Ukrainskii biokhimicheskii zhurnal (1978)最新文献

Thermogravimetric studies of egg yolk lecithin water dispersion were carried out under conditions similar to those previously used in DSC studies of model biomembranes. For comparison, water dispersion of Na-DNA from calf thymus was studied in a parallel series. In both cases several distinct states of associated water were observed. The biomolecule/water stoichiometry obtained is compared with respective literature data.

Radiation-induced activation of the nuclear and cytosolic regulatory pathways, involvement of transcriptional factors and calcium in apoptotic signal transducing, DNA fragmentation at the different stages of apoptosis are discussed. The data on bcl-2 action in preventing calcium signal and apoptosis in lymphoid cells are presented.

It was shown that vitamin E decreased the stimulating role of oxidative burst activators which influenced on Ca(2+)-dependent mechanisms (A23187, verapamil, FMLP). Jointly addition of this vitamin and blood plasma contained tocopherol-binding proteins influenced on mechanisms associated with protein kinase C. It was shown that Ca ions can also take part in tocopherol's action on blast transformation of lymphocytes.

It is cited results of investigation of amino acid composition of blood serum of harp seal pups in the first days after catch adaptation in conditions of oceanarium. It is shown that changes of amino acid composition are most expressed in the first ten-day period of observation and manifest itself by increase of free amino acid concentration at the expense of their endogenous entrance in blood. At the same time it was detected amino acid imbalance which is conditioned by stress of animals. Results of investigation witness intensification of protein catabolism under conditions of stress. Because of it it is necessary to correlate protein metabolism for prophylaxis of hypotrophy seal pups.

We have examined in vivo capacities of two C27-steroid hormones-phytoecdysteroid ecdysterone (20-hydroxyecdysone, 10(-8)M) and calcitriol (1 alpha, 25-dihydroxyvitamin D3, 10(-12)M), as a modulators of neutral lipids hydrolysis in the brain and heart cells. Severe lines of evidence indicate that both hormones may acts as positive regulators of cholesterol esters and triacylglycerol hydrolysis in early (0.5-30 min) pregenomic phase of its actions, yielding known (DAG, free polyunsaturated fatty acids) and possible (free cholesterol) lipid second messengers.

It is established, that certain variants of replacement of chromosomes performed on wild (C-S, D) and mutant (cn, vg) lines as well as continuous backcrosses, leads to the change of heat resistance and activity of F- and S-allozymes of ADH in tissues of synthesized forms of drosophila. But nevertheless, the electrophoretic mobility of allozymes does not change. It is assumed that post-translated modifications of ADH play the important part in processes of phylogenetic adaptation of Drosophila melanogaster.

Kinetic study made in vitro showed that rat liver mitochondria contain calcium-activated neutral proteinases with activity optimum of total preparation within micromolar concentrations of calcium ions.

Molecular mechanism of pathogenesis of psoriasis related with intensity of formation of oxygen active forms high concentration, depends on balance of pro-oxidant and antioxidant systems activity and leads to quantitative changes of toxic agents of peroxidation processes in blood. Observed results show disorders in Cu, Zn-superoxide dismutase activity and contents of ceruloplasmin, transferrin and new revealed pro-oxidant metalloproteins-cytochromes b558(III), b558(IV), b5, O2(-)-generating lipoprotein suprol and indicate of disturbances in intensity of lipid peroxidation processes. They are considered as obligatory but not specific link in molecular mechanisms of different etiology of oxidative stress formation being as important argument in pathogenesis of various diseases as well as psoriasis.

For the identification of mirror type internal symmetry centers in amino acid sequences (AASs) the new method, named by the method of internal symmetry scanning, was developed. The method, contrary to earlier ones, can be used for analysis of large clusters of primary structures of related proteins. The internal symmetry centres, containing both one and two amino acid residues, can be identified rapidly and effectively by the method. Additionally, the new method allow to estimate quantitatively the homology of AASs, which are antiparallel to relation of the centres. The different modifications of the method can be used for revealing of both high conservative and unequal symmetrical structures in AASs of proteins. Usually the structures coincide with functionally important regions of protein molecules. The method was used for investigation of primary structures of members of heterotrimeric G-protein a a-subunit superfamily. The positive correlation between conservativity of primary structure and distribution of mirror type internal symmetry centres was shown.

As a result of the experiment on the laboratory animals under the continuous administration of acetaldehyde there has been revealed the latter as inducing the aldehyde dehydrogenase activity in the cytosol fraction of the cerebral structures/hypothalamus, mid-brain and new cerebrum cortex/as well as in the levels of biogenic amines/noradrenaline and 5-hydroxytryptamine/in the same structures while forming experimentally in the laboratory animals the alcoholic dependence under acetaldehyde alcoholic dependence. The work displays some changes of alcohol dehydrogenase and action.