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Biomedical subjects

I T Ivanov

Publications and source records attributed to I T Ivanov.

24 records · Page 2Linked to original sources

[Comparison of acid and alkaline hemolysis mechanisms in human erythrocytes].

A comparative analysis of the mechanisms of base- and acid-induced hemolysis was performed. The results obtained indicate the transport of base equivalents through the anion exchanger during the initial phase of base-induced hemolysis, followed by oxidative stress on cellular membranes and hemolysis. It was shown that the Ellman's reagent (0.4 mM) did not prevent NaOH-induced hemolysis but fully inhibited HCL-induced hemolysis. The inhibition of acid-induced hemolysis was accompanied by the crosslinking membrane proteins, presumably through their acylation. The addition of SH-reducing reagents (cystein, dithiotreitol and, to a lesser extent, albumin eliminated the crosslinkage of membrane proteins and impaired the permeability barrier. It was found that crosslinkage could not prevent the oxidative damage of membrane proteins but was able to preserve the permeability barrier. Based on these results, it was concluded that the barrier impairments associated with acid-induced hemolysis were due to the aggregation of membrane proteins that underwent oxidative damage.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

[The effect of chaotropic anions on the course of acid hemolysis in an isotonic sugar medium].

The influence of CNS-, ClO4-, NO3-, and SO4(2-) on the kinetics of acid hemolysis of erythrocytes of man, lamb, rat and rabbit was investigated. These chaotropic anions exercised strong and specific effects on the extent and time course of acid hemolysis under such conditions. In accordance with the intensity of the exercised antihemolytic effect, these anions formed a row coinciding with the Hoffmeister's row of their chaotropic action. The results demonstrate the impact of intermolecular interactions disturbance applied mainly on the cell membrane on the mechanism of acid hemolysis.

Animals↗

[Aggregation of denatured membrane proteins--the initial stage of acid hemolysis].

Influence of some sulfhydryl reagents on kinetics of acid hemolysis has been investigated. The results obtained indicate that the mechanism of acid hemolysis includes aggregation of some denatured membrane integral proteins, following the intermolecular disulfide bond formation. A suggestion is made that in this hemolysis-inducing aggregation free SH-groups containing proteins only take place.

Hemolysis↗

[Kinetics of acid hemolysis in an isotonic sugar medium].

The kinetics of acid hemolysis of human erythrocytes suspended in isotonic sucrose media was investigated. Three successive changes on the curve of the suspension extinction derivative were discriminated and characterized as changes due to morphological transformation, swelling and lysis of the cells. The change due to the reversible morphological transformation could develop in two opposite directions depending on some conditions. The cell swelling was apparently induced by the protonization of hemoglobin with protons entering through the cell membrane. The phases of cell swelling and lysis partly covered each other by isotonicity, but at higher tonicities they were completely separated. These results demonstrate the increased informability of the method applied under such conditions.

Culture Media↗

[Use of methods of derivative conductometry and photometry for assessing the structure of a cellular suspension].

Experimental proofs for the possibility of studying the dynamical structure of rotatory moving erythrocyte suspension with the methods of derivative conductometry and photometry are presented. The amplitude of the recorded impulses was proportional to the cell concentration and the angle velocity, and strongly depended on the shape of the suspended cells.

Cell Movement↗