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V V Egorov

Publications and source records attributed to V V Egorov.

At least 19 recordsLinked to original sources
PubMed2000

[Effect of surface-active agents (SAA) on peroxidase activity. III. Effect of nonionic SAA].

The effect of a series of nonionic surfactants on the initial rate of the peroxide oxidation of 5-aminosalicylic acid in solution catalyzed by horseradish peroxidase was studied. As the surfactant concentration increases, the peroxidation rate first increases, then decreases, and the increase/decrease cycle is repeated. The primary increase may be induced by a change in properties of the medium under the action of surfactants, and the following decrease, by the enzyme inhibition. The secondary increase may be explained by a change in the enzyme conformation and an increase in the accessibility of its active site for the substrate due to the immobilization of the protein in the surfactant aggregates, whereas the secondary decrease, by a shielding of the protein with these aggregates.

Catalysis↗
PubMed2000

[Effect of surface-active agents on peroxidase activity. IV. Effect of lipids and fatty acids from milk].

The effect of surfactants, lipids and fatty acid salts isolated from cow milk on the activity of heme-containing horseradish peroxidase in solution was studied. As the surfactant concentration increases, the rate of the enzymic reaction successively decreases, increases, and again decreases, down to zero in the case of the fatty acid salts. The initial deceleration of the reaction rate results from the enzyme inhibition. The subsequent increase is caused by an improved accessibility for the substrate and the enhanced activity of the catalytic site of the enzyme due to its immobilization in the surfactant aggregates. A shielding of the protein by these aggregates can explain the secondary deceleration of the enzymic reaction rate. The general character of the dependence is similar and does not depend on the surfactant structure for a series of fatty acid salts and phospholipids; however, it is quite different in the case of cholesterol and sphingomyelin.

Animals↗
PubMed2000

Features of the behaviour of double-chained cationic surfactant monomer in a monolayer at the water-gas interface.

We studied the formation of a double-chained cationic monomer, N,N-diallyl-N-cetyl-N-dodecyloxycarbonyl methylammonium bromide, in a monolayer at the water-gas interface. An increase in surface pressure induced the transition from the liquid-expanded to liquid-condensed state with tail-packing and then head-packing of the monomer, which was accompanied by a decrease in the mobility of monomer molecules. An increase in the ionic strength of the subphase led to the compression of the layer, and addition of ethanol or detergents caused its dilution. Polyethylene glycol and polyacrylic acid induced the formation of a complex between the monomer and polymer.

Biophysical Phenomena↗
PubMed1998

[Effect of surfactants on peroxidase activity. I. Effect of anionic surfactants].

The effect of various anionic surfactants on the initial rate of 5-aminosalicylic acid peroxidation with horseradish peroxidase was studied. With increasing surfactant concentration, this rate first decreased, then increased, and again decreased. We conclude that these changes were due to an inhibition of the enzyme, a subsequent change in the enzyme conformation accompanied by the enhanced accessibility of its active site to the substrate, and the final protein denaturation, respectively.

Anions↗
PubMed1998

[Effect of surfactants on peroxidase activity. II. Effect of cationic surfactants].

The effect of various cationic surfactants on the initial rate of the 5-aminosalicylic acid peroxidation with horseradish peroxidase was studied. With increasing concentration of the surfactant, the rate first increased and then decreased. We attributed these changes to a primary activation of the enzyme and/or an increase in the concentration of the substrate in the region of the active site and to the subsequent inactivation of the protein with surfactant followed by its denaturing, respectively.

Cations↗
PubMed1991

[A comparative analysis of the action of zootoxins on the isolated heart].

A comparative analysis of cardiotropic activity of toxins has been studied in experiments on isolated heart of the poisonous animals from different systematic groups living on the territory of the USSR: reptiles (the venom of cobra, Vipera lebetina, Ancistrodon blomhoffi), amphibian (the venom of Bufo, Bombina, salamander), arachnids (the venom of Apis, Scolopendra, scorpion). The specific cardiotropic activity of the scorpion and Bufo venom has been discovered. The mechanisms of the cardiostimulative activity of scorpion venom have been found to be due to the activation of cellular adrenoreactive structures, and the Bufo venom to the activation of the intracellular calcium. The prospects of zootoxins using in cardiology for development of cardiotonic drugs and modelling the pathologic states in blood circulation system is substantiated.

Amphibian Venoms↗
PubMed1983

[Disorders of neurohumoral regulation in rats exposed to the poison of the scorpion Buthus eupeus].

The intraperitoneal injection of Buthus eupeus to rats (2,5 mg/kg) results in increasing of catecholamines and cyclic nucleotides content in blood. The hyperinsulinemia is observed simultaneously with the development of hyperglycaemia. It is believed that the activation of the cyclic system is a key mechanism of the neuro-humoral disturbances of homeostasis in case of scorpion venom influence.

Acute Disease↗
PubMed1981

[Changes in the levels of 3',5'-cAMP and 3',5'-cGMP in brain and heart tissues after exposure to toxins of Buthus eupeus scorpion venom].

Toxins isolated from Buthus eupeus scorpion stimulated the generation of cAMP and cGMP in mouse cerebellar and forebrain slices, as well as in isolated guinea-pig heart. Pharmacological analysis of neurotropic and cardiotropic effects of toxins has ascertained the relationship between the increased level of cyclic nucleotides and catecholaminergic and cholinergic effects of toxins.

Animals↗
PubMed1979

[Possibility of using the BI-3 jet injector for gamma globulin administration].

The results of weighing glass flasks before and after "shooting" preparations varying in viscosity into these flasks from type BI-3 jet injectors indicated that the ejected dose of gamma globulin corresponded to the preset value. Studies carried out by means of radioisotyope technique with the use of Tc99m showed that the intramuscular injection of gamma globulin with type BI-3 jet injector resulted in 75% of the preset dose penetrating the body. For this reason in mass vaccination against Botkin's disease the dose of the preparation in the injector should be increased by 1/3.

Evaluation Studies as Topic↗
PubMedDate not supplied

[Impact of disorders in blood rheology on progress of glaucoma in patients with stable normalized intraocular pressure].

Comparative study of blood rheology in 53 patients (76 eyes) without stabilization of primary glaucoma with normalized intraocular pressure (group 1) and in 43 patients (61 eyes) with stabilized course (group 2) showed significant differences between the two groups. In group 1 erythrocyte aggregation was increased in 79.3% and their deformability decreased in 88.7%; high content of Willebrandt's factor was detected in 83% patients. By contrast, in group 2 these shifts were detected in only 20.9 and 23.3% patients, respectively, while the content of Willebrandt's factor was normal. The detected rheological shifts were in high correlation with an unstable course of glaucoma, and their severity may serve as a prognostic sign for predicting the course of glaucoma in patients with normalized intraocular pressure.

Adult↗
PubMedDate not supplied

[The effect of neurohumoral factors of the sympathoadrenal system on the results of cataract extraction with intraocular lens implantation in diabetic patients].

Effect of the sympathoadrenal system (SAS) on the results of cataract extraction with IOL implantation was studied by analyzing the stress index in 64 patients with diabetes mellitus and 20 reference patients. SAS reaction to surgical stress was abnormal in 34 (53.1%) diabetics. The level of SAS activity, postoperative complications, and kinetics of regenerative repair processes in the cornea were related. In 15 (23.%) diabetics with a low stress index the postoperative period was characterized by frequent inflammations, longer repair of normal corneal homeostasis, and coarse cicatrization. In 19 (29.7%) diabetics with a high stress index after cataract extraction normalization of the corneal homeostatic parameters was delayed and macular edema developed 4.8 times more often.

Adrenal Glands↗
PubMedDate not supplied

[Clinical and pathogenetic features of neurotrophic corneal disorders in diabetes].

The corneal neurotrophic status was evaluated in 110 patients (220 eyes) with diabetes mellitus and in 20 normal controls (40 eyes). Corneal abnormalities (gerontoxon, limb vascularization, punctate keratopathy, endothelial dystrophy, relapsing erosion, corneal ulcers) were detected in 73.6% diabetics. Corneal changes depended on the type, duration, and compensation of diabetes mellitus. Based on the diagnostic markers (threshold sensitivity of the cornea, microcirculatory status, bulbar conjunctiva status, level of lacrimal production, cellular composition of the limb smears impressions, lacrimal levels of catecholamines, hydroperoxides, and lipids), three types of diabetic neuropathy of the cornea were distinguished: vegetative, sensory, and vegetosensory. Corneal changes were associated with signs of diabetic neuropathy in 55.6% cases and with autonomic nervous disorders of the cardiovascular system in 46.9% cases, which evidences a generalized involvement. The detected neurotrophic features of the cornea should be borne in mind when choosing pathogenetic therapy for diabetics with corneal complications and preparing the patients to ocular surgery.

Adult↗