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991.
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Background

The maximal effect of proton pump inhibitors (PPI) is reported to take 5 days. However, most current protocols start PPI on the day of gastric endoscopic submucosal dissection (ESD).

Aims

We aimed to evaluate the benefit of 5 days pretreatment with oral PPI before ESD to prevent bleeding.

Methods

This was a prospective randomized controlled trial. Patients were administered oral rabeprazole 20 mg or placebo twice daily for 5 days before ESD. Intravenous pantoprazole 40 mg was administered 2 h before ESD and at postprocedure day 1, and then oral rabeprazole 20 mg was administered once daily. Follow-up endoscopy was performed on days 1 and 30. Forty-eight-hour measurement of intragastric pH was performed in 26 patients. The primary endpoint was major bleeding related to ESD.

Results

One-hundred and twenty patients were enrolled. Of these, 45 in the pretreatment and 53 in the placebo group were analyzed. Each group had three cases of major bleeding. There were no significant differences in the ulcer healing rate. Intragastric pH percentage times greater than 4, 5, and 6 were 86.61 ± 19.45 %, 83.30 ± 22.06 %, and 76.86 ± 25.35 %, respectively, in the pretreatment and 85.54 ± 19.45 %, 84.08 ± 27.11 %, and 81.53 ± 27.81 %, respectively, in the placebo group, without significant differences.

Conclusions

Preprocedural administration of rabeprazole offers no additional benefit over postprocedural administration alone in preventing major bleeding after gastric ESD.  相似文献   
994.

Background

Distinguishing deep submucosa (SM) from superficial SM cancer in large sessile and flat colorectal polyps (>2 cm) is crucial in making the most appropriate therapeutic decision. We evaluated the additional role of magnifying narrow-band imaging (NBI) and magnifying chromoendoscopy (MCE) in assessing the depth of invasion in large sessile and flat polyps in comparison to morphological evaluation performed by experienced endoscopists.

Methods

From May 2011 to December 2011, a total of 85 large sessile and flat polyps were analyzed. Endoscopic features of the polyps were independently evaluated by experienced endoscopists. Subsequently, the polyps were observed using magnifying NBI and MCE.

Results

A total of 58 intramucosal lesions and 27 SM cancers (five superficial and 22 deep) were identified. The diagnostic accuracy of the experienced endoscopists, NBI, and MCE were 92.9, 90.6, and 89.4 %, respectively, for deep SM cancer. In combination with NBI or MCE, the diagnostic accuracy of the experienced endoscopists did not change significantly for deep SM cancer, with an accuracy of 95.3 % for both NBI and MCE.

Conclusions

Conventional colonoscopy can differentiate superficial from deep SM cancers with an accuracy of as high as 92.9 % in large sessile and flat polyps. Further diagnostic strategies are required in order to precisely assess the depth of invasion, especially in large colorectal polyps.  相似文献   
995.

Background

Biliary decompression with antibiotic therapy is the mainstay treatment for acute cholangitis with bacteremia. A few studies have been conducted to investigate the optimal duration and route of antibiotic therapy in biliary tract infection with bacteremia.

Methods

Patients with acute cholangitis with bacteremia who achieved successful biliary drainage were randomly assigned to an early oral antibiotic switch group (group A, n = 29) and a conventional intravenous antibiotics group (group B, n = 30). Patients were discharged when they were afebrile over 2 days after oral antibiotic switch and showed consecutive improvement in the laboratory index. They were followed up and assessed at 30 days after diagnosis to evaluate the eradication of bacteria, recurrence of acute cholangitis, and 30-day mortality rate.

Results

There were no statistically significant differences between the two groups in baseline characteristics, clinical and laboratory index, severity of acute cholangitis, bacteria isolated from blood cultures, and clinical outcomes. The rate of eradication of bacteria was 93.1 % in group A and 93.3 % in group B, respectively (p = 0.97). Using non-inferiority tests, the rate of eradication of bacteria in group A was not inferior to that in group B (95 % CI ?0.13 to 0.14, p = 0.97). There was no statistically significant difference in the recurrence of acute cholangitis and a 30-day mortality rate between the two groups.

Conclusions

Early switch to oral antibiotic therapy following adequate biliary drainage for treatment of acute cholangitis with bacteremia was not inferior to conventional 10-day intravenous antibiotic therapy.  相似文献   
996.

Background

Little is known about the role of follow-up endoscopy in patients with inflammatory bowel disease (IBD).

Aim

The present study aimed to evaluate whether repeated endoscopies would be beneficial in improving outcomes of patients with IBD.

Methods

Patients who had been initially confirmed to have IBD at two tertiary hospitals in Korea were regularly followed and included in this study. The clinical impact as assessed by the presence or absence of a change in management after endoscopy and cumulative hospitalization rate was compared between two groups classified according to the presence or absence of indications.

Results

A total of 188 patients with IBD were enrolled [69 patients with Crohn’s disease (CD) and 119 with ulcerative colitis (UC)]. Of these patients, 130 underwent follow-up endoscopy (48 with CD and 82 with UC). The rate of management change was significantly higher in the group with indications for follow-up endoscopy (p = 0.001 in CD and <0.001 in UC). The presence of any indications for follow-up endoscopy was found to be a significant predictor of hospitalization risk in patients with UC (p = 0.015), but not in those with CD. However, there was no significant difference in cumulative hospitalization hazard with respect to treatment change in patients without any endoscopic indications (p = 0.561 in CD and 0.423 in UC).

Conclusions

Follow-up endoscopy might not have a significant impact on the overall clinical course and outcomes in patients with IBD. However, the presence of endoscopic indications predicts a poor clinical outcome in UC.  相似文献   
997.

Background

Endoscopic papillary large balloon dilation (EPLBD) after an endoscopic sphincterotomy (EST) is an option for endoscopic removal of large common bile duct (CBD) stones. However, risks or fear of severe adverse events remain.

Aims

Our aim was to compare the safety and efficacy of delayed EPLBD after EST with concurrent EST and EPLBD in patients with acute cholangitis by large CBD stones.

Patients and Methods

A total of sixty-eight patients with acute cholangitis from large CBD stones were enrolled in this prospective observational study. Thirty-five patients underwent concurrent EST and EPLBD at the same session (group A). Thirty-three patients underwent only EST at the first session, and EPLBD with stone removal was performed during a second session (group B). The complete stone removal rate and adverse events rate were analyzed.

Results

Both groups resulted in similar outcomes in terms of overall successful stone removal (100 % in both groups) and the use of additional lithotripsy (22.9 % in group A and 24.2 % in group B). Six patients (17.1 %) in group A had procedural-related adverse events including one patient with death by perforation, one with significant bleeding, and four with pancreatitis, including one moderate grade. However, there was no procedure-related complication in group B (p < 0.05).

Conclusions

Delayed EPLBD after EST may reduce complications associated with EPLBD and extraction of large bile duct stones in patients with acute cholangitis.  相似文献   
998.
999.
1000.
Tacrolimus is one of the most commonly used immunosuppressive agents in animal models of transplantation. However, in these models, oral administration is often problematic due to the lowered compliance associated with highly invasive surgery and due to malabsorption in the intestinal tract. Therefore, we carried out a study to determine the pharmacokinetics of tacrolimus after intramuscular (IM) injection and to determine the optimal IM dosing regimens in primate models. Six male cynomolgus monkeys (Macaca fascicularis) were used in the study. Doses of 0.1 mg/kg and 5 mg were administered via IM injection and oral administration, respectively, once to determine single-dose pharmacokinetics and once daily for 5 days to determine multiple-dose pharmacokinetics. According to pharmacokinetic model estimates, the inter- and intra-individual variabilities in bioavailability following IM injection were remarkably reduced compared with those following oral administration. Monte Carlo simulations revealed that Cpeak, Ctrough and AUC would also have less variability following IM injection compared with oral administration. In this study, we found that the pharmacokinetic characteristics of tacrolimus were more constant following IM injection compared with oral administration. These results suggest that IM injection can be an alternative route of administration fin non-human primate model studies.  相似文献   
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