viability of the studied cells.