A randomized controlled trial comparing water exchange and air insufflation during colonoscopy without sedation.

OBJECTIVES: Previous studies have shown that water exchange is superior to air insufflation in attenuating insertion pain during colonoscopy. We conducted a randomized controlled trial with head-to-head comparison of these methods to assess their effectiveness in colonoscopy without sedation. METHODS: A total of 447 outpatients were randomized to either water exchange (WE) or the standard air (CO2) insufflation (AI). The primary outcome was the improvement of patient intraprocedural pain (pain score), evaluated using a questionnaire (scores 1 to 5). RESULTS: After exclusion of 44 patients from further analysis, 403 patients were analyzed. There was no difference in clinical background between the WE and AI groups. Patients in the WE group reported less intraprocedural pain than those in the AI group (2.17 ± 1.06 vs. 2.42 ± 1.03; unpaired t test, p = 0.021). We divided the cases into two groups, more or less painful colonoscopy, based on age, body mass index, use of anti-peristaltic drugs or not, and physician's experience. In less painful colonoscopy, the WE method could reduce pain effectively but its effect was limited in the more painful group. CONCLUSION: WE is superior to AI for attenuating insertion pain during colonoscopy without sedation, but its efficacy is limited in more painful endoscopy.

Helicobacter pylori induces mono-(adenosine 5'-diphosphate)-ribosylation in human gastric adenocarcinoma.

Mono-(adenosine 5'-diphosphate) (ADP)-ribosylation, which transfers an ADP-ribose from nicotinamide adenine dinucleotide (NAD) to an acceptor protein, is an important post-translational modification of cellular proteins. Several bacterial toxins are known to possess the mono-ADP-ribosyltransferase activity to catalyze this reaction as a possible pathogenic factor. Therefore, the aim of this study was to examine whether H. pylori may also induce mono-ADP-ribosylation in a human gastric mucosal protein in association with gastric cancer development. Tumorous and adjacent non-tumorous mucosal tissue specimens were obtained from the surgically removed stomachs of 5 patients with gastric adenocarcinoma, and then were homogenized into cytosolic and membranous fractions. Each homogenate or an H. pylori extract was assayed for mono-ADP-ribosylation with [adenylate-(32)P]-NAD and 3-aminobenzamide, a potent inhibitor of poly-ADP-ribosylation. The radiolabeled proteins were separated by sodium dodecylsulfate-polyacrylamide gel electrophoresis followed by radio-image analysis. In the extracts from H. pylori, a strain-dependent, endogenous radiolabeling of 70-kDa protein was detected. An assay of the membranous fractions from 5 gastric adenocarcinomas with the extract of OMH4, a clinical H. pylori isolate, revealed notable radiolabelings of 55- and 45-kDa proteins, which were not found without the OMH4 extract. In contrast, the radiolabelings were minimal in the membranous fractions from respective non-tumorous mucosae, and they were not detected in any of the examined cytosolic fractions. All three radiolabelings of 70-, 55-, and 45-kDa proteins were dependent on NAD, but not on ADP-ribose. Snake venom phosphodiesterase digestion of the 3 radiolabeled proteins released only AMP. We thus found that H. pylori had an enzymatic mono-ADP-ribosyltransferase activity which enabled it to modify the 55- and 45-kDa membranous proteins of human gastric adenocarcinoma, as well as the 70-kDa protein of H. pylori itself. The possible roles underlying our observations on carcinogenesis or development of human gastric carcinoma are yet to be elucidated.

Objective assessment of the antispasmodic effect of shakuyaku-kanzo-to (TJ-68), a Chinese herbal medicine, on the colonic wall by direct spraying during colonoscopy.

AIM: To objectively evaluate the effect of TJ-68 on colonic spasms during colonoscopy. METHODS: One hundred and one patients subjected to screening colonoscopy were randomly assigned to two groups: TJ-68 in 51 subjects and saline as the control in 50. The endoscope was inserted into the sigmoid colon, then a spastic region was identified and the tip of the colonoscope was positioned at a distance of about 10 mm from the spastic region. The endoscopic view was recorded before and after direct spraying of the TJ-68 solution or warm saline. The intraluminal area of the spastic region was serially measured using a computer image analyzer and expressed as pixel counts. The area under the curve (AUC) was calculated from the pixel curve. Statistical significance was assessed by Wilcoxon's test and Mann-Whitney U test. RESULTS: The mean AUC of the spastic region before and after TJ-68 spraying was 29,128 and 121,943 pixels, respectively, while with saline, it was 31,635 pixels and 48,617 pixels, respectively. Thus, the AUC significantly increased after TJ-68 spraying compared with the spraying of saline (P<0.001). CONCLUSION: Direct spraying of TJ-68 on the colonic mucosa suppressed colonic spasm and it may be useful during colonoscopy when anticholinergic agents are contraindicated.