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Biomedical subjects

L V Galebskaia

Publications and source records attributed to L V Galebskaia.

At least 19 recordsLinked to original sources
PubMed2005

[The effects of divalent cations on the fibrin clot formation and its lysis].

Hemocoagulation is a Ca(2+)-dependent process, and we suppose that other bivalent cations (BC) can also influence this system. The effects of some BC (Ca2+, Fe2+, Zn2+, Cd2+, Co2+ and Ni2+) on thrombin-induced plasma clotting and clot lysis caused by streptokinase have been studied. All BC studied, except Fe2+, maintained the formation of fibrin clot followed by its lysis. In the presence of BC the coagulation part of the turbidimetry curve changed in a dose-dependen manner and was characterized by: (1) the decrease of the induction period which seems to be due to thrombin activation or accelerating fibrin self-association; (2) the elevation of the maximal optical density of the fibrin clot and the velocity of its achievement. The fibrinolytic part of the curve was characterized by the optical density downfall acceleration at low Co2+, Cd2+, Zn2+ and Ni2+ concentrations but marked delay of the process at BC higher concentrations. So, ions of Co2+, Cd2+, Zn2+ and Ni2+ but not Fe2+ significantly influence the dynamics of thrombin-induced clot formation and optical clot characteristics. At different ion concentrations BC may activate or inhibit fibrinolysis.

Cations, Divalent↗
PubMed1995

[Structure and properties of extracellular proteins regulating the proteolytic phase of complement activation].

The structure and biochemical properties of the major soluble regulatory proteins of the complement, including the CI-inhibitor, factors I, H, and J, properdin, the C4-binding protein and other protein components, are reviewed. Three types of the proteolytic complement cascade regulation by proteins are envisaged: the first one involves the inhibition of complement proteases, the second one is based on proteolytic degradation of complement activation products and the third one includes the regulation of stability of complement protein complexes. The main functional role of humoral regulatory proteins consists in the limitation of the proteolytic cascade.

Complement Activation↗
PubMed1993

[Concentration-functional interrelationships in the human alternative complement activation pathway].

The dependence of the rate of human complement mediated lysis of rabbit erythrocytes on concentrations of factors B and D of the alternative pathway is characterized by saturation kinetics. At low B and D concentrations no lysis occurs until certain "threshold" concentrations of the respective factor are reached. The type of dependence of the hemolysis rates on the C3 concentration is wavelike, i.e., at definite C3 concentrations the erythrocyte lysis is inhibited. It has been supposed that C3 not only mediates the complement-dependent hemolysis but also plays a prominent role in the self-regulation of this process.

Animals↗
PubMed1992

[Disorders of immunity in chest and abdominal injuries].

Under study were disturbances in the immune competent system in 245 patients with injuries of the chest and abdomen in dynamics of the early posttrauma period. Specific features of the disturbances were analyzed in the complicated and noncomplicated course of the trauma disease. The informative value and prognostic significance of certain indices are discussed as well as approaches to immune correction.

Abdominal Injuries↗
PubMed1988

[Pathogenetic substantiation of photomodification of autologous blood in the prevention and treatment of complications of closed chest trauma].

Three groups of patients with traumas of the chest were investigated: 1. 1533 patients treated by traditional methods: 2. 258 patients treated by transfusions of photo-modified blood; 3. 50 patients treated by autohemotransfusion. The authors have shown expediency of transfusions of photomodified autoblood. It decreased the amount of complications, lethality and improved biochemical parameters of blood.

Adolescent↗
PubMed1988

[Complications of closed chest injuries].

The role of predisposing factors in the development of complications in 1533 patients with closed traumas of the chest was studied as well as the dynamics of the state of the system of humoral regulation of microcirculation. The factors predisposing to the development of complications are the age older than 40, hospitalization later than 1 day from the trauma, double fractures of the ribs, injuries of lungs, hemothorax, concomitant diseases. In all the patients there was a subacute syndrome of disseminated intravascular coagulation, activation of the Kallikrein-Kinin system and inhibition of the complement system.

Adolescent↗
PubMedDate not supplied

[Eznzymatic conversions of ortho-nitrophenyl organophosphorus compounds in the tissues of white rats].

In homogenates of rat tissues hydrolysis of O-heptyl-O-orthonitrophenylmethyl phosphonate, O-pentyl-O-orthonitrophenylmethyl phosphonate and O-heptyl-O-isopentyl-O-orthonitrophenylphosphate was studied. Hydrolysis of the preparation was shown to be carried out mainly in liver tissue and slso in kidney and blood serum. The substances studied were cleaved only at the bond P-O-aryl. The structure of orthonitrophenyl phosphoorganic substances exhibited the distinct effect on Km and on the maximal rates of the enzymatic hydrolysis. In all the tisses studied O-heptyl-O-orthonitrophenylmethyl phosphonate was hydrolyzed with maximal rate.

Animals↗
PubMedDate not supplied

[Mechanism of acceleration of acid hemolysis of the E-form of serum albumin].

The influence of human and bovine serum albumin on the proton-mediated lysis of human, rabbit and sheep erythrocytes was studied. An essential acceleration of hemolysis (2-7-fold) by the action of albumin was observed only at pH values below 4.0, i.e. at values at which the transition of albumin to the E conformation occurs. It was shown in the experiments with fatty-acid-free albumin and the protein loaded by palmitate that the accelerating effect of albumin was due to the hemolytic action of fatty acids released from the protein. As a result of the proton potentiation of detergent-dependent hemolysis, fatty acids released from E-albumin become more potent hemolytic agents.

Acids↗
PubMedDate not supplied

[Modification of proteolytic complement cascade after treatment with exogenous heparin].

The influence of heparin therapeutic concentrations (0.25-10 U/ml) on the kinetic indices of human serum complement activity has been studied. An acceleration of complement-dependent lysis of rabbit erythrocytes via alternative complement pathway was found at low (0.25-0.5 U/ml) heparin concentrations and complement inhibition at higher (5-10 U/ml) concentration. The alternative pathway inhibition was revealed mainly by lag-period elongation of the hemolysis. Heparin in the concentrations more then 1 U/ml caused dose-dependent lowering of sheep erythrocytes hemolysis rate accompanied with reciprocal elevation of complement hemolytical capacity, which shows more "economical" consumption of complement components at heparin presence. The identical effect was observed in sera, deficient in factor D of alternative pathway of complement activation. This can be an evidence of the prevailing heparin inhibition of the classical pathway.

Animals↗
PubMedDate not supplied

[The action of karbogal on the complement system under model conditions and in an animal experiment].

The influence of dimethylperfluorocyclohexane (carbogal) on the hemolytic activity of human blood serum complement was studied in vitro. It has been show that different effects of carbogol on the complement depend on the serum lipid composition. Endotracheal administration of carbogal to rats results in a significant reduction of complement activity in the animal's blood. Significant changes in the hemolytic activity of the complement recorded 21 days after the endotracheal administration of the compound are, probably, associated with the complement depletion after its activation by carbogal particles or with disorders in the complement component synthesis by macrophages.

Animals↗
PubMedDate not supplied

[The mechanisms of fucoidan action on human complement].

The action of fucoidan (a sulfated polysaccharide) on human serum complement has been under study. Fucoidan inhibited the classical pathway of complement activation up to the complete arrest of the complement-dependent hemolysis achieved at the polysaccharide concentration higher than 200-250 mg per 1 ml of human serum. The classical pathway inhibition by fucoidan seems to be due to the binding to subcomponent C1q. In the alternative pathway, fucoidan also showed an inhibitory effect seen first in dose-dependent elongation of the lag-period preceding complement-dependent hemolysis. Experimental data suggest that fucoidan target is complement factor D, some part of the which (less than 30%) remains stable to the polysaccharide concentration as high as 600 mg/ml. The fucoidan properties described in this study can be used for cell protection against self-activated complement.

Animals↗
PubMedDate not supplied

[Structure and properties of the complement system proteinases].

Biochemical aspects of enzymes of the complement functioning are presented. Proteolytic, esterolytic and amidolytic characteristics of the complement components which are enzymes in their nature as well as the structure and properties of complex proteases of the activated complement are analyzed.

Amides↗
PubMedDate not supplied

[Activity of the complement system in blood serum of dogs after treatment of acute necrotic pancreatitis with boiled pancreatic juice].

The investigations were conducted on 14 dogs. To assess the blood serum complement system, the erythrocyte lytic rate of a rabbit (RE) and a sheep (SE), the hemolytic capacity of the complement system against rabbit (RH) and sheep (SH) was measured. In acute necrotic pancreatitis, no changes in SE and SH were revealed either in the control and experimental animals. RH was decreased both in the control and experimental animals. Lower RE was found only in the controls untreated with boiled pancreatic juice. It can be suggested that in the controls the decrease in the parameter RE that characterized the activity of the complement system is associated with the emergence of complement inhibitors, which did not take place when the boiled juice was given. Preventing the complement inhibitors from forming, pancreatic juice is likely to be able to diminish the body's endogenous intoxication which is a cause of death in acute necrotic pancreatitis. This may be suggested by the higher survival of the animals and lower relative extent of pancreatic acinar tissue necrosis after boiled pancreatic juice treatment of acute necrotic pancreatitis.

Animals↗
PubMedDate not supplied

[Membrane proteins as regulators of the complement system].

The data on structure, biochemical properties and functions of membrane proteins, performing cell defence against complement lysis, are summarized. Proteins DAE (decay accelerating factor) and CR1 (complement receptor of type 1) reduce the stability of complement convertases and cause their dissociation. MCP (membrane cofactor protein) and CR1 act as cofactors. In factor I mediated proteolysis of the convertase fragments C3b and C4b. The proteins C8bp-(C8-binding protein) and protectin affect membrane attack complex assembly. In contrast to MCP and CR1, which are integrative proteins, DAF, C8bp and protectin are bound to membranes with their glycophospholypid anchors. Tissue distribution of the proteins and the ways of their solubilization into biological fluids are reviewed.

Cell Membrane↗