Correlation of marker periodontopathogenic bacteria with the immune component sCD14 secretion level in inflammatory periodontal diseases.

Lipopolysaccharide of the cell wall of gram-negative bacteria is a highly active biological substance: its interaction with toll-like receptors-4 (TLR-4) of myeloid cells leads to the activation of a cascade of inflammatory reactions, which is accompanied by the release of the soluble CD14 receptor (sCD14), which can be considered not only as a marker of cell activation by endotoxin, but also as a marker of microbial translocation. The aim of the work was to assess the prognostic significance of the sCD14 level in the samples of the periodontal pocket in inflammatory periodontal diseases and the relationship of its secretion with marker periodontopathogens. For the study, washes were obtained from the periodontal pocket (88 samples in total) from patients with chronic periodontitis and intact periodontium. The sCD14 content was determined by ELISA; during real-time PCR, the marker periodontopathogens Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Treponema denticola, Porphyromonas gingivalis, Prevotella intermedia, and Candida albicans were isolated. The study revealed differences in the level of sCD14 secretion by groups: in chronic periodontitis, its content was 8,5 times higher than in the control group and amounted to 17,2±4,06 ng/ml (p=0,006). The frequency of detecting genes of periodontal pathogenic bacteria was 89,3% in patients with periodontitis and 31,25% in the group with intact periodontium. An interesting dependence of the detection of periodontal pathogenic bacteria in the group of patients with chronic periodontitis was established depending on the content of sCD14. Thus, at high concentrations of soluble coreceptor, a greater number of periodontopathogenic bacteria of the I and II orders were released. Thus, in inflammatory periodontal diseases, the processes of sCD14 synthesis change, which is probably due to the colonization of periodontal pathogenic bacteria and the action of their toxins and aggression factors. The relationship of marker periodontopathogens with the level of secretion of the immune component sCD14 and its effect on the structure of the periodontal index reflect shifts in the processes of reparative regeneration of the oral mucosa and the regulation of local immunity in response to microbial invasion.

Spectrum and resistance determinants of oral streptococci clinical isolates.

The profiles of oral streptococci sensitivity to antibacterial drugs may reflect information about the presence of macroorganism resistance determinants. The aim of the work was to isolate the spectrum of oral streptococci from the microbiota of the oral cavity of patients and to determine their sensitivity to a wide range of antibiotics. A total of 342 microbial streptococcal isolates were isolated from saliva samples and a periodontal pocket and tested for antibiotic sensitivity. Species identification of streptococci was carried out using biochemical API test systems. Evaluation of antibiotic resistance was performed using E-tests. Real-time PCR was used to identify the presence of tetracycline and macrolide resistance genes. The study identified six types of oral streptococci: S. oralis, S. salivarius, S. mitis, S. sanguinis, S. anginosus and S. mutans. All streptococci were sensitive to linezolid and meropenem. The proportion of penicillin-resistant streptococci in the subgroup S. oralis / mitis / mutans was 47,8% versus 23,5% in the subgroup S. salivarius / sanguinis / anginosus (p = 0.020). Significant levels of resistance were revealed to macrolides (erythromycin) - 47,9%, tetracyclines (tetracycline) - 44,4% and quinolones (ofloxacin) - 41%. Multiple drug resistance (MDR) was detected in 31,9% of oral streptococcal isolates, a combination of erythromycin, tetracycline and ofloxacin resistance was prevalent in 79 isolates (23,1%). The most common genotypes of macrolides and tetracycline resistant oral streptococci (in 127 streptococcal isolates with combined resistance) were ermB-mefE + and tetM + tetQ-, respectively. Thus, S. oralis / mitis / mutans group streptococci predominated in the structure of antibiotic-resistant oral streptococci, including MDR. So, being in one of the most densely populated biotopes of a macroorganism, oral streptococci can mediate the transfer of resistance determinants to more pathogenic and clinically significant microorganisms, which requires careful monitoring of their level of susceptibility to antimicrobial agents.

[Competence-oriented exam in clinical laboratory diagnostics for students studying in the specialty «Medical Biochemistry¼.]

In connection with the introduction of annexes and changes to the Federal State Educational Standard of Higher Education in the specialty 30.05.01 «Medical Biochemistry¼, a need arose to improve the assessment tool of general professional and professional competencies formation in the discipline - clinical laboratory diagnostics. A competence-oriented exam (COE) in the studied discipline is developed and implemented. Admission to the exam is the development of practical skills by students in the discipline modules, portfolio design and posting the results on the "Moodle" platform. COE includes two stages: testing to assess the level of theoretical knowledge deepening and solving a situational problem to assess the skills and abilities, interpret the results of laboratory tests and prepare a clinical and laboratory report. Situational tasks and checklists have been developed that make it possible to conduct an objective and comprehensive assessment of the competencies formed by students during the training process, which allows the graduate completed the program to solve professional problems.

[Influence of antibiotics on formation of microecology in premature children with low and extremely low body weight at birth].

AIM: Study the influence of antibiotic therapy on the formation of main biotope microflora nasopharynx, large intestine, urinary system) of the premature child organism weighing less than 500 g at birth in hospital. MATERIALS AND METHODS: Bacteriological study of upper respiratory tract discharge, urine, large intestine contents in 58 premature children during admission and discharge from newborn and premature children pathology department was carried out. Factor analysis method was applied to construct factor models of antibiotics influence on main biotope microbiocenosis formation. RESULTS: Deficiency of obligatory normal flora members in all the 3 biotopes was noted in all the children during admission to the department. Colonization of all the biotopes by obligatory members was noted by discharge, however the parameters do not reach age norm. Antibiotics therapy is the main factor, in all the biotopes opportunistic and pathogenic microorganisms prevail. CONCLUSION: The formation of main biotope microbiocenoses does not occur and carriage of pathogenic and opportunistic microorganisms is noted in premature children receiving massive antibiotic therapy.