Mathematical approach to modeling of the treatment of suppurative processes

Consideration of an inflammation focus as an "open system" provided analogy between microbiological processes in inflamed wounds and in systems of continuous cultivation of microorganisms. Mathematical modeling of such systems is widely used. Some of the methods for the mathematical modeling were applied to chemoprophylaxis and chemotherapy of postoperative wounds. In modeling continuous cultivation of microorganisms it is usually necessary to determine optimal conditions for the maximum yield of their biomass. In modeling of wound treatment the aim was to determine the process parameters providing the minimum biomass. The described simple models showed that there could be certain optimal flow rate of the washing fluid in the aspiration-washing procedure for wound treatment at which the drug was not completely washed out while the growth rate of the microbial population was minimal. Such mathematical models were shown valuable in optimizing the use of bactericidal and bacteriostatic antibiotics.     

Etiotropic antibiotic therapy and immunotherapy of patients with pyo-inflammatory processes]

A 3-year experience was reviewed in the treatment of patients with pyoinflammatory processes (PIP) which developed during the postoperative period in 387 persons with closed injury and multiple penetrating wounds of the chest and stomach complicated by massive hemorrhage. When the PIP was localized in the abdominal cavity, enterobacteria and bacteroides were the main pathogens: 49.4 +/- 2.1 and 32.8 +/- 1.4 per cent, respectively. When the PIP was localized in the thoracic cavity, the most frequent pathogens were staphylococci, Pseudomonas aeruginosa, and enterobacteria: 26.5 +/- 1.4, 24.6 +/- 1.4 and 13.3 +/- 0.8 per cent, respectively. In all the cases high variability of the antibiotic susceptibility of the isolates and predominance of the strains resistant to 5 or more drugs were observed. A suppressive effect of thienam on the immune system was revealed. The immunocorrection in parallel with the antibiotic therapy made it possible to prevent further development of immune deficiency and to recover the bactericidal potency of the phagocyting cells. The use of various physiochemical methods in complex treatment of PIPs is substantiated.     

Dynamics of antibiotic resistance of purulent septic pathogens at an emergency facility]

The predominant pathogens at the emergency medicine hospital were analysed and its resistance to antibiotics was investigated in dynamics. The susceptibility of the pathogens was analysed by the method of dynamic equalibration. Statistically significant reduction of resistant bacteria isolation was demonstrated for 2 species of 7--that is S. aureus and E. faecalis regarding 4 antibiotics. The ratio of staphylococci resistant to cefazolin, ceftazidime, doxycyclin reduced, the ratio of enterococci resistant to chloramphenicol and doxycyclin also diminished. No correlation was demonstrated between the pathogen isolation frequency and ratio of resistant strains.     

Effect of calmodulin inhibitors on the contraction and relaxation of the heart muscle

The calmodulin inhibitor trifluoroperazine (5 microM) diminished the velocity of contraction and relaxation of the guinea-pig papillary muscle by 31 and 53%, respectively. Methophenazine showed approximately the same affinity to both calmodulin and trifluoroperazine and nearly 40-fold less affinity to troponin. Methophenazine (5 microM) did not change the contraction velocity and diminished the relaxation velocity ty 21%. It is suggested that calmodulin participates mainly in the control of myocardial relaxation.     

The source of non-heme iron that binds nitric oxide in cultivated macrophages.

In cultured macrophages (J 774 line) a decrease in iron-sulfur centers (ISC) was not observed after 5 min treatment with nitric oxide (NO) (10(-7) M NO/10(7) cells). The content of these centers was measured by electron spin resonance (ESR) spectroscopy at 16-60 K. However, the appearance of a characteristic ESR signal at g(av) = 2.03 indicated the formation of dinitrosyl iron complex (DNIC) in these cells. These findings suggest that loosely bound non-heme iron (free iron) but not iron from ISC is mainly involved in DNIC formation. ISC might release iron for DNIC formation after their destruction induced by the products of NO oxidation (NO2, N2O3, etc).     

The effect of temperature and Ca2+ on the interaction of high-density lipoproteins with epithelial cells in the human small intestine

The effect of temperature and Ca2+ ions on the interaction of high-density lipoprotein (HDL3) with human enterocytes was studied. It was shown that Kd measured at 4 degrees C is similar to that at 37 degrees C. Maximal number of binding sites at 37 degrees C is 15-fold times higher than that at 4 degrees C. EDTA (10 mM) and CaCl2 (0.5-5 mM) did not affect binding and uptake of HDL3 by human enterocytes. The obtained results indicate that HDL3-binding with these cells depends on temperature and does not depend on Ca2+ ions.     

Bacteriological monitoring of infective agents of purulent septic diseases in an emergency hospital

During the period of 1995-2001 bacteriological examination of 13,842 patients with purulent septic diseases (PSD) was carried out. The statistical processing of data revealed that equalization of the dynamic rows of intensive and extensive values characterizing the number of patients with PSD caused by etiologically important infective agents made it possible to evaluate the reliability of information. A trend to increased etiological importance of the genera Pseudomonas, Escherichia and Klebsiella was established. The number of diseases caused by Staphylococcus, Streptococcus, Enterococcus and Proteus decreased.