Tomoharu Yoshida
Yamaguchi University
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Publication
Featured researches published by Tomoharu Yoshida.
Digestive Endoscopy | 2010
Takashi Tajiri; Hiroshi Yoshida; Katsutoshi Obara; Morikazu Onji; Masayoshi Kage; Seigo Kitano; Norihiro Kokudo; Shigehiro Kokubu; Isao Sakaida; Michio Sata; Hisao Tajiri; Kazuhiro Tsukada; Toshiaki Nonami; Makoto Hashizume; Shouzou Hirota; Naoya Murashima; Fuminori Moriyasu; Katsunori Saigenji; Hiroyasu Makuuchi; Kazuhiko Oho; Tomoharu Yoshida; Hiroaki Suzuki; Akitake Hasumi; Kiwamu Okita; Shunji Futagawa; Yasuo Idezuki
General rules for recording endoscopic findings of esophageal varices were initially proposed in 1980 and revised in 1991. These rules have widely been used in Japan and other countries. Recently, portal hypertensive gastropathy has been recognized as a distinct histological and functional entity. Endoscopic ultrasonography can clearly depict vascular structures around the esophageal wall in patients with portal hypertension. Owing to progress in medicine, we have updated and slightly modified the former rules. The revised rules are simpler and more straightforward than the former rules and include newly recognized findings of portal hypertensive gastropathy and a new classification for endoscopic ultrasonographic findings.
Journal of Gastroenterology | 2004
Hiroaki Nohara; Naoko Okayama; Nagamu Inoue; Yuji Koike; Kozue Fujimura; Yutaka Suehiro; Yuichiro Hamanaka; Singo Higaki; Hideo Yanai; Tomoharu Yoshida; Toshifumi Hibi; Kiwamu Okita; Yuji Hinoda
BackgroundMacrophage migration inhibitory factor (MIF) is a proinflammatory cytokine and has been shown to be involved in the development of chronic murine colitis. In the +173 G/C polymorphism of the MIF gene, the presence of C creates the binding motif of activator protein 4. This study explored the association of this polymorphism with ulcerative colitis (UC).MethodsGenotyping was carried out, with a tetra-primer polymerase chain reaction (PCR) method, for 659 DNA specimens from 438 healthy volunteers and 221 patients with UC. Genotype distribution between cases and controls and the association of patients’ genotypes with clinical parameters were statistically evaluated.ResultsNo significant difference in genotype distribution was found between UC patients and healthy controls. However, when the relation of the C/C genotype to clinical parameters in UC patients was evaluated by Fisher’s exact test, it was found that the frequency of the C/C genotype was higher in patients with pancolitis type than in those with other types restricted to the distal or left-sided colon (odds ratio [OR], 10.781; 95% confidence interval [CI], 1.342–86.619; P = 0.0074).ConclusionsThese data suggest that the MIF −173 G/C polymorphism may be related to the extent of disease in UC in a Japanese population.
Gastrointestinal Endoscopy | 1996
Hideo Yanai; Tomoharu Yoshida; Toshiya Harada; Yusuke Matsumoto; Makoto Nishiaki; Toshinori Shigemitsu; Masahiro Tada; Kiwamu Okita; Toyokazu Kawano; Susumu Nagasaki
BACKGROUND Detailed information on the depth of invasion of superficial esophageal cancer is required for endoscopic mucosal resection. As a pretherapeutic diagnostic procedure, endoscopic ultrasonography using conventional 7.5 MHz systems has been ineffective at providing sufficient details. A newly developed, thin ultrasound probe system provides both radial and linear scanning for evaluation of superficial esophageal cancer. METHODS Endoscopic ultrasonography was performed in 16 patients using a switchable probe driven at 20 MHz. Seventeen lesions of superficial esophageal cancer were evaluated for depth of invasion to discriminate mucosal from submucosal penetration. RESULTS The overall accuracy of staging was 64.7%. In all six errors, mucosal cancers were overstaged as submucosal invasion. The diagnostic accuracy was 80% when the muscularis mucosae was visualized. CONCLUSION A 20 MHz linear-radial switchable probe is a useful new method in the staging of superficial esophageal cancer.
Cancer Genetics and Cytogenetics | 2001
Saori Takeo; Hiroshi Arai; Noriyoshi Kusano; Tomohiko Harada; Tomoko Furuya; Shigeto Kawauchi; Atsunori Oga; Takashi Hirano; Tomoharu Yoshida; Kiwamu Okita
To identify amplified oncogenes involved in hepatocellular carcinomas (HCC), we applied a genomic DNA microarray spotted with 57 oncogenes to 20 HCCs. Aberrations in DNA copy number also were analyzed by comparative genomic hybridization (CGH) using an aliquot of DNA samples. In 5 of 20 HCCs, only 6 oncogenes (CCND1, FGF3/FGF4, SAS/CDK4, TERC, MET, and MYC) were amplified, whereas in the remaining 15 tumors no oncogenes were amplified. A comparison of DNA microarray and conventional CGH analyses showed that, although 5 of 6 amplified oncogenes shown by microarray were located in chromosomal regions shown by CGH to have increased DNA copy numbers, not all genes located in such chromosomal regions were affected. One of the amplified oncogenes (SAS/CDK4) was found in a chromosomal region that was undetected by CGH. We, therefore, conclude that amplification of the oncogenes examined in this series is not directly implicated in hepatocellular carcinogenesis.
Journal of Gastroenterology and Hepatology | 2008
Yasuyuki Shirai; Tomoharu Yoshida; Ryu Shiraishi; Takeshi Okamoto; Hiroki Nakamura; Toshiya Harada; Jun Nishikawa; Isao Sakaida
Background and Aim: Computer‐based endoscopic simulators have been developed in recent years, and their usefulness has been reported. However, there is no blinded prospective randomized controlled study on esophagogastroduodenoscopy (EGD) training using virtual reality simulators. The present study aimed to assess the effectiveness of a computer‐based simulator for basic training in EGD.
Journal of Gastroenterology and Hepatology | 1999
Tomoharu Yoshida; Toshiya Harada; Toshinori Shigemitsu; Yoshifumi Takeo; Seiji Miyazaki; Kiwamu Okita
Background: Cyanoacrylate injection is highly effective and is regarded as the treatment of choice in bleeding gastric varices in Europe, but intravenous injection of cyanoacrylate is not allowed in the USA and Japan because it may cause embolisms in other organs. Accordingly, we developed a new endoscopic combined treatment of endoscopic management of gastric varices using a detachable snare (EVLs) and simultaneous endoscopic sclerotherapy and O‐ring ligation (EISL) (i.e. EVLs + EISL), and we prospectively evaluated its efficacy and safety.
Journal of Gastroenterology | 2004
Tomoko Kitoh; Hideo Yanai; Yuki Saitoh; Youhei Nakamura; Yoshitaka Matsubara; Hideaki Kitoh; Tomoharu Yoshida; Kiwamu Okita
BackgroundMatrix metalloproteinase-7 (MMP-7), a proteolytic enzyme, is suspected to play an important role in the progression of various cancers. To clarify the clinical importance of MMP-7, we retrospectively analyzed MMP-7 expression in gastric epithelial tumors.MethodsWe tested 201 lesions (from 172 patients) of surgically or endoscopically resected gastric epithelial tumors (gastric cancer, 158 lesions; gastric adenoma, 32 lesions; hyperplastic polyp, 11 lesions). MMP-7 expression was immunohistochemically examined. Sections with immunostaining signals in more than 30% of tumor cells were judged to show positive expression.ResultsMMP-7 was expressed in 33.3% (67/201) of all lesions. MMP-7-positive tumors were significantly more frequent in diffuse-type adenocarcinomas (62.2%; 28/45) compared with intestinal-type lesions (31.9%; 36/113; P < 0.001). Cancers invading the submucosa or deeper (60.5%; 46/76) were showed positivity significantly more frequently than mucosal cancers (22.0%; 18/82; P < 0.001). MMP-7-positive lesions increased with the progression of gastric epithelial tumors, including adenomas, mucosal cancers, and cancers invading the submucosal layer or deeper (P < 0.001). MMP-7 expression occurred significantly more often in lymphatic invasion-positive cancers (65.1%; 41/63) than in lymphatic invasion-negative cancers (24.2%; 23/95; P < 0.001).ConclusionsThe MMP-7-positive rate increased with the progression of gastric epithelial tumors, such as adenoma, mucosal cancer, and cancer invading the submucosal layer or deeper. MMP-7 was significantly associated with aggressive pathological phenotypes of cancer. The detection of the MMP-7 protein may be useful in pretherapeutic diagnosis.
Journal of Gastroenterology and Hepatology | 1999
Shingo Higaki; Akiko Akazawa; Hiroki Nakamura; Hideo Yanai; Tomoharu Yoshida; Kiwamu Okita
Background: The metaplastic polyp of the colon is a non‐neoplastic lesion that is generally identified as white, flat and having a smooth surface. In general, this polyp is small, is less than 5 mm in diameter but is occasionally larger than 5 mm in diameter, and forms a swelling. The aims of the present study were to clarify the factors that determine the morphology of protruding metaplastic polyps. More specifically, we investigated whether the metaplastic polyp forms as a result of an abnormality in cell proliferation or inflammation of the region.
Journal of Gastroenterology | 2008
Naomi Uemura; Hideto Inokuchi; Hiroshi Serizawa; Toshiharu Chikama; Masao Yamauchi; Tomomi Tsuru; Toru Umezu; Toshiro Urata; Nobuo Yurino; Satoshi Tanabe; Tomoharu Yoshida; Susumu Kawamura; Atsushi Murakami; Munemitsu Yamamoto; Tsutomu Chiba
BackgroundThere is increasing awareness of nonerosive reflux disease (NERD) as a disease requiring treatment in Japan. This randomized, double-blind, placebo-controlled, parallel-group study was conducted to investigate the efficacy and safety of omeprazole 10 mg and 20 mg once daily in Japanese patients with NERD.MethodsPatients with heartburn for at least 2 days a week during the month before entry into the study and no endoscopic signs of a mucosal break (grade M or N according to Hoshihara’s modification of the Los Angeles classification) were randomly assigned to one of three groups (omeprazole 10 mg or 20 mg, or placebo) once daily for 4 weeks.ResultsOverall, 355 patients were enrolled, of whom 284 were randomly assigned to one of the three groups (omeprazole 10 mg, n = 96; omeprazole 20 mg, n = 93; placebo, n = 95). The rate of complete resolution of heartburn in week 4 was significantly higher in patients treated with omeprazole 10 mg [32.3%, 95% confidence interval (CI), 22.9%–41.6%] or 20 mg (25.8%, 95% CI, 16.9%–34.7%) than in the placebo group (12.0%, 95% CI, 5.3%–18.6%). No significant difference between the two omeprazole groups was observed. The rate of complete resolution of heartburn by omeprazole was similar between patients with grade M and those with grade N esophagus. Omeprazole also increased the rate of sufficient relief from heartburn. Omeprazole was well tolerated.ConclusionsOmeprazole 10 mg or 20 mg once daily is effective and well tolerated in patients with NERD regardless of their endoscopic classification.
Journal of Gastroenterology and Hepatology | 2007
Masaaki Satake; Jun Nishikawa; Yuki Fukagawa; Keiko Akashi; Takeshi Okamoto; Tomoharu Yoshida; Atsuyoshi Hirano; Noboru Maetani; Youzou Iida; Isao Sakaida
Background and Aim: A beneficial effect of Helicobacter pylori (H. pylori) eradication in patients with H. pylori‐positive idiopathic thrombocytopenic purpura (ITP) has been reported by several investigators; however, it was not clear whether the recovered platelet count after H. pylori eradication was maintained for a long period.