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By means of spectrophotometric assay we investigated interaction of the dye Congo red (CR) with fibrils of model proteins--hen egg white lysozyme, recombinant human beta2-microglobulin (b2M) and recombinant human transthyretin (TTR). The commercial dye sample was found to contain a significant amount of impurities. Methods for the dye purification are disclosed and CR molar extinction coefficient at 490 nm (ε490) was determined to be 3.3 x 10(4) M(-1) x cm(-1) at pH above 6.0. Formation of the CR-fibril complex results in changes in the dye visible absorption spectrum. According to the data on titration of fibril solutions with excess of the dye, CR binds to lysozyme fibrils at a ratio of about 5 molecules per protein monomer within fibril structure, to b2M fibrils--about 4 molecules per monomer, to TTR fibrils--about 4 molecules per subunit of the protein.

The objective of the investigation was to study the biological properties (antilysozyme activity (ALA), biofilm formation (BFF), and virulence factors) of different Enterobacteriaceae species isolated from Bithyniidae mollusks and their habitats. A total of 117 strains isolated from Bithyniidae mollusks of the genera Codiella and Bithynia and those from their habitats were the material to be studied. Thus, comparison of the mean values of ALA in Enterobacteriaceae species suggests that the strains isolated from the mollusks and their aqueous habitat did not virtually differ in this indicator. Also, there were no statistically significant differences in the detection rate of the Enterobacteriaceae strains having a pronounced antilysozyme activity and in that of mollusks circulating in the aqueous habitat when compared with the strains isolated from the mollusks. Comparison of BFF in the aqueous bacterial strains and mollusk microbiota representatives revealed the highest values in the former; just lower value was noted in the latter. Soil Enterobacteriaceae isolates had very low BFF values.

Aim: Determination of modulating effect of acid-base state of medium for cultivation of enterobacteria on activity of C-type lysozyme., Materials and Methods: Escherichia coli BL21 (DE3) strain for protein expression, Escherichia coli K12 MG1655 model strain, Escherichia coli No. 242 strain, isolated from intestine biotope; 2 Klebsiella pneumoniae strains, one of those contained plasmid homologue of periplasmatic lysozyme inhibitor gene pliC; 1 typical Salmonella enterica ATCC 14028 strain and a Micrococcus luteus ATCC 15307 strain as a control--served as material for the study. The bacteria were cultivated for 24 hours in 2 ml of liquid medium LB at 37 degrees C, 250 rpm. Determination of antilysozyme activity (ALA) was carried out by a photonepehlometrical method according to O.V. Bukharin et al. (1999) with alterations., Results: All the studied microorganisms, including Micrococcus luteus, at the specified conditions 24 hours after cultivation were established to change the pH of the liquid nutrient medium LB from the initial value of 6.6 ± 0.1 to 8.2 ± 0.2 units. ALA determination in the cultivation medium without buffer correction was accompanied by a decline of lysozyme activity at an order of magnitude. The effect was absent during ALA measurement by a standard technique., Conclusion: The local shift of acid-base state of biotope under the conditions of buffer system insufficiency results in a reversible alteration of antimicrobial activity of muramidase, that among other non-specific factors of the environment determines the background of interactions on the level of associative symbiosis. This aspect should be taken into consideration during development of models, that are close to real conditions of microsymbiocenotical interactions.

The influence ofvarious surfactants (anionic sodium dodecyl sulfate, SDS, cationic dodecyltrimethylarnmonium bromide, DTAB, and zwitterionic cocoamidopropylbetaine, CAPB) on the activity of the chicken egg lysozyme is investigated. Lysis of Gram-positive bacteria by the enzyme was carried out at pH 7.2 and ionic strength of 0.15 M. It was found that at low SDS and DTAB concentrations (less than 1 x 10(-5) M) the bacteriolytic activity increases by 30-140%. At higher concentrations (1 x 10(-5) - 1 x 10(4) M) the activity returns to the level observed in the absence of the surfactants. The elevated activity correlated with the formation of hydrophobic lysozyme-surfactant complexes. Introduction of CAPB at concentrations above 1 x 10(-5) M sig, nificantly diminished the bacteriolytic activity due to CAPB induced aggregation of lysozyme.

Two families of specific inhibitors of type C lysozyme (Ivy and PliC) secreted from the periplasmic space are known in enterobacteria. Microbial capacity for distant lysozyme inactivation (antilysozyme activity) is most pronounced in the strains and species carrying homologues of the pliCgene. The pliC homologue localized in a -200-kbp megaplasmid of Klebsiella pneumoniae was shown to differ significantly in the amino acid composition of the coded polypeptide. Similar to the Salmonella enterica pliC homologue, it possesses a detachable signal part and contains identical functionally critical amino acids of the active center of the inhibitor. Antilysozyme activity of the pliC-positive K. pneumoniae strains was observed at the level corresponding to the highest values found inpliC-positive S. enterica. High level of the antilysozyme activity in K. pneumoniae strains containing the plasmid pliC homologue was found in all studied strains, unlike S. enterica strains carrying the known chromosomal pliC homologue.

From the highly purified but lowly active recombinant protein Destabilas-Lysozyme (Dest-Lys) by use cation-exchange column TSK CM 3-SW chromatography, it was separated non-active fraction IV, contained 90% of protein. Fractions I, II and III, represented proteins with lysozyme and isopeptidase activities. Their lysozyme activity correlates with the activity of natural Des-Lys. The ratio of the activities in fractions I - III is such, that maximal lysozyme activity is concentrated in fraction III, isopeptidase - in fraction I. It is discussed the possibility of Dest-Lys different functions regulation is depended on the formation of protein complex forms.

Aim: Evaluation of phenotypes and pathogenicity factors of 476 opportunistic bacteria isolated from respiratory samples of 973 children with community-acquired pneumonia and 36 children without respiratory infection symptoms., Materials and Methods: Quantitative method of tracheal aspirate and nasopharyngeal swab seeding into certified nutrient media was used, identification was carried out according to standard techniques., Results: Adhesive, "anti-interferon", anti-lysozyme and inherent bactericidal activity of Escherichia coli and Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter spp. were established to ensure in combination with known aggression factors their colonization advantage compared with other pneumopathogens. Adhesion indexes of Gram-negative bacteria lower than 2.5 are shown as markers of invasive strains. Anti-lysozyme activity level lower than 2.14 microg/ml and lack of "anti-interferon" activity characterize non-invasive opportunistic bacteria strains., Conclusion: The detected phenotypic features of opportunistic bacteria may be used in clinical practice for evaluatio of etiologic importance of microorganisms isolated from tracheal aspirate in pneumonia patients.

Objective: Ouraim was to study influence of acute somatic pain on lysozyme activity of rats of different age: newborn, rats after eye opening, rats at the age of a month, adult and old rats., Methods: Lysozyme activity was checked before pain irritation and 2, 30, 60, 120, 180min afterwards using Dorofeychuk's method in our modification. Pain effect was modeling by electrical stimulation., Results: activity of lysozyme was 0. 434±0. 01 units in intact newborn rats, It was higher than in adult rats - 0.260 ±0.01 units (p <0.001) and it was unchanged during the experiment. We found low lysozyme activity in rats after eye opening - 0.015±0.003 units and it was stable during the experiment. Rats at the age ofa month had diphasic reaction: lysozyme activity was 0.191±0.01 units in intact rats, it increased up to 0.378±0.01 units (p <0.001) in 2 min after painful irritation and it decreased up to 0.113±0.02 units (p <0.001) in 30 min. Lysozyme activity was 0.260±0.01 units. Single-phase reaction was determined after acute painful irritation: increase of lysozyme activity after acute somatic pain up to 0,450±0,014 units (p <0.001). Lysozyme activity was 0.246±0.02 units in blood plasma of old rats. It decreased up to 0.1701±0.01 units (p <0.01) after painful irritation and it was 0.387±0.01 (p <0.001) in the end of the experiment., Conclusion: Response on pain irritation has differences in different groups. The common vector of pain response was the increase of lysozyme activity in rats at the age of a month, adult rats, rats after eye opening and old rats. Reaction of increasing lysozyme activity was strongly detected in adult rats. The results demonstrate preventive lasozyme resistance to potential tissue damage or contamination.

The content of lysozyme as an indicator of nonspecific immunity in kidney, liver, spleen, and blood serum in 8 fish species of the order Gadiformes and the order Pleuronectiformes was analyzed. The Gadiformes are characterized by a very low level of enzyme or the absence of its activity in individual organs and serum, regardless of the fish habitat location. The Pleuronectiformes demonstrated diversity in content and distribution of lysozyme in the body of various fish species. Two plaice species with the unique distribution inhabiting the Sea of Okhotsk were found. This feature is due, first, to the highest lysozyme content in serum of the previously studied fish; second, to the 2-3-fold excess of the enzyme content in serum as compared with the studied immunocompetent organs. The obtained results confirm the opinion about the existence of various related groups among fishes which essentially differ in the lysozyme role in nonspecific immunity.

Aim: Study the effect of metabolites of H2O2-producing lactobacilli on enzymatic and bactericidal activity of lysozyme., Materials and Methods: 9 H2O2-producing vaginal lactobacilli, Micrococcus luteus NCTC 2665, Escherichia coli State Institute of Standardization and Control No 240367, Lactobacillus acidophilus Institute of Cellular and Intracellular Symbiosis No 37 were used. Ability of lactobacilli to produce H2O2 was evaluated by oxidation of tetramethylbenzidine by peroxidase. Lysozyme was modified by mixing with equal volumes of lactobacilli metabolites, metabolites of H2O2-producing vaginal lactobacilli previously treated with catalase were used in control. Lysozyme enzymatic activity was determined by speed of M. luteus lysis, bactericidal--by survivability of E. coli in Endo medium and L. acidophilus--in MRS medium., Results: Decrease of enzymatic activity of lysozyme due to its contact with H2O2-producing lactobacilli metabolites was detected. This effect is accompanied by growth of bactericidal activity of lysozyme against E. coli and decrease against L. acidophilus. The degree of changes of enzymatic and bactericidal activity of lysozyme by lactobacilli metabolites depended on concentration of hydrogen peroxide in them., Conclusion: Modification of lysozyme by H2O2-producing lactobacilli metabolites resulting in opposite changes of its activity against autochthonous and allchthonous bacteria is one of the mechanisms of formation of stable microbial biocenosis in human organism.

Aim: Determination of interconnection of genetic determinants of secreted lysozyme inhibitors with enterobacteria anti-lysozyme phenotype., Materials and Methods: 50 cultures of non-hemolytic Escherichia coli, Klebsiella pneumoniae isolated from feces of patients with stage I - II intestine dysbiosis and Salmonella enterica isolated from patients with acute intestinal infections (AII) and reconvalescent salmonella carriers served as material for the study. Isolation of matrix DNA of the studied strains for PCR was carried out by DNA-Express kit (Lytex Co., Russia). PCR screening of secreted lysozyme inhibitors genes ivyC and pli was performed based on Syntol Co. (Russia) primers and reagents. Amplicon detection was carried out by agarose gel electrophoresis method. Detection of general anti-lysozyme activity (ALA) was performed by plate method, secreted and sorption ALA components - photometrically by O.V. Bukharin et al. (1999) and V.Yu.Sokolov and A.P.Luda (1987) methods, respectively., Results: Screening of chromosome localization genes - ivyC in escherichiae and klebsiellae and pliC in salmonellae by PCR method showed their ubiquitous spread among the studied cultures. The search for homologues of pliC gene that are characteristic for K. pneumoniae virulence plasmid revealed positive result in 19 +/- 5.5% of cases. The lowest level of ALA wa noted in carriers of only ivyC gene accounting for an average of 2.8 +/- 0.6 microg/mlxOD, while all enterobacteria with pliC gene had average ALA value of 4 +/- 0.3 microg/mlxOD., Conclusion: Anti-lysozyme activity of enterobacteria is part of the general mechanism of microorganism lysozyme resistance and is determined by the presence of secreted lysozyme inhibitor genes. Application of molecular-genetic approach in the form of the developed experimental test-system based on PCR method allowed to detect secreted lysozyme inhibitor genes in screening mode. High level of secretory ALA is coupled with the presence of pliC gene, while in ivyC gene carriers lower values of the attribute were detected.

Mechanisms of resistance of bacteria genus Enterococcus to the most important factors of innate immunity of the host--antimicrobial proteins and peptides--are described in the review. Data on enterococci lysozyme resistance associated with modification of peptidoglycan and changes in the net charge of the bacterial cell surface are presented. The role of enterococci sigma-factor with extra cytoplasmic SigV function is described. Evidence on microbial activation/degradation of neutrophil alpha-defensin (HNP-1), antibacterial peptide LL-37, cecropin, beta-lysine (thrombocytic cationic peptide) is presented. The accumulated experimental material is discussed from the position of persistence of enterococci--both pathogens causing various infectious processes and commensals composing a part of normal host microflora.

C57Bl/6 mice were intranasally infected with influenza virus A/H5N1 A/goose/Krasnoozerskoye/627/05. The mortality rate of animals reached 70% on day 14 of the disease. The lungs of animals were characterized by necroses, destruction of vessels, hemorrhagic and thrombotic complications, edematous syndrome, and early fibrosis of the interstitium. On days 6-10 after infection, fibrosis was found in the zones of postnecrotic inflammatory infiltration. The expression of lysozyme and myeloperoxidase by pulmonary macrophages was initially increased, but decreased on day 10 of the study. The number of cathepsin D-expressing macrophages was elevated up to the 10th day of examination.

The effect of betulin derivatives on persistence properties of microorganisms was studied in vitro. It was shown that the antipersistence action of the betulin derivatives depended on their structure and the microbial species. The experimental data on the structure - function relation could be useful in development and synthesis of new agents for therapy of chronic infections associated with persistence of bacterial pathogens in macroorganism.

Enzymatic (the action of lysozyme) and chemical (hydrogen peroxide) hydrolysis of chitosans with various degree ofacetylation (DA)--25, 17, and 1.5%--was performed. Purification and fractioning of the hydrolysis products were performed using dialysis, ultrafiltration, and gel-penetrating chromatography Low-molecular (LM) derivatives of the polysaccharide with molecular masses from 17 to 2 kDa were obtained. The study of their antiviral activity against the tobacco mosaic virus (TMV) showed that these samples inhibited the formation of local necroses induced by the virus for 50-90%. The antiviral activity of the LM chitosans significantly increased with the lowering of their polymerization degree. Furthermore, the products of the enzymatic hydrolysis possessed higher activity than the chitosan samples obtained as a result of chemical hydrolysis. It was revealed that the exhibition of the antiviral activity weakly depended on the degree of acetylation of the samples.

The species composition, antilysozyme activity and antibiotic resistance of coryneform bacteria, isolated from the reproductive tract of women with microecological disturbances, were studied. Sixty six women without microecological disturbances and 102 female patients with microecological disturbances in the reproductive tract were examined. The study showed that Corynebacterium minutissimum, C. amycolatum, C. group JK, C. bovis and C. pseudodiphtheriticum prevailed in the healthy women. In the patients with microecological disturbances in the reproductive tract C. vitarumen, C. matruchotii, C. striatum, C. renale and C. urealyticum were detected in addition to the above species. The average antilysozyme activity of the coryneform bacteria isolated from the healthy women was 1.32 +/- 0.47. In the patients with microecological disturbances in the reproductive tract it was 1.84 +/- 0.38. The in vitro susceptibility of the coryneform bacteria to antimicrobial agents was determined. High prevalence of resistance to beta-lactams (oxacillin and penicillin), erythromycin and co-trimoxazole was detected. Thus, the species variety and the antilysozyme activity of the coryneform bacteria in the reproductive tract of the women with microecological disturbances were found to be higher. The high prevalence of resistance to oxacillin, penicillin, erythromycin and co-trimoxazole in the coryneform bacteria isolated from the patients with the microecological disturbances did not differ from that in the healthy women.

Aim: To substantiate the possibility to use the biological characteristics of microorganism, in particular, factors of its persistence, for assessment of severity of trophic ulcers of lower extremities., Materials and Methods: Clinical examinations and bacteriological tests of 48 patients aged from 37 to 80 years with trophic ulcer of lower limbs were performed. Antilysozyme, anticomplement, anticarnosine as well as hemolytic activity of isolated microorganisms were assessed., Results: It was established that microflora of trophic ulcers of lower limbs are diverse and microorganisms were isolated both in monoculture and in associations, with maximal significance of Staphylococcus aureus. Analysis of biological properties of microflora isolated in patients with various courses of trophic ulcers of lower limbs allowed to determine roles of antilysozyme, anticomplement, anticarnosine and hemolytic activities in severity of the illness., Conclusion: Performed studies allowed to develop diagnostic models for prediction of severity course of trophic ulcers of lower limbs.

Aim: To study dynamics of species composition, factors of pathogenicity and persistence, index of microbial load by bacteria translocating to tympanic cavity from nasal cavity., Materials and Methods: Translocation of bacteria was reproduced on the model of experimental staphylococcal purulent otitis media in 22 adult rabbits from "chinchilla" breed. Identification of translocating strains was performed by radioisotope label. Microflora of nasopharynx and middle ear was studied on day 4, 6, 10, 20, 30, and 180 after inoculation., Results: Translocating strains differed from nontranslocating by higher level of antilysozyme activity (> or =3 mcg/ml) and higher proportion of their microbial load in total index of microbial load of source biotope (> or =5%). During unfavorable course of otitis, increase of pathogenicity of strains-translocants in circumstances of microbial interaction was observed., Conclusion: One of the mechanisms for the development of otitis media is translocation of indigenous bacteria and their associates to the inflammation site in middle ear where microbial interactions determine the outcome of infection. Results of experimental studies allowed to develop the method for prediction of otitis media course.

Aim: To study mechanisms of survival and regulation of natural algobacterial associations., Materials and Methods: Lysozyme, antilysozyme, catalase and antagonistic activity as well as hydrogen peroxide production were determined in algobacterial associations formed by green algae or cyanobacteria and satellite bacteria. For assessment of reactions of microbial interactions, derivates of Escherichia coli, which differ on the presence of antilysozyme and catalase signs, were used., Results: Multidirectional effects of symbionts in biocenosis were revealed. Involvement of functional systems lysozyme-antilysozyme and hydrogen peroxide-catalase in regulation of associative interactions in algae-bacterial biocenosis was established. In conditions of antibacterial action of algae's hydrogen peroxide, catalase activity of associate bacteria provides survival of microorganisms in association with algae, whereas high level of catalase activity promotes domination of associate bacteria in algobacterial communities. Antagonistic activity allows the microalgae to suppress growth of undesirable microorganisms and regulate their number in algobacterial cenosis., Conclusion: Functional systems lysozyme-antilysozyme, hydrogen peroxide-catalase as well as antagonistic activity of symbionts form the basis for regulation of symbiotic interactions in associations of water microorganisms, which has ecological and sanitary-hygienic implications.

Aim: To determine features of species composition and factors of persistence of bifidobacteria of human gut microflora in healthy state and during dysbiosis., Materials and Methods: Strains of bifidobacteria isolated from feces of patients with gut dysbiosis grades I - III (24 participants) and conditionally healthy persons (14 participants) were used for the study. Isolation and identification of microorganisms were performed by conventional methods. Antilysozyme activity was determined by photometric method and antilactoferrin sign--by immunoenzyme assay., Results: Bifidobacteria isolated from intestinal biotope have differences in species composition, which depended from age and state of microbiocenosis of studied persons. Bifidobacterium bifidum was dominated between strains of bifidobacteria isolated from infants with eubiosis, whereas B. longum dominated in persons > 1 y.o. B. bifidum and B. adolescentis were mainly isolated in infants with gut dysbiosis, where as in children > 1 y.o. B. adolescentis was predominantly isolated. New characteristic of bifidoflora--antilactoferrin activity--was discovered for the first time. Expression of this sign, as well as antilysozyme activity, varied and depended from species of bifidobacteria., Conclusion: Obtained data widen our views on species composition of bifidobacteria and discover possible mechanisms of persistence of these microorganisms in intestinal biotope associated with inactivation of host defense factors--lysozyme and lactoferrin.

Comparison of Pseudomonas putida group of phages attributed to five species (af, phi15, phi27, phi2F, and pf16) with their common property of halo-formation (formation of lightening zones) around phage plaques was conducted. The halo around phage plaques appears as a result of reduction or disappearance of bacterial polysaccharide capsules. The concentration of viable bacteria remains unchanged within the halo. A comparison of specificities of halo-formation products from various phages was conducted by a simple method. These products were shown to be highly specific and inactive on other species of pseudomonads. Phage-resistant P. putida mutants scored with respect to various phages, which lost phage adsorption ability, were tolerant to the effect of halo-formation products in most cases. Apparently, the capsular polysaccharides, which serve as a substrate for depolymerases and are the primary phage receptors, may be often lost. Results of partial sequencing of the af phage genome revealed an open reading frame that encodes the enzyme transglycosylase similar rather to transglycosylases of oligotrophic bacteria belonging to different species than to lysozymes of other phages. Possibly, it is a polyfunctional enzyme combining functions of lysozyme and an enzyme that executes the penetration of phage particle across extracellular slime and capsule.

Microbial contamination of the upper airway mucosa and skin was quantified and the salivary concentrations of lysozyme and secretory immunoglobulin A were determined in persons exposed to toxic substances. The antagonistic activity of the intestinal microflora was studied in firemen. Lower resistance was revealed in firemen and gas rescuers upon exposure to poor factors during their activity.

There was studied the dependence of hard dental tissues resistance upon general and ionized calcium concentration, activity of alkaline phosphatase responsible for inorganic compounds phosphate removal. Hard dental tissues resistance depended upon lysozyme content in saliva. According to the results received the general and ionized calcium content in all species of mixed saliva raised to the normal values during the study execution. The alkaline phosphatase activity was reduced and lysozyme content was raised. Oral hygiene index in tested subjects was equal to 1.2+/-0.03 and DMF=12.0+/-0.3 before the study beginning; after the study DMF index did not change as well as its component D (3%) that could be interpreted that during 1 year test period carious activity in vegetarians did not change. During examination at the site of active caries pigmented substitutive dentin was detected that testified to the process development stoppage.

Aim: To investigate the modifying effect of hexylresorcinol chemical analog on anti-lysozyme activity of bacteria., Materials and Methods: Influence of hexylresorcinol on anti-lysozyme activity (ALA) of bacteriawas studied on the examples of such strains as Bacillus cereus 279, Klebsiella pneumoniae 278, Escherichia coli 101, which are able to inactivate lysozyme. As a chemical analog of microbial regulators, C6-alkyloxybenzol (C6-AOB) was used, which was introduced in growth medium containing microorganisms, which than were cultivated until entering in the stationary growth phase. Isolation of clones was carried out by seeding the 24-hours broth culture on solid growth medium followed by measurement of ALA with photometric method., Results: Modifying effect of chemical analog of extracellular microbial regulators (C6-AOB) on population structure of bacteria on the sign of anti-lysozyme activity was revealed. Maximal effect was observed at C6-AOB concentrations 1 and 10 mcg/ml. Clonal redistribution on ALA manifested by decrease of proportion of clones with high and intermediate values of ALA and increase of proportion of clones with low ALA or its absence., Conclusion: Obtained data are perspective for development of measures for control of persisting pathogenic microorganisms by modification of persistence factors with microbial autoregulators.

Aim: Effects of sublethal concentration of active forms of oxygen (hydrogen peroxide and hydroxyl radical) on cell surface properties of Escherichia coil, Staphylococcus aureus, Bacillus subtilis, and Klebsiella pneumoniae were studied., Materials and Methods: Hydrophobicity of cell surface measured by transition of cells from water phase to hydrocarbomic phase and by the ability of bacteria to sorb lysozyme and hemoglobin., Results: Treating of bacterial cells with hydroxyl radicals compared with hydrogen peroxide resulted in more marked decrease of bacteria's hydrophobicity and reduction of their ability to sorb on the surface the lysozyme and hemoglobin. Increasing of the number of R-forms in the bacterial population after contact with hydroxyl radicals was revealed., Conclusion: Active forms of oxygen generated in biological systems in concentrations which are not lethal for majority of microorganisms can regulate prokaryote and eukaryote interactions by changing their surface characteristics and therefore they are an ecologic factor determining forming and existence of microbial cenoses.

Aim: To determine a composition of gut microflora during salmonellosis and to study the modification of persistent characteristics (antilysozyme activity, ALA) of symbiotic microorganisms in associations., Materials and Methods: Bacteriologic study of feces was performed in 90 patients aged 18-39 years, which were divided to three groups: patients with salmonellosis in acute phase, reconvalescent patients, and conditionally healthy persons. Condition of gut microflorawas determined; microorganisms associated with Salmonella infection were isolated, and their influence on ALA of Salmonella was studied., Results: Gut microbiocenosis was more diverse in patients compared with healthy persons. Significant reduction of bifidobacteria quantity (to 10(7) CFU/g of feces and less), especially in reconvalescent period, was noted. Association between bifidoflora deficiency and excessive increase of quantity of yeast fungi was revealed. It was determined that exometabolites of indigenous anaerobic microflora (bifidobacteria) promoted decrease of ALA of Salmonella, whereas opportunistic facultatively anaerobic microorganisms (enterobacteria, staphylococci) rendered mainly stimulating effect on the ALA of Salmonella., Conclusion: Obtained data reveal characteristics of bacterial interactions in associative symbiosis and provide insights about mechanisms of formation of pathobiocenosis and state of bacterial carriage.

Aim: To determine daily dynamics of antibacterial resistance as well as antilysozyme and coagulase activity of S. aureus strains., Materials and Methods: On an example of clinical strains of S.aureus isolated from patients with surgical infections daily dynamics of biological characteristics of staphylococci was studied. After 12 hours of incubation strains were tested for coagulase activity by standard method (test tube method), antilysozyme activity by photometric method, and antibacterial resistance by method of serial dilutions in agar. Tests were repeated each 3-hours during a day., Results: Variation of levels of studied biological characteristics of staphylococci during a day was revealed. Structures of coagulase and antilysozyme circadian rhythms had some differences in different S. aureus strains. Alongside with it, similarity in temporal expression of such biological characteristics of staphylococci as antibacterial resistance and antilysozyme activity was noted., Conclusion: Obtained data open prospect to use biorhythmological approach in study of biological characteristics of microorganisms during evaluation of their mechanisms of adaptation to changing environmental conditions. Chronobiological approach allows to reveal periods of maximal expression of S. aureus characteristics that could be used for increasing of effectiveness of antibacterial treatment by the choice of optimal time for administration of antibiotic.

Modifying action of C7-alkyloxybenzol (methylresorcin) on the antilysozyme activity (ALA) of opportunistic microorganisms (Bacillus cereus, Klebsiella pneumoniae, and Escherichia coli) was studied. C7-alkyloxybenzol (C7-AOB, methylrezorcin), which was used as chemical analogue of microbial autoregulators, was added to growth medium containing microorganisms, which were cultivated until entered stationary phase. Isolation of clones was performed by seeding of 24-hours broth culture on solid growth medium, and then ALA was measured using photometric method. Modifying action of C7-AOB on ALA characteristic-based population structure of B.cereus, K. pneumoniae, and E. coli was revealed. Maximal effect was detected when the concentration of C7-AOB was in range 1-10 mcg/ml. Decrease of mean ALA level caused by C7-AOB was linked to decrease of proportion of clones with high and intermediate ALA level, increase of proportion of clones with low level of lysozyme inhibitor, and emergence of clones lacking ALA in the population.

In order to determine the influence of combined use of ciprofloxacin and oxytocin on susceptibility of microflora to antibiotics as well as level of microbial anti-lysozyme (ALA) and anti-complement activity (ACA) 148 anaerobic and aerobic microorganisms were isolated from 80 patients with purulent infections of soft tissues. Susceptibility of staphylococci, streptococci, and enterobacteria to the most commonly used antibiotics was assessed by agar-diffusion method with standard disks. ALA and ACA of the isolated strains were defined by routine methods. Minimal inhibitory concentration (MIC) of ciprofloxacin and oxytocin for isolated pathogens were determined according to standards of NCCLS. Influence of oxytocin on MIC of ciprofloxacin was determined as well as inhibitory effect of the latter on factors of bacterial persistence. Decrease of MIC of ciprofloxacin as well as increase of its inhibitory effect on pathogens' ALA and ACA when it used in combination with oxytocin were noted. Usefulness of combined use of ciprofloxacin and oxytocin for treatment of different infections has been proposed.

The study established that aquatic plants differently affected the development of ascarid eggs. Some species of algae exerted a damaging effect on ascarid eggs only at early stages of embryogenesis while others did at its late stages, but some species did not produce any noticeable effect on the development of the eggs. A great difference was found in the development of ascarid eggs in different seasons. Gas exchange conditions were ascertained to affect the development of ascarid eggs. Analysis of the effect of egg lysozyme versus mollusk one on ascarid embryogenesis demonstrated that the latter had a more pronounced antiparasitic activity.

We studied efficacy of using intensive physical conditioning as prophylaxis of respiratory diseases in young children and health status of children exposed to physical conditioning in childhood (a total of 44 children aged from 1.5 months to 1 year; 58 children aged from 2.5 to 13.5 years). The proposed method of conditioning significantly diminished incidence of respiratory infections, enhanced local immunity of the upper respiratory tract and prevented development of chronic diseases at later age.

The patterns of persistence and virulence factors expression in the representatives of human microbial biocenosis depends on a complex of the environmental conditions: influence of microbes-symbionts, biotope peculiarities, properties of microorganisms located within eukaryotes. Interactions of symbionts in pairs "indigen-indigen" isolated from mucous membrane of tonsils in healthy persons, did not lead to changes in expression of pathogenic properties. Interinfluence in pairs "pathogen-indigen" and "indigen-indigen", isolated from patients with chronic tonsilitis were accompanied by an increase of anti-lysozyme, hemolytic and lecithovitellase activities. Migration of strains of non-enzymatized gram-negative bacteria (NEYNB) from nasal into tympanic cavity in experimental acute purulent otitis is connected with an earlier increase of their number in the nasal cavity and the expression of anti-lysozyme activity. In acute and chronic pyoderma, expression of ALA is more marked in bacteria from a perifocal damage in contrast to focal damage of normal skin. In conditions of interaction between erythrocytes and staphylococcal clones with different levels of expression of pathogenic factors, differences were observed in dynamics of hemolytic and anti-hemoglobin activities.

A total of 132 patients were examined for chronical endocervicitis by clinical, immunological and morphological methods. According to the results obtained the patients were subdivided into several groups. The first group covered 77 females with an active clinical somatic form of the disease. The second group included 55 patients with chronical inactive endocervicitis. Controls included 25 practically healthy females. No differences were found between immunological indices of peripheral blood in groups of patients with active and inactive forms of chronic endocervicitis. Immunological tests on cervical mucus in patients with chronic endocervicitis revealed differences in the total number of leukocytes, content of living cells, functional activity of neutrophils, concentration of immunoglobulins and proinflammatory cytokines. This study may contribute to the development of immunological criteria for diagnosis of inflammatory process activity as well as a diagnostic model.

Lysozyme is one of the most important factors of innate immunity, possessing anti-microbial action against a wide range of microorganisms due to cationic nature of protein and, in a lesser degree, due to muramidase activity. In the process of evolution, different mechanisms of lysozyme inhibition, defined as anti-lysozyme activity (ALA), were formed in microorganisms. The usage of the delayed antagonism principle allowed to reveal anti-lysozyme sign in microorganisms of different phylogenetic groups. In the review, data on the occurrence and level of anti-lysozyme activity in pathogens and representatives of normal microflora were presented; findings on nature and genetic determinants of lysozyme inhibitors are given. questions on drug regulation of ALA of the causative agents in infectious diseases and dysbiotic conditions are discussed.

The comparative study of adhesive, hemolytic, DNA-ase, lecithinase, antilysozymic, anticomplementary activities of mono- and associated cultures of 57 Enterobacter spp., 61 Citrobacter spp. and 55 Serratia spp. strains, isolated from patients with pyoinflammatory, intestinal and urological diseases is carried out. Different variations of cocultivated bacteria including Enterobacter and Citrobacter, Enterobacter and Serratia, Citrobacter and Serratia are used. It was shown, that cocultivated Enterobacter, Citrobacter and Serratia bacteria increased the persistent properties of mixt cultures.

In the study of 65 microbial cultures isolated from the purulent foci in acute pulmonary abscess and acute pyothorax of 48 patients, a wide spectrum of microflora was detected. Staphylococci and Pseudomonas prevailed among aerobes, bacteroids and peptostreptococci--among anaerobes. In cases of the prolonged course of the pathological process, as compared with the common one, microorganisms exhibited hemolytic activity and high antilysozyme and anticomplementary levels. These findings served as the basis for working out a mathematical model for the prognosis of the disease course with 95% probability.

Information on the properties of proteins of the macroglobulin family taking part in the host protection from viral, fungal and bacterial pathogens is reviewed. High plasticity and polyfunctional character of these proteins makes it possible to realize different protective functions. They inhibit the lysis of the cell wall by binding the hydrolases of the pathogen thus blocking its penetration into the cell, directly participate in the presentation of antigens to immunocompetent cells, transport antibacterial substances (interferons, lysozyme) to the zone of infection. In addition, macroglobulins take part in the apoptosis regulation in infected cells, utilization of the lysosomal enzymes of annihilated pathogens. The complexes of macroglobulins with some proteins are powerful inductors of antibody production. Further studies of the properties of these proteins will result in a better understanding of the nature of infectious process. The possibility of artificial formation of macroglobulin complexes with pathogen components or with substances possessing protective or anti-inflammatory properties opens prospects for using these proteins in the fields of vaccinology, gene therapy and molecular biology.

The study was made of therapeutic activity of silicon mineral water Tersinka inhalations on clinical symptoms, external respiration function and activity of inflammation in patients with chronic bronchitis and bronchial asthma as shown by biochemical markers of inflammation in the blood serum and nasal secretion. A correlation was found between treatment efficacy and concentration of sialic acids in the nasal secretion in pulmonological patients.

The effect of the synthetic immunomodulator polyoxydonium (PO) on some biological properties of pathogenic bacteria (Shigella flexneri, Salmonella enteritidis), opportunistic bacteria (Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacteroides fragilis, Peptostreptococcus anaerobius, Prevotella melaninogenica, Propionibacterium propionicum, Clostridium difficile) and fungi (Candida albicans), isolated during enteric infections, enteric dysbiosis, pyoinflammatory diseases, was evaluated in a number of in vitro experiments. The study revealed that the recommended therapeutic concentration of PO decreased antilysozyme activity (ALA) and the anticomplement activity in Klebsiella, Shigella, Propionibacterium, Clostridium, bacteroids, fungi of the genus Candida, but increased ALA in nonhemolytic Escherichia. Under the action of PO an increased sensitivity of the microorganisms under study to definite antibiotics of the lincosamide, fluoroquinolon, carbapenem and cephalosporin groups was noted. The data obtained in this study reveal one of the possible mechanisms of the corrective action of PO on the microbiocenosis of the intestine in dysbiosis, enteric infections and pyoinflammatory diseases.

The role of enzyme--substrate interactions for the survival of bacteria in natural biocenoses has been analyzed with the systems "lysozyme-antilysozyme", "histon-antihiston" used as models. The conception of a possible universal mechanism for supporting the circulation of pathogenic and opportunistic microorganisms among eukaryotes, irrespective of their evolutionary status and environment, has been formulated. This mechanism is ensured by the natural resistance of the eukaryotic cells and by persistence factors on the part of the pathogen; as a result, the dynamic system of interactions is formed which facilitates the survival of microorganisms due to their persistence potential. New knowledge thus obtained opens prospects in the study of sanitary and ecological aspects of water biocenoses.

In a number of in vitro experiments the effect of oxytocin on the antilysozyme and anticomplemental activity of Propiobacterium propionicum, Bacteroides fragilis, Prevotella melaninogenica and Peptostreprtococcus anaerobius, isolated from patients with acute pyoinflammatory pleuropulmonary diseases, was studied. Antibiotic resistance dynamics of the infective agents under study to lincomycin, clindamycin, thienam, vancomycin was also detected. The inhibiting activity of oxytocin on the persistence properties of B. fragilis, P. melanogenica and P. anaerobius was noted. Under the influence of the preparations used changes in the sensitivity of the strains to a number of antibiotics of the lincosamide, carbapenem and glycopeptide groups were found to occur. The data thus obtained were indicative of the possible mechanisms of action of oxytocin in the treatment of acute pyoinflammatory pleuropulmonary diseases of anaerobic nonclostridial etiology.

The effect of the duodenal contents and its components on the antilysozyme activity (ALA) of enterobacteria was studied. Under the action of native bile and the preparation of dried bile the stimulation of the expression of ALA factor in 86.6-93.3% of enterobacteria was observed. Pancreatin increased the level of the secretion of ALA factor by 50% in comparison with the control. The preparation of egg lysozyme produced no changes in the frequency and level of the expression of ALA factor. The study revealed the dose-dependant character of the action of duodenal contents: in the native form, as well as at concentrations of 50% and 25%, duodenal contents stimulated the expression of the ALA factor of enterobacteria; at concentrations of 12.5% and lower, its effect could be stimulating, inhibitory or neutral.

The species composition and biological properties of microflora isolated from 42 patients with acute inflammatory pulmonary and pleural diseases were studied. A wide spectrum of aerobic and anaerobic microorganisms was detected. Infective agents causing severe course of the infectious process were found to have a high level of persistence properties.

The biological properties of vaginal lactobacilli strains with different colonization capacity were studied. As revealed in this study, colonization depended on the characteristics of species, individual elements of intrageneric antagonism, adhesion, resistance to antibacterial factors and the capacity for producing lysozyme. These properties of lactobacilli ensured the possibility of their adaptation to the conditions of the environment, manifested by its bacterial contamination. The data obtained in this study may be used for the study of symbiotic relationships between nonpathogenic bacteria with the host organism.

Antilysozyme activity (ALA) as well as antibiotic resistance were detected in 133 microbial cultures isolated from bioptic specimens of the mucous membrane of the ulcerous and periulcerous zones, taken from patients with gastric and duodenal ulcer. In 85.7-94.7% of cases Gram positive cocci and in 62.5% of cases Gram-positive bacilli showed no ALA. 50% of Gram negative bacteria cultures lacked ALA, while the remaining 50% exhibited this activity, on the average, 2.36 +/- 1.40 mkg/ml. Lysozyme activity was determined in 33.3% of the isolated staphylococci strains both with and without ALA. Staphylococci isolated from the gastric mucosa of healthy controls had no ALA in 33.3% of cases, and in 66.7% of cases ALA was equal to 2 mkg/ml. Gram positive coccal microflora showed, mainly, high sensitivity to antibiotics. In Gram negative bacteria antibiotic resistance was determined in 44.3 +/- 21.2% of the isolates. In Gram negative microorganisms correlation between ALA and antibiotic resistance was observed. From the periulcerous zone of patients with gastric and duodenal ulcer persistence associated Gram negative microorganisms were mainly isolated.

Lysozyme and antilysozyme activities present in a wide range of microorganisms determine the so-called lysozyme-antilysozyme system of hydrobionts, which greatly contribute to the formation of aquatic biocenoses. However, the mechanism of the functioning of this system in natural freshwater communities remains obscure. The experimental investigation of lysozyme-antilysozyme interactions in a model Tetrahymena--Escherichia community showed that the antilysozyme activity of Escherichia coli leads to incomplete phagocytosis, thus enhancing bacterial survival in a mixed culture with infusoria. The selection and reproduction of bacterial cells resistant to grazing by infusoria determine the character of host-parasite interactions and allow bacteria to survive. It was demonstrated that the antilysozyme activity of microorganisms, which is responsible for bacterial persistency in natural biocenoses, is involved in the maintenance of protozoa-bacteria communities in bodies of water.

In experimental rheumatoid arthritis, certain indices for local defence of the lung were studied together with effects on these of preparations of vitamin E and thymalin. Noted in experimental rheumatoid arthritis are manifest changes in quantitative indices for cellular population of the bronchoalveolar space and disturbances in humoral mechanisms of defence of the lungs. The drugs employed for the treatment of the affliction have a positive effect on quantitative indices for the cell population of the lung local defence factors. But no significant effects could be demonstrated of thymalin on humoral factors of defence of the lungs. Unlike thymalin, tocopheroli acetas is noted to augment the secretion of lysozyme, to decrease the activity of phospholipase A2, to improve the surface-active properties of the lung surfactant. It is suggested that its antioxidant, membrane-stabilizing action may be responsible for the positive effect on indices for local defence of the lung.

The gene of microbial lysozyme (lyz) of S. aureus 118 and the gene of lysostaphin (lzf) of S. aureus RN 3239 were cloned and their expression in B. subtilis cells was shown. Lysozyme production in B. subtilis recombinant clone pLF14-Lyz, obtained as the result of cloning, was 2.5-fold greater than lysozyme production in S. aureus wild strain 118. Lysostaphin production in B. subtilis recombinant strain pLF14-Lzf which had inherited the cloned genes was approximately equal to lysostaphin production observed in S. aureus initial strain RN 3239. The production of lysozyme and lysostaphin in the cells of B. subtilis recombinant strains was observed at 30 degrees C and pH 5.5, while in S. aureus initial strains 118 and RN 3239 bacteria produced lysozyme and lysostaphin at 37 degrees C and pH 7.5 respectively.