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Biomedical subjects

S M Ivanova

Publications and source records attributed to S M Ivanova.

At least 55 records · Page 3Linked to original sources
PubMedDate not supplied

[The red blood system in men during long-term head-down bed rest].

Red blood was analyzed in six 25 to 40 yr. old male volunteers in a 120-d head-down bedrest (HDBR) study. The hematological investigation included morphological analyses (erythrocyte count and hemoglobin), and determination of iron turnover, erythrocyte IgA, IgG and IgM, metabolism, lipids and phospholipids, and lipid peroxidation rate (LPO). At the beginning of HDBR (day 7), the erythrocyte count and hemoglobin content were found increased w/o any visible changes in the other parameters. Further exposure to HDBR (days 50-100) resulted in modification of intracellular metabolism in erythrocytes, increases in serum iron, and serum and erythrocyte ferritin. On HDBR days 50 and 100, and post-HDBR day 9, cholesterol was increased, LPO intensified and antioxidant activities inhibited, which suggested destabilization of the cell membrane. Hematological shifts in the bedrested volunteers were of the type and pattern similar to those in cosmonauts who fulfilled extended space missions.

Adult↗
PubMedDate not supplied

[Investigation into fractionating of hydrogen and oxygen stable isotopes aboard the international space station].

Results of isotope investigations of atmospheric condensate and potable water supplied from Earth confirmed the fractionating of hydrogen and oxygen stable isotopes in the organism of ISS crewmembers. Samples of ISS atmospheric condensate were characterized by altered concentrations of 18O2 and deuterium. Atmospheric deuterium quantities varied in the interval of -67 to 79 +/- 3 ppm, whereas water deuterium made up -85 +/- 3 ppm as compared with SMOW. Atmospheric condensate consists of water vapor transpired and perspired by humans. In addition, cells of crews' red blood were also found to contain increased concentrations of deuterium as compared with the deuterium content of potable water. Results of isotopes measurements in urine, blood, saliva and potable water in a chamber experiment also evidenced in favour of the body fractionating of the stable isotopes of hydrogen and oxygen.

Chemical Fractionation↗
PubMedDate not supplied

[Comparative study of the activity of immunoglobulin G and therapeutic preparations of normal human immunoglobulin in patients with systemic lupus erythematosus and rheumatoid arthritis and in healthy persons].

The authors consider that the development of immunopathological reactions in SLE, AIDS depends on the reduction in normal gamma-globulin level in the patient's serum. The sera with anti-DNA, anti-HIV antibodies show a decreased binding of corresponding antigens and decreased concentrations of gamma-globulin with normal features.

Adolescent↗
PubMedDate not supplied

[Morphobiochemical assay of the red blood system in members of the prime crews of the International Space Station].

According to the experiment Hematology protocol, blood samples from the Russian members of ISS prime crews 1 to 5 were gathered on L-30 and R+0, 7, 15 to study metabolic parameters (ATP, reduced glutathione, LHG and glucose-6-phosphate dehydrogenase activities). Lipid spectrum of membrane erythrocytes was determined in frozen erythrocyte mass; iron turnover and erythropoietin were investigated in frozen serum. Ratios of different erythrocyte forms were established in 32 microl of fixated whole blood using scanning electron microscopy. On R+0, the morpho-biochemical parameters of red blood appear to still carry the imprints of space effects and, to an extent, certain difference in the setting of blood sampling from the Mir crew on landing in the space "shuttle" vehicle. Low level of iron and significantly increased erythropoietin on R+0 are the testimony of intensive hemoglobin production and an adequate bone morrow response to the increased oxygen demand. Shifts in erythron are of no clinical implications but indicative of the red blood adaptation to the factors of space fight.

Adaptation, Physiological↗
PubMedDate not supplied

[Cytogenetic and biochemical assay of an unidirectional effect of chronic combined exposure of laboratory animals to isoeffective concentrations of chemical substances].

Chronic combined exposure to low concentrations of chemical substances (equal to the maximal admissible limits for space vehicles) is fraught with an increase in chromosomal aberrations in bone marrow cells as compared with the spontaneous chromosome aberration rate. In addition to the cytogenetic evidence, there were also statistical phase shifts in metabolic parameters of erythrocytes (enzymes involved in the basal metabolism and a number of metabolites), leukocyte count in peripheral blood, and the total quantity of karyocytes in the bone marrow. No significant changes were found in organs of the immune and reproductive systems.

Acetone↗
PubMedDate not supplied

[Anti-cardiolipin antibodies and other immunological disorders in patients with systemic scleroderma].

A total of 104 patients with scleroderma were examined. Anticardiolipin antibodies were detected in 37.5 per cent of the patients with systemic scleroderma and in 3 per cent of healthy individuals; they were more often detected in 46.8 per cent of the patients with diffuse affections of the skin, atherosclerosis, Raynaud's syndrome accompanied by ulcero-necrotic affections of the skin as compared to patients with restricted affections of the skin (sclerodactylia and focal scleroderma)--29.8 per cent. No significant changes in the frequency of detecting a rheumatic factor, antibodies to Scl-70 were revealed in subgroups of patients with scleroderma, positive and negative anticardiolipin antibodies. Of the greatest interest is a significant difference in levels of C-reactive protein which were high in half of the patients with anticardiolipin antibodies. Anticentromere antibodies were detected twice as more often in patients without anticardiolipin antibodies that corresponded to systemic sclerodermia with minimum involvement of the skin into the pathological process. It is suggested that ulcero-necrotic affection of the skin in systemic sclerodermia is associated with C-reactive protein but it is not of an immunocomplex nature.

Autoantibodies↗
PubMedDate not supplied

[Effect of long-term space flight on erythrocyte metabolism and the function of the erythrocyte membrane].

This paper presents the data about red blood cell metabolism and the structure and function of erythrocyte membranes obtained from two cosmonauts after their 326- and 160-day flights. In both cases we observed inhibition of energy formation (decrease of the rate of glycolysis and ATP content) and enhancement of oxidative processes (decrease of reduced glutathione and activity of antioxidative enzymes). The above changes in the metabolic status of erythrocytes are correlated with shifts at the membrane level, particularly with variations of membrane lipids, phospholipid spectrum and ratios of phospholipid fractions, alteration of membrane-bound enzymes (ATPase) and increase of cell resistance to acid hemolysis. The changes in the erythrocyte membrane leading to lower cell deformability and possible shifts of blood rheological properties give evidence that it is necessary to use preventive membrane stabilization measures at certain flight stages and during readaptation.

Adenosine Triphosphatases↗
PubMedDate not supplied

[Lipid peroxidation in the human blood during a 120-day period of anti-orthostatic hypokinesia].

Time-course variations in the accumulation of endogenous products of lipid peroxidation and the state of antioxidative enzymes--superoxide dismutase and catalase--in blood of men exposed to antiorthostatic hypokinesia (-4.5 degrees) for 120 days were investigated. It was found that bed rest led to stimulation of lipid peroxidation which was measured as increased concentrations of lipid hydroperoxides and final products of lipid peroxidation in blood. Vitamin E and drugs with a specific metabolic action produced a normalizing effect on the content of products of lipid oxidative destruction. Special exercise regimens had a similar but less significant effect.

Adult↗
PubMedDate not supplied

[Lipid peroxidation in tissues of rats exposed to head-down tilt, exercise or immobilization stress].

Lipid peroxidation in tissues of rats exposed to antiorthostatic hypokinesia (-15 degrees) for 60 days, heavy-load exercise (swimming) and 2-hour immobilization was investigated polarographically. Antiorthostatic hypokinesia produced activation of free-radical lipid peroxidation in skeletal muscles, myocardium and plasma which reached a peak on hypokinesia day 3 and remained elevated by day 60. Exercise and immobilization applied during hypokinesia led to an accumulation of endogenous lipid peroxidation products in skeletal muscles and in the heart, although in a lesser degree. It is postulated that during hypokinesia lipid peroxidation is most probably activated due to the following factors: increased activity of the hormonal component of the sympathicoadrenal system, accumulation of excessive quantities of free fatty acids, and reduced activity of anti-oxidant enzymes.

Animals↗
PubMedDate not supplied

[Effect of intensive operator activity on lipid peroxidation processes in the human body].

It has been demonstrated that the stress associated with an active mental work for 2 hours leads to a high rate of lipid peroxidation which results in a greater amount of products of lipid peroxidation in blood and pentane in exhaled air. Simultaneous measurements of blood catecholamines have shown their significant increase immediately after exposure to the stress effect. It can therefore be concluded that a stress situation enhances lipid peroxidation in the human body.

Breath Tests↗
PubMedDate not supplied

[Characteristics of metabolism of human erythrocytes after long-term space flight].

Before and after the 150-day Salyut-7 flight the crewmembers were examined for their red blood metabolism, viz: major metabolic pathways (glycolytic and pentosophosphate), erythrocyte resistance, membrane permeability and lipid peroxidation rate. The resulting data indicate that the metabolic and membrane changes were not pathological and can be classified as adaptive.

Adenosine Triphosphate↗
PubMedDate not supplied

[Metabolic disorders in men kept in an environment with a low ammonia content and their correction by physical exercise].

In two series of prolonged studies metabolic changes of men kept in an environment with an ammonia concentration of 2 and 5 mg/m3 were investigated. In this chronic study the following changes were seen: acetone in the exhaled air increased; glycolysis and lactate dehydrogenase enhanced; catalase decreased; changes of acid-base equilibrium manifested as metabolic acidosis of varying degree. The use of exercises of different workloads showed that those at 50% VO2max were most beneficial.

Acid-Base Equilibrium↗