[Duration of Dual Antiplatelet Therapy in Patients With Ischemic Heart Disease After Implantation of Endovascular Stents].

Optimal duration of dual antiplatelet therapy (DAPT) after stent implantation is uncertain. Some patients have an extended risk of thrombotic complications including that of very late stent thrombosis after cessation of recommended course of DAPT (6-12 months). On the other hand, there is a real risk of bleeding on DAPT.

[Antioxidant and antiaggregant effects of covalent bienzyme superoxide dismutase-chondroitin sulfate-catalase conjugate in platelet interactions].

A covalent bienzyme superoxide dismutase-chondroitin sulfate-catalase conjugate (SOD-CHS-CAT) demonstrated the dose-dependent inhibitory action on induced aggregation of platelets in the presence of hydrogen peroxide. Antioxidant activity of SOD-CHS-CAT appeared at much lower doses than for other CAT derivatives. We detected the antiaggregation effect of SOD-CHS-CAT for platelet aggregation induced by ADP, serotonin, TRAP (with their different mechanism of action).

Effect of hydrogen peroxide and catalase derivatives on functional activity of platelets.

Effects of H(2)O(2) on platelet aggregation were estimated in vitro in the presence and absence of inductors (ADP, serotonin, TRAP) and native and modified catalase. Dose-dependent effect of H(2)O(2) (50 μM or more) was investigated in a pathophysiological concentration of 300 μM inducing platelet aggregation. H(2)O(2) modulated aggregation induced by ADP, serotonin, and TRAP significantly increasing the initial platelet aggregation followed by disaggregation, which was always more pronounced than in control.

Biopharmacology of enzyme conjugates: vasoprotective activity of supramolecular superoxide dismutase-chondroitin sulfate-catalase derivative.

Bienzyme conjugate was obtained by the covalent connection of superoxide dismutase with catalase through endothelial glycocalyx glycosaminoglycan - chondroitin sulfate (SOD-CHS-CAT). This SOD-CHS-CAT conjugate has vasoprotective activity in respect to platelet interactions, tonus of the ring arterial fragment of a rat blood vessel, as well as normalization of hemodynamic parameters in rats and rabbits in conditions of oxidative stress caused by the administration of hydrogen peroxide. The SOD-CHS-CAT conjugate had antiplatelet potential due to its antiaggregation action manifested through the combination of enzyme activities and an acquired supramolecular structure.

[Disturbances of primary hemostasis in patients with dilation cardiomyopathy].

We studied morphological characteristics of platelets and parameters of platelet aggregation in patients with dilation cardiomyopathy. Augmented aggregatory activity of platelets was found in 76% of patients. In blood of majority of patients we found circulating leukocyte-platelet aggregates.