Publications by authors named "Ohkusa T"

By sequestering activator calcium, the sarcoplasmic reticulum (SR) plays the central role in the excitation-contraction (E-C) cycle of cardiac muscle. Hence, functional changes in the SR in diseased myocardium might critically determine its mechanical characteristics. Previously, we demonstrated that both Ca2+ release and uptake were increased in SR isolated from hearts showing compensatory left ventricular (LV) hypertrophy taken from pressure-overloaded rats.

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To study the effects of percutaneous ethanol injection therapy on livers, we investigated necrotic changes after ethanol injection and fibrotic changes during the repair process in cirrhotic livers in comparison with normal livers. Male rats were treated with oral doses of 3'-methyl-4-dimethylaminoazobenzene and thioacetamide to produce liver cirrhosis. Both control animals and cirrhotic animals were injected with 0.

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Little is known about any alterations in sarcoplasmic reticulum (SR) gene expression associated with cardiac diseases of varying degrees of severity. We assessed, using the reverse transcription-polymerase chain reaction (RT-PCR) technique, SR Ca2+ transport protein gene expression in small tissue samples from failing hearts in patients undergoing cardiac surgery. Total RNA was extracted from 30- to 50-mg samples from the hearts of 13 patients with coronary artery disease, congenital heart disease, or valvular heart disease.

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Cardiac sarcoplasmic reticulum (SR) sequesters Ca2+ and plays a crucial role in the regulation of intracellular Ca2+. Its functional properties are central to the excitation-contraction (E-C) cycle of cardiac muscle. In this study, we examined the hypothesis that alterations in SR function occur during the development of hypertrophy of the left ventricle (LV) induced in rats by pressure overload secondary to abdominal aortic coarctation.

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Background: Aortic input impedance, which represents LV afterload, is considered to be a major determinant for the development of pressure-overload left ventricular (LV) hypertrophy.

Methods And Results: To test whether the sustained change in aortic input impedance might affect the mode of development of LV hypertrophy, coarctation of either the ascending aorta (G1, n = 13) or suprarenal abdominal aorta (G2, n = 12) was performed over 4 weeks in 6-weeks-old Wistar rats. Although peak LV pressure and total systemic resistance were increased similarly in G1 and G2, time to peak LV pressure was decreased by 24% (P < .

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Background: The mechanisms underlying the frequent development of colorectal carcinomas in patients with ulcerative colitis are still unknown.

Aims: To evaluate whether mucosal necrosis and regeneration act as enhancing or promoting factors in colorectal tumorigenesis, development of multiple colorectal tumours was studied in a murine model of ulcerative colitis with azoxymethane pretreatment.

Methods: Periods of chronic ulcerative colitis in mice were induced by three repeated administrations of 3% dextran sulphate sodium subsequent to a single azoxymethane pretreatment, to give conditions similar to the clinically observed active and remission phases.

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To investigate the relation of immunoglobulin-containing cells in the colonic mucosa to mucosal inflammation, we immunohistochemically examined the localization of immunoglobulin-containing mononuclear cells in the lamina propria in dextran sulfate sodium induced colitis in mice. Mice were treated repeatedly with 3% dextran sulfate sodium (MW 54,000) solution or distilled water for a total of 170 days (chronic model), or for 85 days (subacute model) or for 10 days (acute model). IgG, IgA, and IgM-containing mononuclear cells were studied by enzyme immunostaining.

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[Adenoacanthoma].

Ryoikibetsu Shokogun Shirizu

September 1996

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Our aim was to determine whether the development of gap junctions in the human gastric mucosa has any relation to gastric ulcer and gastric carcinoma. Freeze-fracture replicas were prepared from the endoscopic biopsy specimens of 20 patients with gastric ulcer and 7 healthy volunteers. Large fractured areas of lateral cell membranes of surface mucous cells were examined randomly under an electron microscope.

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Because endoscopic examinations are a crucial first step in the diagnosis of carcinomas, we have analyzed point mutations of the c-K-ras and p53 genes using biopsied samples. There is no previous report of such an approach, using only biopsied materials. We analyzed point mutations of the c-K-ras and p53 genes using 60 colorectal and 31 gastric tumor biopsy specimens.

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Background: Helicobacter pylori (H pylori) infection has been suggested to be a risk factor for gastric carcinogenesis. However, those previous studies have been concerned with advanced cancer cases. To the authors' knowledge, no detailed investigation on the prevalence of H pylori in early stage gastric cancer tissue has been performed.

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The efficacy and safety of the various sclerosants available for esophageal sclerotherapy have not been adequately investigated. In the present study, we experimentally evaluated the effects on local vascular occlusion and systemic blood coagulation of five sclerosants: 5% ethanolamine oleate, 99.5% ethanol, 2% aethoxysclerol, thrombin, and n-butyl-2-cyanoacrylate.

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We investigated the influence of lactosucrose on the intestinal flora of healthy volunteers. Eight healthy volunteers (male:female = 4:4, age 34 +/- 4 years) received 6 g of lactosucrose daily for 8 weeks. Fecal microflora, bacterial metabolites, pH, and moisture were analyzed before and after the administration of lactosucrose.

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We previously reported that numerous macrophages which phagocytosed dextran sulfate sodium were observed to have accumulated in the mucosal lesions and in the spleen in experimental ulcerative colitis induced in mice with dextran sulfate sodium. In this paper, we investigated the bacterial phagocytic ability of macrophages which were isolated from spleens of mice treated with 3% dextran sulfate sodium for 6 months. In this model, the number of phagocytosed bacteria (Listeria monocytogenes) and the phagocytic index were significantly decreased.

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This study investigated interactions between mucosal lesions and bacterial invasion in ulcerative colitis using the acridine-orange staining method. In all 16 cases of ulcerative colitis, the mucosa was found to be invaded by small rods and cocci. In five of 10 controls, bacteria were seen only adhering to the mucosa and no bacteria were detected in the five remaining cases.

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The development of gap junctions in the human gastric mucosa has been examined to see if there is any relation to gastric ulcer. Freeze fracture replicas were prepared from the endoscopic biopsy specimens of 20 patients with gastric ulcer (15 men and five women, aged 49 (13) years) and seven healthy volunteers (four men and three women, aged 41 (19) years). Large fractured areas of lateral cell membranes of surface mucous cells were observed randomly at a direct magnification of 15,000 using electron microscopy.

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In this study, long term dextran sulphate sodium administration was studied to ascertain whether colorectal carcinoma could be produced in patients with long standing ulcerative colitis. Simultaneously, changes in the intestinal microflora were analysed. Low grade to high grade dysplasia was seen in three of the five hamsters treated with 1% dextran sulphate sodium solution for 100 days, while no dysplasia was detected in the eight animals concomitantly treated with metronidazole, an antianerobic microbial agent, which prevents colonic ulceration.

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Global left ventricular function and ECGs were continuously monitored by radionuclide ambulatory ventricular function monitoring (VEST) and validated against multigated blood pool analysis (MUGA) and left ventriculography in 26 subjects (study 1). Ejection fraction by VEST (Y) showed good correlation with Y = 5.5 +/- 0.

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Helicobacter pylori has been implicated in the pathogenesis of chronic gastritis and peptic ulcer. However, no report to date has been made on the presence of H. pylori in the whitish exudate of peptic ulcers.

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