Izvestiia Akademii nauk SSSR. Seriia biologicheskaia最新文献

Based on literature data on effects of various preparations on the glycolysis in tumor and normal cells, a glycolytic molecular biochemical marker is proposed to screen chemical substances as potential antitumor drugs. A glycolytic specificity was noted in tumor cells which was regarded as a criterion for distinction of tumor cells from normal ones and among various histotypes of tumor cells as well as for the selective sensitivity of tumor cells to a substance. 17 of 38 substances tested were observed to inhibit glycolysis in tumor cells. The testing chemical substances for an antitumor activity with application of the glycolytic marker is recommended. A possibility is discussed of applying the marker for testing potential antitumor drugs, their individualization, and genetic typing.

The energetic state and activity of polyamine-synthesizing system of E. coli were studied under conditions of aerobic-anaerobic and pH transitions, nutrition shifts, osmotic and heat shocks. The electron microscopy of cells showed a correlation between cell physiological state and nucleoid ultrastructure. The role of energetic status and polyamines in the regulation of DNA supercoiling is discussed which is a putative cause for the changes observed in the nucleoid ultrastructure.

The effect was studied of mixed cys- and 3-, 4-, 5-, 6-nomial cycloalkylamines or substituted 2-, 3-, 4-methyl- and 4-hydroxycyclohexylamines as well as similar carboxylatocomplexes containing anions of malonic hydroxymalonic, succinic and malic acids on the growth of corn sprout roots. Complexes with non-substituted cycloalkylamines possessed the most pronounced cytostatic activity. Complexes with substituted cyclohexylamines were less active than their non-substituted analogue as well as other complexes with lesser size of cyclic substitute. The cytostatic activity of carboxylatocomplexes, as compared to that of chlorocomplexes, generally manifested itself at ten times higher concentraiton and depended not only on the size of cycloalkylamine but also on the nature of acidoligand.

Parameters of ideal circadian cycle were compared with those of a circadian cycle composed of near-hour fluctuations. The integral cycle was optimized by the algorithm of matrix random search studying the approximation of its parameters to the ideal cycle after the phase shift of the latter. Computer calculations revealed a low efficiency of the search by fluctuation amplitude. The search by phase and frequency was effective in a narrow range of changes and needed time. The average level of fluctuations tuned up practically immediately: ideal and optimized curves coincided in all points. Examples of interactions between day, near-hour and shorter cycles are cited.

Novel biologically active substances were obtained from nonpathogenic for humans and free-living protozoa: Crithidia oncopelti, Trypanosoma lewisi, and Astasia longa. There were studied conditions of biosynthesis, composition and biological activity of the total lipid fraction from the protozoa species, sucrose ethers and fatty acids, the latter were isolated from A. longa--(astazilide preparation), reserve beta-1,3 glucan from A. longa (astazian preparation), and fraction of surface glycophospholipids and peptides from Crithidia oncopelti (GLP preparation). Two of three preparations studied (astazilide and GLP) are the complexes of natural substances with certain composition. Conditions of the protozoa cultivation were developed to provide standardization of the complex composition. Division of the complexes into separate components decreased or abolished the biological activity. It was established that the substances studied modify biological reactions, that is exert a systemic effect. They may be used for inhibiting the growth of experimental tumors and preventing the metastatic spreading in tumor-carrier animals. The substances obtained belong to the group of nonspecific stimulators for cellular immunity which can be used in medicine, veterinary medicine, food industry, pharmacologic industry and cosmetology.

In the present work, the nature of an anticoagulant from Philipendula ulmaria was studied. A method for purification of this anticoagulant was developed. Using diverse methods it was shown that the molecular weight, data on element (sulphur, nitrogen, and hydrogen) content, spectral characteristics in the infrared region of the spectrum, and electrophoretic properties of the product indicate its similarity to heparin of animal origin.

There is a definite relation between the state of dolphin's health and the abundance of bacterial associations developing on the skin surface around the dorsal fin. The disease was accompanied by an increase in bacterium amount more than fourfold due to the enhancement of staphylococcus and pseudomonad number. The development of dystrophy in the animal resulted in a threefold decrease in bacterium number. Pseudomonas aeruginosa dominated in this case. In the vaginal mucose of female, the development of bacteria had an oscillatory character and was correlated with the dynamics of leukocyte number against the background of morphologically diverse epithelial cells discharged in different periods of observation. Periods of the abundant bacterium development were connected with the cyclic recurrence of sexual (estrous) processes in the female organism.

The results are presented of investigations on determining the functional state of mineralocorticoid receptor apparatus in rat kidney at diverse stages of the reflex renal dystrophy per se and that against the background of renal denervation along with propranolol injections produced at different terms following the disturbance of nervous system trophic function. It was shown that simultaneous blockade of neuroconductory and humoral pathways of pathological stimulus transmission from central end of cut ischiatic nerve to the kidney prevents the development of trophic disturbances in the organ as tested by the state of mineralocorticoid receptors, to a more extent than the blockade of neuroconductory pathway only. The activity of molecular structures which determine the mineralocorticoid reception in cells of renal tubules seems to be controlled both by central neuroconductory and humoral mechanisms.

This is a brief review of different ideas on the mechanism of cell malignization united by the mitochondrial conception of carcinogenesis. According to this conception, primary trigger factors of carcinogenesis (free radicals, carcinogens, heat fluctuations) induce damage to mitochondrial DNA and membranes that results in the rearrangement of cell energy metabolism to glycolytic type and disturbance of mitochondrial structure and reproduction. The injured part of mitochondrial DNA incorporating into nuclear DNA induces activation of oncogenes, appearance of oncoproteins and malignization of cells.