Hidenori Kurakata

Effectiveness of high‐dose barium enema filling for colonic diverticular bleeding

Aim  Therapeutic barium enema was first reported in 1970. The long‐term recurrence rate of colonic diverticular bleeding after therapeutic barium enema was compared with that of endoscopic haemostasis.

Influence of urease activity in the intestinal tract on the results of 13C-urea breath test

Background and Aim:  A late rise in 13CO2 excretion in the 13C‐urea breath test (UBT) should be found when the substrate passes rapidly through the stomach and makes contact with the colonic bacteria. The aim of this study was to evaluate the influence of intestinal urease activity on the results of the UBT.

High incidence of fermentation in the digestive tract in patients with reflux oesophagitis.

Objectives Because bacteria represent the sole source of gut hydrogen (H2) and methane (CH4), fasting breath H2 and CH4 gases have been used as markers of colonic fermentation. The presence of carbohydrates in the colonic lumen inhibits gastric and pancreatic secretions, and also influences lower oesophageal sphincter function in gastro-oesophageal reflux disease. Materials and methods Studies were performed in 793 consecutive patients undergoing oesophagogastroscopy (270 men and 523 women, aged 19–85 years). A fasting breath sample (20 ml) was collected before endoscopy. At endoscopy, we intubated the stomach without inflation by air, and 20 ml of intragastric gas was collected through the biopsy channel. Next, the tip of the endoscope was inserted into the second portion of the duodenum without inflation by air, and 20 ml of intraduodenal gas was collected. H2 and CH4 concentrations of each sample were measured by gas chromatography. Results Reflux oesophagitis was found in 147 of the 793 patients. The mean values of the H2 and/or CH4 levels of samples taken from the stomach, duodenum and exhaled air were higher in patients with reflux oesophagitis than those without reflux oesophagitis. High H2 and/or CH4 levels were more frequently found in patients with reflux oesophagitis. Conclusions We concluded that the presence of fermentation in the digestive tract was considered to be a risk factor for developing reflux oesophagitis.

Developmentally regulated expression of matrix metalloproteinases during fetal rat colon morphogenesis

To investigate the role of matrix metalloproteinases (MMPs) during gastrointestinal tract development, the expression of gelatinases (MMP‐2 and MMP‐9) was investigated during fetal rat colon morphogenesis. Fetal rat colons were separated into epithelial and mesenchymal fractions without cross contamination using a chelating agent and a dissecting microscope. Gelatinase activity measured using fluorescently labeled gelatin was higher in the mesenchymal than in the epithelial fraction; the developmental profile revealed that, in both fractions, gelatinase activity was enhanced during colon morphogenesis. During colonic gland formation, there was prominent MMP‐2 activity, elevated MMP‐2 mRNA expression, and an increase in the level of the active form of MMP‐2 in the mesenchymal fraction. The mRNA expression of the tissue inhibitor of metalloproteinase 2 corresponded with an elevation in the level of the active form of MMP‐2; the mRNA expression of the cell surface activator of MMP‐2, membrane type matrix metalloproteinase 1, did not increase significantly. MMP‐9 activity was low; only the pro‐form was observed in the epithelial fraction at the end of fetal life. These results suggest that, during colon morphogenesis, MMP activity is under strict spatio‐temporal control, and that the activity of MMP‐2, which is regulated at both the transcriptional and proteolytic activation levels, is very much involved in rat colon morphogenesis.

Endoscopic 13C-Urea Breath Test for Detection of Helicobacter Pylori Infection After Partial Gastrectomy

BACKGROUND/AIMS It is difficult to interpret the results of 13C-urea breath test (UBT) in gastrectomy patients because the test urea may pass through the stomach faster. The aim of this study is to evaluate the efficacy of the modified endoscopic UBT for detection of Helicobacter pylori (H. pylori) infection in the residual stomach. METHODOLOGY An endoscopic UBT was performed in 44 patients who had undergone partial gastrectomy. At endoscopy, 20 mL of water containing 100mg of 13C-urea were sprayed onto the gastric mucosa and an intragastric gas sample was immediately collected through the biopsy channel. Breath samples were collected at 20 min after spraying 13C-urea. RESULTS The intragastric delta13CO2 value in H. pylori-positive patients was significantly higher than those of 20-minute breath samples. The maximum sensitivity and specificity of intragastric samples were 97% and 100% with cutoff point of 5 per thousand, respectively. The sensitivity and specificity of breath samples at 20 min were 71.4% and 66.7% with cutoff point of 0.6 per thousand, respectively. CONCLUSIONS An endoscopic UBT was superior to a standard UBT to detect H. pylori infection after partial gastrectomy.

Ten-Second Endoscopic Breath Test Using a 20-Mg Dose of 13c-Urea to Detect Helicobacter Pylori Infection

BACKGROUND/AIMS Attempts to improve the 13C-urea breath test (UBT) have focused on decreasing the amount of substrate used and reducing the duration of the test. To render the test less expensive and more convenient, we designed a more rapid and less expensive endoscopic UBT with a low dose of 20 mg and a shortened measurement time. METHODOLOGY A total of 178 patients who underwent diagnostic upper endoscopy were enrolled. At endoscopy, 150 mL of intragastric gas sample were collected through a biopsy channel. Following inflation with air, 20 mL of water containing 20 mg of 13C-urea were sprayed onto the gastric mucosa using a spraying instrument. After 10 seconds, a gastric gas sample was collected again. The standard UBT was performed after 3-10 days. RESULTS The delta13CO2 values of intragastric samples in H. pylori-positive patients and H. pylori-negative patients were 76.7 +/- 132.9 per thousand and 1.6 +/- 1.2 per thousand, respectively. With intragastric samples, the maximum sensitivity and specificity of intragastric samples were 83.7% and 100% with cut-off point of 8 per thousand, respectively. CONCLUSIONS Ten-second endoscopic UBT using a 20-mg dose of 13C-urea is a rapid, inexpensive, and accurate method for the detection of H. pylori infection in clinical practice.