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Biomedical subjects

K N Novikov

Publications and source records attributed to K N Novikov.

28 records · Page 2Linked to original sources
PubMedDate not supplied

[Protein-lipid interactions during lipid peroxidation in photoreceptor membranes].

It has been shown that chemical modification of hydrophobic lipid phase (lipoperoxidation) of outer segments membrane discs of frog retina rods brings about weakening protein-lipid interactions in the photoreceptor membrane. As a result of this extraction of rhodopsin with anion detergent (sodium cholate) in the concentrations not exceeding the critical concentration of micelloformation increases, and spontaneous release of rhodopsin into water phase is observed. At the same time the number of phospholipid molecules extracted in lipoprotein rhodopsin complex from the membranes of outer segments decreases 3-4-fold.

Animals↗
PubMedDate not supplied

[Spontaneous and induced autoxidation of phospholipids during conformational rearrangements in outer segment membranes of frog retinal rods].

Kinetics of spontaneous and induced by the system Fe+++ascorbate peroxide oxidation of lipids in the membranes of outer segments of frog retina rods has been studied. Free radical oxidation of phospholipids passes the same stages as liquid phase oxidation of alkenes. Docosahexaenoi fatty acid residue of phosphatidyletanolamine is the main substrate of autooxidation. The structural organization of photoreceptor membranes is the factor which controls the reaction rate of peroxide oxidation; and reconstructions in membrane organization (at rhodopsin photolysis) result in the changes of autooxidation rate of phospholipids in the membrane.

Animals↗
PubMedDate not supplied

[Participation of phospholipases in the "repair" of photoreceptor membranes subjected to peroxidation].

Results are presented showing that Ca++-activated endogenous phospholipases are able to catalyze hydrolysis of hydroperoxydiacyglycerophosphatides with subsequent formation of monoacyglycerophosphatides and free hydroperoxides of fatty acids in frog rod outer segment membranes. The role of endogenous phospholipases in the mechanisms of repair of photoreceptor membranes subjected to lipid peroxidation, as well as in "molecular substitution" of phospholipids under membrane renewal is discussed.

Animals↗
PubMedDate not supplied

[The regulation of cell volume: the mechanisms, coupled cellular reactions and pathophysiological significance].

A review contemplates as a whole the problem of regulation of the cellular volume. The first part of the review considers the influences inducing alterations in the cells volume on account of changes in the tonicity of extracellular milieu and cytoplasm. The review elucidates the ways of implementing the fast and slow regulatory volume increase as well as decrease (RVI, RVD). The volume increase seems to enhance cells' proliferative ability due to activation of ions transport. The volume decrease needs further investigations. The last chapter of the review considers pathophysiological significance of the volume regulation in hyponatremia, diabetes, neutrophil activation.

Anemia, Sickle Cell↗
PubMedDate not supplied

[The ATP content of the neutrophils and whole blood in the inhabitants of regions in the Altai Territory subjected to nuclear testing exposure].

The bioluminescent method was used in the studies of the influence of ionizing irradiation and/or xenobiotics on the content of ATP in RBC and neutrophils of rats, and in whole blood and neutrophils of 80 examined women of Altai Region exposed to ionizing radiation during a series of nuclear tests in Semipalatinsk in 1949-1965. Deviations from the normal ATP content were measured with due to account of the natural variability of a given metabolite. For rats, deviations from the content of ATP in erythrocytes were short-term, those in neutrophils were long-term. For people, a statistically significant increase in the content of ATP in neutrophils as compared to the control was observed. A non-linear correlation between the content of ATP in neutrophils and the calculated dose of radiation was observed. An increase in the ATP content in whole blood, with regard to the control, was not statistically significant for all groups of examined persons.

Adenosine Triphosphate↗
PubMedDate not supplied

[Role of lipid composition in the kinetics of free radical lipid oxidation in photoreceptor membranes].

The initial rate of lipid peroxidation (LPO) in photoreceptor membranes (PRM) of walleye pollock is 1.8--2.3 times higher than in frog PRM. Rhodopsin bleaching leads to an increase of LPO initial rate in PRM while having no effect on LPO in walleye pollack PRM. The content of unsaturated fatty acids in walleye pollock PRM is 1.4 times greater than in frog PRM. It is suggested that differences in LPO kinetics in PRM of walleye pollack and frog are caused by the differences in the lipid composition of the membranes (primarily by a high level of phospholipid molecular species with two unsaturated fatty acid residues in walleye pollock retina rod outer segments).

Animals↗