Genetic diversity, biofilm formation, and Vancomycin resistance of clinical Clostridium innocuum isolates.

BACKGROUND: Clostridium innocuum, previously considered a commensal microbe, is a spore-forming anaerobic bacterium. C. innocuum displays inherent resistance to vancomycin and is associated with extra-intestinal infections, antibiotic-associated diarrhea, and inflammatory bowel disease. This study seeks to establish a multilocus sequence typing (MLST) scheme to explore the correlation between C. innocuum genotyping and its potential pathogenic phenotypes. METHODS: Fifty-two C. innocuum isolates from Linkou Chang Gung Memorial Hospital (CGMH) in Taiwan and 60 sequence-available C. innocuum isolates from the National Center for Biotechnolgy Information Genome Database were included. The concentrated sequence of housekeeping genes in C. innocuum was determined by amplicon sequencing and used for MLST and phylogenetic analyses. The biofilm production activity of the C. innocuum isolates was determined by crystal violet staining. RESULTS: Of the 112 C. innocuum isolates, 58 sequence types were identified. Maximum likelihood estimation categorized 52 CGMH isolates into two phylogenetic clades. These isolates were found to be biofilm producers, with isolates in clade I exhibiting significantly higher biofilm production than isolates in clade II. The sub-inhibitory concentration of vancomycin seemed to minimally influence biofilm production by C. innocuum isolates. Nevertheless, C. innocuum embedded in the biofilm structure demonstrated resistance to vancomycin treatments at a concentration greater than 256 µg/mL. CONCLUSIONS: This study suggests that a specific genetic clade of C. innocuum produces a substantial amount of biofilm. Furthermore, this phenotype assists C. innocuum in resisting high concentrations of vancomycin, which may potentially play undefined roles in C. innocuum pathogenesis.

Association between coronary artery disease and incident cancer risk: a systematic review and meta-analysis of cohort studies.

Objective: Coronary artery disease (CAD) and cancer are the two leading causes of death worldwide. Evidence suggests the existence of shared mechanisms for these two diseases. We aimed to conduct a systematic review and meta-analysis to investigateassociation between CAD and incident cancer risk. Methods: We searched Cochrane, PubMed, and Embase from inception until October 20, 2021, without language restrictions. Observational cohort studies were used to investigate the association between CAD and incident cancer risk. Using random-effects models, the odds ratio (OR) and 95% confidence interval (CI) were calculated. We utilized subgroup and sensitivity analyses to determine the potential sources of heterogeneity and explore the association between CAD and specific cancers. This study was conducted under a pre-established, registered protocol on PROSPERO (CRD42022302507). Results: We initially examined 8,533 articles, and included 14 cohort studies in our review, 11 of which were eligible for meta-analysis. Patients with CAD had significantly higher odds of cancer risk than those without CAD (OR = 1.15, 95% CI = [1.08-1.22], I2 = 66%). Subgroup analysis revealed that the incident cancer risk was significantly higher in both sexes and patients with CAD with or without myocardial infarction. Sensitivity analysis revealed that the risk remained higher in patients with CAD even after >1 year of follow-up (OR = 1.23, 95% CI = [1.08-1.39], I2 = 76%). Regarding the specific outcome, the incident risk for colorectal and lung cancers was significantly higher (OR = 1.06, 95% CI = [1.03-1.10], I2 = 10%, and OR = 1.36, 95% CI = [1.15-1.60], I2 = 90%, respectively) and that for breast cancer was lower (OR = 0.86, 95% CI = [0.77-0.97], I2 = 57%) in patients with CAD than in those without CAD. Conclusion: CAD may be associated with incident cancer risk, particularly for lung and colorectal cancers, in men and women as well as patients with or without myocardial infarction. Early detection of new-onset cancer and detailed cancer surveillance programs should be implemented in patients with CAD to reduce cancer-related morbidity and mortality.