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Medical records of 320 persons, who were injured in terrorist attacks in 1999-2003, were analyzed. The main errors in rendering the anesthetic-and-resuscitation care were pointed out. An algorithm of actions is elaborated for the anesthesiologist working at the reception, surgical and intensive care departments of a hospital. Owing to the mentioned algorithm, the lethality rate of wounded persons dropped from 18 to 10%.

A model of myosin complex with two active sites is considered. Each of the sites is supposed to pass through four states during a cycle of ATP hydrolysis. The model describes the distribution of the complex between states and the ATP hydrolysis rate as dependent on ATP concentration and reaction constants. Some of the constants were determined experimentally [6], but these values reproduce experimental curves [5] only with the assumption of cooperativity. If the first site is bind to actin, the rate of binding for the second one is shown to increase tenfold. If one of the sites is bind to actin by a "pulling" bridge, and the second site is in "rigor" state, then the ATP binding for the second site is about ten times faster. The transition into the rigor state proceeds much faster if both sites form pulling bridges. The rate of binding to actin is the same for one and for two sites.

A kinetic model of ionophore-induced oscillation of ion fluxes in mammalian erythrocytes is proposed. The model is based on the regulation by Ca2(+)-ions and calmodulin of (Ca2(+) + Mg2+)-dependent ATPase of erythrocytes. The results obtained are in a good agreement with the experimental data available.

Based on literature data, the main kinds of thrombocytopoiesis regulation are analyzed. It is shown that humoral factors regulate the intensity of proliferation of committed precursors and the mean sizes of mature megakaryocytes. The activity of these factors depends on the numbers of thrombocytes in blood and of megakaryocytes in bone marrow. The evidence presented in the review enables one to give a quantitative description of the relationship between the rate of thrombocytopoiesis and the content of thrombocytes in blood. The fact that the alteration of the time of megakaryocyte maturation does not depend on the duration and strength of the influences points to a non-specificity of this reaction. A scheme for the thrombopoiesis regulation is proposed which can serve as a basis for its mathematic description.

Analysis of the earlier obtained data on the effect of hydroxyurea on megakaryocytopoiesis by a simulation model has shown that differentiation of proliferating precursors of the megakaryocytes depends on their amount in bone marrow; the time of their involvement in the proliferating pool increases if the number of proliferating cells decreases. Within 24 h after the treatment with hydroxyurea (900 mg/kg), the transit time for the mouse megakaryocytes is reduced by about 14 h due to acceleration of the latest developmental stages. A hypothesis is put forward which accounts for correlation between the duration of proliferative period and the volume and maturation time of megakaryocytes.

The cells giving rise to colonies in the spleen of a lethally irradiated recipient after their transplantation (exogenous CFUs) have a higher self-maintaining ability than those that repopulate their own hemopoietic territory after irradiation, due to the migration of these cells from screened territories (endogenous CFUs). The number of exogenous CFUs and their self-maintaining ability do not change with animals ageing.

Ultrasound of 0,2 Wt/cm2 intensity affects the ionic transport across the mitochondrial membrane in vitro. In the presence of 1 mM EGTA in the incubation medium ultrasound slows down K+ exit into the external medium after the addition of an uncoupling agent (2,4-dinitrophenol). With the addition of 100 divided by 400 mM Ca2+ to the starting medium ultrasound makes the amount of Ca2+ absorbed by mitochondrial decrease and the rate of Ca2+/H+ electroneutral exchange increase. Without Ca2+ ultrasound does not influence the rate of coupled and 2,4-dinitrophenol uncoupled respiration and oxidative phosphorylation, i.e. does not produce strong functional changes.

In experiments with reaction centers (RC) preparations of Rps. sphaeroides, strain 1760-1, pH of the suspension medium was found to change under continuous light excitation. The concentration of hydrogen ions starts to decrease fastly (t1/2 = 2--4 s) after the light is on, whereupon it increases slowly, to a steady-state level, within t1/2 = 5--7 min. During the fast phase 0.3 microM H+/1 microM of RC are absorbed and 7--8 microM H+/1 microM of RC are released under the slow phase. The fast phase is suppressed by ortho-phenantroline (10 mM)--an inhibitor of electron transfer from the primary (Fe-quinone complex) to the secondary (quinone) electron acceptors. Glutaraldehyde which is known to modify a protein structure of the RC inhibits the slow phase. The obtained data suggest that fast light-induced pH changes are due to a H+ uptake by the secondary quinoid anion-radical products; slow pH changes are ascribed to structural changes within the RC complex, which lead to a pK shift and/or changes in the amount of dissociating groups on the protein interfacial surface. The conclusion was supported by an observation of light-induced changes in buffer capacity of an RC suspension and by a light-induced increase in the amount of SH-groups titrated by 5.5-dithio-bis(2 nitro)-benzoic acid. The role of conformational dynamics of photoactive pigment--protein complexes in the functions of the RC is discussed.

The role of cells capable of formation of megakaryocytic colonies (CFUm) in regulation of thrombocytopoiesis was studied using a simulation model of megakaryocytopoiesis. The CFUm were shown to be the least differentiated cells involved in regulation of megakaryocytopoiesis in mice upon immune thrombocytopenia and after intravenous injection of hydroxyurea. A correlation was found between the CFUm population productivity and the number of cells in a transit population of the megakaryocytic line which makes it possible to reproduce experimental kinetics in the model. The duration of cell development from CFUm to megakaryocytes is about 3 days.

A method of simulation has been proposed for studying megakaryocytopoiesis. A model has been developed which takes into account the age structure of cell population, the stochasticity of their maturation, and the principles of megakaryocytopoiesis regulation (known from the experiments). The mean number of divisions in a proliferating pool has been determined, as well as the duration of development of the cells with a positive acetylcholine esterase reaction.

Simulation experiments have shown that just after antiplatelet serum of rabbit blood is introduced into mice the transit time of early proliferating precursors of the megakaryocytes is reduced by about 17 h, the transit time for megakaryoblasts increases, and within 24 h after the treatment the transit time for mature megakaryocytes is reduced b about 17 h. The data obtained confirmed our earlier hypothesis on correlation between the duration of proliferative period and the mean size of megakaryocytes.

Mathematical modelling used in analysing the postirradiation changes in megakaryocytopoiesis permitted to determine the level of radiation-induced injury in each experiment conducted and to show that megakaryocytopoiesis regulation followed the same mechanism after irradiation as it does normally and after the effect of hydroxyurea and anti-thrombocyte serum. The analysis has demonstrated that after the stem cell death induced by ionizing radiation, the regeneration can be provided by the committed cells, and the level of regeneration is determined by the maturity of precursors.

From the comparison of the results of model and experimental kinetics of thrombocytopoiesis the following parameters have been quantitatively estimated: (1) the percentage of cells killed during the interphase (interphase death) and (2) the duration of the mitosis delay and the abortive rise. There was a 1.3-1.5-fold and 2-3-fold nonspecific and postirradiation, respectively, decrease in the megacaryocyte maturation time. The transit time of the committed megacaryocyte precursors was reduced due to death of premature precursors and survival of mature forms.

A study was made of the kinetics of thrombocytopoiesis restoration in lethally irradiated mice after transplantation to them of the donor marrow cells. In the initial period, the thrombocytopoiesis restoration is provided by transite cells-precursors of megakaryocytes present in the transplanted bone marrow; the subsequent restoration is due to cells of the self-maintaining population. The level of restoration does not correlate with the number of polypotent cells that form macrocolonies in the spleen of irradiated recipients.

A mathematical model of thrombocytopoiesis is proposed which accounts for the recent data on its regulation. It is shown that the compensatory response of the system to a decrease in the level of thrombocytes in the blood is controlled by the total amount of thrombocytes and megakaryocytes. The proliferation intensity of megakaryocytes and the total number of thrombocytes reveal, respectively, a lineary and a logarithmical dependence on the total number of thrombocytes and megakaryocytes. The limits of the post-transfusion level of thrombocytes are defined, within which the thrombocytopoiesis is controlled only by the number of thrombocytes. The values of parameters characterizing the behaviour of the thrombocytopoiesis system are calculated.