Objective: It is known that local or systemic injection of hemostatic drugs is used to reduce blood loss and number of blood transfusions in patients with hypocoagulation and hemorrhagic diathesis. However, the analysis of literature data shows that the drugs applied for the control of bleeding, traditionally used in medical practice, are not effective enough. This study deals with the systemic hemostatic activity of bis (2-aminoethan-1- sulfonate) calcium in the experiment.Methods: Experimental work in vitro is performed on the blood of healthy male donors, under conditions in vivo it is done on intraperitoneal injection in male rats. Thromboelastography was carried out with apparatus Thromboelastography (TEG) 5000 (Haemoscope Corporation, United States). The influence of first synthesized derivative and ethamsylate on functional activity of platelets was studied using a platelet aggregation analyzer “Biola 230LA” (Russia). Experimental evaluation of the system specific hemostatic activity in vivo was carried out using the model of parenchymatous bleeding in mature male rats. The interference came amid registration of bleeding stop time and extent of blood loss.Results: Bis (2-aminoethan-1-sulfonate) calcium shows procoagulation and proaggregant activity both in vitro and in vivo. Proaggregatory effect of bis (2-aminoethan-1-sulfonate) calcium is successfully implemented in the systemic hemostatic activity in terms of parenchymal bleeding, surpassing the control group and the group of etamsylate.Conclusion: The results of these studies reveal potentially high systemic hemostatic activity of bis (2-aminoethan-1-sulfonate) calcium, urging the need for further study on this compound and its analogs to create on their basis highly efficient, selective correctors of the hemostatic system.
Although the total content of organic s compounds in water is regulated, it is rather difficult to formulate and set standards for individual organic substances coming to the biological treatment facilities of urban aeration stations. Many experts believe it necessary to conduct further experimental studies to set their permissible concentrations and prevent slowing down biological treatment. One of the accepted experimental control methods for toxicity is a bio testing method. In the course of the present study, an investigation into ampicillin toxicity was performed for the test-objects daphnia and community of microorganisms in active silt. The experiment was carried out on crustaceans using N.S. Stroganov standard technique. The impact of antibiotics on active silt was assessed by changes in the microorganisms’ dehydrogenases activity. The research results allow to characterize ampicillin as very low toxic to Daphnia and to active silt community of microorganisms , toxic effect of the antibiotics was established in concentrations of 200 to 400 mg/l.
Changes in the peptide composition of hemolymph of Galleria mellonella larvae induced by their immunization have been studied, and some new peptides have been found. The composition of fractions exhibiting antibacterial activity was investigated. Known antibacterial peptides have been found in the hemolymph of control larvae and those immunized with bacteria.
Due to the continuous reduction of the areas for crops and increase of urbanpopulation, the increase in productivity of crops is especially importantaspect in production of food today. One of problems of agriculture is creationof conditions for receiving a crop. Quality of a crop of various crops depends onefficiency of preseeding processing of seeds. This research investigated a methodof impact of preseeding processing of seeds of flax by a complex of physicalfactors: ultra-violet radiation, ozone and the magnetic field (MF) with induktionof 100, 200, 250 and 300 Gs on growth and activity of a catalase andperoxidase of a plant, and also the maintenance of photosynthetic pigments inflax sprouts.
The fractions containing antimicrobic peptides have been purified from a haemolymph of caterpillars Galleria mellonella by chromatographic methods and studied by mass spectrometry.
In the course of previous experiments, a technique was developed for the preparation of a copolymer of styrene and α-methylstyrene. This technique is an emulsion polymerization in the initiator of ammonium persulfate in an inert zone of direct current argon. It was found that the best emulsifier is potassium stearate. This substance can be explained by those copolymers that showed the best dielectric performance. In the course of the new experiment, a series of new copolymers of 4-methylstyrene-α-methylstyrene and 4-methoxystyrene-α-methyl-styrene was obtained in the molar ratios of the initial monomers of 8 : 3, 9 : 2 and 10 : 1 for both rows of copolymers. The outputs of the pure product for all compounds accounted for more than 60% in terms of the initial monomers. To further measure the value of the specific volume resistance of the material, films of each newly synthesized copolymer were obtained. Samples of the copolymers were dissolved in methylene chloride and applied to a smooth glass substrate. The choice of this solvent is due to its low toxicity and low boiling point. For the experiment were selected samples with a film thickness of 50 microns. Measurements of the specific volume resistance were carried out at the Research Institute "Girikond" (St. Petersburg) using an Agilent 4339B instrument. The operating voltage was 100 V. The measurement results showed that samples of 4-methoxystyrene-α-methylstyrene copolymer were several orders of magnitude superior to samples of 4-methylstyrene-α-methylstyrene copolymer. Most likely in this case such a difference in the indices of the specific volume resistance of the copolymer films is due to the nature of the functional groups of substituents in the copolymer. From the obtained measurement results it can be seen that the samples containing the methoxy group have a high resistance value compared to the samples containing a methyl group in their structure. In a series of samples of copolymer films, an increase in the specific volume resistivity index is observed with a decrease in the α-methylstyrene content in the copolymer structure. This dependence is observed for copolymers of 4-methylstyrene-α-methylstyrene and for 4-methoxystyrene-α-methylstyrene. The sample of 4-methoxystyrene-α-methylstyrene with a molar ratio of initial monomers of 10 : 1 has the highest value of specific volume resistance among all the obtained samples of copolymer films.
Two new copolymers of 4-methylstyrene and α-methylstyrene were obtained by the emulsion polymerization method according to the previously described and tested method in the course of the experiment in laboratory conditions. The molar ratio of the starting monomers of 4-methylstyrene and α-methylstyrene was 9: 2 and 10: 1, respectively, in each material sample. The structure of the copolymers obtained was confirmed by IR and 1H NMR spectroscopy. Under laboratory conditions, three prototypes of each copolymer film were obtained from the solution. A sample of the copolymer was dissolved in methylene chloride was applied on a smooth glass substrate. After complete evaporation of the solvent, the film was separated from the substrate. The thickness of the films for each copolymer sample was 20, 30, and 50 microns. In the course of further experimentation, these samples were examined for the values of dielectric constant and tangent of dielectric loss angle. The basis of this experiment used a resonant method of measurement. The presented method is based on the variation of conductivity due to a change in the electrical capacitance of the oscillating circuit. In this experiment, the magnitude of the electrical capacitance and the tangent of the dielectric loss angle were measured. Based on the value of the capacitance and the parameters of the film sample to be measured, it is possible to calculate the dielectric constant. From the data obtained it can be seen that with increasing film thickness, dielectric constant values decrease. However, the indicators of the tangent of dielectric loss angle increase. With an increase in the measurement frequency, a slight decrease in the dielectric constant is observed, and the value of the tangent of the dielectric loss angle decreases nonlinearly. In addition, it should be noted that the samples of 4-methylstyrene-α-methylstyrene copolymer films with a molar ratio of starting monomers of 10: 1 have a higher dielectric constant, along with lower values of the dielectric loss tangent. From this it follows that samples with a lower proportion of α-methylstyrene in their structure have better dielectric characteristics compared with their counterparts with a high content of α-methylstyrene.
At the first stages of the research work, a copolymer of styrene and α methyl styrene was synthesized by the method of radical emulsion polymerization in an inert atmosphere of argon. The initiator was ammonium persulfate. The molar ratio of the initial monomers of styrene and α-methylstyrene was 70 : 30, respectively. It was found that copolymers synthesized under special controlled conditions have good values of permittivity and dielectric loss tangent. It should be noted that the choice of emulsifier directly affects the values of these indicators. It was previously shown that the most optimal emulsifier is potassium stearate, using which the best values of the dielectric constant and dielectric loss tangent were achieved. At the second stage of the research work, a number of copolymers were synthesized containing 4-methoxystyrene, 4 methyl styrene and α-methyl styrene in their structure. It was experimentally confirmed that the synthesis procedure may be applicable for the preparation of copolymers based on derivatives of styrene and α-methylstyrene. The resulting series of copolymers is highly soluble in methylene chloride; films of each copolymer sample of different thicknesses were obtained by casting from a solution. For this series of copolymer films, the dielectric constant and dielectric loss tangent were determined. It was found that the best values of permittivity and dielectric loss tangent are possessed by a sample of copolymer 4-methoxystyrene and α-methylstyrene. At the latest stage of the study, copolymers of styrene and 2,3,4,5,6-pentafluorostyrene, α-methylstyrene and 4-fluoro-α-methylstyrene, 2,3,4,5,6-pentafluorostyrene and 4-fluoro-α-methylstyrene were synthesized. These fluorine-containing derivatives of styrene and α-methylstyrene easily enough enter into the reaction of radical emulsion copolymerization. The copolymer yields are 53-76%, calculated on the weight of the starting monomers. The structure of a number of newly synthesized copolymers was confirmed by IR spectroscopy. In the future, it is planned to define the values of dielectric constant and dielectric loss tangent for these copolymer samples. It is planned to study the thermomechanical properties of the samples, since fluorine-containing polymers are a promising material for operation at elevated temperatures.
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