Dynamic modeling and characteristic analysis of piezoelectric rudder actuator.

In this note, dynamic equations of the piezoelectric rudder actuator are established using a numerical method, and the dynamic characteristics are analyzed. A simulation is performed using finite element software to verify the validity of the theory. The results show that an increase in axial force has significant amplification effects on the static displacement output of the bimorph and its rudder actuator, and the axial stiffness of the piezoelectric bimorph is evidently nonlinear against larger axial force. The response time of the rudder actuator is less affected by the axial force and remains in the order of milliseconds under the axial force of 0.85 times the buckling critical load.

Combination of doxorubicin liposomes with left atrial appendage radiofrequency catheter ablation to reduce post-ablation recovery of electrical conduction.

AIMS: To determine whether use of radiofrequency catheter ablation (RFCA) combined with intravenously administered liposomal doxorubicin (L-DOX) facilitates a reduction in the recovery of post-ablation electrical conduction. METHODS: Circumferential ablation was performed on the epicardial surface of the left atrial appendage (LAA) in New Zealand White rabbits, and L-DOX was then administered intravenously. Fluorescence spectrophotometry was used to assess reagent bio-distribution, while Western blots and immunohistochemistry were used to assess the localization of the apoptotic markers Bcl-2, Bax, and cleaved CASP3 in the LAA. Liver, kidney, and cardiac functions were also measured to evaluate the safety of this approach. RESULTS: At 1 week and 1 month after RFCA, a pacing electrocardiogram could not be detected in most of the rabbits that had received the combined RFCA and L-DOX therapy. L-DOX began to target the LAA on the second day after RFCA. L-DOX treatment increased the apoptosis of cardiomyocytes in the regions peripheral to the necrotic area induced by RFCA. Doxorubicin had some effect on liver and kidney function, but these effects were reversible and did not affect survival. CONCLUSION: The present results provide evidence that L-DOX treatment can reduce the recovery of electrical conduction after RFCA therapy owing to L-DOX-induced apoptosis of cardiomyocytes in the ablated area and the proximal transition zone of the LAA.

Fecal Calprotectin for predicting Relapse and Activity in Patients with Crohn's Disease: A Meta-analysis.

AIMS: We aimed to perform a meta-analysis of the predictive capacity of fecal calprotectin (FC) in activity and relapse of Crohn's disease (CD). MATERIALS AND METHODS: MEDLINE, EMBASE, and the Cochrane Library databases were searched systematically. Pooled sensitivity, specificity, and other diagnostic indices were evaluated. RESULTS: A total of 1,252 CD patients from 18 different studies were analyzed. The pooled sensitivity and specificity of FC at a cutoff value of 50 µg/g to predict activity of CD were 0.91 [95% confidence interval (CI): 0.87-0.95] and 0.47 (95% CI: 0.35-0.59) respectively. The pooled sensitivity and specificity of FC at a cutoff value of larger than 150 µg/g to monitor relapse of CD was 0.75 (95% CI: 0.67-0.82) and 0.71 (95% CI: 0.66-0.76) respectively. The area under the summary receiver operating characteristic (SROC) curve of FC for detecting CD activity was 0.78 (50 µg/g), 0.88 (100 µg/g), 0.85 (>150 µg/g), and the diagnostic odds ratio (DOR) was 10.21 (50 µg/g), 10.20 (100 µg/g), 11.68 (>150 µg/g) respectively. CONCLUSION: As a simple and noninvasive marker, FC is useful to predict the activity and relapse in CD patients, and the capacity of FC to predict CD activity was superior to its application in monitoring relapse of CD. HOW TO CITE THIS ARTICLE: Zhuge Y, Huang Q-P, Li Q, Wang J-S. Fecal Calprotectin for predicting Relapse and Activity in Patients with Crohn's Disease: A Meta-analysis. Euroasian J Hepato-Gastroenterol 2016;6(2):116-124.

Severe Henoch-Schönlein purpura with infliximab for ulcerative colitis.

Infliximab (IFX) is an anti-tumor necrosis factor chimeric antibody that is effective for treatment of autoimmune disorders such as Crohn's disease and ulcerative colitis (UC). IFX is well tolerated with a low incidence of adverse effects such as infections, skin reactions, autoimmunity, and malignancy. Dermatological manifestations can appear as infusion reaction, vasculitis, cutaneous infections, psoriasis, eczema, and skin cancer. Here, we present an unusual case of extensive and sporadic subcutaneous ecchymosis in a 69-year-old woman with severe UC, partial colectomy and cecostomy, following her initial dose of IFX. The reaction occurred during infliximab infusion, and withdrawal of IFX led to gradual alleviation of her symptoms. We concluded that Henoch-Schönlein purpura, a kind of leukocytoclastic vasculitis, might have contributed to the development of the bruising. Although the precise mechanisms of the vasculitis are still controversial, such a case highlights the importance of subcutaneous adverse effects in the management of UC with IFX.

Meta-analysis of the efficacy of probiotics in Helicobacter pylori eradication therapy.

AIM: To evaluate the role of probiotics in the standard triple Helicobacter pylori therapy. METHODS: In this meta-analysis, we investigated the efficacy of probiotics in a standard triple H. pylori therapy in adults. Searches were mainly conducted in MEDLINE/PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Fourteen studies met our criteria, and the quality of these studies was assessed using the Jadad scale. We used STATA version 12.0 to extract data and to calculate the odds ratios (ORs), which are presented with the corresponding 95% confidence intervals (CIs). The data are presented as forest plots. RESULTS: The pooled ORs for the eradication rates calculated by intention-to-treat analysis and per-protocol analysis in the probiotic group vs the control group were 1.67 (95%CI: 1.38-2.02) and 1.68 (95%CI: 1.35-2.08), respectively, using the fixed-effects model. The sensitivity of the Asian studies was greater than that of the Caucasian studies (Asian: OR = 1.78, 95%CI: 1.40-2.26; Caucasian: OR = 1.48, 95%CI: 1.06-2.05). The pooled OR for the incidence of total adverse effects was significantly lower in the probiotic group (OR = 0.49, 95%CI: 0.26-0.94), using the random effects model, with significant heterogeneity (I (2) = 85.7%). The incidence of diarrhea was significantly reduced in the probiotic group (OR = 0.21, 95%CI: 0.06-0.74), whereas the incidence of taste disorders, metallic taste, vomiting, nausea, and epigastric pain did not differ significantly between the probiotic group and the control group. CONCLUSION: Supplementary probiotic preparations during standard triple H. pylori therapy may improve the eradication rate, particularly in Asian patients, and the incidence of total adverse effects.

Potential role of Th17 cells in the pathogenesis of inflammatory bowel disease.

The etiopathology of inflammatory bowel disease (IBD) remains elusive. Accumulating evidence suggests that the abnormality of innate and adaptive immunity responses plays an important role in intestinal inflammation. IBD including Crohn's disease (CD) and ulcerative colitis (UC) is a chronic inflammatory disease of the gastrointestinal tract, which is implicated in an inappropriate and overactive mucosal immune response to luminal flora. Traditionally, CD is regarded as a Th1-mediated inflammatory disorder while UC is regarded as a Th2-like disease. Recently, Th17 cells were identified as a new subset of T helper cells unrelated to Th1 or Th2 cells, and several cytokines [e.g. interleukin (IL)-21, IL-23] are involved in regulating their activation and differentiation. They not only play an important role in host defense against extracellular pathogens, but are also associated with the development of autoimmunity and inflammatory response such as IBD. The identification of Th17 cells helps us to explain some of the anomalies seen in the Th1/Th2 axis and has broadened our understanding of the immunopathological effects of Th17 cells in the development of IBD.