Effect of Hydrotalcite on Indometacin-Induced Gastric Injury in Rats.

BACKGROUND AND AIMS: Hydrotalcite plays an important role in the therapy of gastric ulcer induced by nonsteroidal anti-inflammatory drugs (NSAIDs), but little is known about the mechanism. We designed two experiments to study the preventive and curative effects of hydrotalcite on NSAIDs-related gastric injury in rats and to investigate the relationship between the protective and curative mechanism of hydrotalcite and the secretion of epidermal growth factor (EGF)/prostaglandin E2 (PGE2). METHODS: Two experiments were separately designed to evaluate the preventive and curative effects of hydrotalcite. A total of 25 male rats and 25 female rats were randomly divided into five groups (vehicle group, model group, omeprazole group, hydrotalcite group, and ranitidine group) in each experiment. Rats were treated with indomethacin by gavage to build the model of acute gastric mucosal injury. The concentrations of EGF and PGE2 in blood specimens and mucosal injury indexes by gross inspection were measured and an immunohistochemical technique was also employed to test the levels of EGF, cyclooxygenase-1 (COX-1), and cyclooxygenase-2 (COX-2) in gastric mucosa. RESULTS: Comparing with model group in both preventive and curative experiments, hydrotalcite decreased the gastric injury in the mucosa of stomach significantly (7±4.5 vs. 16±11.25, 1.5±2 vs. 2.5±6; P<0.01, P<0.05). The levels of EGF and PGE2 in blood serum were markedly higher in hydrotalcite group than that in model group and ranitidine group in preventive experiment (574.39±34.28 vs. 486.22±41.73, 488.07±24.44; P<0.01, P<0.01). The expression levels of COX-2 in gastric mucosa were also higher in hydrotalcite group than that in model group in both preventive and therapeutic experiments (12±4 vs. 9±6, 14±7 vs. 9±4; P<0.01, P<0.05). CONCLUSIONS: Hydrotalcite promotes gastric protection and healing via several mechanisms, including increased levels of PGE2 in blood serum, activation of EGF, and antagonising the inhibition of cyclooxygenase (COX) caused by NSAIDs.

Evaluation of narrow-band imaging in the diagnosis of colorectal lesions and learning curve / 中国内镜杂志

Objective To evaluate the usefulness of narrow-band imaging with magnification in differentiating colorectal lesions, and assess for a learning curve, to gave help for the clinician, who want to carry out the technique. Method We retrospectively analyzed the clinical data of 289 patients who underwent NBI combined with magnification by four endoscopic physician, from June, 2015 to June, 2016, all the lesions were biopsied, endoscopic treatment or postoperative pathology and pathological examination, and the Sano classification control. All lesions were divided into three groups according to the NBI combined with magnifying endoscopy, these three sets included both lesions requiring endoscopic treatment (e.g. target lesions) and lesions that were not, or could not be, treated by endoscopy (e.g. nontarget lesions). Each physician examined the target or non-target lesion reached 15 cases as a group. By assessing the diagnostic accuracy of the four physicians for each group of lesions, an associated learning curve of NBI combined with magnifying endoscopy was developed. Result In 289 patients, 372 lesions were found by colonoscopy. NBI combined with magnifying endoscopy was 95.1%, 98.0% and 92.0%, respectively, in the identification of tumor and non-neoplastic lesions. The accuracy of the diagnosis of target and non-target lesions was significantly higher in group 2 than in group 1 [81.7% vs 95.1% (P = 0.010) and 71.7% vs 93.4% (P = 0.000)]. There was no significant difference in the diagnostic accuracy between group 2 and group 3 (P = 0.984 and P = 0.117). Conclusion It is very useful to use narrow-band imaging and Sano CP analysis in the differential diagnosis of colorectal lesions. The endoscopists who had never used NBI or no knowledge of NBI can have effective and stable diagnostic accuracy after using NBI with magnification to diagnose 15 target and non-target lesions respectively.

Evaluation of narrow-band imaging in the diagnosis of colorectal lesions and learning curve / 中国内镜杂志

Objective To evaluate the usefulness of narrow-band imaging with magnification in differentiating colorectal lesions, and assess for a learning curve, to gave help for the clinician, who want to carry out the technique. Method We retrospectively analyzed the clinical data of 289 patients who underwent NBI combined with magnification by four endoscopic physician, from June, 2015 to June, 2016, all the lesions were biopsied, endoscopic treatment or postoperative pathology and pathological examination, and the Sano classification control. All lesions were divided into three groups according to the NBI combined with magnifying endoscopy, these three sets included both lesions requiring endoscopic treatment (e.g. target lesions) and lesions that were not, or could not be, treated by endoscopy (e.g. nontarget lesions). Each physician examined the target or non-target lesion reached 15 cases as a group. By assessing the diagnostic accuracy of the four physicians for each group of lesions, an associated learning curve of NBI combined with magnifying endoscopy was developed. Result In 289 patients, 372 lesions were found by colonoscopy. NBI combined with magnifying endoscopy was 95.1%, 98.0% and 92.0%, respectively, in the identification of tumor and non-neoplastic lesions. The accuracy of the diagnosis of target and non-target lesions was significantly higher in group 2 than in group 1 [81.7% vs 95.1% (P = 0.010) and 71.7% vs 93.4% (P = 0.000)]. There was no significant difference in the diagnostic accuracy between group 2 and group 3 (P = 0.984 and P = 0.117). Conclusion It is very useful to use narrow-band imaging and Sano CP analysis in the differential diagnosis of colorectal lesions. The endoscopists who had never used NBI or no knowledge of NBI can have effective and stable diagnostic accuracy after using NBI with magnification to diagnose 15 target and non-target lesions respectively.

Diagnostic performance of magnifying narrow-band imaging for early gastric cancer: A meta-analysis.

AIM: To investigate the performance of magnifying endoscopy with narrow-band imaging (ME-NBI) in the diagnosis of early gastric cancer (EGC). METHODS: Systematic literature searches were conducted until February 2014 in PubMed, EMBASE, Web of Science, Ovid, Scopus and the Cochrane Library databases by two independent reviewers. Meta-analysis was performed to calculate the pooled sensitivity, specificity and diagnostic odds ratio and to construct a summary receiver operating characteristic (ROC) curve. Subgroup analyses were performed based on the morphology type of lesions, diagnostic standard, the size of lesions, type of assessment, country and sample size to explore possible sources of heterogeneity. A Deeks' asymmetry test was used to evaluate the publication bias. RESULTS: Fourteen studies enrolling 2171 patients were included. The pooled sensitivity, specificity and diagnostic odds ratio for ME-NBI diagnosis of EGC were 0.86 (95%CI: 0.83-0.89), 0.96 (95%CI: 0.95-0.97) and 102.75 (95%CI: 48.14-219.32), respectively, with the area under ROC curve being 0.9623. Among the 14 studies, six also evaluated the diagnostic value of conventional white-light imaging, with a sensitivity of 0.57 (95%CI: 0.50-0.64) and a specificity of 0.79 (95%CI: 0.76-0.81). When using "VS" (vessel plus surface) ME-NBI diagnostic systems in gastric lesions of depressed macroscopic type, the pooled sensitivity and specificity were 0.64 (95%CI: 0.52-0.75) and 0.96 (95%CI: 0.95-0.98). For the lesions with a diameter less than 10 mm, the sensitivity and specificity were 0.74 (95%CI: 0.65-0.82) and 0.98 (95%CI: 0.97-0.98). CONCLUSION: ME-NBI is a promising endoscopic tool in the diagnosis of early gastric cancer and might be helpful in further target biopsy.