Microscopy of the stained slides revealed that the biofilm has a layered structure. In each image obtained using a video eyepiece, it was possible to differentiate 4 layers. From the border of the two media to the inside the fragmentation layer, the dense layer, the matrix substance layer, and the last one - the persistence layer. Channels of different diameters (from 10 to 24 microns) are observed across the entire thickness of the biofilm. Thus, used approach allows us to visualize and evaluate the structure of microbial biofilm, measure the thickness of layers and channel diameters. In addition, this method can be used to study the effect of antimicrobial drugs on bacterial films.The expression of toll-like and adhesive receptors on epithelial cells of the oral mucosa changes in different pathological conditions, both local and systemic levels, in particular, in chronic periodontitis. The long-term presence of periodontal pathogenic microorganisms in the gingival furrow stimulates and supports the inflammatory process. The interaction of periodontal pathogens with epithelial cells of the oral mucosa is the first stage of the development of periodontitis. The pathological process affects the function of epithelial cells, in particular their ability to interact with representatives of microbiocenosis. Therefore, the natural colonization of normal oral microbiota on buccal epitheliocytes, reflecting the ability of epithelial cells to microbial adhesion, is a sensitive indicator of various destabilizing processes. Determining the level of expression of toll-like TLR2 and TLR4 receptors on epithelial cells also allows us to assess the functional state of cells and the severity of the inflan assessing the severity of the inflammatory process in chronic periodontitis than determining the level of natural colonization.Recent studies have shown that bacterial resistance existed long before antimicrobials were used in medicine, and not only pathogens are resistant to antibiotics. 511 strains of E. coli isolated from the intestinal microbiota of children aged 1 month to 17 years living in St. Petersburg were studied the susceptibility to 15 antibiotics was determined by the disk diffusion method, as well as the susceptibility to 6 commercial bacteriophages produced by «Microgen» (Russia). The b-lactamase genes of molecular families TEM, SHV, OXA, and CTX-M were detected by multiplex PCR. 39,3% E. coli isolates were resistant to one or more antimicrobial classes. The proportion of multidrug resistant isolates (resistant to 3 or more classes) was 16,6%. Multidrug resistance to clinically significant antimicrobial classes (extended-spectrum cephalosporins (ESC) + fluoroquinolones + aminoglycosides) was detected in 0,8% isolates. Resistance to aminopenicillins was detected in 29,5%, ESC - 11,2%, fluoroquinolones - 13,3%, tetracycline - 20,0%, chloramphenicol - 9,8%, aminoglycosides - 2,5% isolates. b-lactam resistance was due to the beta-lactamase production to ampicillin - the molecular family TEM (81,9%), ESC - the CTX-M molecular family (87,7%) CTX-M1 - (66%) and CTX-M9 groups (34%). 43,5% multidrug resistant E. coli isolates were susceptible to at least one of the six commercial bacteriophages produced by «Microgen». The study showed that the intestinal microbiota of children is an important reservoir of E. coli resistant (including multidrug resistance) to various classes of antibiotics, and bacteriophage therapy is an alternative method for eradication of antibiotic-resistant E. coli.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. https://www.selleckchem.com/products/17-AAG(Geldanamycin).html The proportion of penicillin-resistant streptococci in the subgroup S. oralis / mitis / mutans l of susceptibility to antimicrobial agents.Intrauterine infections - infectious diseases in which infection of the fetus occurred in the ante- or intrapartum period, accompanied by clinical manifestations. The purpose of this study was to study the information content and diagnostic significance of the microbiological research method for the etiological diagnosis of intrauterine infections of a bacterial nature. A retrospective (2011-2014) and prospective (2015-2019) analysis of the results of microbiological studies of biomaterials from puerperas and their newborns was carried out in 63 cases of early neonatal mortality with established diagnoses of intrauterine infections. In the study of the separated cervical canal, placenta samples, and amniotic fluid, seeding of coagulase-negative staphylococci was most frequently observed, among which the species Staphylococcus epidermidis dominated, Staphylococcus hominis, Staphylococcus haemolyticus, Staphylococcus warneri also met. Frequent isolation of group B streptococci from the placenta and amniotic fluid was revealed in comparison with the material from the cervical canal.The information content of the microbiological study of materials from the puerpera and the newborn in terms of confirmation of the pathogen and the fact of its transmission from mother to fetus/newborn does not exceed 30%. Even with high contamination of the genital tract of the puerpera, placenta or amniotic fluid, examination of the materials from the newborn immediately after birth often does not allow to identify the causative agent, probably due to the low degree of contamination at the initial stage of development of the infectious process. An increase in the diagnostic value of microbiological research can be facilitated by an increase in the frequency of examinations, the number of samples taken; the use of techniques to increase the sensitivity of cultural research at the stage of analysis; the use of molecular genetic methods, especially in the study of materials from newborns.