Immunosupressive activity of opportunist pathogens of the infectious-inflammatory process in the urinary tract of men with calculous pyelonephritis

Objective - identification of pathogens of the infectious-inflammatory process of the urinary tract in men with calculous pyelonephritis, antilysozyme, anticomplementary, anti-immunoglobulin activity and inhibitory effect on the phagocytic activity of peripheral blood neutrophils.Material and methods. 34 strains of opportunistic taxa were isolated and identified by bacteriological method from 30 sick men aged 31 to 65 years (mean age 48.8 ± 4.27 years). These bacteria have antilysozyme, anti-complementary and anti-immunoglobulin activity, as well as the suppressive effect of supernatants of cultures of calculous pyelonephritis pathogens on the phagocytic activity of neutrophils in the peripheral blood of patients. The determination of the anti-complementary activity of bacteria was carried out using the principle, which includes testing the protective action of bacteria and their metabolic products against the growth of an indicator strain in the presence of a bactericidal substance (complement of blood serum). The antilysozyme activity of pathogens was investigated by a photometric method. Anti-immunoglobulin activity was studied by the method described in the work of I.S. Gaidash et al. Results. The majority of 27 (79.41%) isolated strains of Enterobacteriaceae (84%) and facultative anaerobic and aerobic gram-positive cocci (E. faecalis, S.saprophyticus) (66.67%) exhibit antilysozyme activity of varying degrees. The highest antilysozyme activity was found in the isolated strains of K. pneumoniae, 8.14% lower – in E. coli. Most (64.71%) of isolated strains of Enterobacteriaceae (68%) and gram-positive cocci (55.56%) from the urinary tract of men with calculous pyelonephritis exhibit anti-complementary activity. All isolated and identified taxa exhibit inhibitory activity against immunoglobulins of the main classes: Ig M, Ig G, and Ig A. K.pneumoniae inhibits immunoglobulins of all major classes, the concentration of Ig M decreases under the influence of this taxon by 22.36%, Ig G - by 26.88% and Ig A - by 19.61%.Conclusions. Opportunistic pathogens (E. coli, K. pneumoniae, P. mirabilis, E. cloaceae, S. marcescens, E. faecalis, S. saprophyticus) of the infectious-inflammatory process of the urinary tract in men with calculous pyelonephritis exhibit different levels of antilysozyme, anti-complementary activity; reduce the function of immunoglobulins Ig G (by 21.60%), Ig A (by 21.49%) and Ig M (by 14.30%), inhibit the phagocytic activity of neutrophilsby 15.74%, their capturing ability- by 22.59%.

Antibiotic Sensitivity and Antilysozyme Activity of Staphylococcus aureus Strains Isolated from the Blood of Patients with Sepsis

Effective antibiotic therapy requires reliable data on the dynamics of sensitivity changes in each region. The aim of the study was to determine the sensitivity to antibiotics and antilysozyme activity of Staphylococcus aureus strains isolated from the blood of patients with sepsis over the period from 2017 to 2019. An increase in the resistance of Staphylococcus aureus to ceftriaxone, cefixime vancomycin, azithromycin, and levofloxacin was noted. Given the high incidence of resistance, the use of these drugs should be limited. Ceftazidime, tigecycline, daptomycin, and linezolid can be considered drugs of choice in empiric therapy of septic diseases of staphylococcal etiology. Most of the isolated strains exhibited antilysozyme activity (ALA). Most commonly the cultures had medium to high ALA scores.

BIOPROFILE OF MICROORGANISMS ISOLATED FROM URINE OF CATS WITH DISEASES OF URINARY SYSTEM

The research aim: to study the bioprophiles of microorganisms isolated from the urine of cats in the pathology of the urinary system (cystitis and urolithiasis). 46 strains of different types of bacteria were isolated from the urine of 34 sick animals by bacteriological method and identified using the biochemical test systems “Lachema” (“Erba Lachema s.r.o.”, European Union). The photometric method was used to determine the anti-lysozyme and anti-hemoglobin activity, the adhesion index, and the ability to form biofilms in isolates. It was established that microorganisms isolated from urolithiasis in cats were more often isolated in associations than microorganisms isolated from cystitis, among which monocultures prevailed. Biological properties of isolated microorganisms were studied, bioprofile were identified characterizing the strains. It is shown that cultures of S. aureus, E. coli, S. epidermidis from urine with urolithiasis was significantly higher values antigemoglobin activity; in E. coli – antilysozyme activity, in S. aureus – increased adhesion, in S. epidermidis – the ability to form biofilms than in urine strains with cystitis. P. aeruginosa strains isolated from urine with cystitis were characterized by a high level of adhesion compared to cultures of this species isolated from urine with urolithiasis. The results obtained can be used for differentiation of strains that can cause studied pathologies, as well as for selection of adequate therapy under the control of studied biological properties of microorganisms.

Microbiological monitoring of opportunistic Enterobacteriaceae of the Lena river

The aim is the study of the circulation, biological activity, persistent potential and genotypic characteristics of opportunistic Enterobacteriaceae of microbial community of the Lena River which is the one of the largest sources of water in Russia and Siberia. Gram-negative component of microbial community in the Lena River was mainly represented by Enterobacteriaceae (80%), including dominated Escherichia (dominant class) and Enterobacter and Klebsiella (subdominant class). In conditions of anthropogenic pollution there is a reorganization of microbial community of the Lena River in the direction of the increase in the proportion of opportunistic pathogens, their species diversity; there is a change of the biological activity of microorganisms, gains of share of strains characterized by antilysozyme activity, hemolytic activity, production DNase, phosphatase. The parameters of system “lysozyme-antilysozyme” are changing, the frequency of the occurrence of bacteria with antilysozyme activity is increasing. This shows the restructurization of the microbial community of water objects. Microorganisms of water objects in territories of anthropogenic pollution are characterized by multiple antibiotic resistance. The proportion of gram-negative opportunistic Enterobacteriaceae in microbial communities of water ecosystems determines the potential danger of water objects and the impact on the level of antibiotic resistance of bacteria. Opportunistic Enterobacteriaceae of microbial community of the Lena River near the city of Yakutsk are characterized by the presence of genetic determinants of pathogenicity (hlyA and sfaG). This is indicative of their potential epidemiological relevance. Microorganisms with high biological activity are markers of their epidemiological danger.

RESEARCH OF CERTAIN PATHOGENIC CHARACTERISTICS OF CLINICAL ISOLATES OF STAPHYLOCOCCI OF SKIN BIOME

A serious problem in patients with atopic dermatitis (AD) is the frequent attachment of a secondary skin infection. Among the microbes colonizing the skin of patients suffering from AD, S. aureus takes the lead. According to different authors, from the skin of 80–95 % of patients are sown Staphylococcus aureus. The survival of bacteria in a biotope is promoted by the persistent properties of microorganisms. Aim of the research: to determine the adhesive properties and antilysozyme activity of clinical strains of staphylococci isolated from the skin of patients with allergic dermatosis. The study included 50 patients with atopic dermatitis and 20 practically healthy individuals, from which 140 laboratory strains of staphylococci were isolated: 101 strains from patients with AD and 39 control strains. Bacteriological studies to isolate microorganisms and determine a number of pathogenic characteristics were carried out using the methods of classical bacteriology. The severity of antilysozyme activity (ALA) and adhesive properties of strains isolated from affected areas of the skin was significantly higher than in cultures isolated from intact skin areas, both qualitatively and quantitatively. The obtained data made it possible to assume a certain complicating role of these factors on the course of AD.

INTERMICROBIAL «SELF-NON-SELF» DISCRIMINATION IN «DOMINANT-ASSO-CIANT» PAIR OF PROBIOTIC STRAINS OF ESCHERICHIA COLI M-17 AND E.COLI LEGM-18

Aim. To use earlier developed method of intermicrobial «self-non-self» discrimination in «dominant-associant» pair for the assessment of foreignness of probiotic cultures of Escherichia coli M-17 (with pathogenicity island) and E. coli LEGM-18 (without pathogenicity island). Materials and methods. As dominants reference and clinical strains of bifidobacteria were used in the work, cultures of E. coli M-17 and E. coli LEGM-18 were taken as associants, differing in the presence of genes which code colibactin. Detection of the phenomenon of microbial discrimination was conducted according to the developed algorithm (Bukharin O.V., Perunova N.B., 2011) based on the principle of metabolite induction as a result of preliminary coincubation of dominants (bifidobacteria) with supernatant of associants and the formation of feed back in «dominant-as-sociant» pair. Special growth properties, biofilm formation, and antilysozyme activity served as biological characteristics of investigated coliform bacteria. Results. Testing of E. coli M -17 culture revealed depression of biological properties under investigation and it was estimated as «non-self» possibly due to the presence of pathogenicity island whereas E. coli LEGM-18 (without this fragment) sharply strengthened its biological characteristics and was subjected to assessment as «self». Conclusion. Use of intermicrobial «self-non-self» discrimination in «dominant-associant» pair is promising as basic method when selecting probiotic strains and cultures for creation of new symbiotic compositions and is suitable for quality control of probiotic products.