Heterologous transformation in Bacillus subtilis. 1. Transmission of DNA of the R1drd19 plasmid]

Bac. subtilis 168 (BD-25) cells were infected with DNA of plasmide R1drd19 isolated from E. coli strain; transformants resistant to streptomycin (500 microgram/ml) and kanamycin (40 microgram/ml) appeared with the frequency of 2.10(-6). These transformants retained resistance to the mentioned antibiotics stably. A satellite DNA peak was revealed in centrifugation in the density gradient of cesium chloride with ethidium bromide. It was possible to infect cells of Bac. subtilis 168 (BD-25) with plasmide DNA isolated from the transformants. Plasmide transduction with the aid of phages AR9 and PBSI multiplied on the transformant strains was also effected. Physico-chemical analysis of the transformed plasmide DNA was conducted; its molecular weight was determined.     

Incorporation of amino acids into liver and serum proteins during prolonged administration to animals of ethanol and cholesterol

The synthesis of soluble liver proteins and amino acid incorporation into blood serum proteins were studied in guinea pigs which were daily administered ethanol and cholesterol during 3 months. 9 fractions obtained by electrophoresis in polyacrylamide gel were analyzed. It has been found that ethanol and cholesterol in the liver suppress the synthesis of 4 out of 9 recorded protein fractions. In the serum the ethanol effect against a background of the cholesterol administration is characterized by a sharp decrease of specific radioactivity of albumins while the quantity of the protein fraction is unchanged. These results together with the data available in literature on the ethanol suppression of proteolysis suppose that the joint effect of ethanol and cholesterol is accompanied by a decrease in the blood serum albumin decomposition.     

Prevention of disorders of cardiomyocyte ultrastructure in experimental myocardial infarction in immobilization-induced stress by administration of thyroid hormones

In the experiment, carried out on 48 non-inbred male rats ultrastructural changes in cardiomyocytes in non-ischemized parts of the heart at experimental infarction of myocardium under conditions of immobilization stress have been studied, as well as possibility to correct these changes by means of thyroid hormones. The stress intensifies dystrophic processes, developed outside the infarction zone, increases the mass of the necrotized tissue, essentially decreases the areas occupied by mitochondria and myofibrils, as well as their ratio in the section area. Small doses of thyroid hormones prevent the heart from the damaging effect of the stressor: decreasing area; occupied by mitochondria, myofibrils and their relation in the section, as well as they stimulate intracellular regenerative processes (accumulation of polymorphous mitochondria with clearly manifested cristae, membranes of the endoplasmic reticulum) and decrease the myocardial necrotized zone). Thus, structural lesions, resulted from the effect of ischemic necrosis and stress, can be prevented by small doses of thyroid hormones+.     

Role of heparin in the formation of food lipemia

Influence of endogenic and exogenic heparin in vivo on the basic forms of serum lipids content: cholesterol ethers, triacylglycerols, free fatty acids; as well as that glycosaminoglycan effect in vivo and in vitro on total lipoproteine lipase (LPL) activity and lecithin-cholesterol acyltransferase (LCAT) activity of human blood serum were investigated on food lipidemia model. The decrease of intercell reserve heparin content and increase of the background and post-heparin levels of blood serum LPL activity were indicated after two hours food load. The role of two factors, endogenic heparin being one of them, in the increase of postprandial LPL activity of blood serum were discussed. At the same time, some inhibition of blood serum LCAT activity two hours after food reception (evidently, as a result of endogenic heparin action) and to a considerable extent inhibition of cholesterol etherification under the action of exogenic heparin in vivo were ascertain. Heparin in vitro (50 U/ml of blood serum) did not influence LCAT and total LPL activities. It was summarised that endogenic heparin is a factor, taking part in lipolysis processes regulation.     

Thyroid hormone prevention of disorders of cardiac contractile function during stress

The depression of cardiac contractility has been observed in rats during the immobilized stress in state of relative physiological rest and maximal load. In the animals pretreated with thyroid after stress the indexes of intensity and rate of myocardial contraction and relaxation didn't differ from the control, and during the maximal load the myocardium was characterized by the less expressed decrease of the structure functioning intensity and the higher rate of relaxation. The data obtained show that the physiological doses of thyroid hormones prevent the myocardium from contractile disorders during stress.     

Prevention of stress-induced changes in coronary autoregulation of vasodilative reserve of the coronary vessels and contractile function of the isolated heart with small doses of thyroid hormones

The possibility to restrict stress disturbances of coronary blood flow and contractile myocardium function with small doses of thyroid hormones has been studied on 46 hearts of female rats isolated by the Langendorff method. It is found that small doses of thyroidin increase the force of systoles and adequately increase relative coronary blood flow, coronary reserve vasodilatation, significantly prevent stress disturbances of coronary autoregulation, the force and rate of the myocardium contraction and relaxation, that restricts disproportion between contractive function and coronary blood flow.     

Ontogenesis of the asymmetry of transcallosal responses in the cat parietal cortex

In acute experiments on 2-24 days old immobilized kittens and adult cats, studies have been made on the development of functional interhemispheric asymmetry of homotopical transcallosal responses in the parietal cortex. It was found that the number of animals with evident asymmetry increases with age. Alongside, with respect to such characters as asymmetry coefficient, mean amplitude of components of transcallosal components and the ratio of zones of direct and inverse domination, the increase in functional interhemispheric asymmetry was observed during the second week of postnatal life of kittens, which was accompanied by the inversion of its sign; in adult cats, the decrease in the asymmetry up to its complete absence was found. The data obtained are discussed with respect to peculiarities of the development and functional properties of the associative parietal cortex in cats.     

The enhancement of body resistance to combined exposure to immobilization and cold with thyroid hormones]

In experiments on 123 male rats have been found that the combination of immobilizing and cold (4 degrees C) stresses during 6 hours results in the formation of 4.5 gastric mucosa ulcers in every rat, marked activation of lipoperoxidation and depression of antioxidant activity of myocardium, significant increase of relative mass of adrenal glands, decrease of spleen mass and death of 80% animals accompanied by the reduction of concentration of thyroid hormones in blood serum and hypothermia (to 28 degrees C). The prestress injection of small doses of thyroidine decreased of mucosa defect rate and the number of ulcers to 2.8, made less marked the changes of relative mass of adrenal glands and spleen and the changes of concentration of thyroid hormones in blood serum, significantly limited the activation of lipoperoxidation, depression of power in antioxidant systems of myocardium, hypothermia (to 32.5 degrees C) and significantly increased the survival rate (to 70%).     

Changes in the serum protein composition in experimental hypercholesterolemia

Cholesterol accumulation, quantitative changes and composition of lipoproteins, total proteins of blood serum and protein fractions obtained by acid extraction are studied in hypercholesterinemia dynamics in rabbits. It is found that the initial period of cholesterinosis in blood serum is marked by an increased content of total proteins and proteins extracted by acid followed, however, by substantial lowering of the level of these compounds. The proteins obtained by acid extraction are characterized by more explicit changes. This permits assuming their important role in the pathogenesis of hypercholesterinemia. The obtained results make it possible to state that the investigated proteins possess the alkaline properties. The data available in literature on the ability of alkaline polypeptides to bind cholesterol permit assuming that the investigated proteins have the same properties and, hence, can participate in the molecular mechanisms of cholesterol transport as well as in the processes of synthesis and transformations of separate classes of lipoproteins.