https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 Isolates from colonic spirochetosis in humans show high genomic divergence and potential pathogenic features but are not detected using standard primers for the human microbiota https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46669 Brachyspira aalborgi type strain, 513A. Also, 16S analysis of the mucosa-associated microbiota was performed in the cases and nonspirochetosis controls. We found one isolate to be of the species Brachyspira pilosicoli; all remaining isolates were of the species Brachyspira aalborgi. Besides displaying extensive genetic heterogeneity, the isolates harbored several mucin-degrading enzymes and other virulence-associated genes that could confer a pathogenic potential in the human colon. We also showed that 16S amplicon sequencing using standard primers for human microbiota studies failed to detect Brachyspira due to primer incompatibility. IMPORTANCE This is the first report of whole-genome analysis of clinical isolates from individuals with colonic spirochetosis. This characterization provides new opportunities in understanding the physiology and potentials of these bacteria that densely colonize the gut in the individuals infected. The observation that standard 16S amplicon primers fail to detect colonic spirochetosis may have major implications for studies searching for associations between members of the microbiota and clinical conditions such as irritable bowel syndrome (IBS) and should be taken into consideration in project design and interpretation of gastrointestinal tract microbiota in population-based and clinical settings.]]> Tue 29 Nov 2022 08:39:26 AEDT ]]> Compositional and functional differences of the mucosal microbiota along the intestine of healthy individuals https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38873 Bacteroides species and describe the antimicrobial resistance biogeography along the intestine. We also detail which species, at which locations, are involved with the tryptophan/indole pathway, whose malfunctioning has been linked to pathologies including inflammatory bowel disease. Our study thus provides invaluable resources for investigating mechanisms connecting gut microbiota and host pathophysiology.]]> Tue 22 Feb 2022 16:36:25 AEDT ]]> Colonic spirochetosis is associated with colonic eosinophilia and irritable bowel syndrome in a general population in Sweden https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:27132 Brachyspira in colonic biopsies, is uncommon and considered of doubtful significance. We aimed to determine the prevalence of CS in the general population, identify subtle colon pathologies, and evaluate a link with symptoms of IBS. Colonoscopy was performed in 745 subjects (aged 19-70 years, mean age 51 years, 43% male) with biopsies (ileum and 4 colonic sites) from a random population sample, Stockholm, Sweden, who completed a validated questionnaire of gastrointestinal symptoms; IBS was identified by Rome III criteria. CS was identified by histology and immunohistochemistry. In a general population, 17 individuals (2.28%; 95% confidence interval, 1.2%-3.5%) were diagnosed as having CS by histology; 6 (35%) had IBS. CS was always present in the sigmoid colon, but only 14 rectal biopsies. Eosinophils were increased in colon biopsies in CS cases versus controls, in the transverse (P =.02), sigmoid colon (P =.001), and rectum (P =.0005) with subepithelial eosinophil clusters (P =.053). Lymphoid follicles (at any site) were present in 13 CS (P =.0003). There was a 3-fold increased risk of IBS in CS (odds ratio, 3.59; 95% confidence interval, 1.27-10.11; P =.015). Polyps and diverticular disease were similar in CS cases and controls. The prevalence of CS in a general population is 2% and associated with nonconstipating IBS. Colonic eosinophilia with lymphoid follicles may signify the presence of CS.]]> Sat 24 Mar 2018 07:33:02 AEDT ]]> Towards a healthy stomach? Helicobacter pylori prevalence has dramatically decreased over 23 years in adults in a Swedish community https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:23838 Helicobacter pylori (H. pylori) infection may be declining but there is a lack of recent longitudinal population studies. We evaluated the changing epidemiology over a 23-year period in Sweden. Materials and methods: In 1989, the validated Abdominal Symptom Questionnaire (ASQ) was mailed to a random sample of inhabitants (ages 22-80 years) in a Swedish community, and 1097 (87%) responded. H. pylori serology was analysed in a representative subsample (n = 145). Twenty-three years later, the ASQ was mailed again using similar selection criteria, and 388 out of 1036 responders had an upper endoscopy with assessment of H. pylori and corpus atrophy status. Results: The prevalence of positive H. pylori serology decreased from 37.9% (1989) to 15.8% (2012), corresponding to a decrease in odds of 75% per decade (odds ratio (OR): 0.25; 95% confidence interval (CI): 0.11-0.59, p = 0.001) independent of age, gender, body mass index (BMI) and level of education, with a pattern consistent with a birth cohort effect. The prevalence increased with increasing age (p = 0.001). The prevalence of H. pylori on histology in 2012 was 11.4% (95% CI 8.6-15.0). The prevalence of corpus atrophy on serology and/or histology in 2012 was 3.2% (95% CI 1.8-5.5); all cases were ≥57 years old. Conclusion: The stomach is healthier in 2012 compared with 1989. H. pylori prevalence in adults has decreased over the last two decades to a level where clinical management might be affected.]]> Sat 24 Mar 2018 07:12:10 AEDT ]]> Diverticulosis is not associated with altered gut microbiota nor is it predictive of future diverticulitis: a population-based colonoscopy study https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:53921 Mon 22 Jan 2024 16:42:54 AEDT ]]> The gut microbiota in collagenous colitis shares characteristics with inflammatory bowel disease-associate dysbiosis https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41838 Mon 15 Aug 2022 10:14:15 AEST ]]> Ileocolonic histopathological and microbial alterations in the irritable bowel syndrome: a nested community case-control study https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:39241 P = 0.022 adjusted for age, sex, and smoking). Cecal IELs were increased in IBS—diarrhea (relative risk ratio = 2.03, 95% confidence interval 1.13–3.63, P = 0.017). No difference was observed in alpha diversity of MaM or fecal microbiota based on IEL count. There was no difference in beta diversity of the MaM according to IEL count in the terminal ileal (TI) (P = 0.079). High TI IEL counts associated with a significant expansion of the genus Blautia (P = 0.024) and unclassified Clostridiales (P = 0.036) in colon MaM. Discussion: A modest but significant increase in IELs was observed in IBS vs. controls in a population-based setting. Subtle TI and cecal inflammation may play a pathogenic role in IBS but needs confirmation. Modest but discernible differences in the colonic MaM were seen according to TI IEL count but not IBS status.]]> Fri 27 May 2022 14:39:27 AEST ]]> No distinct microbiome signature of irritable bowel syndrome found in a Swedish random population https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46130 Fri 11 Nov 2022 15:21:48 AEDT ]]>