[Biochemical characteristics of ticks of the families Argasidae and Ixodidae].

Polyacrylamide gel electrophoresis was used to study homogenate supernatants from the bloodsucking ticks (Argasidae and Ixodidae) belonging to 8 different genera and species. Differences were found in the electrophoretic mobility of protein fractions in adult ticks of these two different families and between several genera of Ixodes ticks (such as Haemaphysalis, Hyalomma, Dermacentor, Rhipicephalus and Ixodes). Argasidae ticks were found to have generic and even species-specific differences at the nymphal stage of development. A. lahorensis nymph-3 contained 5 protein fractions; O. papillipes had 2 fractions, and O. moubata had 3 fractions. Electrophoretic protein separation showed the equal number of protein fractions within one genus of ticks. At the larval stage, the tick homogenates were always found to have one protein fraction. The hemolymph of O. papillipes and O. moubata ticks displayed differences between the imago and nymph-3. A new biochemical marker was proposed to establish a species affinity.

[Information-computer modeling of suppression of the infectious tuberculosis process through sterilization of medical instrumentation and equipment by using electrochemically activated aqueous solutions]. / Informatsionno-komp'iuternoe modelirovanie sderzhivaniia infektsionnogo tuberkuleznogo protessa za schet sterilizatsii meditsinskogo instrumentariia i oborudovaniia s ispol'zovaniem élektrokhimicheski aktivirovannykh vodnykh rastvorov.

The paper deals with the topical problem in the informational computer simulation of suppression of an infectious tuberculosis process by applying electrochemically activated aqueous solutions in order to sterilize medical instruments and equipment. The efficiency of use of electrochemically activated aqueous solutions for sterilization of medical instruments and equipment and for disinfection of other contaminated objects was evaluated by an computer-aided experiment and a retrospective analysis of the epidemic situation by using the original mathematical models of infectious processes by taking into account the aspects of medical engineering technology.

[The reciprocal influence of Escherichia coli and Salmonella bacteria in a mixed infection of Ornithodoros papillipes Birula ticks]. / Vzaimovliianie bakterii kishechnoi palochki i sal'monell pri smeshannom zarazhenii kleshchei Ornithodoros papillipes Birula.

The paper presents and analyzes the results of experiments on the Escherichia coli-Salmonella relationships in combined infection of Ornithodoros papillipes ticks. The findings have led to the following conclusions. The body of hungry adult O. papillipes ticks can retain the pathogen of Salmonella infection for a month. This model object is also favourable for avirulent E. coli strain persistent in the body's cavity both alone and in combination with Salmonella typhimurium strain in a 1:1 ratio. Binary carriage in hungry Ornithodoros papillipes ticks revealed that the ticks associated with Salmonella typhimurium and E. coli 083 mcl + lyz No 225, microcine and lysozyme producers, are freed of pathogenic bacteria during 24 hours. The initial bacteria E. coli 083 mcl also suppress salmonellae; however, their elimination occurs much later--in 5 days. Calculating the correlation between the pairs (S. typhi and E. coli) has revealed a linear functional relationship of the rate of E. coli growth to S. typhimurium suppression.

[Assessment of the effectiveness of medical instruments sterilization by electrochemically activated solutions and computer modeling of the dynamics of hospital infections]. / Otsenka éffektivnosti sterilizatsii meditsinskogo instrumentariia élektrokhimicheski aktivirovannymi rastvorami metodom komp'iuternogo modelirovaniia dinamiki vnutribol'nichnykh infektsii.

The paper sets a task of evaluating the efficiency of electrochemically activated solution sterilization of medical instruments, which is tackled by the computer-aided simulation of time course of nosocomial HIV infection.

[A dynamic model for analyzing and predicting the epidemic process in typhoid fever]. / Dinamicheskaia model' dlia analiza i prognozirovaniia épidemicheskogo protsessa briushnogo tifa.

The results of calculations and theoretical considerations on processes of the spread of typhoid fever, made with the use of a new mathematical model which is based on the model proposed by B. Cvjetanovic, further developed and improved. In this new model the latest phenomenology of the description of the processes of the spread of typhoid fever in the heterogeneous susceptible layer of the human population was used. A computer program for the new mathematical model of typhoid fever has been realized on a IBM PC/AT-386, which makes it possible to carry out prognostic analytical studies of the dynamics of the spread of typhoid fever at endemic territories. This program has been used for making calculations in connection with the analysis and prognostication of typhoid fever morbidity and mortality processes in St.-Petersburg.

[A prognostic model of hepatitis A morbidity]. / Prognosticheskaia model' zabolevaemosti gepatitom A.

The growing interest to the study of the processes of the spread of hepatitis A (HA) in big cities of our country has stimulated the development of a new prognostic model at the Gamaleia Research Institute of Epidemiology and Microbiology. The model specifically takes into account a number of factors linked with the dynamics of the development of the disease in 6 stages and some regularities in the seasonal rises of HA morbidity. Quantitative relations in the mathematical model are determined by a system of nonlinear integral-differential equations with the first order partial derivatives and under the integral type boundary conditions, which increases the strictness of modeling of HA. The use of this new model has made it possible to carry out the prognostic-analytical study of HA morbidity among children in Perm and to evaluate a decrease in HA morbidity due to the hypothetical vaccination of children in spring months.

[The HIV infection processes in a hospital: the prognostic possibilities]. / Protsessy zarazheniia VICh v bol'nitse, vozmozhnosti prognozirovaniia.

The method of mathematical simulation of the processes of HIV infection in hospitals and clinics is proposed with the aim of predicting the spread of HIV infection throughout the territory of this country. An original mathematical model reproducing, on the whole, the essential properties of HIV infection processes in the course of medical interventions requiring skin punctures has been worked out. An adequate mathematical and computer model imitating the process of HIV infection in a hospital is a convenient instrument for making up prognostic evaluation and for the epidemiological analysis of cases of HIV infection occurring at medical institutions throughout this country.