RESUMEN

Recent evidence indicates that the gut microbiota (GM) has a significant impact on the inflammatory bowel disease (IBD) progression. Our aim was to investigate the GM profiles, the Microbial Dysbiosis Index (MDI) and the intestinal microbiota-associated markers in relation to IBD clinical characteristics and disease state. We performed 16S rRNA metataxonomy on both stools and ileal biopsies, metabolic dysbiosis tests on urine and intestinal permeability and mucosal immunity activation tests on the stools of 35 IBD paediatric patients. On the GM profile, we assigned the MDI to each patient. In the statistical analyses, the MDI was correlated with clinical parameters and intestinal microbial-associated markers. In IBD patients with high MDI, Gemellaceae and Enterobacteriaceae were increased in stools, and Fusobacterium, Haemophilus and Veillonella were increased in ileal biopsies. Ruminococcaceae and WAL_1855D were enriched in active disease condition; the last one was also positively correlated to MDI. Furthermore, the MDI results correlated with PUCAI and Matts scores in ulcerative colitis patients (UC). Finally, in our patients, we detected metabolic dysbiosis, intestinal permeability and mucosal immunity activation. In conclusion, the MDI showed a strong association with both severity and activity of IBD and a positive correlation with clinical scores, especially in UC. Thus, this evidence could be a useful tool for the diagnosis and prognosis of IBD.

Asunto(s)

RESUMEN

Freshwater acidification (FA) has become a global environmental problem, posing a potential threat to freshwater ecosystems. The gut microbiota plays a crucial role in the host's response and adaptation to new environments. In this study, we investigated the changes in microbial communities in Red-eared slider (Trachemys scripta elegans) under acidic conditions to reveal the ecological impacts of acidification on freshwater turtles. The results showed that there were significant differences in ß-diversity (p = 0.03), while there were no significant differences in the α-diversity of gut microbiota in T. s. elegans between the different levels of acidification (pH of 5.5, 6.5, 7.5). Both the Gut Microbiome Health Index (GMHI) and the Microbial Dysbiosis Index (MDI) exhibited significant differences when comparing environments with a pH of 5.5 to those with a pH of 6.5 (p < 0.01). A comparative analysis between pH levels of 5.5 and 6.5 also revealed substantial differences (p < 0.01). Likewise, a comparative analysis between pH levels of 6.5 and 7.5 also revealed substantial differences (p < 0.01). At the phylum level, Firmicutes, Fusobacteria, and Bacteroidota formed a major part of the gut microbial community, Fusobacteria showed significant differences in different acidity environments (p = 0.03). At the genus level, Cetobacterium, Turicibacter, unclassified Eubacteriaceae, and Anaerorhabdus_furcosa_group showed significant differences in different acidity environments. The pH reduced interactivity in the gut microbiota of T. s. elegans. In addition, LEfSe analysis and functional prediction revealed that the potentially_pathogenic and stress_tolerant functional characteristics also showed significant differences in different acidity environments. The findings underscore the pivotal role of the gut microbiota in T. s. elegans in response to freshwater acidification and provide a foundation for further exploration into the impacts of acidification on freshwater ecosystems.

RESUMEN

OBJECTIVES: This study aimed to investigate the relationship between microbial communities and the severity of peri-implant mucosal bleeding in peri-implant mucositis. MATERIALS AND METHODS: Submucosal plaque samples were collected from 54 implants divided into the healthy implant (HI) group, peri-implant mucositis (PM) group, and peri-implantitis (PI) group. Sequencing of 16S rRNA was performed using the Illumina MiSeq platform. Alpha diversity (i.e., Shannon and Chao index) and beta diversity were used to measure microbial diversity within and between microbial communities, respectively. Differences in microbial taxa between groups were assessed via linear discriminate analysis effect size. Correlation between the modified sulcus bleeding index (mSBI) and microbial dysbiosis index (MDI) was examined using Spearman correlation analysis and linear models. RESULTS: The submucosal bacterial richness (Chao index) was positively correlated with the mean mSBI in the PM group. As the mean mSBI increased in the PM group, the beta diversity became closer to that of the PI group. In the PM group, the abundances of 47 genera were significantly correlated with the mean mSBI, and the MDI was positively associated with the mean mSBI. Fourteen of the forty-seven genera were discriminative taxa between the HI and PI groups, and the abundances of these biomarkers became closer to those in the PI group in the progression of peri-implant disease. CONCLUSIONS: A higher mSBI value corresponded to a higher risk of microbial dysbiosis in peri-implant mucositis. The biomarkers identified may be useful for monitoring the progression of peri-implant disease.

Asunto(s)

RESUMEN

Important evidence indicates the microbiota plays a key role in esophageal squamous cell carcinoma (ESCC). The esophageal microbiota was prospectively investigated in 18 patients with ESCC and 11 patients with physiological normal (PN) esophagus by 16S rRNA gene profiling, using next-generation sequencing. The microbiota composition in tumor tissues of ESCC patients were significantly different from that of patients with PN tissues. The ESCC microbiota was characterized by reduced microbial diversity, by decreased abundance of Bacteroidetes, Fusobacteria, and Spirochaetes. Employing these taxa into a microbial dysbiosis index demonstrated that dysbiosis microbiota had good capacity to discriminate between ESCC and PN esophagus. Functional analysis characterized that ESCC microbiota had altered nitrate reductase and nitrite reductase functions compared with PN group. These results suggest that specific microbes and the microbiota may drive or mitigate ESCC carcinogenesis, and this study will facilitate assigning causal roles in ESCC development to certain microbes and microbiota.

RESUMEN

Although the microbiome has a potential role in gastric cancer (GC), little is known about microbial dysbiosis and its functions. This study aimed to observe the associations between the alterations in gastric microbial communities and GC risk. The study participants included 268 GC patients and 288 controls. The 16S rRNA gene sequencing was performed to characterize the microbiome. Streptococcus_NCVM and Prevotella melaninogenica species were highly enriched in cases and controls, respectively. Those who were in the third tertile of P. melaninogenica showed a significantly decreased risk of GC in total (odds ratio (OR): 0.91, 95% confidence interval (CI): 0.38-0.96, p-trend = 0.071). Class Bacilli was phylogenetically enriched in cases, while phylum Actinobacteria, class Actinobacteria were related to the controls. The microbial dysbiosis index (MDI) was significantly higher for the cases compared with the healthy controls in the female population (p = 0.002). Females in the third tertile of the MDI showed a significantly increased risk of GC (OR: 2.66, 95% CI: 1.19-5.99, p-trend = 0.017). Secondary bile acid synthesis and biosynthesis of ansamycins pathways were highly abundant in cases and controls, respectively. Dysbiosis of gastric microbial communities is associated with an increased risk of GC specifically in females.

RESUMEN

BACKGROUND AND AIM: Small intestinal bacterial overgrowth (SIBO) has been proposed as an etiologic factor in irritable bowel syndrome, particularly the diarrhea-predominant subtype (IBS-D). We aimed to identify potential intestinal microbial pattern in IBS-D patients with SIBO. METHODS: Diarrhea-predominant irritable bowel syndrome patients fulfilling Rome III criteria were recruited and randomly divided into an exploratory cohort (57 cases) and a validation cohort (20 cases). SIBO was identified according to standard glucose hydrogen breath test. For 16S rRNA gene sequencing, samples of duodenal mucosa, duodenal fluid, rectal mucosa, and fresh feces were collected and performed. The α and ß diversity, as well as differences in microbial composition and function, in SIBO+ and SIBO- IBS-D subjects were evaluated. RESULTS: The microbial diversity and composition obviously differed between SIBO+ and SIBO- IBS-D in duodenal and rectal mucosa but not in duodenal fluid and fresh feces. For rectal mucosal microbiota, it displayed markedly reduced aerobe and Gram-negative bacteria and increased facultative anaerobe and Gram-positive bacteria, moreover, altered functions of microbial metabolism in SIBO+ IBS-D. Significantly higher rectal mucosa-related microbial dysbiosis index was observed in SIBO+ IBS-D, and a cut-off value at -0.37 had a sensitivity of 56.55% and specificity of 90.91% to identify the SIBO in IBS-D subjects. CONCLUSIONS: Mucosal microbiota, rather than luminal bacteria, has a more apparent dysbiosis in SIBO+ IBS-D patients relative to those without SIBO. Rectal mucosa-associated microbiota may act as a potential predictor of SIBO in IBS-D patients.

Asunto(s)

RESUMEN

Evidence shows that gut microbiota may play important roles in schizophrenia pathogenesis via the "gut-brain" axis, but the mechanisms remain unclear. Here, eighty-four patients with schizophrenia and 84 sex- and age-matched healthy controls were enrolled. Shotgun metagenomic sequencing and 16S rRNA sequencing were performed, and the gut microbiota-associated epitopes (MEs) were predicted, which, together with IgA content, were used to determine the gut microbiota composition associated with gut immune status. Patients with schizophrenia had significantly reduced gut microbiota richnesses compared with those of the healthy controls, and the gut microbiota compositions clearly distinguished the patients with schizophrenia from the healthy controls. Based on two-stage metagenomic-wide association studies, nineteen gut microbiota taxonomies were associated with schizophrenia, and the microbial dysbiosis (MD) index was calculated based on the abundance of differential taxonomies. We found that MD index was positively correlated with MEs diversity and gut IgA levels, and negatively correlated with gut microbiota richness. Glutamate synthase (GOGAT) was more active in the guts of patients with schizophrenia than in those of healthy controls, and high GOGAT activity was associated with altered gut microbiota taxonomies associated with gut IgA levels. Our results may imply a role of the microbiome in the etiology of schizophrenia and contribute to the development of microbiome targeted interventions for schizophrenia.

Asunto(s)