Objective To evaluate the incidence of surgical site infection (SSI)in patients with colorectal cancer and identify the risk factors of SSI.Methods A total of 392 patients who underwent colorectal cancer resection at the First Affiliated Hospital of Chongqing Medical University between September 2012 and September 2013 were included and analyzed in terms of the presence of SSI.SSI risk factors were identified by both univariate and multivariate analysis.Results The overall incidence of SSI was 23.0%.Univariate analysis showed that duration of operation above 75 th percentile,colostomy,surgical procedure, type of surgical incision,and American Society of Anesthesiologists (ASA)score were significantly associated with higher risk of SSI (P <0.05).Binary logistic regression suggested that duration of operation above 75 th percentile (P = 0.000,OR =3.017),colostomy (P =0.008,OR=2.642),Contaminated incision (P =0.016,OR=3.311)and laparoscopic surgery (P =0.016,OR=0.523)were significantly different in terms of presence or absence of SSI.Conclusions Duration of operation above 75th percentile,colostomy and contaminated incision are independent risk factors,while laparoscopic surgery is a protective factor for SSI in patients with colorectal cancer.

Objective: To investigate the changes of microorganisms and metabolites in joint effusion of patients with Rheumatoid arthritis(RA), Osteoarthritis(OA) and Urarthritis(UA). To provide new ideas for the study of the effect of microbiota on the pathogenesis of arthritis. Methods: Joint effusion samples were collected from 20 patients with RA, 20 patients with OA, and 20 patients with UA. 16S rRNA gene sequencing and untargeted ultra-high performance Liquid chromatography-mass spectrometry(LC-MS) were used to explore the differences in microorganisms and metabolites among the three groups. Pearson correlation analysis was used to detect the correlation between effusion microbiota and metabolites. Results: There were differences in microbial diversity and microbiota composition among the three groups. Combined with VIP>1 from OPLS-DA andP<0.05 from two-tailed Students t-test, 45 differential metabolites(Between RA and OA groups), 38 differential metabolites(Between UA and OA groups) and 16 differential metabolites(Between RA and UA groups), were identified. GO analysis and KEGG pathway analysis showed that the differential metabolic pathways among the three groups were mainly concentrated in citric acid cycle(TCA cycle), nucleotide metabolism, amino acid metabolism and glycolysis pathway. Correlation analysis of joint effusion microbiota and metabolites suggested that bacteria enriched in the three groups of joint effusion, such asPrevotella,Clostridium ruminosus,Prevotellaceae＿UCG-001, were related to many key metabolites such as lysozyme, uric acid, glucose, and L-glutamine. Conclusion This study shows that there are a variety of bacterial flora in joint cavity effusion of RA, OA, and UA patients, and the differential metabolites produced by them are involved in the pathogenesis of the three types of arthritis by affecting a variety of metabolic pathways.