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Aim: Study of taxonomical structure ofwound infection agents, prevalence of mixes, and detection of character of their possible connection with the results of various microorganisms population interaction in septic wounds., Materials and Methods: A microbiological study of material from patients with wound infection (WI), 582 of those were cured in reanimation and intensive therapy departments (RITD; group 1) and 1455 - in surgical departments (SD; group 2), was performed. Taxonomic membership and ability to coexist was determined in 4129 microorganisms strains. Etiological role of the agents was evaluated by using values of consistency rate (CR). Species that were present in more than 50% of samples were considered consistent, in 25 to 50%--additional, and in less than 25%--random. Frequency rates (FR) were also determined, that is the fraction of a certain species (genus) of the microorganism (in %) from all the isolated cultures that correspond to 100%. For the determination of the significance of individual species of the agent in the structure of mixed microorganism populations, FR - their fraction (%) in mixed population from the number of strains of this species that correspond to 100% - was calculated., Results: A significant part of the microorganisms strains, more frequently in reanimation department (65.5%), caused wound suppuration in populations mixed with other species of the agents. In reanimation and surgical departments consistent species of wound infection agents were not detected. A leading etiological role of Staphylococcus aureus (FR 19.2% and 23.9%) was determined, and FR of S. aureus strains in mixes was 64.6% in RITD and 46.8% in SD. The parameters ofotheragents of WI in the comparison groups were similar. However FR among mixes in RITD were significantly higher for streptococci that do not belong to S. pyogenes species (72,5%), and also nonfermentative microorganisms (67,2%), and in SD - in Klebsiella pneumoniae mixes. For agents of wound infection especially in RITD, low species diversity was characteristic and the number of mixes variants is significantly higher. In RITD mixed infections develop more frequently, and the ecological community of microorganisms reaches higher values than in SD., Conclusion: During the analysis of microbiologi-cal data in RITD and SD general patterns and specific features of taxonomical structure, prevalence of mixed populations and character of their ecological community in wound infection was determined.

Aim: To study etiologic role of microorganisms during wound infection and elucidation of their populations interaction in patientswith burns., Materials and Methods: 2137 patients with wound infection treated in burn center were studied. 3179 samples of wound exudates and 6501 strains of microorganisms were studied. Assessment of microorganism's etiologic role was carried out using results of calculation of various statistic indexes, including indexes of ecological similarities of microorganisms in the wound (indexes of contamination, prevalence or persistence, incidence). Ecological similarity of wounds' microflora was determined by calculation of the coefficient Kj., Results: It was established that Staphylococcus aureus is the most common cause of mono- and mixed wound infections. It was determined that Kj value for common agents points to antagonism or associative interaction. During particular time periods of the study values of Kj significantly differed and depended from species. Specifically, for Pseudomonas aeruginosa the values of Kj were equal or exceeded 30% during several years. It was the first time when correlation between persistence and ecological similarity indexes was studied in agents of wound infections., Conclusion: In order to reveal factors influencing on microbial etiology of mixed wound infections it is reasonable to consider the nature of interspecies interactions of causative agents.

Aim: The objective of this study was to assess dynamics of prevalence of hemotransmissive viral infections (HTVI) markers as mono- or mixed infections in patients admitted to Sklifosovsky Research Institute of Emergency Medicine., Materials and Methods: Two hundred thirty-five thousands and seventy patients admitted to the Institute during 1998 - 2007 were screened for the presence of laboratory markers of HTVI (antibodies to HIV, HBsAg, and anti-HCV)., Results: The long-term screening revealed 27,942 (11.9%) persons positive for laboratory markers, of which 3,099 (11.1%) were positive for >1 marker. It was established that HIV infection as well as viral hepatitis B and C have different level of similarity and ability to coexist. HIV infection was more frequently detected in association with other infections, whereas hepatitis B and C--as monoinfections., Conclusion: Attempt to consider the mutual influence of HTVI on their prevalence from the view of modern concept of microorganisms' ecology was made. Computation of Jaccard similarity coefficient showed that HIV and HCV have the greatest abilities for coexistence, whereas HIV and HBV--the smallest.

The study deals with the current topical problem in the development of a laboratory algorithm for the detection of early stages of HIV infection and for the creation of a monitoring system on this basis for the spread of drug-resistant HIV-1 strains. The paper presents the results of experimental examination of the most accessible health care methods for the differential diagnosis of early HIV infection, by using the test systems in Russia and gives practical recommendations on their application.

Comparative study of widely distributed on Russian market commercial test-systems for HBsAg detection by enzyme immunoassay was performed. Panel of serum samples containing mutant forms of HBsAg was developed for the study. It showed that only 2 out of 7 studied test-systems are able to detect mutant forms of HBsAg with the same sensitivity as "wild-type" forms of HBsAg. Test-systems based only on monoclonal antibodies did not detect HBsAg with G145R substitution in concentration 5 ng/ml. The study confirms the relevance of problem of HBsAg-mutants detection for hepatitis B immunodiagnostics.

Algorithm of serologic screening for HBsAg-mutants in hepatitis B virus (HBV) carriers with high level of HBsAg was developed which is based on the detection of defects of interactions of serum HBsAg with monoclonal anti-HBs realizing as a decrease of ELISA sensitivity in 10 times or more during serial 10-fold dilutions. During 1st stage commercial test-systems based on monoclonal antibodies was used to select serum samples with discrepancy of test results. During 2nd stage HBsAg contained in selected sera was analyzed by the panel of monoclonal and polyclonal anti-HBs conjugates using decrease in ELISA sensitivity as a criterion. Serum samples from 2510 chronic carriers of HBV with high level of HBsAg were studied. 19 samples with discrepant results were found. Subsequent characterization of HBsAg with panel of 11 monoclonal and 1 polyclonal conjugates allowed to distinguish groups of sera with specific serologic "portraits". Atypical features of HBsAg were confirmed by genotyping 9 of 19 samples. Analysis of primary nucleotide sequence revealed serologically meaningful mutations in S-gene of HBV in all 9 isolates: 3 of them contained substitution mutation G145R, 5--S143L, and one--T143M. Distribution of mutations in HBsAg corresponded with specific serologic "portraits". Prevalence of HBsAg mutations in HBV carriers with high level of HBsAg was assessed for the first time: prevalence of G145R, S143L/T143M mutations, and all serologically atypical variants was 0.12%, 0.24%, and 0.76% respectively. Developed algorithm was proposed for epidemiologic monitoring of HBsAg-mutants of HBVand control of diagnostic test-systems.

HIV positive patients needing urgent treatment have become reality in the clinical practice of the multiprofile hospital of the Sklifosovsky Research Institute of Emergency Aid. 243,030 patients and 55,163 donors were examined at the Laboratory of Clinical Immunology and AIDS Diagnostics during the period of 1989-2001, and among the examinees 814 patients and 13 donors were found to be HIV-infected. The highest detection rate of HIV-infected patients was registered in the poisoning center, the somatic-psychiatric and endotoxicosis departments. After the period of a sharp rise in the number of HIV-positive patients (1997-2000) a decrease in their proportion among hospitalized patients was registered in 2001.

The comparative study of the relationship between the levels of serum antibodies to the antigens of opportunistic microorganisms of 5 genera (Pseudomonas, Proteus, Staphylococcus, Klebsiella, Escherichia) and the microbial status was carried out. A total of 854 patients from 10 profile departments of a surgical hospital were examined. Population analysis and statistical methods of processing the results of the examination of 353 practically healthy subjects and 268 blood and plasma donors permitted the norms for the levels of specific antimicrobial antibodies (decreased, normal, elevated levels) were established. The constancy coefficients of Pseudomonas, Staphylococcus, Klebsiella, Escherichia and the number of patients with elevated titers of specific serum antibodies were found to be positively correlated (r = +0.47-0.89, p < 0.01). The data thus obtained made it possible to substantiate the importance of population serological investigations for the evaluation of the epidemiological situation in the surgical hospital.