Influence of ATP on Ehrlich ascites carcinoma cell free cytoplasmic calcium concentration in the course of tumor growth.

The changes in free cytoplasmic calcium concentration ([Ca2+](in)) and the effects of extracellular ATP on [Ca2+](in) have been studied in Ehrlich ascites carcinoma cells in the dynamics of their growth. The basal level of [Ca2+](in) and the effects of ATP on the ascites cells were determined by the stage of tumor growth and depended on the content of reactive oxygen species (ROS). The sharp increase in basal and ATP-induced elevation of [Ca2+](in) levels were observed at the 12th day of ascites cell growth.

Kinetic characteristics of the theoretical ecosystems with different extent of openness.

In this paper, the influence of the extent of openness of ecosystem that is defined by the dilution rate, which characterizes the extent of flowage of the pond, on the intensity of the biotic circulation in ecosystems with different regulation types, number of trophic links and extent of closing has been investigated. We considered open systems, we took into account the return of the limiting substances, such as nitrogen and phosphorous, into the cycle by degradation of detritus and products of vital functions of consumers. It was shown by the numerical calculations that the increase of the dilution rate in without recycle ecosystems leads to increase of the net primary production up to the maximum value corresponding to the two-link trophic chain (biogenic substance and producer) and then, to gradually decrease.

Direction of fluid transport in the lens.

The direction of fluid flow in rabbits was studied in vivo by the distribution of fluorescein in eye structures. Fluorescein was administered into the central part of the lens. Fluorescein migrated from the anterior to posterior surface of the lens and then appeared in the vitreous body.

[Information value of various trinucleotides of some genetic systems].

New method to reveal the sites in genomes obtaining the high information capacity is developed. A distribution of those sites of the length 3 among 16 viral genomes and 11 bacteriophages genomes has been studied. It is shown that some triplets with high information capacity occur in a family of relatively close genomes with the increased frequency.

Effect of alcoholic intoxication on water content and activity of Na,K-ATPase and Ca-ATPase in rat brain.

We studied the effect of 2-week alcohol intoxication on water exchange and activity of Na,K-ATPase and Ca-ATPase in rat brain. Alcohol intoxication increased water content in the brain due to cell hyperhydration. It is assumed that hyperhydration results from increased Na+ content in cells due to inhibition Na,K-ATPase activity, which in turn is caused by activation of lipid peroxidation under the effect of ethanol.

Function of Ca-pump in sarcoplasmic reticulum of rat myocardium during adaptation to electromagnetic field.

We studied the effect of adaptation to electromagnetic field on functional state of Ca-pump in sarcoplasmic reticulum, intensity of lipid peroxidation, and energy metabolism in rat myocardium. Membrane viscosity was assessed in crude preparation of myocardial sarcoplasmic reticulum. Adaptation to electromagnetic field did not change the rate of endogenous respiration, including ouabain-sensitive respiration, but potentiated coupling between catalytic activity and Ca-transporting capacity of Ca-pump.

Effects of potassium halides on bacterial bioluminescence.

The effects of potassium halides KCl, KBr and KI on NADH:FMN-oxidoreductase-luciferase bioluminescent coupled enzyme system were studied. The influence of salt additions on bioluminescence intensity and bioluminescence light yield was investigated. The inhibition and activation parameters of the salts were calculated using their dependencies on concentration of the salts.

1-Amino-2-nitraminoethane.

The molecule of title compound, C(2)H(7)N(3)O(2), has a zwitterionic structure. All non-H atoms, apart from the terminal N atom of the NH(3) group, lie in the same plane, with a maximum deviation of 0.056 (1) A for the amine N atom of the nitramine group, whereas the deviation of the terminal N atom of the NH(3) group from the same plane is 1.

5-Nitro-2-nitromethyl-2H-1,2,3,4-tetrazole.

The molecule of the title compound, C(2)H(2)N(6)O(4), consists of three planar fragments, namely a tetrazole ring, a nitromethyl group and a nitro group. The nitro group and the tetrazole cycle are arranged in the same plane, but the planar nitromethyl group is located nearly orthogonal to this plane. The molecules are packed in the crystal via van der Waals interactions.

Nitroguanyl azide.

Crystals of the title compound, nitrocarbamimidoyl azide, CH(2)N(6)O(2), consist of two symmetry-independent molecules and the structure is stabilized by intra- and intermolecular hydrogen bonds. The molecule possesses a nitrimine structure.

The use of bioluminescent biotests for study of natural and laboratory aquatic ecosystems.

A set of bioluminescent tests was developed to monitor water quality in natural and laboratory ecosystems. It consisted of four bioluminescent systems: luminous bacteria, coupled enzyme system NADH:FMN-oxidoreductase-luciferase and triplet enzyme systems with alcohol dehydrogenase and trypsin. The set of biotests was applied for a small forest pond (Siberia, Russia), laboratory microecosystems polluted with benzoquinone and a batch culture of blue-green algae.

3-Nitro-1-nitromethyl-1H-1,2,4-triazole.

The title compound, C(3)H(3)N(5)O(4), consists of three planar fragments twisted in relation to each other, namely a triazole ring, a nitromethylene group and a nitro group. Molecular conformation analysis shows that the first stage of thermal decomposition is a breakage of the H(2)C-NO(2) bond. There are essential conformational differences in the molecule in comparison with semi-empirical calculations.

[Metabolic changes in rat liver in the recovery period after hyperthermic exposure].

The metabolic changes in rat liver were studied during a reduction period after the overheating (25 min, 42 degrees C) using the isolated organ perfusion. First six hours after the treatment were characterised by a decrease of the respiration rate, the activation of glycolysis and an exhaustion of hepatic carbohydrate resources. The development of adaptive reaction resulted in the recovery of respiration rate to 18 h.