Takanori Koyama

Proportion of reflux esophagitis in 6010 Japanese adults: Prospective evaluation by endoscopy

Abstract: Compared with findings in Western countries, the prevalence of reflux esophagitis in Oriental countries is estimated to be low. In this prospective study, we aimed to examine the proportion of reflux esophagitis in Japanese adults, as evaluated by endoscopy. Endoscopists were prospectively directed to grade esophageal mucosal breaks with esophagitis according to the Los Angeles Classification of Esophagitis in all subjects that underwent endoscopic examination. In total, 6010 subjects underwent endoscopic examination for evaluation of esophagitis grading from December 1996 to February 1998. The subjects included 4394 outpatients who were not receiving medication for gastrointestinal disease and 1616 subjects who visited the hospital for routine physical examinations. The overall proportion of esophagitis was 16.3%. Most of the subjects with esophagitis were classified as having grade A or B (proportion of grades A and B, 9.6% and 4.6%, respectively). The age-related proportion of esophagitis and of severe esophagitis (i.e., grades C and D) increased in females aged over 70 and in males aged over 80. Increased body mass index (partly due to decreased height caused by osteoporosis), and/or hiatal herniation, were related to the proportion of esophagitis in females aged over 70. These data indicated that reflux esophagitis is a common disease in Japan. However, severe esophagitis (grades C and D) is not common.

Evaluation of endoscopic variceal ligation in prophylactic therapy for bleeding of oesophageal varices: A prospective, controlled trial compared with endoscopic injection sclerotherapy

Background: To evaluate the efficacy of endoscopic variceal ligation (EVL) in prophylactic therapy for oesophageal varices, we performed a randomized prospective trial to compare the recurrence of oesophageal varices treated by EVL with those treated by endoscopic injection sclerotherapy.

Prevention of recurrent bleeding from gastric ulcer with a nonbleeding visible vessel by endoscopic injection of absolute ethanol : a prospective, controlled trial

We performed a prospective, randomized trial to assess the efficacy of endoscopic injection therapy with absolute ethanol in preventing recurrent bleeding in patients with nonbleeding visible vessels in gastric ulcers. During the period of 1990 to 1993, 62 patients who bled were found to have gastric ulcers with nonbleeding visible vessels; all of them were enrolled for this trial. The 62 patients were randomly divided into two groups, which were comparable at entry. In group I (33 patients), we performed endoscopic injection therapy with absolute ethanol. In group II (29 patients), we sprayed the ulcers with 0.1% epinephrine and thrombin. Endoscopic injection therapy with ethanol was performed at the second endoscopy in the patients in both groups who had recurrent bleeding. Among the 33 patients in group I, 4 patients (12.1%) rebled after the initial ethanol injection therapy, whereas 10 of 29 patients (34.5%) rebled in the control group (p < .05). No patients in group I required surgical intervention, and ultimate hemostasis was achieved in all 33 group I patients (100%), indicating that endoscopic ethanol injection therapy achieves ultimate hemostasis and prevents recurrent bleeding in patients with gastric ulcers and nonbleeding visible vessels.

Endoscopic ultrasonography for demonstrating loss of multiple-layer pattern of the thickened gallbladder wall in the preoperative diagnosis of gallbladder cancer

Abstract The purpose of this study was to elucidate the roles of endoscopic ultrasonography (EUS), conventional US, CT, and MRI in differential diagnosis of gallbladder wall thickening. We scrutinized images for the presence of the multiple-layer patterns of the thickened gallbladder walls during preoperative images (EUS, n = 22; US, n = 23; CT, n = 20; MRI, n = 15) and retrospectively correlated them with surgical results in 25 patients. The pathological diagnoses included 7 gallbladder cancers, 9 cases of chronic cholecystitis, 5 cases of xanthogranulomatous cholecystitis, and 4 cases of adenomyomatosis. Multiple-layer patterns of gallbladder wall were observed in patients with inflammatory and benign diseases by US, EUS, CT, and MRI. This pattern was demonstrated by EUS more efficiently compared with other means of imaging. All subjects with loss of multiple layers were finally diagnosed by use of EUS as having gallbladder cancer at surgery. Loss of multiple-layer patterns of the gallbladder wall demonstrated by EUS was the most specific finding in diagnosing gallbladder cancer.

EFFECT OF POLYDEXTROSE ON ABSORPTION OF TRIGLYCERIDE AND CHOLESTEROL IN MESENTERIC LYMPH-FISTULA RATS

Abstract In most experimental designs, the inhibitory effect of water-soluble dietary fibers on lipid absorption is evaluated by the decrease in plasma lipid concentration or the increase in fecal lipid output. The aim of this study was to evaluate the acute effect of a water-soluble polysaccharide, polydextrose, on lipid transport to the mesenteric lymph using lymph-fistula rats. The mesenteric lymph duct of rats was cannulated, and an infusion tube was introduced into the duodenum. After recovery, a lipid emulsion containing radioactive triolein and cholesteryl oleate was infused into the duodenum for 8 hr. The tested group was infused with the lipid emulsion containing 5% or 10% polydextrose as dietary fiber. Samples from the lymph-fistula were collected, and the luminal contents and mucosa were collected at the end of infusion. Lymph flow in the mesenteric lymph decreased in the polydextrose group after the infusion. The amounts of both triglyceride and cholesterol remaining in the lumen were greater In the polydextrose group, due to decreased transport of lipid into the lymph. These effects were dose dependent in the 5% and 10% polydextrose groups. The results of this study indicate that polydextrose retarded the transport of triolein and cholesterol into the mesenteric lymph.

Human T-cell lymphotropic virus-associated primary gastric lymphoma.

Adult T-cell leukemia/lymphoma (ATLL) was the first human cancer found to be closely associated with the retrovirus human T-cell lymphotropic virus type I (HTLV-I) (1–5), and it shows diverse clinical features (5, 6). According to a report by the Japan Lymphoma Study Group (7), clinical subtypes of ATLL are divided into four groups: lymphoma, acute, chronic, and smoldering. One characteristic clinical feature of ATLL is involvement of many organs (1–9), and gastrointestinal involvement is important for diagnostic criteria in the lymphoma and acute types of ATLL (6, 7). We previously demonstrated in gastric endoscopic examination that the ratio of gastric involvement of ATLL cells was 23 of 76 cases of ATLL (30.3%), and this ratio was related to the survival period of ATLL patients (9). The stomach is the common extranodal organ for non-Hodgkin’s lymphoma, and most primary gastric non-Hodgkin’s lymphomas are of B-cell origin, and primary gastric T-cell lymphoma is not common (10). ATLL is a T-cell origin lymphoma, and this is the first clinical report of collected cases of HTLV-I associated primary gastric lymphoma (primary gastric ATLL), although there have been several reports on gastric involvement of ATLL (9, 11–14). We describe three primary gastric ATLL cases among 114 ATLL patients. In these cases, involvement of ATLL is limited to the stomach and the regional lymph nodes. General Data. Between 1981 and 1997, 114 patients visiting our hospital were diagnosed as having ATLL. Diagnosis of ATLL was made by the following criteria: 1) the presence of anti-HTLV-I antibodies; 2) lymphoid neoplasia proven histologically and/or hematologically: abnormal lymphoid cells with nuclear irregularity of lobulations and cloverleaf forms; 3) T-cell nature of tumor; and 4) monoclonal integration of HTLV-I provirus in chromosomal DNA (15). The classification of clinical subtypes of ATLL is according to the report of the Japan Lymphoma Study Group (7). Clinical subtypes of ATLL are divided into four groups: lymphoma, acute, chronic and smoldering types (lymphoma: 58 cases, acute: 20 cases, chronic: 6 cases, and smoldering: 4 cases). Eighteen of 58 lymphoma-type ATLL patients had gastric involvement of ATLL cells, and 3 of the 58 cases were primary gastric ATLL. Gastric lesions of ATLL were diagnosed when the tumor cells, which had T-cell nature indicated by positive surface marker (16) and HTLV-I genomic integration with either in situ hybridization or polymerase chain reaction (16), were demonstrated in the gastric tissue specimens. Primary lymphoma in the stomach was diagnosed according to the criteria of Dawson et al (17), which include the following features: no palpable adenopathy or mediastinal adenopathy on radiographic examination; a normal peripheral blood smear; disease mainly confined to the stomach at laparotomy or diagnostic imaging; lymphadenopathy being regional or retroperitoneal in location; and a lack of hepatic or splenic involvement. Manuscript received June 5, 1999; revised manuscript received October 5, 2000; accepted December 28, 2000. From the Departments of *Internal Medicine and Gastrointestinal Endoscopy, †Surgery, ‡Radiology and §Pathology, Saga Medical School, Saga, Saga 849-8501, Japan. Address for reprint requests: Dr. Kazuma Fujimoto, Department of Internal Medicine and Gastrointestinal Endoscopy, Saga Medical School, Nabeshima, Saga, Saga 849-8501, Japan. Digestive Diseases and Sciences, Vol. 46, No. 7 (July 2001), pp. 1381–1386

Stimulatory signals from the central nervous system for ornithine decarboxylase activity in the rat duodenal mucosa

The aim of the present study was to summarize the evidence in support of our previous finding that ornithine decarboxylase (ODC) activity in the rat duodenal mucosa is controlled, in part, by the central nervous system. In the first experiment, we demonstrated an effect of truncal vagotomy on ODC activity in the duodenal mucosa of fasted rats. The increase of ODC activity in the duodenum just before the dark period was abolished by truncal vagotomy. In the second experiment, an effect of glycoprivation of the central nervous system induced by 2-deoxy-D-glucose was shown. Infusion of 2-deoxy-D-glucose into the third cerebroventricle activated ODC in the duodenum in a dose-dependent manner. These results indicate that the central nervous system, in addition to local factors, is related to the increase of ODC activity in the rat duodenal mucosa.

Newly synthesized histamine accelerates ornithine decarboxylase activity in rat intestinal mucosa after ischemia-reperfusion

We previously demonstrated that both histamine synthesis (histidine decarboxylase activity) and polyamine synthesis (ornithine decarboxylase activity) increased in the rat intestinal mucosa after ischemia-reperfusion, whereas the relationship between these two factors remains unclear. To elucidate this relationship, we performed the present study. The superior mesenteric artery was occluded for 15 min followed by reperfusion. After ischemia-reperfusion, histidine decarboxylase activity and ornithine decarboxylase activity in the rat jejunal mucosa were measured in a time-dependent manner. Histidine decarboxylase activity increased 1 hr after ischemia-reperfusion, although ornithine decarboxylase activity did not; however, its activity did increase 6 hr after. The increase of ornithine decarboxylase activity was attenuated when the increase of histamine synthesis was suppressed by the inhibition of histidine decarboxylase activity caused by pretreatment withα-fluoromethylhistidine, a suicide inhibitor of histidine decarboxylase. Pretreatment with H1-receptor antagonist attenuated the increase of ornithine decarboxylase activity after ischemia-reperfusion. These results indicate that the newly synthesized histamine, as indicated by an increase of histidine decarboxylase activity, increases ornithine decarboxylase activity after ischemia-reperfusion of the rat intestinal mucosa.

Efficacy of rabeprazole in patients with reflux esophagitis: A single-center, open-label, practice-based, postmarketing surveillance investigation

Abstract Background: The efficacy of rabeprazole sodium 20 mg/d for the treatment of reflux esophagitis has been demonstrated in several studies in Japan. However, studies of rabeprazole sodium 10 mg/d are lacking. Objective: This study was conducted to assess the efficacy and tolerability of rabeprazole 10 mg/d for the treatment of reflux esophagitis. Methods: Patients diagnosed with reflux esophagitis in routine clinical practice were enrolled in this single-center, open-label, practice-based, post-marketing surveillance investigation. Patients were to receive 10 mg of rabeprazole once daily for 8 weeks. The efficacy of rabeprazole was assessed on the basis of symptoms and endoscopic findings in accordance with the modified Los Angeles classification. Tolerability was assessed using subjective symptoms recorded before, during, and after treatment. Results: Of a total of 61 patients enrolled in this study, 47 (77%; 29 men, 18 women; mean age, 63 years) were included in the efficacy and tolerability analyses. Fourteen (23%) patients, including 5 (8.2%) patients who were treated with rabeprazole 20 mg/d, were excluded from the analyses. Endoscopic examinations were performed before and after treatment in 32 of 47 (68.1%) patients; mucosal lesions were healed in 20 of 32 (62.5%) patients after rabeprazole treatment. In patients with mild mucosal lesions prior to treatment, complete remission was achieved in 17 of 24 (70.8%) patients after treatment. Rates of improvement of symptoms were as follows: epigastralgia, 76%; heartburn, 76.7%; dull pain in the esophagus, 86.7%; and belching, 72.2%. Rabeprazole was well tolerated throughout the study; no serious symptomatic adverse events were reported. Although 1 case each of elevated alkaline phosphatase and gamma-glutamyltranspeptidase levels were reported, these changes were mild and improved after continuous treatment with rabeprazole. Conclusion: In this study, rabeprazole 10 mg/d was well tolerated and was shown to have satisfactory efficacy in the healing of esophagitis and the relief of the symptoms of esophagitis.

Subdiaphragmatic vagotomy abolishes increase in ornithine decarboxylase activity of rat duodenal mucosa after ischemia-reperfusion in superior mesenteric artery

SummaryIn order to evaluate the systemic and neural factors on ornithine decarboxylase (ODC) activity of rat intestinal mucosa, ODC activity in duodenal mucosa, where blood flow did not decrease by superior mesenteric artery (SMA) occlusion, was compared to that of jejunal and ileal mucosa, where blood flow decreased to 90% of the initial value after SMA occlusion. Rats were allowed to recover after SMA occlusion before harvesting intestinal mucosa for measuring ODC activity. ODC activity in the jejunum and the ileum increased markedly 6 h after ischemia-reperfusion (I/R) and more than 72 h were required for ODC activity to return to normal. ODC activity in the duodenum did not change until 24 h after I/R, but the activity increased 48 h after I/R, and this increase continued for 2 days. Subdiaphragmatic vagotomy completely abolished the increase in ODC activity in the duodenum, whereas the same procedure had no influence on ODC activity in the jejunum or the ileum. These results indicate that a neural signal from the central nervous system via the efferent vagal nerve following I/R was an important factor in the increase in ODC activity of duodenal mucosa, where blood flow was not influenced by SMA occlusion.