Biomedical subjects

S V Grachev

Publications and source records attributed to S V Grachev.

78 records · Page 5Linked to original sources

PubMedDate not supplied

[The determination of the content of the cholera toxin gene in the composition of the DNA from Vibrio cholerae strains by means of the nested polymerase chain reaction].

The possibility of detecting cholera toxin genes in V.cholerae enterotoxigenic strains by the method of "nested" polymerase chain reaction with the use of primers on the DNA area of operon ctx of AB genes. The possibility of the detection of several V.cholerae cells by this method was shown with the use of a series of bacterial lysate dilutions. The newly developed test system for the detection of cholera toxin gene on the basis of the analysis of bacterial lysates of V.cholerae nontoxigenic strains, as well as Escherichia coli toxigenic and nontoxigenic strains, was shown to be highly specific.

Base Sequence↗

PubMedDate not supplied

[Ability of carbon dioxide to inhibit generation of superoxide anion radical in cells and its biomedical role].

The study was carried out on blood phagocytes and alveolar macrophages of 96 persons, cells of inner organs and tissue phagocytes (liver, brain, myocardium, lungs, kidneys, stomach, skeletal muscles), as well as on mitochondria of the liver of 186 non-linear white mice. Generation of active oxygen forms (AOF) was evaluated by various methods with CO2 directly affecting the cells and bioptates and indirectly the whole organism. The results show that CO2 with tension close to that of the blood (37.0 mm Hg) and at higher tensions (60 and 146 mm Hg) is a powerful inhibitor of AOF generation by human and animal cells, as well as by liver mitochondria of mice. The data obtained allow to explain, in terms of AOF role, a number of physiological and pathophysiological (medical) CO2 effects.

Animals↗

PubMedDate not supplied

[The postnatal development of the hemato-C-cellular system in the thyroid of rats sympathectomized with guanethidine].

We used ultrastructural morphometry to examine submicroscopical organization of spatial contacts between the C-cells and perifollicular hemocapillaries in the thyroid gland of 2-, 4-, 12-, 26-, and 52-week-old rats desympathized with guanetidine. We found that desympathization does not affect typology of ultrastructural elements of the hemato-C-cellular complex, and predominant coupling of the vascular pole of the C-cell with peripheral zone of endotheliocyte highly effective in terms of transport. Postnatal changes of certain parameters of the hemato-C-cellular system, however, undergo some statistically significant changes. Under experimental conditions, we observed the formation of hemato-C-cellular contacts simultaneously involving two C-cells.

Aging↗

PubMedDate not supplied

[Carbon dioxide--a universal inhibitor of the generation of active oxygen forms by cells (deciphering one enigma of evolution)].

Studies were carried out on blood phagocytes and alveolar macrophages of 96 humans, on the cells of the viscera and tissue phagocytes (liver, brain, myocardium, lungs, kidneys, stomach, and skeletal muscle), and liver mitochondria of 186 random bred white mice. Generation of the active oxygen forms was determined using different methods after direct effect of CO2 on the cells and biopsies and indirect effect of CO2 on the integral organism. The results obtained suggest that CO2 at a tension close to that observed in the blood (37.0 mm Hg) and high tensions (60 or 146 mm Hg) is a potent inhibitor of generation of the active oxygen forms by the cells and mitochondria of the human and tissues. The mechanism of CO2 effect appears to be realized, partially, through inhibition of the NADPH-oxidase activity. The results are important for deciphering of a paradox of evolution, life preservation upon appearance of oxygen in the atmosphere and succession of anaerobiosis by aerobiosis, and elucidation of some other problems of biology and medicine, as well as analysis of the global bioecological problem, such as ever increasing CO2 content in the atmosphere.

Aerobiosis↗

PubMedDate not supplied

[The efficiency of the calcitonin-transporting activity of the hemato-C-cellular system in the thyroid gland].

The efficiency of hemato-C-cellular transport of calcitonin into the systemic blood flow was evaluated by the methods of statistical modelling. The linear regression model obtained on 36 rats suggests essential predetermination of the serum concentrations of calcitonin (CT) by the intensity of incretory activity of the thyroid parafollicular epithelium: CT = 13.733+ (0.318 Nvsg; rxy = 0.830; p < 0.001 (Nvsg is numerical density of the sublemmal granules on the C-cells vascular pole). At the same time, the resulting index (CT) depends not only on Nvsg. This index is also influenced by the factors not controlled by the model, such as Hemato-C-cellular delay of calcitonin. These factors determine each certain proportion of the error of prognostication of the calcitonin serum content according to Nvsg. A covariation model CT = bNvsg was plotted in order to determine the total influence of uncontrolled factors. Its error of prognostication was subject to analysis of variance and a confidence interval of biological accessibility of endogenous calcitonin was calculated (73% < FCT < or = 100%; p > or = 0.95). The results obtained suggest the absence of essential intrathyroid loss of calcitonin at the transinterstitial and transmural stages of hemato-C-cellular hormone transfer.

Animals↗

PubMedDate not supplied

[Study of the endogenous calcitonin transport in the rat thyroid gland].

Regression analysis revealed a significant correlation between Nvsq and calcitonine. The regression model was then transformed into a covariation one to establish: 1) probability of all calcitonine molecules moving across the C-cell-blood barrier into the blood, 2) confidence interval of endogenous calcitonine bioavailability, and 3) estimate of the period of calcitonine half-retention by the C-cell-blood barrier.

Animals↗