[Probiotics as an items of increasing the effectiveness of treatment of community-acquired pneumonia in adolescents].

The aim of the work was to evaluate the efficiency of microbial probiotics Vitaflor and metabolic probiotic Aktoflor-C in complex treatment of community-acquired pneumonia in adolescents in a hospital. The observation involved 38 children aged 11 to 18 years with radiologically verified community-acquired pneumonia, including 23 boys and 15 girls. Patients were divided in 3 groups. Patients in group 1 (n = 13) simultaneously with the antibiotic therapy received per os Vitaflor probiotic containing symbiotic strains of Lactobacillus acidophilus; patients in group 2 (n = 10) along with antibiotic therapy received per os metabolic probiotic Aktoflor-C, containing low molecular weight exometabolites bacteria; patient of the comparison group (n = 15) received antibiotic therapy only. The effectiveness of the used treatment schemes was assessed on the dynamics of the gut state microbiot acoarding to an extended bacteriological examination of faecal flora, level of saliva IgA secretory (before and after treatment), the dynamics of SF-36 quality of life 1 month after discharge from hospital. Was conducted a study of economic efficiency of different modes of therapy. Results showed that adolescents with community-acquired pneumonia during standard antibiotic therapy indicated development of dysbiotic bowel disturbances in the form of reliable oppression of the bifidobacteria and laktoflora. Dysbiosis of the microbial associations are not conducive to proper implementation of immune and nutritional functions of the intestine that shows the imperfection of rehabilitation of patients with pneumonia according to the evaluation of SF-36 quality of life. Pharmacoeconomic analysis revealed the benefits of probiotic metabolic type "Aktoflor" used in addition to standard therapy of community-acquired pneumonia in adolescents.

[Choice of probiotic for rational therapy of infection caused by Klebsiella in children].

AIM: To choose lactobacilli-contained probiotic for complex treatment of acute enteric infection caused by Klebsiella in infants. MATERIALS AND METHODS: On the basis of bacteriological analysis the group consisting of 40 infants with acute enteric infection caused by Klebsiella was formed. Efficacy of three probiotic preparations--lactobacterin, vitaflor, and biobacton--was assessed depending on biological features of causative agents and contents of lactobacilli and bifidobacteria in obligate gut microflora. Intraspecies antagonistic characteristics of manufacturing strains of lactobacilli against 9 clinical isolates of K. pneumoniae and 8 strains of indigenous lactoflora, as well as interspecies antagonism between Klebsiella and probiotic and indigenous strains of lactoflora were studied. RESULTS: It was shown that complex therapy of Klebsiella infection in infants using vitaflor or biobacton promoted elimination of K. pneumoniae and restoration of indigenous microflora which became apparent in significant increase of titer of lactobacilli. In vitro maximal antagonism to K. pneumoniae was noted for vitaflor, lactobacterin and heteroenzyme autostrains of ill children's lactoflora. Contrantagonism to lactoflora was typical for slowly growing strains of Klebsiella. CONCLUSION: It is therapeutically rational to use vitaflor, which promotes rapid elimination of infectious agent, in initial phase of acute infection caused by Klebsiella, and biobacton, which increases the titers of indigenous lactoflora, in phase of convalescence.

[Regulatory functions of bacterial exometabolites].

This review deals with the issue of growth autoregulation and survival in bacterial cultures under starvation conditions. Based on our results and on published data, the conclusion has been drawn that low-molecular products of metabolism (carboxylic acids, amino acids, and other metabolites) perform regulatory functions. The same compounds also control the ecological relationship between microorganisms at the interspecific level, and affect their antagonistic activity. It is suggested that complexes of bacterial metabolites can be used for controlling the composition of various microbiocenosis, including those of humans.

[Prospects of the development of probiotic preparations on the basis of the "quorum sensing" in bacteria].

The regulation of definite bacterial genes is known to occur, depending on the density of cell population, on the principle of autoinduction named "quorum sensing". The characteristic sign of all regulatory systems working on the principle of "quorum sensing" is the presence of two regulatory proteins: Luxl-like, responsible for the binding of its autoinductor, which makes it possible for the newly formed complex to bind with the promoter of the specific target gene and activate its transcription. The phenomenon of a rise in the concentration of the secreted autoinductor, depending on the increase of the density of cell culture which forms the basis of the "quorum sensing" systems, is analyzed with a view to the development of new therapeutic remedies.

[The bacterial QS-systems and prospects of creation of new metabolic probiotic preparations].

Biological functions of exometabolits of various bacterial species were analyzed from Quorum Sensing position, which showed that the functional activity of microbiocenosis is in many respects determined by the system of metabolic regulation. Possibility of changing the composition of complex microbial communities with low-molecular compounds, products of bacterial cell vital activity, is grounded from theoretical point of view. The authors adduce data on the effects of a synthetic composition on the basis of E. coli metabolites, an ingredient of colibacterin, a probiotic preparation. The preparation demonstrated a high stimulating activity towards a range of microorganisms of normal microflora, and an ability to improve the condition of intestinal epitelial cells. The results may substantiate application of metabolic probiotics for correction of intestinal microflora in man.

[Concept of a probiotic preparation, containing original microbial metabolites].

The biological functions of Escherichia coli M-17 exometabolites, contained in the synthetic composition of the autostimulating preparation "Actoflor-C", were evaluated. As shown by in vitro experiments, the composition had higher stimulating activity with respectto some microorganisms of the normal microflora, in comparison with the prototype preparation "Actoflor". High doses of the preparation "Actoflor-C" were supposedly capable of having not only positive influence on the development of microbiocenosis, but also of producing therapeutic action and primarily on intestinal epithelial cells by compensating the insufficient supply of bacterial metabolites in dysbiotic states. The presented data made it possible to believe that the functional activity of microbiocenosis was greatly determined by the system of metabolic regulation. The presented results formed the basis for the use of bacterial metabolites in the therapeutic of microbiocenosis in man.

[Isolation and identification of growth stimulators of Escherichia coli M-17]. / Vydelenie i identifikatsiia autostimuliatorov rosta Eshercichia coli M-17.

The stimulating activity of E. coli M-17 culture fluid (CF) is determined by the action of low-molecular exometabolites, readily soluble in water. The high-molecular fraction was removed from CF by ultrafiltration, the growth stimulators were adsorbed on anion exchange resin and eluated at pH 3.1. In further purification HPLC and chromatography on TSK gel HW-40 were used. The identification of compounds was carried out by the methods of thin-layer chromatography, amino acid analysis and 1H-NMR spectroscopy. Glutamic acid (glutamine) and succinic acid proved to be the most active growth autostimulators. The data of biological testing made it possible to believe that CF also contained less active stimulators and/or synergic substances which had no their own activity, but stimulated growth, acting jointly with other compounds. In view of the definite specificity of action observed in initial CF, some differences in the spectrum of growth stimulators of other E. coli strains may be supposed.

[Comparative study of effects of Escherichia coli M-17 exometabolites and fructooligosaccharides on the growth and antagonistic activity of Lactobacilli]. / Sravnitel'noe izuchenie deistviia ékzometabolitov Escherichia coli M-17 i fruktooligosakharidov na rost i antagonisticheskuiu aktivnost' laktobatsill.

Facts concerning the evaluation of the influence of E. coli M17 exometabolites and fructooligosaccharides (FOS) on the growth and antagonistic activity of lactobacilli are presented. As revealed by these facts, preparation "Aktoflor" accelerates the growth of lactobacillary cultures, increases the final yield of biomass and antagonistic activity. E. coli M17 exometabolites contained in "Aktoflor" have been shown to be more active in comparison with FOS. The character of their influence on lactobacilli is discussed and the conclusion is made that the restoration and maintenance of eubiosis is greatly determined by the pool of metabolites excreted by the bacteria.

[The action of a preparation of Escherichia coli M-17 growth autostimulants (Actoflor) on the growth of pure and mixed bacterial cultures]. / Deistvie preparata autostimuliatorov rosta Escherichia coli M-17 (Aktoflor) na rost chistykh i smeshannykh kul'tur bakterii.

The effect of the preparation of E. coli M-17 low-molecular exometabolites (Actoflor), containing growth autostimulators, on the growth of pure cultures of E. coli M-17 E. coli K-12, Salmonella enteritidis, Serratia marcescens and Bifidobacterium adolescentis MC-42 was studied. This preparation was shown to stimulate the growth of all above-mentioned bacteria. The addition of Actoflor also led to the acceleration of growth in the cultivation of mixed cultures of E. coli M-17 with E. coli K-12 (or S. enteritidis), the producer strain (E. coli M-17) showing the highest degree of acceleration. Moreover, the action of Actoflor led to the elimination of competitor strains and to the increase of the antagonistic activity of E. coli M-17. Actoflor may be supposedly used as a therapeutic or prophylactic remedy.

[Effect of Actoflor preparations on survival of Escherichia coli M-17 and Salmonella enteritidis under starvation conditions in mixed cultures]. / Vliianie preparatov "Aktoflor" na vyzhivaemost' Escherichia coli M-17 i Salmonella enteritidis pri golodanii v smeshannykh kul'turakh.

The viability of E. coli M-17 and S. enteritidis under starvation conditions in mono- and mixed cultures was studied. E. coli M-17 showed greater capacity for survival in mixed cultures than in monocultures, while for S. enteritidis the contrary was true. Preparations "Actoflor" enhanced the antagonistic activity of E. coli M-17, ensuring its absolute selective advantage under starvation conditions in mixed cultures. The role of E. coli M-17 low-molecular exometabolites is discussed; they are probably an important factor in the antagonistic activity of these microorganisms.

[Change in conformation of proteins in aqueous solutions of heterofunctional nonelectrolytes]. / Izmenenie konformatsii belkov v vodnykh rastvorakh geterofunktsional'nykh neélektrolitov.

In narrow ranges of concentrations of heterofunctional nonelectrolytes in aqueous solutions, structural transitions occur, which manifest themselves in the self-association of nonelectrolytes molecules and are accompanied by the screening of their hydrophobic groups from the contact with the solvent. In the same nonelectrolytes concentration ranges, conformational changes of protein molecules in solutions take place. The compatibility of the concentration ranges of these two processes is due to the fact that when nonelectrolytes molecules are extruded from the network of hydrogen bonds during the structural transition, both the self-association of nonelectrolytes molecules and their incorporation into the hydrate shell of the protein occur. The dehydration of the protein results in the disturbance of the balance of intra- and intermolecular interactions maintaining the native protein structure, which leads to the rearrangement of the macromolecule conformation.

[Release of protein into the extracellular space as a nonspecific response to stress in Escherichia coli]. / Vydelenie belka vo vnekletochnoe prostranstvo kak nespetsificheskaia reaktsiia Escherichia coli na stress.

This paper is concerned with the kinetics of excretion of fluorescent tryptophan-containing proteins from Escherichia coli cells kept in physiological saline at room temperature or incubated at 42, 48, and 55 degrees C. The kinetic curves of the extracellular concentration of protein can be described by parameters T and C, where C is the stationary extracellular concentration of the protein and T is the time in which the given concentration is reached. T was found to be a variable, and C was a constant independent of the type and strength of the stress. During the protein release, the viability of the cells was maintained at the initial level, but, after the concentration of the protein reached a stationary value, the culture cells died exponentially. All this allows the protein release into extracellular medium to be considered as a nonspecific response of E. coli to stress. The protein excretion was analyzed with reference to the data on the kinetics of release of other UV-absorbing compounds from the cells.

[Mechanism of specific chromogenic reaction by Klebsiella spp. on nutrient medium with 5-aminosalicylic acid]. / Mekhanizm spetsificheskoi khromogennoi reaktsii Klebsiella spp. na pitatel'noi srede s 5-aminosalitsilovoi kislotoi.

The nature of the factor and the mechanism of color reaction with 5-aminosalicylic acid (5-ASA) inherent in bacteria of the genus Klebsiella were investigated. The color reaction was shown to proceed in two stages. During the first stage, occurring in aerobic and anaerobic conditions, the tested strains of Klebsiella decarboxylize 5-ASA yielding CO2 and p-aminophenol, which is a colorless product. During the next strictly aerobic stage which proceeds without participation of bacteria or their exoenzymes, p-aminophenol is oxidized by the air oxygen forming the dark-brown polymers. The color reaction shows high substrate specificity. It is suggested that the color reaction is realized by a previously unknown lyase-type enzyme 5-aminosalicylate decarboxylase (5-aminosalicylate-carboxy-lyase) localized inside the Klebsiella cells.

[Survival of Escherichia coli cells during storage in suspensions of varying concentrations]. / Vyzhivaemost' kletok Escherichia coli pri khranenii v suspenziiakh razlichnoi kontsentratsii.

The presence of positive correlative connection between death rate of Escherichia coli M-17 cells and the density of their suspension have been estimated. It has been shown, that the accumulation in extracellular medium (ECM) of death-stimulating (DS) metabolites, the concentration of which was higher in the suspensions of higher densities, was the immediate cause of the acceleration of death in suspensions with densities higher than 1 x 10(9) cells/ml. DS metabolites could be removed from ECM by adsorption or dialysis, and, thus, they had comparably low molecular mass. The presence of DS metabolites led to the acceleration of death of test-cultures E. coli M-17. The filtrates of ECM of suspensions with density lower than 1 x 10(9) cells/ml did not accelerate the death rate of test-cultures, and, most probably, did not contain any DS-substances. It is supposed, that the role of DS-substances is the maintenance of optimal size of the population of bacteria. The low effective concentrations of these substances make it possible to consider that their functions are nothing but regulatory.

[Temperature changes of extracellular media state on a bacterial suspension]. / Temperaturnye izmeneniia sostoianiia vnekletochnoi sredy v bakterial'noi suspenzii.

Within temperature intervals 30-40 degrees C for bacterial suspension of E. coli and 24-34 degrees C for B. flavum the extracellular medium exists in a specific state. Water in the extracellular medium is stabilized by increased hydrophobicity of extracellular protein molecules surface due to proteins conformational change. The total amount of UV-absorbing metabolites is decreased as a result of activation of microorganisms transport systems. The temperature intervals of these processes are different for both types of the microorganisms and coincide with their temperature optima of vital activity.