The liver fluke, Opisthorchis felineus, is widely distributed throughout Europe and large parts of the Russian Federation. In Western Siberia, information about opisthorchiasis is lacking although infection may lead to severe liver and bile duct diseases. We aimed to assess the current prevalence of O. felineus infection along with associated risk factors and morbidity in rural Western Siberia. We conducted a community-based, cross-sectional study in the rural Shegarskiy district, Tomsk Oblast, Russian Federation. All household members (≥ 7 years) present on the survey day were enrolled (n = 600). Two stool samples per person were examined for helminth eggs, using PARASEP (DiaSys Ltd, UK). The number of eggs per gram (EPG) of feces was recorded. Each study participant was interviewed to determine risk factors, using a pre-tested questionnaire. An abdominal ultrasonography examination of liver and bile ducts was performed with a mobile, high resolution ultrasound device. In total, 488 persons completed assessments (two stool samples, completed questionnaires); of those, 436 individuals had an US examination. We observed a prevalence of O. felineus infection of 60.2%. Significant risk factors for infection were the consumption of river fish (odds ratio [OR] 2.4, 95% CI 1.52–3.95, p<0.001), particularly stock fish (OR from multivariable analysis [mOR] 3.2, 95% CI 2.63–3.80, p<0.001), smoked fish (mOR 1.5, 95% CI 1.24–1.72, p<0.001), frozen fish (mOR 1.6, 95% CI 1.29–2.02, p<0.001), and raw fish (mOR 1.4, 95% CI 1.05–1.84, p = 0.022); and fishing activities (mOR 1.2, 95% CI 1.03–1.43, p = 0.019). Women had a higher risk of infection than men. Infection was associated positively with age and negatively with socio-economic status. The respondents’ general awareness of opisthorchiasis was quite high (93.2%), but their knowledge about infection transmission and prevention was insufficient. Children aged 7–18 years old had a lower level of awareness compared to adults. The abdominal ultrasonography results demonstrated a strong association between O. felineus infection and gallbladder stones (mOR 2.8, 95% CI 1.33–6.04, p = 0.007) and periductal fibrosis of intrahepatic bile ducts (mOR 1.9, 95% CI 1.08–3.46, p = 0.026). O. felineus infection is highly prevalent in rural regions of Western Siberia, and associated with severe hepatobiliary pathology. Identified risk factors will be used to develop a comprehensive targeted O. felineus infection control program. Opisthorchis felineus is a trematode (liver fluke) that infects the hepatobiliary systems of humans in endemic regions. The infection may lead to severe liver and bile duct diseases, making it a public health issue in endemic communities like Western Siberia. Yet, little information is available from this region about its epidemiology. We aimed to assess the current prevalence of O. felineus infection along with associated risk factors and morbidity in one district in rural Western Siberia. We conducted a cross-sectional community-based study in the Shegarskiy district, Tomsk Oblast, Russian Federation. All household members (≥ 7 years) present on the survey day were enrolled (n = 600). Two stool samples per person were examined for helminth eggs. We interviewed study participants to determine risk factors using a questionnaire. An abdominal ultrasonography examination was performed to assess liver and bile duct pathology. In total, 488 persons completed assessments. We found a high O. felineus infection prevalence of 60.2%. Women and older study participants had a higher risk of infection. The consumption of river fish, particularly stock, smoked, frozen and raw fish; and fishing activities increased the risk of infection. Study participants with a higher socio-economic status had a lower risk of infection. The ultrasonography showed that participants with infection had an increased risk of gallbladder stones and bile duct pathologies. Our study provides valuable information about Opisthorchis infection prevalence, its risk factors and morbidity in rural Siberia. The results will be useful for developing a multidisciplinary, community-based control program against Opisthorchis infection in endemic regions.

Background. A functional interplay between BAs and microbial composition in gut is a well‐documented phenomenon. In bile, this phenomenon is far less studied, and with this report, we describe the interactions between the BAs and microbiota in this complex biological matrix. Methodology. Thirty‐seven gallstone disease patients of which twenty‐one with Opisthorchis felineus infection were enrolled in the study. The bile samples were obtained during laparoscopic cholecystectomy for gallstone disease operative treatment. Common bile acid composition was measured by LC‐MS/MS. Gallbladder microbiota were previously analyzed with 16S rRNA gene sequencing on Illumina MiSeq platform. The associations between bile acid composition and microbiota were analyzed. Results. Bile acid signature and Opisthorchis felineus infection status exert influence on beta‐diversity of bile microbial community. Direct correlations were found between taurocholic acid, taurochenodeoxycholic acid concentrations, and alpha‐diversity of bile microbiota. Taurocholic acid and taurochenodeoxycholic acid both show positive associations with the presence of Chitinophagaceae family, Microbacterium and Lutibacterium genera, and Prevotella intermedia. Also, direct associations were identified for taurocholic acid concentration and the presence of Actinomycetales and Bacteroidales orders, Lautropia genus, Jeotgalicoccus psychrophilus, and Haemophilus parainfluenzae as well as for taurochenodeoxycholic acid and Acetobacteraceae family and Sphingomonas genus. There were no differences in bile acid concentrations between O. felineus-infected and noninfected patients. Conclusions/Significance. Associations between diversity, taxonomic profile of bile microbiota, and bile acid levels were evidenced in patients with cholelithiasis. Increase of taurochenodeoxycholic acid and taurocholic acid concentration correlates with bile microbiota alpha‐diversity and appearance of opportunistic pathogens.

Backgraund: The result of comparative study of oropharyngeal microbiota taxonomic composition in patients with different severity level of bronchial asthma (BA) and chronic obstructive pulmonary disease (COPD) is presented in this paper. Aims: To compare oropharyngeal microbiota composition in case of bronchial asthma and chronic obstructive pulmonary disease in different severity levels. Metods: 138 patients, 50 with BA and 88 with COPD were studied. For each patient was collected anamnesis vitae, swab from the back of the throat and performed physical examination. High-throughput 16S ribosomal RNA gene sequencing and bioinformatic analysis was employed to characterize the microbial communities. Results: As a result of the study was found a number of differences on various taxonomic levels in microbiota’s composition within group of patients with different severity level of BA and group of patients with different severity level of COPD and between those groups. COPD patients with GOLD 1–2 in comparison with GOLD 3–4 patiens are marked by prevalence of species Brevibacterium aureum, genus Scardovia, Coprococcus, Haemophilus, Moryella, Dialister, Paludibacter and decrease of Prevotella melaninogenica species. BA patients with severe uncontrolled asthma in comparison with patients which have mild persistent asthma are marked by decrease of Prevotella and increase of species Bifidobacterium longum, Prevotella nanceiensis, Neisseria cinerea, Aggregatibacter segnis and genus Odoribacter, Alloiococcus, Lactobacillus, Megasphaera, Parvimonas, Sneathia. Patient’s microbiota in BA group in comparison with COPD group is characterized by the prevalence of Prevotella melaninogenica and genus Selenomonas, Granulicatella и Gemella, and decrease of Prevotella nigrescens, Haemophilus influenza and genus Aggregatibacter, Alloiococcus, Catonella, Mycoplasma, Peptoniphilus и Sediminibacterium. There are no differences between microbiota composition in case of severe uncontrolled BA and very severe COPD. Conclusion: Lack of differences in oropharyngeal microbiota taxonomic composition between patients with severe uncontrolled BA and very severe COPD allow us to suggest a similarity of bronchopulmonary system condition in case of diseases' severe stages.

Alterations in the gut microbiome and a "leaky" gut are associated with Parkinson's disease (PD), which implies the prospect of rebalancing via dietary intervention. Here, we investigate the impact of a diet rich in resistant starch on the gut microbiome through a multi-omics approach. We conducted a randomized, controlled trial with short-term and long-term phases involving 74 PD patients of three groups: conventional diet, supplementation with resistant starch, and high-fibre diet. Our findings reveal associations between dietary patterns and changes in the gut microbiome's taxonomic composition, functional potential, metabolic activity, and host inflammatory proteome response. Resistant starch supplementation led to an increase in Faecalibacterium species and short-chain fatty acids alongside a reduction in opportunistic pathogens. Long-term supplementation also increased blood APOA4 and HSPA5 and reduced symptoms of PD. Our study highlights the potential of dietary interventions to modulate the gut microbiome and improve the quality of life for PD patients.