Tomoki Inaba

Risk factors for perforation and delayed bleeding associated with endoscopic submucosal dissection for early gastric neoplasms: Analysis of 1123 lesions

Background and Aim:  Endoscopic submucosal dissection (ESD) is a useful procedure for the treatment of early gastric neoplasms; however, this advanced technique has also resulted in an increase in serious complications such as perforation and delayed bleeding. This study aimed to elucidate the risk factors for these complications.

Randomized open trial for comparison of proton pump inhibitors in triple therapy for Helicobacter pylori infection in relation to CYP2C19 genotype

Abstract Background and aims : Genetic polymorphism of cytochrome P450 (CYP) 2C19 influences the efficacy of Helicobacter pylori eradication therapy with a proton pump inhibitor (PPI) and amoxicillin. However, in triple therapy (PPI plus amoxicillin and clarithromycin), little is known about the impact of CYP2C19 polymorphism, or the use of rabeprazole, which is not well metabolized by CYP2C19. The efficacy of three PPI (omeprazole, lansoprazole, and rabeprazole) in a 1‐week triple regimen were compared in relation to CYP2C19 polymorphism.

Eradication of Helicobacter pylori increases platelet count in patients with idiopathic thrombocytopenic purpura in Japan.

Background  The effect of Helicobacter pylori eradication on the platelet count in patients with thrombocytopenic purpura is controversial. In this multicentre study, we prospectively assessed the effect of H. pylori eradication therapy in idiopathic thrombocytopenic purpura patients.

Interleukin-1β genetic polymorphism influences the effect of cytochrome P 2C19 genotype on the cure rate of 1-week triple therapy for Helicobacter pylori infection

Interleukin-1β genetic polymorphism influences the effect of cytochrome P 2C19 genotype on the cure rate of 1-week triple therapy for Helicobacter pylori infection

Review of the diagnosis and management of gastrointestinal bezoars

The formation of a bezoar is a relatively infrequent disorder that affects the gastrointestinal system. Bezoars are mainly classified into four types depending on the material constituting the indigestible mass of the bezoar: phytobezoars, trichobezoars, pharmacobezoars, and lactobezoars. Gastric bezoars often cause ulcerative lesions in the stomach and subsequent bleeding, whereas small intestinal bezoars present with small bowel obstruction and ileus. A number of articles have emphasized the usefulness of Coca-Cola(®) administration for the dissolution of phytobezoars. However, persimmon phytobezoars may be resistant to such dissolution treatment because of their harder consistency compared to other types of phytobezoars. Better understanding of the etiology and epidemiology of each type of bezoar will facilitate prompt diagnosis and management. Here we provide an overview of the prevalence, classification, predisposing factors, and manifestations of bezoars. Diagnosis and management strategies are also discussed, reviewing mainly our own case series. Recent progress in basic research regarding persimmon phytobezoars is also briefly reviewed.

Distribution of activated complement, C3b, and its degraded fragments, iC3b/C3dg, in the colonic mucosa of ulcerative colitis (UC)

The third component of complement (C3) is central to both the classical and alternative pathways in complement activation. In this study, involvement of C3 activation in the mucosal injury of UC was investigated. We examined the distribution of activated (C3b) and degraded fragments (iC3b/C3dg) of C3, terminal complement complex (TCC), and complement regulatory proteins in normal and diseased colonic mucosa including UC and other types of colitis using immunohistochemical techniques at the level of light and electron microscopy. While C3b and iC3b/C3dg staining was negligible in the normal mucosa, iC3b/C3dg and, to a lesser extent, C3b were deposited in UC mucosa along the epithelial basement membrane. The deposition was enhanced in relation to the severity of mucosal inflammation (C3b, P < 0.05; iC3b/C3dg, P < 0.01). Epithelial deposition of TCC was not observed in most UC mucosa. Immunoelectron microscopy showed that C3b and iC3b/C3dg were distributed mainly along the epithelial basement membrane and the underlying connective tissue in a granular, studded manner, and weakly present along the basolateral surface of epithelial cells. These C3 fragments were also deposited in inflammatory control mucosa such as ischaemic and infectious colitis. Our findings suggest that deposition of the C3 fragments occurs in inflamed colonic mucosa of diverse etiologies, including UC, but to define a role of the deposition in the development of mucosal injury in UC awaits direct study.

Cytokine-stimulated release of decay-accelerating factor (DAF; CD55) from HT-29 human intestinal epithelial cells

Expression of DAF (CD55) is enhanced on colonic epithelial cells of patients with ulcerative colitis (UC), and stool DAF concentrations are increased in patients with active disease. Cytokines are known to modulate DAF expression in various human cells, and lesions of UC reveal altered profiles of cytokine production. In this study, we evaluate the effects of various cytokines, IL‐1β, IL‐2, IL‐4, IL‐6, IL‐8, IL‐10, and interferon‐gamma (IFN‐γ), on the synthesis and kinetics of DAF protein in HT‐29 human intestinal epithelial cells. Using flow cytometry and an ELISA, we found that HT‐29 cells constitutively express DAF on the cell surface and spontaneously release DAF into the culture supernatant under standard culture conditions. When the culture supernatant was centrifuged at 100 000 g, nearly a half of DAF was precipitated, indicating that one half of the released DAF was present as a membrane‐bound form and the other half as a soluble form. Analysis of the culture supernatant of biotin surface‐labelled HT‐29 cells suggested that the soluble form DAF was derived by secretion from within the cell or by cleavage from the cell surface. Among the cytokines, IL‐4 markedly, and IL‐1β moderately, enhanced the expression and the release of DAF. Actinomycin D, cycloheximide, and brefeldin A inhibited the increase in DAF release induced by IL‐4 and IL‐1β stimulation. These results suggest that DAF is released from intestinal epithelial cells in response to cytokine stimulation and that IL‐4 and IL‐1β are possible cytokines involved in DAF release into the colonic lumen of patients with UC.

Reinfection rate following effective therapy against Helicobacter pylori infection in Japan

Background and Aim: In developed countries, reinfection of Helicobacter pylori (H. pylori) after eradication of the bacterium is unusual, while the reinfection rate in developing countries is variable. In this study, we determined the reinfection rate after successful H. pylori eradication in Japan, a country with a high prevalence of H. pylori infection.

Detection of decay-accelerating factor in stool specimens of patients with colorectal cancer

BACKGROUND & AIMS Colorectal cancers have an increased expression of decay-accelerating factor (DAF). The aim of this study was to determine whether stool specimens of patients with colorectal cancer contain increased amounts of DAF. METHODS DAF was measured using an immunoassay in the stool specimens of 40 persons with colorectal cancer, 18 with colorectal adenomatous polyps, 13 with upper gastrointestinal cancer, and 41 without gastrointestinal disease. RESULTS Stool DAF concentrations in patients with colorectal cancer (0-9.8 ng/g stool; median, 1.6 ng/g) were significantly higher than those in patients with adenoma (0-6.4 ng/g; median, 0 ng/g) (P < 0.05), patients with upper gastrointestinal cancer (0-3.1 ng/g; median, 0 ng/g) (P < 0.05), and subjects without gastrointestinal disease (0-3.4 ng/g; median, 0 ng/g) (P < 0.01). Resection of colorectal cancers caused a marked decrease in stool DAF concentrations. The stool DAF test was positive in a substantial portion of patients with colorectal cancer whose tumors were small ( < 2 cm), at an early TNM stage, or unassociated with fecal occult blood positivity. The sensitivity of the test for colorectal cancer was 55%, and the specificity was 85%. CONCLUSIONS The measurement of stood DAF deserves evaluation as a test for detection of colorectal cancer.

Endoscopic submucosal dissection for cancers of the remnant stomach after distal gastrectomy

BACKGROUND Endoscopic submucosal dissection (ESD) of early gastric cancer is less invasive than surgical resection, and if technically feasible, it may result in less long-term morbidity than does incisional surgery. However, ESD is technically difficult in patients who have had a previous distal gastrectomy. OBJECTIVE Our purpose was to retrospectively assess the results of ESD of early gastric cancer in the remnant stomach. DESIGN Case series. SETTING AND PATIENTS A total of 31 lesions in 30 patients with early remnant gastric cancer were treated with ESD at Okayama University Hospital, Tsuyama Central Hospital, Hiroshima City Hospital, Kagawa Prefectural Central Hospital, and Mitoyo General Hospital from March 2001 to January 2007. INTERVENTION ESD. MAIN OUTCOME MEASUREMENTS En bloc resection rate, complete resection rate, operation time, and complications. RESULTS En bloc resection and complete resection were achieved in 30 (97%) and in 23 (74%) lesions, respectively. The median operation time required for ESD in the remnant stomach was 113 minutes (range 45-450 minutes). Perforation occurred in 4 (13%). The incidence of delayed bleeding requiring blood transfusion was 0%. LIMITATION Short duration of follow-up. CONCLUSIONS ESD is feasible in the remnant stomach but has a relatively high complication rate and should only be performed by experienced endoscopists.