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In this paper, the fuzzy model of functioning of shared educational-laboratory and production capacities on the example of a cluster in the information security field is developed. The proposed model helps to conduct an integrated accounting of quality factors, given their uncertainty (the results of equipment operation, the results of compliance with regulatory and technical documentation, the results of research work, the results of repairing the equipment, the results of the final state certification of students). This approach allows accurate assessing the functioning of shared educational-laboratory and production capacities to make reliable decisions on the management of educational clusters in the information security field.

We study the concentration of stresses due to two boundary defects located in an elastic half-space with stress-free boundary loaded at infinity with a constant shear load. The problem is reduced to solving singular integral equations for the cases in which the half-space contains defects of different types: two cracks, two inclusions, and a crack and an inclusion, whose solutions are sought by the method of mechanical quadratures. The interaction of the defects as they approach each other and the influence of their relative sizes are studied numerically.

Group A streptococcus polysaccharide is found to inhibit the activity of ConA-stimulated T suppressors. A-variant streptococcus polysaccharide, representing an L-rhamnose homopolymer which is identical to the rhamnose carcass of group A streptococcus polysaccharide, does not possess such an effect. The effect of group A streptococcus polysaccharide on the activity of T suppressors is considered to be associated with its determinant including N-acetylglucosamine as an obligatory component.

The influence of group A streptococcal polysaccharide (A-PS) on the proliferation and functional activity of subpopulations CD4+ and CD8+ of human peripheral blood lymphocytes has been studied. As revealed in this study, A-PS, though having no mitogenic activity of its own, is capable of influencing the process of proliferation of two main T-cell subpopulations in the presence of PHA. Its action has a regulatory character and is manifested by the maintenance of the ration of lymphocytes CD4+ and CD8+ in the culture at a constant level (approximating 1). This effect is seemingly linked with changes in the functional activity of lymphocytes in both subpopulation CD4+ and subpopulation CD8+. The detected properties of A-PS make it possible to regard it as a pathogenic factor playing an important role in immunoregulatory disturbances in diseases connected with infection caused by group A streptococcus.

It was found that group A streptococcal polysaccharide (A-PS) had no mitogenic effect on the intact human blood mononuclear cells' culture (MNC) and on its proliferation stimulated with ConA. Using a double staining technique for simultaneously determining cell surface phenotype and degree of cell activation by it's ability to include the tetrazolium dye MTT (3-[4,5-dimethylthiazol-2-yl] -2,5-diphenyl tetrazolium bromide) it was established that A-PS decreased the percent of activated (MTT+) cells in the subpopulation of CD8+ and increased the percent of MTT+ cells among CD4+ lymphocytes in the intact MNC. In the MNC stimulated with ConA A-PS caused only one of these effects: it decreased the percent of MTT+ cells in the subpopulation of CD8+ lymphocytes. The correlation was established between the results obtained with MTT-technique and cell transfer test, because the MNC preincubated with ConA and A-PS lost the ability to suppresses MNC proliferation stimulated with PHA. The data obtained supported the assumption that A-PS as a carrier of determinants common with thymus epidermal antigens (factors) may act as it's functional analogue and thus promote the development of autoimmune process during the rheumatic fever.

The ability of a thermostable and acid-stable serine protease inhibitor from rabbit blood serum (TASPI) to inhibit the transformation of human peripheral blood lymphocytes stimulated by phytohemagglutinin (PHA) or concanavalin A (con A) was demonstrated. The degree of inhibition depends on the concentration of the inhibitor and its specific activity. The maximal degree of inhibition was 50–70%. TASPI has no cytotoxicity. Stronger inhibition of transformation is observed if TASPI is added to the culture 24 h after the addition of PHA. Data on the antiprotease activity of human blood serum, either native or inactivated under different conditions, are given. The results suggest that TASPI participates in the control of the biological activity of lymphoid tissue cells.

Monovalent and bivalent Fab fragments from normal human and rabbit γ-globulins were shown to suppress blast transformation of human lymphocytes induced by phytohemagglutinin and concanavalin A. The pepsin F(ab')2 fragments obtained from highly purified rabbit antidinitrophenyl antibodies possess similar properties. An inhibitory action of the fragments was observed when they were added to the culture both simultaneously with and 24 and 48 h after the mitogen. The results may mean that suppression of lymphocyte transformation by fragments of γ-globulins is not due to their composition with the mitogens for receptors on the target cells; activity of the Fab fragment is evidently determined by structures located outside the combining site of the antibody.

Preliminary incubation of lymphocytes in a leukocyte suspension or isolated in a Verografin-Ficoll gradient at 37°C leads to more intensive blast transformation in response to stimulation by phytohemagglutinin (PHA). Preincubation in the presence of soy trypsin inhibitor (500 μg/ml) abolishes this effect. The results suggest that neutral proteinases of neutrophils or monocytes participate in modification of the response to PHA.

A study was made of the sensitivity to prednisolone (PS) of peripheral blood mononuclear cells (MS) of patients with systemic lupus erythematosus (SLE) with renal lesion showing resistance to glucocorticoids (GC). It was shown that in most of the patients (60%) MC were poorly inhibited by PS whereas the rest of the patients (40%) demonstrated in vitro sensitivity compared to that of the donors and even higher in some cases. Thus, the group of SLE patients showing clinical resistance to GC action was inhomogeneous in sensitivity of their MC to PS; only some patients showed resistance associated with the properties of the MC system. Hemocarboperfusion was shown to produce a considerable effect on MC sensitivity to PS: higher sensitivity was noted in all the cases, it was particularly noticeable in the group of patients with low basal sensitivity to PS. An analysis of the data obtained led to a conclusion that hemocarboperfusion raised MC sensitivity to PS. This mechanism was shown to determine the efficacy of the method of therapy of resistance to GC.

Preincubation of lymphocytes in leukocytic suspension or those separated on verografin-Ficoll gradient at 37 degrees C leads to enhancement of blast transformation in response to phytohemagglutinin (PHA) stimulation. This effect is reversed by preincubation in the presence of soybean trypsin inhibitor (500 micrograms/ml). The results obtained suggest the participation of neutral proteinases from neutrophils or monocytes in the modification of PHA response.

The effect of neutral SH-dependent proteinase of the spleen on transformation of human peripheral blood lymphocytes has been studied. Proteinase (1--10 micrograms/ml) inhibits phytohemagglutinin-stimulated (PHA) lymphocyte transformation and has no effect on spontaneous transformation. Proteinase does not alter the mitogenic properties of PHA and possesses no cytotoxicity. Therefore, inhibition of stimulated lymphocyte transformation is either resultant of proteinase direct action on the cell or associated with the inhibitor factor formation.

Monovalent and bivalent Fab-fragments of normal human or rabbit gamma-globulin suppressed blasttransformation of human lymphocytes induced by phytohemagglutinin and concanavalin A. Peptic F(ab)2-fragments from highly-purified rabbit anti-DNP antibody displayed suppressing activity similar to that of the fragments of normal gamma-globulin. Fab-fragments affected blasttransformation when added to lymphocytes either simultaneously with the PHA or 24 and 48h after the mitogen. The data obtained may indicate that the inhibiting of lymphocyte blasttransformation produced by the gamma-globulin fragments was not caused by their competing with mitogens for the receptors on the target-cell; the Fab-fragment activity was probably determined by the structures located outside the antibody active centre.

Thermo- and acid-stable serine proteases inhibitor from the rabbit blood serum (TASPI) was shown to inhibit the human peripheral blood lymphocytes transformation stimulated by phytohemagglutinin (PHA) or concanavalin A. The extent of inhibition depended on the concentration of the preparation and its specific activity. The maximal inhibition of lymphocytes proliferation constituted 50 to 70%. TASPI displayed no cytotoxic activity. Considerably more effective inhibition was demonstrated by TASPI addition to the culture medium 24 hours after the addition of PHA. The antiprotease activity of crude human serum and that inactivated under different conditions is described. The results obtained suggest the participation of TASPI in the control of biological activity of the lymphoid tissue cells.