[Covalent stretokinase-polyethylene glycol conjugates with increased stability and decreased side effects]

By variation of incubation time of streptokinase (SK) with activated polyethylene glycol (M 2 and 5 kDa, PEG2 and PEG5) it was obtained covalent SK-PEG2 and SK-PEG5 conjugates with different modification degrees of amino groups of protein and their properties were studied in vitro as compared with free SK. It was shown, that maximal stable and retaining 80% fibrinolytic activity SK-PEG2 and SK-PEG5 conjugates are formed when the modification degrees of amino groups of protein are 54 and 52%, respectively. At interaction of the given conjugates with equimolar plasminogen concentration it were formed the plasmin (Pm)·SK-PEG2 and Pm·SK-PEG5 activator complexes, the maximal amidase activity of which is equal to activity of unmodified Pm·SK complex. It was found, that the catalytic efficiency of plasminogen activation (kPg/KPg) by Pm·SK-PEG2 complex is some higher (2.84 min(-1) μM(-1)) and by Pm·SK-PEG5 complex is lower (1.17 min(-1) μM(-1)), than that by unmodified Pm·SK complex (2.1 min(-1) μM(-1)). Investigation of lysis kinetics of human plasma clots and depletion of plasminogen and fibrinogen in plasma under the action of free SK and SK-PEG2 and SK-PEG5 conjugates showed, that the latter's have high thrombolytic activity (89 and 72%, respectively) and cause 3.5-4 fold lower side effects, than free SK. Obtained by us SK-PEG2 and SK-PEG5 conjugates with increased stability and decreased side effects may be used in the therapy of thrombotic disorders.

[Polysuccinimide exhibited antitumor activity in the experiment]

Antitumor activity of the novel for oncology compound, such as polysuccinimide, against some of experimental tumor models (Lewis lung carcinoma, Acatol adenocarcinoma, Ca-755 adenocarcinoma) has been established. This drug induced 60-80% tumor growth inhibition of these murine solid tumor strains. Polysuccinimide is also effective (60%) against development of metastatic process in lung (Lewis lung carcinoma). Polysuccinimide causes no changes in pH level in tumor tissue (P-388 leukemia, Acatol adenocarcinoma). This agent may be recommended for further profound preclinical study.

[Polymorphism of the plasminogen activator inhibitor type 1 gene, plasminogen level and thrombosis in patients with antiphospholipid syndrome]

The frequency of venous and arterial thromboses and plasminogen level were investigated in 78 patients with antiphospholipid syndrome (APS), 35 of whom with systemic lupus erythematosus (SLE+APS) and 43 - with primary APS (PAPS). The levels and genotype of plasminogen activator inhibitor type 1 (PAI-1) were determined in 45 patients with APS, of whom 21 patients with SLE + APS and 24 patients with PAPS. A control group included 10 healthy individuals without autoimmune disease signs and thromboses on period of investigation and in past history. It was shown for the first time that for one third of 67 patients with APS and thromboses high positive levels of antiphospholipid antibodies (aPL) are associated with low plasminogen levels. The levels of PAI-1 antigen measured by ELIZA method, which detects active, latent and bound with plasminogen activator PAI-1, were opposed with frequency of thromboses in APS patients. Correlation between the high and increased levels of PAI-1 and high positive aPL levels was found for one third of 43 patients with APS and thrombosis. One of the possible mechanisms of this interconnection was considered. It was shown that arterial and, to a more extent, venous thromboses are associated with the 4G/5G polymorphism of PAI-1 gene and high plasma level of the inhibitor in 79% of APS patients. At the presence of the 4G allele patients with SLE+APS had higher PAI-1 levels than patients with PAPS. The obtained results show that measuring the levels of plasminogen and PAI-1 as well as the 4G/5G polymorphism of PAI-1 gene which is associated with thromboses may have the practical significance for identification of high risk of thrombosis in APS patients.

Production of biofuels from pretreated microalgae biomass by anaerobic fermentation with immobilized Clostridium acetobutylicum cells

The purpose of this work was to study the possible use of pretreated biomass of various microalgae and cyanobacteria as substrates for acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum cells immobilized into poly(vinyl alcohol) cryogel. To this end, the biochemical composition of photosynthetic microorganisms cultivated under various conditions was studied. The most efficient technique for pretreating microalgal biomass for its subsequent conversion into biofuels appeared to be thermal decomposition at 108 °C. For the first time the maximum productivity of the ABE fermentation in terms of hydrogen (8.5 mmol/L medium/day) was obtained using pretreated biomass of Nannochloropsis sp. Maximum yields of butanol and ethanol were observed with Arthrospira platensis biomass used as the substrate. Immobilized Clostridium cells were demonstrated to be suitable for multiple reuses (for a minimum of five cycles) in ABE fermentation for producing biofuels from pretreated microalgal biomass.

[Modern aspects of diabetic ketoacidosis treatment in children]

The aim of the research - the analysis of the regularities of diabetic ketoacidosis treatment in children and adolescents with type 1 diabetes mellitus, the explanation of the results obtained with the use of biological systems stability theory elements. MATHERIALS AND METHODS: The study included 90 children with type I diabetes mellitus in a state of diabetic ketoacidosis of different severity degree. With newly diagnosed type 1 diabetes mellitus - 56 children, with the "courced" diabetes - 34 children. In the evaluation of patients status was defined glucose, pH, and other indicators of acid-base status, using gas analyzer GEM Premier 3000 ("Instrumental laboratory", USA).

RESULTS

All children received treatment under the Protocol, approved by the Moscow Health Department, withdrawn from the state of diabetic ketoacidosis without any complications. In the basis of this methodology is application of glucose solutions and "small" doses of insulin from the start of infusion therapy in spite of hyperglycemia. This therapy helps to prevent cerebral edema against the background of gradually reduce the blood glucose. pH recovery was explained by the existence of a common pathophysiology process. Given the qualitative description of this process on the basis of biological systems stability theory. Were determined 3 stationary state: pH = 7.4 and pH < 6,9; and one is unstable, called "the point of no return" - pH = 6.9. The conclusions of this theory substantiate the effectiveness of ketoacidosis treatment with offered method

CONCLUSION

The offered technique for diabetic ketoacidosis treatment on the basis of the glucose solutions infusion throughout the treatment and "small" doses of insulin values pH and glucose in a safe range, even in patients with high risk of brain edema, which is confirmed by biological systems stability theory.

[Exogenic proteins in the human exhaled breath condensate]

The analysis of the protein composition of exhaled breath to diagnose diseases of the respiratory system raises a problem of differentiation proteins of expressed in the tissues of the lungs and respiratory tract (endogenous) and got in the respiratory system from the ambient air in the process of respiration (exogenous). In this work an attempt was made to estimate a set of exhaled exogenic proteins by mass spectrometry coupled with nanoflow HPLC. Six-month isolation of healthy donors indoors with air cleaned of dust leads to removal from the spectrum of exhaled proteins of some keratins that are considered therefore to be exogenic. Non-keratin proteins may also circulate between the ambient air and human respiratory ways, but their concentration appears to be significantly lower the keratin concentrations (especially epidermis keratin). Among non-keratins dermcidin seems to be the most significant exogenic protein of exhaled air. The conclusion of the diagnostic value of exhaled proteins can be done only after careful comparison of the results of quantitative and qualitative analysis of their composition in norm and pathology for a statistically significant sample of donors.