Fractionation of Vipera berus berus Snake Venom and Detection of Bioactive Compounds Targeted to Blood Coagulation System

Introduction. The performed research focused on a search for new biologically active compounds acting on blood coagulation system proteins and cells. To achieve this goal, we fractionated Vipera berus berus snake venom and studied the action of the separated fractions on human blood plasma, fibrinogen, platelets or red cells. Methods. Crude venom was fractionated using ion-exchange chromatography. Protein composition of fractions was studied using SDS-PAGE. The ability of fractions to prolong or initiate blood plasma clotting was studied using the prothrombin time test with thromboplastin. Fibrinogen-specific proteases were detected using enzyme-electrophoresis. Action on red cells was estimated using the hemolysis test. Aggregometry was used for the detection of action on platelets. All experiments in this study were performed in vitro. Results. We obtained fractions containing phospholipase and a protease that is able to hydrolyze fibrinogen, leading to the loss of its ability to polymerize and to maintain platelet aggregation. Conclusion. Further purification and study of these components can be a promising research direction for biotechnological as well as for biomedical use

Phenomenological description of the nonlocal magnetization relaxation in magnonics, spintronics, and domain-wall dynamics

A phenomenological equation called Landau-Lifshitz-Baryakhtar (LLBar) equation, which could be viewed as the combination of Landau-Lifshitz (LL) equation and an extra "exchange damping" term, was derived by Baryakhtar using Onsager's relations. We interpret the origin of this "exchange damping" as nonlocal damping by linking it to the spin current pumping. The LLBar equation is investigated numerically and analytically for the spin wave decay and domain wall motion. Our results show that the lifetime and propagation length of short-wavelength magnons in the presence of nonlocal damping could be much smaller than those given by LL equation. Furthermore, we find that both the domain wall mobility and the Walker breakdown field are strongly influenced by the nonlocal damping.Comment: 10 pages, 6 figure

Network Planning at the Faculties of Physical Education and Sport in the Postmodern Era

The article aims to study the issues of university teachers and students from the faculties of physical education and sport to improve the educational process based on the principles of network planning. The article presents the results of the sociological questioning of the subjects of the educational process of physical education and sport faculties about the problems in the organization and planning of effective learning, as well as appropriate optimizing recommendations. A subject correlation matrix has been developed in the furtherance of this goal, in which each subject has a specific line and column. The analysis of the subjects’ matrix allows one to pre-determine the order of study of individual subjects in courses and cycles, their relationship and interframe sequence. Within the framework of the experiment, the authors of the article have surveyed 52 university teachers and 450 physical education students. The survey included questions relating to personal opinions about the advantages and disadvantages of the new curriculum and relevant programmes in 16 major subjects. Statistical data processing was carried out using the SPSS Statistics 17.0 software package. The recommended concentrated arrangement of the leading subjects of the biomedical cycle will allow one to create an interdisciplinary programme giving a complete vision of the structure, functions and biochemical processes occurring in various human body systems.</p

Antiplatelet and antiproliferative action of disintegrin from Echis multisquamatis snake venom

Aim To purify the platelet aggregation inhibitor from Echis multisquamatis snake venom (PAIEM) and characterize its effect on platelet aggregation and HeLa cell proliferation. Methods Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix assisted laser desorption/ ionization time-of-flight (MALDI-TOF) were used for PAIEM identification. Platelet aggregation in the presence of PAIEM was studied on aggregometer Solar-AP2110. The changes of shape and granularity of platelets in the presence of PAIEM were studied on flow cytometer COULTER EPICS XL, and degranulation of platelets was estimated using spectrofluorimetry. Indirect enzyme-linked immunosorbent assay was used for the determination of target of PAIEM on platelet surface. An assay based on 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide was used to evaluate the effect of PAIEM on the proliferation of HeLa cells in cell culture. Results The molecular weight of the protein purified from Echis multisquamatis venom was 14.9 kDa. Half-maximal inhibitory concentration (IC50) of PAIEM needed to inhibit adenosine diphosphate (ADP)-induced platelet aggregation was 7 μM. PAIEM did not affect thrombin- or ADP-induced platelet activation, but it did prevent binding of the anti- IIb antibody to glycoprotein IIb/IIIa (GPIIbIIIa)-receptor of adhered platelets and inhibited the viability of HeLa cells by 54%. Conclusion As a member of the disintegrin family, PAIEM inhibited platelet aggregation and cell proliferation possibly by blocking integrin-mediated interactions. However, it did not impair cellular signaling causing any changes in platelet shape and granularity and did not affect ADP-induced platelet degranulation. This disintegrin was shown to be a potent inhibitor of integrin-mediated cellular interactions including platelet aggregation or cancer cell proliferation

Non-enzymatic activation of prothrombin induced by interaction with fibrin β26-42 region

We have discovered that addition of monomeric desAB fibrin to prothrombin leads to appearance of the thrombin-like activity of prothrombin towards S2238 chromogenic substrate. DesA and desABβ(15-42)2 fibrin forms did not cause any activation of prothrombin. From this observation we could suggested that amino acid residues of the 15-42 fragment of BβN-domain presented in desAB fibrin, cleaved in desABβ(15-42)2 fibrin and protected in desA fibrin, play a crucial role in the non-enzymatic activation of prothrombin. To identify the Bβ amino acid residues involved in the fibrin-prothrombin binding we used monoclonal antibodies 1-5G and 2d2a with epitopes in Bβ26-42 and Bβ12-26 fibrin fragments respectively. The thrombin-like activity in the mixture of prothrombin and desAB fibrin was monitored in the presence of each of these monoclonal antibodies. It was found that anti-Bβ12-26 antibody does not exhibit any inhibitory effect on the thombin-like activity of the mixture. In contrast, adding of Bβ26-42 antibody into the mixture of desAB fibrin with prothrombin diminished the thrombin-like activity by 70%. Recombinant dimeric peptides Bβ(15-44)2 and Bβ(15-66)2 that mimic amino acid residues in fibrin were also tested for their ability to activate prothrombin. It was found that both peptides were able to induce non-enzymatic activation of prothrombin. The activation was more evident in the case of Bβ(15-44)2 peptide. From the data obtained we can conclude that desAB fibrin binds to prothrombin through the Bβ26-42 amino acid residues and the formation of such a complex caused a non-enzymatic activation of prothrombin