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Y M Lopukhin

Publications and source records attributed to Y M Lopukhin.

8 recordsLinked to original sources

Changes in surface charge of low-density lipoproteins during oxidative modification.

The negative surface charge of low-density lipoproteins increased during their oxidative modification induced by autooxidation at 37 degrees C. The degree of changes depended on the time of autooxidation: the surface charge remained practically unchanged after short-term oxidation (6-h incubation), but then progressively increased and after 24-h oxidation it 2-fold surpassed the initial level. Long-term incubation of low-density lipoproteins in the presence of EDTA inhibiting lipid peroxidation did not change their surface charge. These changes probably contribute to atherogenic activity of oxidized low-density lipoproteins. The degree of oxidative modification of low-density lipoproteins was precisely estimated using fluorescence probes.

Anions↗

Chemiluminescence assay of the antioxidant state in patients with atherosclerosis.

We evaluated antioxidant state of 62 patients with coronary heart disease and 47 patients with obliterating atherosclerosis of lower extremities by peroxide-depend chemiluminescence and inhibition of azo-initiated chemiluminescence and hydrogen peroxide-hemoglobin-luminol chemiluminescence system. The flash amplitude of peroxide-dependent chemiluminescence in the plasma from patients was 32% below the control. Antioxidant activity of the plasma from patients was higher than in healthy individuals by 33 and 27% depending on the type of free radical-generating systems. The increase in antioxidant activity was most pronounced in patients with combined pathology: coronary heart disease complicated by obliterating atherosclerosis. These results explain the decrease in peroxide-dependent chemiluminescence of the plasma and whole blood in patients with atherosclerosis compared to that in healthy individuals.

Antioxidants↗

Effects of low-density lipoproteins on blood coagulation and fibrinolytic activity.

In vitro experiments showed that copper-oxidized low-density lipoproteins activate factors of the prothrombin complex in the whole blood and inhibit fibrin generation in both blood and plasma. Moreover, oxidized low-density lipoproteins inhibit fibrinolysis and impair the structure of fibrin clot, which results in hypercoagulation.

Blood Coagulation↗

Conformational changes in albumin molecule: a new response to pathological process.

A new fluorescent test developed at the Institute of Physicochemical Medicine (Ministry of Health of the Russian Federation) allows to determine not only blood concentration of albumin, but also to evaluate the state of its molecule. The test is feasible and enables express-analysis of the plasma and serum without fractionation and other preliminary procedures. This test reveals abnormalities in albumin molecule caused by toxic metabolites or conformational changes. Many diseases are accompanied by conformational changes in albumin, while its concentration often remains unchanged. Changes in albumin conformation can serve a diagnostic and prognostic criterion in some pathologies.

Blood↗