Alina R. Melkumyan

This article examines key aspects of the structural organization and functioning of a biobank, including the main stages of biological sample processing. Particular attention is paid to the implementation of research projects using preserved biological material and microbial strain collections. The article describes collection of microorganism strains and biological material in a cryobank, a division of the reference center for the verification of microbiological research results in coloproctology, established at the A. N. Ryzhikh National Medical Research Center of Coloproctology. This article presents the experience of a reference center collaborating with medical facilities in Russian regions within the biological risk monitoring system. A cryobanking system for samples in priority areas of biomedical research is described. The obtained results demonstrate the importance of an integrated approach to biobanking for improving the effectiveness of scientific and clinical developments.

Gut-brain axis conception is an important achievement in understanding relationship between the gastrointestinal and central nervous systems functioning. Objective. To study the nature of relationship between the gut and the brain. Materials and methods. An analysis of domestic and foreign reviews, original articles, monographs, clinical and laboratory studies descriptions published over the past 5 years and presented in PubMed, eLibrary and RSCI databases was carried out. The following keywords were used: «gut-brain» axis», «gut microbiota», «inflammation», «neuromodulation», «gastrointestinal tract». The number of sources equal 57 has been analyzed. Results. An analysis of neuroanatomical pathways, hormonal signals and the role of gut microbiota in the modulating brain functions is presented. The pathology resulting from disruption of relationships between the gut and the brain is considered. Current and future therapeutic strategies are being discussed. Conclusion. Studying the «gut-brain» axis has the potential to change approach to diagnosis, treatment and prevention of both gastrointestinal tract pathology and neurodegenerative diseases.

AIM: to assess the effect of laser therapy on wounds healing after open hemorrhoidectomy. PATIENTS AND METHODS: a single-centre, prospective, randomised study included 86 patients who underwent open hemorrhoidectomy using an ultrasound scalpel. In addition to the standard use of water-based ointments daily from days 1 to 7 after surgery and then once a week until the wounds were fully healed, laser treatment was performed on the wounds in patients in the main group (n = 46). Patients in the control group (n = 40) received only standard therapy (water-based ointments). Laser treatment was performed using a fibre laser with a wavelength of 970 nm in a non-contact manner with a defocused beam. The beam power was 20 W, the power density was 0.038 W/cm² and the mode was pulsed-periodic (impulse duration 50 ms, pause 100 ms). Each session lasted 4 minutes. Pain intensity was assessed with visual analogue scale (VAS). The rate of wound epithelialisation on the 30th day after and QoL using the SF-36 questionnaire. The microbiome of surgical wounds at various stages of treatment, a microbiological study was studied as well. RESULTS: on the 30th day after surgery, planimetric and cytological characteristics of wounds corresponded to complete epithelization in 42/46 (91%) patients of the main group and in 7/40 (18%) controls, p < 0,001. The pain intensity in the main group already from the 2nd day after surgery was 4 (4; 6) points and was significantly lower than in the control group — 6 (5; 7) points, p < 0,001. When comparing the patients’ quality of life indicators by SF-36 questionnaire on the 30th day after surgery, significant differences were revealed: physical functioning (PF) — 85 (75; 95) points in the main group, 80 (70; 85) — in the control group (p = 0.030); pain intensity (BP): 51 (41; 64) in the main group, vs 41 (22; 51) in the control, (p = 0.008); and role functioning conditioned by emotional state (RE) — 100 (66; 100) points vs 66 (17; 67), (p = 0.002). Microbiology showed that laser therapy already on the 7th day contributes to a significant reduction of postoperative wound infestation in the patients of the main group compared to the control group, and on the 21st day the difference becomes statistically significant — positive growth was noted in 23/42 (54.8%) patients of the main group and in 38/40 (95.0%) of the control group, p < 0.0001. CONCLUSION: the use of laser therapy for wounds after open hemorrhoidectomy allows to achieve good clinical results in healing time, decreased intensity of pain syndrome, decreased bacterial contamination of wounds, which, in turn, contributes to the improvement of the quality of life of operated patients and shortening of rehabilitation.

Objective. To study susceptibility of clinical Bacteroides spp. and Clostridium perfringens isolates to antimicrobial agents across different regions of the Russian Federation and to identify regional patterns of antimicrobial resistance. Materials and Methods. The study included 1,685 isolates of obligate anaerobic bacteria belonging to 107 species, isolated from patients in 60 regions of the Russian Federation during period from January 2023 to December 2024. Among them, 144 C. perfringens isolates from 37 regions, and 370 Bacteroides spp. isolates from 53 regions. Identification was performed using the MALDI-TOF MS method, antimicrobial susceptibility testing was conducted using the disk diffusion method and agar dilution method in accordance with the Russian guidelines «Determination of Microorganism Susceptibility to Antimicrobial Agents,» version 2024-02. Results. Significant variability in resistance levels was observed across different regions. Among Bacteroides spp. high resistance rates was detected for meropenem (48.92%), metronidazole (34.59%), and piperacillin-tazobactam (38.38%). C. perfringens demonstrated high susceptibility to vancomycin (93.75%) but considerable resistance to clindamycin (47.92%). Isolates of Bacteroides spp. exhibiting complete resistance to all tested antibiotics were found in 14 regions, while multidrug-resistant C. perfringens strains were identified in 7 regions. Conclusions. This study confirms a significant prevalence of antibiotic resistance among anaerobic microorganisms in Russian hospitals. Marked regional differences in resistance patterns emphasize the need for enhanced monitoring and the development of region-specific antimicrobial therapy strategies.

AIM: to reveal biofilms in chronic anal fissure (CAF) bacterial composition.PATIENTS AND METHODS: patient A., 40 years old, with chronic posterior and anterior anal fissures with sphincter spasm underwent a lateral subcutaneous sphincterotomy with excision of the CAFs. Before the operation swabs were taken from fissures for microbiology. Removed specimens were placed in fixing solutions. Microbiological studies including 16S rRNA gene sequencing and MALDI-ToF mass spectrometry of isolated cultures were carried out to assess the bacterial composition of CAFs. Microscopic studies which included scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to search for the biofilm location of microorganisms. Conclusions about the presence of biofilms were made during the comparison of photographs with reliable images described in the literature.RESULTS: a wide variety of bacteria (56 genera) was detected in the tissues forming the CAF based on sequencing of 16S rRNA genes; swab's mass spectrometry revealed only E. coli and P. anaerobius in significant concentrations. Using SEM on one of the sections of the excised CAF were found biofilms containing bacterial cells immersed in an extracellular matrix (which size was within the limits of 2 microns); similar structures weren't detected outside the CAF. On TEM an accumulation of bacterial cells, surrounded by an extracellular polymer matrix, what was interpreted as a biofilm of gram-negative bacteria, was identified. After 7 months, the patient retained a non-healing postoperative wound in the area of the previously excised posterior fissure. After repeated sowing, E. coli and S. gallolyticus were obtained in significant concentrations. Excision of the scarred edges of the wound and the prescribed conservative treatment allowed the wound to epithelize within 3 weeks.CONCLUSION: the results show that microbial biofilms can be localized in the CAF. Further researches are needed for reliable conclusions about biofilm organization in CAF and their effect on pathological and reparative processes.

This review presents modern methods for assessing the antagonistic activity of microorganisms used to study probiotic candidate strains and their interactions with opportunistic microorganisms. Along with the classical two-layer agar method, alternative approaches are considered, such as the method of point analysis (with modifications), the method of delayed antagonism, the method of perpendicular «strokes», the disk diffusion method (with modifications), the method of microtiter plates and the method of co-cultivation. Special attention is paid to the advantages and limitations of each method, as well as their applicability for a detailed study of the mechanisms of action of probiotics and their potential in fighting infections. It is emphasized that the introduction of modern methods makes it possible to evaluate antagonistic activity more accurately, quickly and reproducibly, as well as automate the research process, which is especially important when working with a large number of strains and for the development of new probiotic drugs. The objectives and tasks of the review are to generalize and systematize modern methods used to determine the antagonistic activity of microorganisms, identify their advantages and disadvantages, and determine promising areas of research in this area. Conclusion. Methods for studying the antagonistic activity of microorganisms represent a variety of approaches that can be used both separately and in combination with each other. This allows for a deeper understanding of the mechanisms of interaction between microorganisms and the development of new strategies to combat infections. Research in this area has significant potential for developing new therapeutic agents and improving the health of the general population.

Aim: to improve treatment outcomes for patients after open hemorrhoidectomy. Materials and methods. The results of treatment of 62 patients after open hemorrhoidectomy by ultrasonic scalpel, who were randomized into the main and control groups, 31 persons in each group, were analyzed. The patients of the main group underwent dressing of postoperative wounds using water-soluble ointments in combination with laser irradiation daily from day 2 after the surgical intervention and further on days 14, 21 and 30. In the control group only dressing with the use of water-soluble ointments was performed. In the postoperative period the terms of wound healing were determined based on the data of visual inspection, anoscopy, planimetric and cytologic methods of examination. Microbiological (culture) examination, assessment of pain syndrome intensity using visual analog scale on days 1–7, 14, 21, and 30 after surgical treatment and quality of life using SF-36 questionnaire before hemorrhoidectomy and on day 30 after it were also performed. Results. On day 30 wound healing occurred in 29/31 (94 %) patients of the main group and only in 5/31 (16 %) patients of the control group (p < 0.001). The growth of microorganisms in the main group was noted on day 2 in 31/31 (100 %) cases, on day 21 — in 20/28 (71 %) cases (p = 0.001); in the control group: on day 2 — in 27/31 (87 %), on day 21 — in 30/31 (97 %) cases, although the significance of differences was not achieved (p = 0.4). The level of pain syndrome was already lower from the second day after surgical treatment in patients of the main group and amounted to 5 (4; 6) points, in the control group — 6 (5; 7) (p = 0.016), and on day 30 — 0 (0; 0) points in the main group and 1 (0; 2) point in the control group (p < 0.001). Before treatment, the groups were comparable in quality of life; on day 30, statistically significant differences were noted in three indicators: physical functioning (PF) — 80 (75; 93) points in the main group vs. 80 (70; 80) points in the control group (p = 0.041); the criterion of role functioning due to emotional state (RE) — 100 (66; 100) points vs. 66 (17; 67) points (p = 0.002), and the criterion reflecting the intensity of pain and its impact on daily activities (BP) — 51 (37; 62) points vs. 41 (22; 51) points (p = 0.023). Conclusion. Application of laser therapy after hemorrhoidectomy with ultrasonic scalpel promotes stimulation of reparation processes, shortening of postoperative wound healing time, reduction of bacterial contamination of wounds, reduction of pain syndrome intensity and improvement of quality-of-life indicators in patients of the main group in comparison with the control group.

Invasive listeriosis (IL) is a disease caused by Listeria monocytogenes due to consumption of contaminated food. Immunosuppression, which is one of the rea

Background. Invasive listeriosis (IL) is a disease caused by Listeria monocytogenes due to consumption of contaminated food. Immunosuppression, which is one of the reasons for susceptibility to infection in risk groups, can be increased due to a viral illness. In the early years of the COVID-19 pandemic, changes occurred both in the performance of the sample of patients with IL in the meningitis-septicemia (MS) cohort and in the genomic characteristics of L. monocytogenes that caused the disease. The purpose of the study. To continue monitoring IL in the Moscow region, compare samples of patients with IL and clinical isolates of L. monocytogenes isolated in 2022 with a high incidence of COVID-19 and in 2023—04.2024 with a decrease in the incidence of this infection. Matherial and methods. Clinical isolates isolated from Moscow hospital patients diagnosed with IL with manifestations of MS were studied using multilocus and whole-genome sequencing methods, followed by bioinformatic analysis. The parameters of the patient groups were compared based on epicrisis data. Results. Comparison of subgroups of patients with IL showed that the “2022” subgroup had a higher proportion of male patients, patients diagnosed with COVID-19, pneumonia/pulmonary fibrosis, and a higher incidence of deaths. In the subgroup “2023—04.2024” there was a higher proportion of patients with cancer and a higher variety of previous or concomitant viral infections. Clinical isolates of L. monocytogenes were represented by 19 genotypes, 5 of which belonged to phylogenetic lineage I (PLI). In the period 2023—04.2024, the genetic characteristics of the pathogen of IL in the Moscow region continued to change. The diversity of PLII isolates has increased, the proportion of PLI isolates has decreased, which, as before the pandemic, are represented by L. monocytogenes of two serogroups: 4b and 1/2b. Conclusion. The noted changes in the spectrum of IL pathogen genotypes are not only a consequence of the impact of the COVID-19 pandemic on the health of the population, but also trends in the food industry.

Anaerobic bacteria can cause various infectious complications, leading to severe outcomes and mortality in patients. Problems associated with the microbiological diagnosis of obligate anaerobic bacteria and determination of sensitivity to antibiotics direct doctors to prescribe broad-spectrum drugs in the treatment of anaerobic infections, which leads to an increase in resistance among anaerobes throughout the world. This article discusses modern methods for determining the sensitivity of anaerobes to antibacterial drugs. The authors note that the development of “fast” laboratory testing methods with the introduction of new technologies and the development of test systems for the detection of anaerobic bacteria and resistance genes is a priority and promising direction.