Vol 94, No 4 (2017)

Aim. Study taxonomic belonging of collection strains of tularemia causative agent based on proteomic and molecular-genetic methods of identification. Materials and methods. 23 strains of tularemia were used in the study, isolated from Krasnoyarsk region and Altai Republic from 1950 to 2015. FT-agar was used for the cultivation. Spectra for time-of-flight mass-spectrometry were collected using Microflex LT (Bruker Daltonics, Germany) and analyzed compared with previously collected enhanced database of MALDI Biotyper 3.0. PC R with specific primers was carried out with electrophoretic visualization of results in real time. Results. F. tularensis strains isolated from south of western Siberia from 1950 to 2010 were established to belong to subspecies holarctica, and 56.3% of those - erythromycin sensitive (1 biovar Ery^s), the rest - erythromycin-resistant (II biovar Ery^R). 7 strains isolated after 2011 by citrulline ureidase activity, cleavage of glycerin and presence of pdpA and pdpD fragments of pathogenicity island (FP1) were determined as Central Asian subspecies. Conclusion. Results of a retrospective study of biological properties of tularensis strains isolated from south Siberia have shown the lack of Central Asian subspecies tularemia causative agent in the collection of Irkutsk Institute for Plague Control before 2011. Detection of this subspecies in Russian Federation gives evidence on the necessity to study and analyze problems of epidemiology, ecology and epizootology of Central Asian subspecies tularemia causative agent as well as determination of borders of its spread.

Aim. Study biodiversity, sensitivity/resistance to antibacterial preparation (ABP) of opportunistic microorganisms of Enterobacteriaceae family isolated from surface reservoirs of Rostov-on-Don in 2014 - 2016. Materials and methods. Determination of genus and species membership of enterobacteria was carried out by the results of a complex of biochemical tests using MALDI Biotyper program-apparatus unit. Sensitivity to ABP was determined by serial dilution method. Results. 468 strains of opportunistic and pathogenic enterobacteria were isolated during the study. 20 genera, 33 species of microorganisms were identified. (37.0%), Klebsiella (13.2%), Citrobacter (8.0%) predominated. 8.5% of the strains isolated in 2014 were sensitive to ABP, 5.2% - in 2015; strains sensitive to ABP were not detected in 2016. The number of polyresistant isolates has increased during the last 3 years: 40.7% strains in 2014,60.1 % in 2015. 80,0% in 2016. Ceftriaxone, gentamycin and ciprofloxacin had high activity against the isolated enterobacteria. The highest resistance was documented against ampicillin, nalidixic acid, nitro-furane, co-trimoxazole. Conclusion. The data obtained allow to evaluate the dynamics of increase of polyresistant strains of enterobacteria isolated from surface reservoirs.

Aim. Construction of test-systems for dot-immunoassay using colloid gold nanoparticles as a marker of specific antibodies for the detection of botulinic toxin in clinical material and food products. Materials and methods. 20 nm gold nanoparticles were used as a marker of specific antibodies. IgGs were isolated from polyvalent diagnostic sera against type А, В, С, E, F botulin toxins produced by SPC Allergen (Stavropol) with 5000 - 10 000 ME activity. Botulin toxin in clinical material (blood sera) from 3 patients with established botulism clinical diagnosis as well as food product (home-made mushroom soup solyanka) was determined by dot immunoassay on nitrocellulose membrane. Results. Botulin toxin was detected in all the studied samples (blood sera from 3 patients and the soup) that was registered in the patient No. 1 at the 1:2112 dilution of fhe studied sample, in patient No. 2 - 1:32, in patients No. 3 - 1:1056, in the food product - 1:8. Botulin toxin was not detected in the negative control (pure cultures of the dysentery cauzative agents and intestine yersinosis, blood sera of the patient with All and a healthy individual as well as canned beans in tomato sauce and canned green peas). Conclusion. A highly sensitive specific test-system was developed for dot-immunoassay based on the commercial anti-botulin antibodies labelled with colloid gold particles that allows to detect botulin toxins within 2 hours in the sample volume of 1 - 2 microlites .

Aim. Evaluate the effect of anti-phage humoral immune response on effectiveness of phage therapy of infections related to medical care (IRMC). Materials and methods. 42 patients on extended mechanical ventilation (MV) in neuroreanimation, 1 time in 2014, 4 times in 2015 and 1 time in 2016 had received bacteriophage cocktail per os - 20 ml including 6 patients - additionally 3-5 times. Effectiveness of phage therapy was evaluated by seeding of IRMC strains from samples of endotracheal aspirate, blood, urine and feces of patients before and after treatment. Results. 87.5% of samples from the patients initially had gram-negative pathogens (Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa). Effective sanation for the first episodes of phage therapy was confirmed in 54 - 62.5% of cases. Pharmacokinetic studies have indicated a systemic mechanism of action for enteral forms of bacteriophages. Repeated courses of phage therapy did not result in significant eradication of pathogens. Antiphage immunity after a single administration of the cocktail of bacteriophages with a certain strain composition was detected using ELISA by the presence of specific IgG titers in a range from 1/16 to 1/4096 (in patients not receiving the cocktail antibodies were not detected). Conclusion. Reduction of sanation effect of bacteriophage could be due to formation of anti-phage antibodies after a repeated course in the same patient. Changes of strain composition of phage cocktail of bacteriophages is necessary to preserve results of phage therapy.

Aim. Study the prevalence of diarrhea-genic E. coli of the enteroaggregative group in children with intestine dysbiosis. Materials and methods. PCR method was used to study virulence factors in 511 strains of E. coli isolated during bacteriologic study of feces samples from 393 children aged less than 2 years. Sensitivity to antibiotics was determined by disc-diffusion method, results interpretation - according to clinical recommendations Determination of sensitivity of microorganisms to antimicrobial preparations, 2015. Results. 23 enteroaggregative E. coli strains were identified (EAggEC). All the strains had aaf gene coding aggregative-adhesion fimbriae and 4 other genes (aggR, ast, aap, aatA) in various combinations coding virulence factors EAggEC. 19 strains (87%) were not sensitive to antimicrobial preparations. Resistance to extended spectrum cephalosporins was determined by the production of extended spectrum beta-lactamase (ESBL) of CTX-M genetic family and AmpC cephalosporinase. Conclusion. Results of the study have shown that 6% of children with intestine dysbiosis are EAggEC carriers, that gives evidence on the necessity of detection of EAggEC strains - a novel group of diarrhea-genic E. coli not only in patients with diarrhea syndrome, but also using intestine dysbiosis.

Aim. Study the role of herpes viruses and pneumocystis in infectious complications in children from HIV-infected mothers. Materials and methods. Sera and blood cells from 59 children from HIV-infected mothers were studied for the presence of various markers of herpes virus infections and pneumocystosis by a complex of methods of modem laboratory diagnostics. Results. Frequency of detection of markers of herpes virus infection was from 10% for chicken pox in children with non-final HIV test to 93% for herpes simplex virus in HIV-infected children from closed organized groups. Signs of active infection in children with laboratory confirmed HIV infection were diagnosed 2.5 times more frequently for HSV infection and chicken pox and 1.8 times more frequently for HHV-6 and pneumocystis than in children with non-final HIV test. Markers of various disease stages with opportunistic infections (01) were detected in children with confirmed HIV-infection: primary acute and latent forms of the infection, reactivation, reconvalescence, whereas in children with non-final HIV test maternal antibodies against herpes virus and pneumocystis predominated. Markers of active infections excluding HSV and HHV-6 were more frequently detected in children from families than in children from closed organized groups. Conclusion. The feature detected - a lower percentage of detection of markers of active forms of 01 in HI V-infected children from social institutions - is determined by the fact that observation of these children is carried out by medical personnel that have the knowledge and experience of prophylaxis of infectious complications in HIV-infected children, whereas quality anti-epidemic regimen is frequently not maintained regarding home children with HIV infection. Another factor facilitating spread of opportunistic infections is the asocial lifestyle of most of the examined families. These data dictate the necessity of enhancement of anti-epidemic regimen and prophylaxis of opportunistic infections in family loci. Not only HIV-infected children, but also all the family members should be examined for markers of herpes virus infection and pneumocystosis in order to detect sources of the infection and timely execution of the prophylaxis measures.

Never before has the world community were not so close to the goal - poliomyelitis eradication. In 2016, the world recorded only 37 cases in the three endemic countries: Pakistan, Afghanistan and Nigeria. Despite the great progress in the final stages of poliomyelitis eradication have problems: the emergence and circulation of vaccine-derived poliovirus and related diseases, vaccine-associated paralytic poliomyelitis, social and political factors affecting of vaccination.

Despite long and successful use of Haemophilus influenzae b (Hib) vaccine, production of the vaccine against non-typed strains of Haemophilus influenzae (NTHi) is only being developed. Difficulties of this work are determined by features of NTHi compared with Hib: lack of polysaccharide capsule, high level of antigenic heterogeneity and specialties of pathogenesis development that includes spread through the organism from mucosa of the respiratory tract. Currently, 15 surface structures of NTHi are being actively studied with the aim of creating the vaccine. PE, P2, P6, PD proteins, outer membrane vesicles (OMVs) and others are among them. Only PD protein currently has practical application, that was used as a carrier with antigenic function in conjugated polysaccharide vaccines against pneumonia (Prevenar; PHiD-CV). Vaccination with these preparations allowed to reduce the total morbidity with acute rhinitis on children by 33 - 52%. However, this result can not be examined as final, thus, research and approbation of the vaccine-candidates continues.

Community-acquired pneumonia (CAP) has been one the most pressing issues of healthcare due to high morbidity and mortality that are stable. Analysis of literature shows similar trends in the character of immune response of patients with CAP, precisely - formation of immune response via humoral route (Th2) with suppression of cell immune response (Thl), whereas lack of cellular and humoral mechanisms of immunity and dysbalanced cytokine portion determine severity of the infection course. Inclusion of immune modulators into traditional therapy allows to enhance the response to the therapy already being administered. One of the national immune modulators is azoximer bromide (polyoxidonium), its administration allows to reduce the length and severity of the disease, as well as reduce the frequency of development of prolonged forms. Also, immune modulators of bacterial origin have received special interest as of late, and antibacterial therapeutic vaccines are being constructed based on them. Immunovac VP-4 polycomponent vaccine is distinguishable among the national preparations. Clinical-immunological effect of the vaccine has been studied in recent years on different pathologies and methods of administration in adults and children. Features of Immunovac VP-4 effect confirm the primary character of alterations in the immune system, that is the background of a certain pathology and is the reason for inclusion of immune modulating preparations into basic therapy of the diseases.