The development of dental implantology is based on the detailed study of the interaction of implants with the surrounding tissues and methods of osteogenesis stimulation around implants, which has been confirmed by the increasing number of scientific publications presenting the results of studies related to both the influence of the chemical composition of dental implant material as well as the method of its surface modification on the key operational characteristics of implants. The main materials for dental implant manufacturing are Ti and its alloys, stainless steels, Zr alloys (including ceramics based on ZrO₂), and Ta and its alloys, as well as other materials (ceramics based on Al₂O₃, Si₃N₄, etc.). The review presents alloy systems recommended for use in clinical practice and describes their physical–mechanical and biochemical properties. However, when getting into the body, the implants are subjected to various kinds of mechanical influences, which are aggravated by the action of an aggressive biological environment (electrolyte with a lot of Cl⁻ and H⁺); it can lead to the loss of osteointegration and to the appearance of the symptoms of the general intoxication of the organism because of the metal ions released from the implant surface into the biological tissues of the organism. Since the osteointegration and biocompatibility of implants depend primarily on the properties of their surface layer (it is the implant surface that makes contact with the tissues of the body), the surface modification of dental implants plays an important role, and all methods of surface modification can be divided into mechanical, physical, chemical, and biochemical methods (according to the main effect on the surface). This review discusses several techniques for modifying dental implant surfaces and provides evidence for their usefulness.

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has significantly impacted global healthcare, underscoring the importance of exploring the virus’s effects on infected individuals beyond treatments and vaccines. Notably, recent findings suggest that SARS-CoV-2 can infect the gut, thereby altering the gut microbiota. This study aimed to analyze the gut microbiota composition differences between COVID-19 patients experiencing mild and severe symptoms. We conducted 16S rRNA metagenomic sequencing on fecal samples from 49 mild and 43 severe COVID-19 cases upon hospital admission. Our analysis identified a differential abundance of specific bacterial species associated with the severity of the disease. Severely affected patients showed an association with Enterococcus faecium, Akkermansia muciniphila, and others, while milder cases were linked to Faecalibacterium prausnitzii, Alistipes putredinis, Blautia faecis, and additional species. Furthermore, a network analysis using SPIEC-EASI indicated keystone taxa and highlighted structural differences in bacterial connectivity, with a notable disruption in the severe group. Our study highlights the diverse impacts of SARS-CoV-2 on the gut microbiome among both mild and severe COVID-19 patients, showcasing a spectrum of microbial responses to the virus. Importantly, these findings align, to some extent, with observations from other studies on COVID-19 gut microbiomes, despite variations in methodologies. The findings from this study, based on retrospective data, establish a foundation for future prospective research to confirm the role of the gut microbiome as a predictive biomarker for the severity of COVID-19.

Aim. To identify features of the taxonomic composition of the oropharyngeal microbiota of COVID-19 patients with different disease severity. Materials and methods. The study group included 156 patients hospitalized with confirmed diagnosis of COVID-19 in the clinical medical center of Yevdokimov Moscow State University of Medicine and Dentistry between April and June 2021. There were 77 patients with mild pneumonia according to CT (CT1) and 79 patients with moderate to severe pneumonia (CT2 and CT3). Oropharyngeal swabs were taken when the patient was admitted to the hospital. Total DNA was isolated from the samples, then V3V4 regions of the 16s rRNA gene were amplified, followed by sequencing using Illumina HiSeq 2500 platform. DADA2 algorithm was used to obtain amplicon sequence variants (ASV). Results. When comparing the microbial composition of the oropharynx of the patients with different forms of pneumonia, we have identified ASVs associated with the development of both mild and severe pneumonia outside hospital treatment. Based on the results obtained, ASVs associated with a lower degree of lung damage belong predominantly to the class of Gram-negative Firmicutes (Negativicutes), to various classes of Proteobacteria, as well as to the order Fusobacteria. In turn, ASVs associated with a greater degree of lung damage belong predominantly to Gram-positive classes of Firmicutes Bacilli and Clostridia. While being hospitalized, patients with severe pneumonia demonstrated negative disease dynamics during treatment significantly more often. Conclusion. We have observed differences in the taxonomic composition of the oropharyngeal microbiota in patients with different forms of pneumonia developed outside hospital treatment against COVID-19. Such differences might be due to the presumed barrier function of the oropharyngeal microbiota, which reduces the risk of virus titer increase.

Objective. To study the effectiveness of carvedilol, tiotropium bromide and indacaterol in complex therapy on clinical and functional parameters in patients with CHF of ischemic origin in combination with COPD. Material and methods. The study included 98 patients aged 45–75 years, suffering from CHF II–III FC with post-infarction cardiosclerosis, LV ejection fraction less than 45% and COPD of 2–3 degrees (GOLD). In addition to basic therapy all patients received carvedilol and were divided into 3 groups: tiotropium was administered in the 1st (36 people), indacaterol in the 2nd (32 people), and a combination of tiotropium and indacaterol in the 3rd (30 people). At baseline and after 6 months of follow-up, the clinical condition, exercise tolerance were assessed, the quality of life was assessed using the clinical state rating scale (SHOX) and MRC dyspnea scale, questionnaires of University of Minnesota (MLHFQ) and St. George’s Hospital (SGRQ). EchoCG, 24-hour blood pressure monitoring with simultaneous ECG recording, and spirometry test were performed. Results. The use of carvedilol in combination with tiotropium and indacaterol (both in mono and in combination) as part of complex therapy of CHF II–III FC of ischemic genesis with COPD is safe and effective: the clinical condition of patients improved, quality of life, frequency and duration of ischemia episodes decreased significantly, significantly increased LVEF, decreased pulmonary hypertension, improved condition of the bronchopulmonary system.

Relevance. The COVID-19 pandemic caused by the SARS-CoV-2 virus has demonstrated the critical importance of understanding the mechanisms of transmission and finding effective methods of prevention. Particular attention has been paid to the role of oral hygiene, as the oral cavity serves as a major route of transmission. Studies show that the composition of the oral microbiota can influence the course and outcome of COVID-19 disease. Therefore, there is a need to study the effects of oral antiseptics on the microbiome, which may offer new opportunities for the prevention and treatment of this disease.Objective. The aim of this study is to evaluate the effectiveness of the oral cleansing foam «Parodontol PROF» in reducing the pathogenic microflora of the oral cavity in patients with COVID-19 and to assess its effect on the risk of secondary infections.Materials and methods. The study was conducted on the basis of the Clinical Medical Centre «Kuskovo» of Russian University of Medicine. It included 450 patients with a confirmed diagnosis of COVID-19. The participants were divided into two groups: the test group used oral cleansing foam, while the control group used no additional oral hygiene. Comparative analyses of the taxonomic composition of the oropharyngeal microbiota and dental plaque before and after the use of the cleansing foam were performed.Results. The study showed that patients who regularly used the cleansing foam «Parodontol PROF» had a significant decrease in the representation of pathogens, including Mycoplasma, and an increase in the number of beneficial commensals such as Lactococcus and Lactobacillus. These changes indicate the potential efficacy of this product to improve oral hygiene and reduce the risk of secondary infections.Conclusion. The study supports the hypothesis that improving oral hygiene with specialised antiseptic agents, such as a cleansing foam, may help to reduce pathogenic microflora in the oral cavity in patients with COVID-19. This, in turn, may reduce the risk of pathogen migration into the lower respiratory tract and the development of secondary infections. The findings emphasise the importance of further research in this area and the development of comprehensive approaches to oral hygiene management in the context of infectious diseases.

The majority of metagenomic studies are based on the study of bacterial biota. At the same time, the COVID-19 pandemic has prompted interest in the study of both individual fungal pathogens and fungal communities (i.e., the mycobiome) as a whole. Here, in this work, we investigated the human gut mycobiome during COVID-19. Stool samples were collected from patients at two time points: at the time of admission to the hospital (the first time point) and at the time of discharge from the hospital (the second time point). The results of this study revealed that Geotrichum sp. is more represented in a group of patients with COVID-19. Therefore, Geotrichum sp. is elevated in patients at the time of admission to the hospital and underestimated at the time of discharge. Additionally, the influence of factors associated with the diversity of fungal gut microbiota was separately studied, including disease severity and age factors.