Positive correlation between latent Epstein-Barr virus infection and severity of illness in inflammatory bowel disease patients

BACKGROUND Emerging studies indicate the critical involvement of microorganisms,such as Epstein-Barr virus(EBV),in the pathogenesis of inflammatory bowel disease(IBD).Immunosuppressive therapies for IBD can reactivate latent EBV,complicating the clinical course of IBD.Moreover,the clinical significance of EBV expression in B lymphocytes derived from IBD patients’intestinal tissues has not been explored in detail.AIM To explore the clinical significance of latent EBV infection in IBD patients.METHODS Latent EBV infection was determined by double staining for EBV encoded RNA and CD20 in colon specimens of 43 IBD patients who underwent bowel resection.Based on the staining results,the patients were divided into two groups,according to their latent EBV infection states-negative(n=33)and positive(n=10).Illness severity of IBD were assigned according to Crohn’s disease activity index(ulcerative colitis)and Mayo staging system(Crohn’s disease).The clinicpathological data were analyzed between the two different latent EBV groups and also between the mild-to-moderate and severe disease groups.RESULTS Systolic pressure(P=0.005),variety of disease(P=0.005),the severity of illness(P=0.002),and pre-op corticosteroids(P=0.025)were significantly different between the EBV-negative and EBV-positive groups.Systolic pressure(P=0.001),variety of disease(P=0.000),pre-op corticosteroids(P=0.011)and EBV infection(P=0.003)were significantly different between the mild-to-moderate and severe disease groups.CONCLUSION IBD patients with latent EBV infection may manifest more severe illnesses.It is suggested that the role of EBV in IBD development should be further investigated,latent EBV infection in patients with serious IBD should be closely monitored,and therapeutic course should be optimized.

Oleanolic acid and ursolic acid inhibit proliferation in transformed rat hepatic oval cells

AIM: To investigate H2O2-induced promotion proliferation and malignant transformation in WB-F344 cells and anti-tumor effects of ursolic acid(UA) and oleanolic acid(OA). METHODS: WB-F344 cells were continuously exposed to 7 x 10-7mol/L H2 O2 for 21 d. Observations of cell morphology, colony formation rates, flow cytometric analysis of cell cycle changes and aneuploidy formation indicated that H2 O2 was able to induce malignant transformation of WB-F344 cells. We treated malignantly transformed WB-F344 cells with 4 μmol/L OA or 8 μmol/L UA for 72 h and analyzed the cell cycle distribution by flow cytometry. RESULTS: MTT assay showed that 7 x 10-7mol/L H2 O2 decreased G1 phase subpopulation from 73.8% to 49.6% compared with the control group, and increased S phase subpopulation from 14.5% to 31.8%(P < 0.05 vs control group). Cell morphology showed that nucleus to cytoplasm ratio increased, many mitotic cells, prokaryotes and even tumor giant cells were shown in H2 O2-induced WB-F344 cells. Fluorescence activated cell sorting analysis showed that WB-F344 cell aneuploidy increased to 12% following H2 O2 treatment. Flow cytometric analysis of the transformed WB-F344 cells following treatment with OA(4 μmol/L) and UA(8 μmol/L) showed that OA increased G1 subpopulation to 68.6%, compared to 49.7% in unexposed cells. UA increased G1 subpopulation to 67.4% compared to 49.7% in unexposed cells(P < 0.05 vs H2 O2 model group). CONCLUSION: H2O2 causes the malignant transformation of WB-F344 cells. OA and UA exert anti-tumor effects by inhibiting the proliferation in malignantly transformed WB-F344 cells.

Hydrogen embrittlement of X80 pipeline steel in H2S environment: Effect of hydrogen charging time, hydrogen-trapped state and hydrogen charging–releasing–recharging cycles

This study investigated the susceptibility of X80 pipeline steel to hydrogen embrittlement given different hydrogen pre-charging times and hydrogen charging–releasing–recharging cycles in H2S environment.The fracture strain of the steel samples decreased with increasing hydrogen pre-charging time;this steel degradation could almost be recovered after diffusible hydrogen was removed when the hydrogen pre-charging time was<8 d.However,unrecoverable degeneration occurred when the hydrogen pre-charging time extended to 16–30 d.Moreover,nanovoid formation meant that the hydrogen damage to the steel under intermittent hydrogen pre-charging–releasing–recharging conditions was more serious than that under continuous hydrogen pre-charging conditions.This study illustrated that the mechanical degradation of steel is inevitable in an H2S environment even if diffusible hydrogen is removed or visible hydrogen-induced cracking is neglected.Furthermore,the steel samples showed premature fractures and exhibited a hydrogen fatigue effect because the repeated entry and release of diffusible hydrogen promoted the formation of vacancies that aggregated into nanovoids.Our results provide valuable information on the mechanical degradation of steel in an H2S environment,regarding the change rules of steel mechanical properties under different hydrogen pre-charging times and hydrogen charging–releasing–recharging cycles.