[Measurement of proinsulin, insulin and C-peptide in human blood by high performance liquid chromatography]. / Opredelenie soderzhaniia proinsulina, insulina i C-peptida v krovi cheloveka metodom vysokoéffektivnoi zhidkostnoi khromatografii.

The technique of measuring insulin, proinsulin, and C-peptide in human blood by high-pressure liquid chromatography is described. Donors, subjects with abnormal glucose tolerance, and patients with type I diabetes were examined. The main advantage of the method over radioimmunoassay and enzyme immunoassay is the possibility of simultaneous differentiated measurement of human insulin and animal hormone administered parenterally, and separation of insulin and its precursor on the basis of difference in molecular weight and charge of molecules. The results indicate that patients with type I diabetes retain the secretion of endogenous insulin, although its level is appreciably lower than in healthy donors, and the structure of its molecules is heterogeneous, which is proven by a biphasic chromatographic peak. Inhibition of proinsulin transformation into insulin is one probable mechanism of impairment of glucose tolerance. High-pressure liquid chromatography can be used at clinical laboratories for examinations of diabetics.

[The effect of the composition of an artificial gas environment under pressure up to 5.1 MPa on the oxidation-reduction reactions in the human body]. / Vliianie sostava iskusstvennoi gazovoi sredy pod davleniem do 5.1 MPa na okislitel'no-vosstanovitel'nye reaktsii v organizme cheloveka.

In 500-m dives, lipid and carbohydrate metabolism was found to depend on the composition of hyperbaric gas mixture. Reduction of the oxygen partial pressure for over 2.0 kPa from the optimal one depressed aerobic energy-producing biochemical reactions in the human blood cells. 5 per cent of nitrogen in the hyperbaric gas mixture at 5.1 MPa suppressed the aerobic metabolism.

[Various mechanisms of regulation of lipid peroxidation in human erythrocytes after long-term exposure to hyperbaric oxygenation]. / Nekotorye mekhanizmy reguliatsii peroksidatsii lipidov v éritrotsitakh cheloveka pri dlitel'nom prebyvanii v usloviiakh giperbarii.

Intensity of lipid peroxidation and activity of antioxidant protection enzymes in erythrocytes were measured in three experiments with 10-24 days exposure of aquanauts under 4.6 and 5.1 MPa. It is established that there is no pathological intensification of lipid peroxidation when oxygen partial pressure in breathing gas mixture is optimal. This process is under reliable control by modulation of antioxidant enzymes activity. The high sensitivity of these research methods allows using them to determine exposure limitations under high pressure and optimal oxygen concentrations in breathing gas mixture.

[Effect of hyperbaric factors on the biochemical and hematological indicators in rats (in vivo) and in humans (in vitro)]. / Vliianie faktorov giperbarii na biokhimicheskie i gematologicheskie pokazateli u krys (in vivo) i cheloveka (in vitro).

The influence of hyperbaric factors on complex of biochemical and haematological parameters was examined in rats (in vivo) on donor blood samples. It was established, that the sojourn in heliox under the pressure 6.1 MPa and rO2 60 kPa results in activation of lipid peroxidation, alteration of erythrocyte oxygen transport function and the suppression of lipid metabolism. There are no significant alterations of these parameters in the comparative experiment with the pO2 40 kPa. The decompression of donor blood samples from 5.1 MPa to 0.1 MPa during 50 minutes had no significant influence on complex of biochemical, haematological and immunological parameters as compared to control probes.

[Immunologic response of divers working in the conditions of increased microbial contamination of water under pressure up to 5.1 MPa]. / Immunologichaskaia reaktivnost' akvanavtov pri rabote v usloviiakh povyshennoi mikrobno'i zagraznennosti vodno'i sredy pod davleniem do 5.1 MPa.

The complex investigation of immune and nonspecific reactivity of 30 aquanauts was carried out during five experimental saturation divings up to 350-500 m accompanied by an increase of microbic contamination in water of the hyperbaric chamber. Peculiarities of humoral immune response and phagocyte functions were found to depend on the inflammatory disease of aquanauts. It is concluded that the situational transitory immune deficiency development under the influence of hyperbaric factors is possible and changes in the microbe spectrum are real.

[Evaluation of energy metabolism and physical work capacity of divers for determining the optimal oxygen level during breathing gas mixture under pressure up to 5.1 MPa]. / Otsenka énergeticheskogo obmena i fizicheskoi rabotosposobnosti akvanavtov pri opredelenii optimal'nogo soderzhaniia kisloroda v dykhatel'noi gazovoi smesi pod davleniem do 5.1 MPa.

A complex evaluation of energy metabolism, oxygen-transport function of blood and physical work capacity of aquanauts has been performed during three imitation divings at depths of 400, 450 and 500 m in heliox as a breathing medium. These experiments have shown that optimal levels of partial oxygen pressure in artificial chamber environment are 30-33 kPa at 4.1 MPa, 32-35 kPa at 4.6 MPa and 33-34 kPa at 5.1 MPa. It is established that 24-days exposure of aquanautes to 4.6 MPa and 10-days exposure to 5.1 MPa yield no unfavourable changes of the examined organism functions. The activated lipid exchange in combination with stable carbohydrate catabolism, the elevated levels of oxygen consumption and its partial pressure in blood and transient fluctuations of erythropoiesis activity are interpreted as compensatory responses of diverse organisms under the influence of hyperbaric factors.

[State of protein and mineral metabolism following thyrocalcitonin administration during experimental osteogenesis]. / Sostoianie belkovogo i mineral'nogo obmena pri vvedenii tirokal'tsitonina v usloviiakh éksperimental'nogo osteogeneza.

Prolonged administration of thyrocalcitonine (TC) into rats (at a dose 5 un per animal) led to some alterations in protein and mineral metabolism: decrease in content of calcium and phosphorus in blood, activation of alkaline phosphatase in blood, decrease in excretion of hydroxyproline, increase in excretion of aminonitrogen with urine. Distinct correlation was observed between the metabolic activity and definite steps in reparative osteogenesis. Exogenous TC activated the cellular structures, which participated in the regenerative processes, promoted the rapid turnover of bone generation and decreased the periods of tracture healing.