Background:Faecalibacterium prausnitzii( Fp) is one of the most abundant bacterium in human intestinal microbiota,and is closely correlated with the process of colitis-associated colorectal cancer(CAC). Aims:To observe the effect of Fp on CAC,and investigate the possible mechanism. Methods:The model of CAC was induced by azoxymethane (AOM)and dextran sodium sulfate( DSS). Fifty-two C57BL/ 6J mice were randomly divided into 4 groups:group A (AOM + DSS),group B(AOM + DSS + Fp),group C(AOM + DSS + Fp supernatant)and group D(control group). All the mice were sacrificed on day 92. DAI was assessed,serum levels of TNF-α and IL-10 were determined by ELISA. HE staining was used to examine the grade of tumor. Expressions of VEGF,COX-2,NF-κB in tumor tissue were measured by immunohistochemistry. Results:The tumorigenesis rates of group A,B,C were 100% ,100% and 77. 8% ,respectively;mainly were high-grade intraepithelial neoplasia. The tumor load in group A was significantly higher than that in group B (P < 0. 01),and the spleen index in group B was significantly higher than that in group C(P < 0. 01). Serum level of TNF-α was significantly lower(P < 0. 05)and IL-10 was significantly higher(P < 0. 05)in group A than that in group B. No significant differences in expressions of VEGF,COX-2,NF-κB were found among group A,B and C. Conclusions:Fp had no obvious effect on the occurrence rate of CAC,and Fp supernatant could decrease the incidence of CAC in mice. Fp and its supernatant could reduce the tumor load via regulating the expressions of TNF-α,IL-10.

Objective To investigate the influence of FOXP 3 expression in pancreatic carcinoma cells (PCCs) on the maturation and immunologic function of dendritic cells (DCs).Methods The siRNA sequences targeting FOXP3 gene (siRNA-FOXP3) and negative control siRNA (siRNA-NC) were specifically designed and transfected into PCCs , then the level of IL-10 and TGF-β1 of culture supernatant were detected by ELISA.The supernatants of pancreatic carcinoma cell transfected by FOXP 3-siRNA were collected , then it was mixed with GM-CSF and IL-4 to induce the differentiation of DCs .Flow cytometric analysis were used to measure the expression of surface markers CD 86 , CD80 , HLA DR on DCs which were treated with supernatants . The levels of IL-12p70, IFN-γin supernatants were detected by ELISA .The DCs were co-cultured with T lymphocytes, and then the lymphocytes proliferation and cytoxicity were analyzed by CCK -8 assays.Results Compared with PANC1 with siRNA-NC transfection, PANC1 with siRNA-FOXP3 transfection had a decreased expression of IL-10, TGF-β1 [(8.93 ±3.06)ng/L vs (26.60 ±5.57)ng/L;(2 544 ±78)ng/L vs (2 856 ± 92)ng/L], the positive expression rate of CD86, HLA DR in DCs cultured in the medium containing the supernatants of the pancreatic carcinoma cell transfected by siRNA-FOXP3 was significantly increased [(28.10 ±3.11)%vs (13.90 ±0.42)%;(66.15 ±4.17)%vs (43.15 ±3.32)%], the expression of IL-12p70, IFN-γwas significantly increased [(52.75 ±7.89)ng/L vs (26.14 ±4.50)ng/L, (898.43 ±88.82) ng/L vs (412.76 ±24.68) ng/L], after co-culture with lymphocytes at ratios of 1:5, 1:10, 1:20, the proliferation was significantly increased [(95.27 ±3.80)% vs (71.77 ±5.70)%, (78.97 ±5.73)% vs (52.30 ±8.72)%, (57.60 ±4.36)% vs (43.73 ±6.01)%], and the cytoxicity of CTL to PANC1 cells with 1:20, 1:40 co-culture was significantly increased [(28.44 ±5.20)% vs (8.82 ±2.29)%, (40.85 ± 5.15)% vs (17.38 ±4.86)%], and the difference between the two groups was statistically significant (P<0.05).Conclusions FOXP3 expression in PCCs can inhibit the maturation and immunologic function of DCs.

To evaluate the diagnostic value of endoscopic ultrasonography (EUS) for small common bile duct stones, 60 patients diagnosed as having suspected common bile duct stones who were hospitalized in Zhongda Hospital, Southeast University from January 2018 to July 2021 were selected. All patients were examined by EUS and magnetic resonance cholangiopancreatography (MRCP) during the same hospitalization. The results of endoscopic retrograde cholangiopancreatography, laparotomy or laparoscopic common bile duct exploration were adopted as the golden standard. The diagnostic results of EUS and MRCP were compared with the golden standard, and the sensitivity, specificity, positive predictive value and negative predictive value of the two methods were calculated. Among the 60 patients, 46 cases were confirmed as having common bile duct stones, 43 cases were diagnosed accurately by EUS and 35 cases by MRCP. Fourteen patients were confirmed as having no common bile duct stones, and the diagnosis was accurate in 12 cases by EUS and 13 cases by MRCP. The sensitivity of EUS was significantly higher than that of MRCP [93.48% (43/46) VS 76.09% (35/46), χ2=4.128, P=0.042]. There were 45 cases with diameter ≤1.0 cm, of which 42 cases were diagnosed by EUS and 34 by MRCP (diagnostic accuracy 93.33% VS 75.56%, χ2=4.145, P=0.042). There were 39 cases with diameter ≤0.8 cm, of which 36 cases were diagnosed by EUS and 28 by MRCP (diagnostic accuracy 92.31% VS 71.79%, χ2=4.266, P=0.039). There were 26 cases with diameter ≤0.5 cm, of which 24 cases were diagnosed by EUS and 16 by MRCP (diagnostic accuracy 92.31% VS 61.54%, χ2=5.038, P=0.021). EUS has obvious advantages in the diagnosis of common bile duct stones, and the accuracy of EUS is not affected by the size of stone. As a consequence, EUS should be performed in patients with high clinical suspicion of common bile duct stones but negative MRCP result.