Gut Pathogens最新文献

Introduction: Depression and anxiety are pervasive mental health disorders with substantial global burdens. Probiotics, live microorganisms known for their health benefits, have emerged as a potential therapeutic intervention for these conditions. This systematic review and meta-analysis aim to evaluate the strain-specific effects of probiotics on relieving depressive and anxiety symptoms while elucidating underlying mechanisms.

Methods: EMBASE, Cochrane CENTRAL and PubMed/Medline were systematically queried to identify studies released until May 15, 2024. Randomized Controlled Trials (RCTs) that employed standardized assessment tools for depression and anxiety namely Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HAMD), Depression Anxiety Stress Scales (DASS), or Montgomery-Asberg Depression Rating Scale (MADRS) were included.

Results: 12 RCTs involving 707 participants were included. Seven RCTs utilizing the BDI questionnaire demonstrated a significant decrease in depressive symptoms favoring probiotics containing strains such as Lactobacillus acidophilus, Lactobacillus paracasei, Lactobacillus casei, Lactobacillus plantarum, Lactobacillus salivarius, Bifidobacterium bifidum, Bifidobacterium lactis, Bifidobacterium breve, and Bifidobacterium longum (MD: -2.69, CI95%: -4.22/-1.16, p value: 0.00). Conversely, RCTs using HAMD showed a non-significant reduction in depressive symptoms (MD: -1.40, CI95%: -3.29/0.48, p value: 0.14). RCTs employing DASS and MADRS scales also showed no significant differences.

Conclusion: This meta-analysis offers valuable insights into the strain-specific effects of probiotics containing Lactobacillus and Bifidobacterium species on depressive and anxiety symptoms. While our findings suggest a significant reduction in depressive symptoms based on the BDI scale favoring probiotics, the lack of significant effects observed on the HAMD, DASS, and MADRS scales underscores the complexity inherent in these conditions. It is imperative to acknowledge the mixed results across different measurement scales, indicating the need for cautious interpretation. Therefore, we advocate for a nuanced understanding of probiotics' impacts on various dimensions of mood, emphasizing the necessity for further research.

Background: The use of gastrointestinal disease multiplex polymerase chain reaction (GI PCR) testing has become common for suspected gastrointestinal infection. Patients often test positive for multiple pathogens simultaneously through GI PCR, although the clinical significance of this is uncertain.

Methods: This retrospective cohort study investigated risk factors and clinical outcomes associated with detection of multiple (as opposed to single) pathogens on GI PCR. We included adult patients who underwent GI PCR testing from 2020 to 2023 and had one or more pathogens detected. We compared patients with multiple versus those with single pathogens and hypothesized that immunosuppression would be a risk factor for detection of multiple pathogens. We further hypothesized that, during the 90 days after GI PCR testing, patients with multiple pathogens would have worse clinical outcomes such as increased rates of emergency department (ED) visits, death, hospitalization, or ambulatory care visits.

Results: GI PCR was positive in 1341 (29%) of tested patients; 356 patients had multiple pathogens and 985 had one pathogen. The most common pathogens included Enteropathogenic Escherichia coli (EPEC, 27%), norovirus (17%), and Enteroaggregative E. coli (EAEC, 14%) in both multi- and singly positive patients. Immunosuppression was not associated with multiple pathogens (adjusted odds ratio [aOR] 1.35, 95% CI 0.96, 1.86). The factors most associated with multiple pathogens were Hispanic ethnicity (OR 1.86, 95% CI 1.42, 2.45) and chronic kidney disease (OR 1.69, 95% CI 1.13, 2.49). Patients with multiple pathogens were more likely to have ED visits during the 90 days after GI PCR testing (40% vs. 32%, p < 0.01), but they were not more likely to die, be hospitalized, or to have ambulatory medical visits.

Conclusions: Immunosuppression was not associated with detection of multiple as opposed to single pathogens on GI PCR testing. There were worse clinical outcomes associated with detection of multiple pathogens, although these effects were modest.

Background: While significant research exists on gut microbiota changes after anti-tumor necrosis factor-alpha (anti TNF-α) therapy for ulcerative colitis, little is known about the longitudinal changes related to the effects of anti TNF-α. This study aimed to investigate the dynamics of gut microbiome changes during anti TNF-α (adalimumab) therapy in patients with ulcerative colitis (UC).

Results: The microbiota composition was affected by the disease severity and extent in patients with UC. Regardless of clinical remission status at each time point, patients with UC exhibited microbial community distinctions from healthy controls. Distinct amplicon sequence variants (ASVs) differences were identified throughout the course of Adalimumab (ADA) treatment at each time point. A notable reduction in gut microbiome dissimilarity was observed only in remitters. Remitters demonstrated a decrease in the relative abundances of Burkholderia-Caballeronia-Paraburkholderia and Staphylococcus as the treatment progressed. Additionally, there was an observed increase in the relative abundances of Bifidobacterium and Dorea. Given the distribution of the 48 ASVs with high or low relative abundances in the pre-treatment samples according to clinical remission at week 8, a clinical remission at week 8 with a sensitivity and specificity of 72.4% and 84.3%, respectively, was predicted on the receiver operating characteristic curve (area under the curve, 0.851).

Conclusions: The gut microbiota undergoes diverse changes according to the treatment response during ADA treatment. These changes provide insights into predicting treatment responses to ADA and offer new therapeutic targets for UC.

Rapid and accurate identification of Salmonella enterica serotypes Typhi and Paratyphi (A, B and C), the causal agents of enteric fever, is critical for timely treatment, case management and evaluation of health policies in low and middle-income countries where the disease still remains a serious public health problem. The present study describes the development of a multiplex assay (EFMAtyping) for simultaneous identification of pathogens causing typhoid and paratyphoid fever in a single reaction by the MeltArray approach, which could be finished within 2.5 h. Seven specific genes were chosen for differentiation of typhoidal and nontyphoidal Salmonella. All gene targets were able to be detected by the EFMAtyping assay, with expected Tm values and without cross-reactivity to other relevant Salmonella serovars. The limit of detection (LOD) for all gene targets was 50 copies per reaction. The LOD reached 10²-10³ CFU/ml for each pathogen in simulated clinical samples. The largest standard deviation value for mean Tm was below 0.5 °C. This newly developed EFMAtyping assay was further evaluated by testing 551 clinical Salmonella isolates, corroborated in parallel by the traditional Salmonella identification workflow, and serotype prediction was enabled by whole-genome sequencing. Compared to the traditional method, our results exhibited 100% of specificity and greater than 96% of sensitivity with a kappa correlation ranging from 0.96 to 1.00. Thus, the EFMAtyping assay provides a rapid, high throughput, and promising tool for public health laboratories to monitor typhoid and paratyphoid fever.

Background: Recently, the oral oncobacterium Fusobacterium nucleatum (F. nucleatum), has been linked with ulcerative colitis (UC). Here, we aim to investigate whether Fecal Microbiota Transplantation (FMT) can alleviate UC by restoring gut microbiota and eliminating oral-derived F. nucleatum and virulence factor fadA.

Method: C57BL/6J mice were randomly divided into a healthy control group (HC), Dextran Sulfate Sodium group (DSS), oral inoculation group (OR), upper FMT group (UFMT), and lower FMT group (LFMT). Disease activity index, body weight, survival rate, and histopathological scores were used to measure the severity of colitis. The function of the intestinal mucosal barrier was evaluated by performing immunohistochemical staining of the tight junction protein Occludin. Real-time PCR was used to assess the relative abundance of the nusG gene and the virulence gene fadA. Cytokine levels were detected by ELISA. Full-length sequencing of 16S rRNA was used to analyze the changes and composition of gut microbiota.

Findings: Oral incubation of F. nucleatum further exacerbated the severity of colitis and gut dysbiosis. Peptostreptococcaceae, Enterococcaceae, and Escherichia coli were significantly enriched in OR mice. However, LFMT mice showed an obvious decrease in disease activity and were more effective in restoring gut microbiota and eliminating F. nucleatum than UFMT mice. Bacteroidota, Lachnospiraceae, and Prevotellaceae were mainly enriched bacteria in LFMT mice. In addition, Genera such as Lactobacillus, Allobaculum, and Bacteroidales were found negative correlation with TNF-α, IL-1β, and IL-6. Genera like Romboutsia, Escherichia Shigella, Enterococcus, and Clostridium were found positively correlated with TNF-α, IL-1β, and IL-6.

Conclusions: Oral incubation of F. nucleatum further exacerbates the severity and dysbiosis in DSS-induced colitis mice. Besides, lower tract FMT can ameliorate colitis by restoring the gut microbiota diversity and eliminating F. nucleatum and virulence factor fadA.

Vibrio vulnificus, a significant marine pathogen, undergoes opaque (Op)-translucent (Tr) colony switching based on whether capsular polysaccharide (CPS) is produced. CPS phase variation is sometime accompanied by genetic variation or down-regulation of particular genes, such as wzb. In addition, CPS prevents biofilm formation and is important to the virulence of V. vulnificus. However, the extent to which there is a difference in gene expression between Tr and Op colonies and the impact of CPS phase variation on other behaviors of V. vulnificus remain unknown. In this work, the data have shown that CPS phase variation of V. vulnificus is affected by incubation time. Tr and Op strains exhibited similar growth rates. However, Tr strains had enhanced biofilm formation capacities but reduced swimming motility compared to Op strains. The RNA-seq assay revealed 488 differentially expressed genes, with 214 downregulated and 274 upregulated genes, between Tr and Op colonies. Genes associated with Tad pili and CPS were downregulated, whereas those involved in flagellum were upregulated, in Tr colonies compared with Op colonies. In addition, 9 putative c-di-GMP metabolism-associated genes and 28 genes encoding putative regulators were significantly differentially expressed, suggesting that CPS phase variation is probably strictly regulated in V. vulnificus. Moreover, 8 genes encoding putative porins were also differentially expressed between the two phenotypic colonies, indicating that bacterial outer membrane was remodeled during CPS phase variation. In brief, this work highlighted the gene expression profiles associated with CPS phase variation, but more studies should be performed to disclose the intrinsic mechanisms in the future.