Tomoko Itatsu

Eradication of Helicobacter pylori in Hemodialysis Patients

Background. Helicobacter pylori (H. pylori) are a causative agent of digestive disease. Although a proton pump inhibitor combined with amoxicillin-clarithromycin is the accepted drug treatment for H. pylori eradication in Japan, there is no consensus treatment for hemodialysis patients. Study. Seventy-seven hemodialysis patients underwent upper digestive tract endoscopy. Biopsy specimens were taken, and histological findings, culture, and rapid urease tests were performed to confirm the presence of H. pylori. H. pylori-positive patients were then administered at random either a seven-day lansoprazole (60 mg a day)-amoxicillin (750 mg a day)-clarithromycin (400 mg a day) (LAC) regimen or a seven-day lansoprazole (60 mg a day)-clarithromycin (400 mg a day) (LC) regimen. The success of H. pylori eradication was determined from histological findings, culture, and rapid urease tests. Results. In 13 of 77 patients (13.6%), ulcers and/or ulcer scars were seen by endoscopy. Thirty-one patients (40.3%) were positive for H. pylori, and 20 patients among them were randomized to one of two regimens: one is seven-day LAC regimen (eleven patients) and the other is seven-day LC regimen (nine patients). Eradication was successful in nine of the eleven patients (72.7%) receiving the LAC regimen, but in only three of the nine patients (33.3%) who underwent the LC regimen. No serious adverse effects were observed with either regimen, and 95% of the patients reported complete compliance. Conclusion. A seven-day low dose LAC regimen is safe and effective and recommended for treatment of H. pylori infection in hemodialysis patients.

ACTIVATED STELLATE (ITO) CELLS POSSESS VOLTAGE-ACTIVATED CALCIUM CURRENT

We previously reported stellate (Ito) cells possess voltage-activated Ca2+ current. The activation of stellate cells has been indicated to contribute to liver fibrosis and the regulation of hepatic hemodynamics. The aim of this study was to investigate the relationship between voltage-activated Ca2+ current and activation of stellate cells. Voltage-activated Ca2+ current in stellate cells isolated from rats were studied using whole-cell patch clamp technique. L-type voltage-activated Ca2+ current was hardly detected in stellate cells cultured for less than 9 days. Ca2+ current was detected 12.5 and 69% of cells at the 10th and 14th day of culture, respectively. BrdU incorporation indicated cell proliferation was recognized over 50% of cells at the 3rd and 5th day of culture, respectively, then decreased significantly in a time-dependent manner. On the other hand, the expression of alpha-smooth muscle actin indicated cell activation increased from 7th day of culture and collagen type I mRNA appeared remarkably in cells cultured for more than 10 days. In this study, we concluded L-type voltage-activated Ca2+ current was recognized in activated stellate (myofibroblast-like) cells.

A neurotrophic pyrimidine compound, MS-818, enhances EGF-induced restoration of gastric epithelial wounds in vitro

MS-818 is a novel synthetic pyrimidine compound that stimulates nerve regeneration and promotes synthesis of various growth factors and differentiation of astrocytes. Effects of MS-818 on gastric epithelial cells were assessed using a wound repair model with primary cultured gastric epithelial cells from rabbits. A round wound with a constant cell-free area was created and the process of restoration was monitored by measuring wound size every 12 h. Cell proliferation was monitored by sequential staining with BrdU. As previously reported, EGF (10 ng/ml) accelerated wound repair by promoting cell migration and proliferation. Although MS-818 alone had no effects, MS-818 (10-100 microM) enhanced EGF-induced acceleration of gastric epithelial restoration, including cell migration and proliferation. Although the detailed mechanism of action of this agent is still unclear, MS-818 might have favorable effects on in vivo gastric mucosal repair.

Hepatic stellate cell contraction is inhibited by lipo-prostaglandin E1 in vitro

Prostaglandin E1 (PGE1) has been reported to have, experimentally and clinically, a protective effect against liver damage. This effect may result from the relaxation of hepatic stellate cells, whose contraction induces vasoconstriction of hepatic sinusoids. However, prostaglandins are unstable and a new drug delivery system is necessary to administer a sufficient amount of prostaglandin to achieve a protective effect in the liver. The aim of the study is to investigate the effects of lipo‐prostaglandin E1 (lipo‐PGE1) which has a novel drug delivery system on the stellate cell contraction induced by endothelin‐1 in vitro. Lipo‐PGE1 inhibited endothelin‐1‐induced stellate cell contraction in concentrations of 10, 30 and 50 ng/mL. Therefore, lipo‐PGE1 may show a cytoprotective effect in the liver through the relaxation of stellate cells and an increase in the hepatic sinusoidal blood flow.

Multiple early esophageal cancers arising from Barrett's esophagus, and a review of cases of early adenocarcinoma in Barrett's esophagus in Japan

A case of early esophageal adenocarcinoma arising in Barretts esophagus is reported. Many cases of Barretts esophagus, which is considered a premalignant condition, have been reported in Western countries, but few cases have been reported in Japan. The patient, a 53-year-old man with nausea and vomiting, was a drinker (four glasses wine/day for about 30 years), but did not smoke. He had had a hiatal hernia of the esophagus. Since endoscopic biopsies demonstrated an early adenocarcinoma in Barretts esophagus, subtotal esophagectomy was performed. In the resected esophageal material, Barretts esophagus was seen to extend for 12 cm. In addition to the cancer detected preoperatively as a 0-IIc lesion (1.5 cm in diameter), a 0-IIb lesion (1.5 cm in diameter) was also detected in the post-operative survey. Both lesions were well differentiated adenocarcinoma that had invaded only into the lamina propria mucosa. The 23 cases of early adenocarcinoma in Barretts esophagus that have been reported in Japan were reviewed, and it was learned that the present case is the second of multiple early cancer arising in Barretts esophagus so far reported in Japan.

Case Report: Primary Gastric T-cell Lymphoma Accompanied by HTLV-I, HBV and H. pylori Infection

Primary gastrointe stinal lymphomas are the most common forms of extranodal non-Hodgkin’ s lymphoma (NHL), of which almost half are of the gastrointe stinal tract (1, 2). Most primary gastrointe stinal lymphomas are conside red to be of B-cell origin; those of T-cell origin are very rare (3± 8). Only 38 cases of primary gastric T-cell lymphoma have been reported in the lite rature . Recently, T-cell leukemia virus type I (HTLV-I) has received attention as an etiological factor, as approximate ly half of the reported cases are positive for HTLV-1 antibody. Furthermore , the close association of Helicobacter pylori infection with malignant lymphoma also has been recognized. Here we present a case of primary gastric T-cell lymphoma that was positive not only for HTLV-1 antibody but also HBV and H. pylori infection.

The novel histamine H2 receptor antagonist FRG-8813 prevents delay of wound repair induced by hydrogen peroxide in a rabbit gastric epithelial cell system

Abstract The effects of a novel histamine H2 receptor antagonist (FRG‐8813) on the restoration process of gastric epithelial wounds were assessed using an in vitro wound healing model. FRG‐8813 (1, 10 mol/L) was added to a complete confluent monolayer cell sheet after artificial wounding. The restoration process was analysed by a time‐lapse video system and cell migration, proliferation and apoptosis were assessed. Hydrogen peroxide (1, 3 mmol/L) inhibited restoration after wounding by suppressing cell migration and proliferation and induced epithelial cell apoptosis around the wound. The addition of FRG‐8813 abolished the hydrogen peroxide‐induced retardation and prevented apoptosis, although FRG‐8813 itself did not enhance wound healing. FRG‐8813 may act as a radical scavenger as well as having an anti‐secretory action and may have favourable effects on peptic ulcer healing.