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Dive into the research topics where Tsuyoshi Hayakawa is active.

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Featured researches published by Tsuyoshi Hayakawa.


Digestion | 2003

Increased expression of cytokines and adhesion molecules in rat chronic esophagitis.

Masaki Hamaguchi; Yasuhiro Fujiwara; Takashi Takashima; Tsuyoshi Hayakawa; Eiji Sasaki; Masatsugu Shiba; Toshio Watanabe; Kazunari Tominaga; Nobuhide Oshitani; Takayuki Matsumoto; Kazuhide Higuchi; Tetsuo Arakawa

Background/Aims: Cytokines and adhesion molecules regulate many inflammatory processes in several gastrointestinal diseases. The dynamics of cytokines and adhesion molecules in reflux esophagitis are unknown in detail. We examined the expression and dynamics of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), MIP-2, GRO/cytokine-induced neutrophil chemoattractant-2α (CINC-2α), intercellular adhesion molecule-1 (ICAM-1), leukocyte function-associated antigen 1 (LFA-1; CD11a/CD18), and Mac-1 (CD11b/CD18) in rat chronic reflux esophagitis. Methods: Chronic acid reflux esophagitis was induced in Wistar rats by ligating the transitional region between the forestomach and the glandular portion and wrapping the duodenum near the pylorus with a small piece of an 18-Fr Nélaton catheter. Rats were killed 3 or 21 days after operation. The levels of mRNA expression of cytokines and ICAM-1 were determined by real-time quantitative RT-PCR. Localization of adhesion molecules and cytokines was investigated by immunohistochemical staining, and numbers of LFA-1- or Mac-1-positive cells were quantified. Results: IL-1β, TNF-α, MCP-1, MIP-1α, MIP-2, CINC-2α, and ICAM-1 mRNA expression was significantly increased in esophageal lesions compared with normal esophagus. There were few these cytokines- or adhesion molecule-positive cells in normal esophagus. In regions of esophagitis, numerous inflammatory leukocytes in lamina propria and the submucosal layer exhibited positive reactions for these cytokines and endothelial cells were intensely stained for ICAM-1. Numbers of LFA-1- and Mac-1-positive cells were significantly increased in rat chronic esophagitis. Treatment with rabeprazole almost completely inhibited development of chronic acid reflux esophagitis and significantly decreased expression of cytokines and ICAM-1 mRNA in esophageal tissue compared with control. Conclusion: Cytokines and adhesion molecules play important roles in the pathogenesis of chronic reflux esophagitis in this rat model.


Digestion | 2010

Sleep Dysfunction in Japanese Patients with Gastroesophageal Reflux Disease: Prevalence, Risk Factors, and Efficacy of Rabeprazole

Yasuhiro Fujiwara; Yukie Kohata; Makiko Kaji; Hiroko Nebiki; Tomoaki Yamasaki; Eiji Sasaki; Tsuyoshi Hayakawa; Hirohisa Machida; Tetsuya Tanigawa; Kenji Watanabe; Toshio Watanabe; Kazunari Tominaga; Tetsuo Arakawa

Background and Aim: Several studies performed in Western countries demonstrate the association between sleep dysfunction and gastroesophageal reflux disease (GERD), especially when nighttime heartburn is present. The purpose of this study was to examine the prevalence and risk factors of sleep dysfunction, and the effect of rabeprazole on reflux symptoms and sleep dysfunction in Japanese GERD patients. Methods: A total of 134 GERD patients, including 82 patients with non-erosive reflux disease (NERD), were enrolled. Patients received rabeprazole 10 mg daily for 8 weeks. Patients were asked to complete both a frequency scale for symptoms of GERD (FSSG) questionnaire and a Pittsburgh Sleep Quality Index (PSQI) questionnaire at baseline and 8 weeks after treatment. Results: Sleep dysfunction defined as a PSQI score >5.5 was found in 70 (52.2%) of the GERD patients. NERD was significantly associated with sleep dysfunction compared to erosive reflux disease (OR 2.18, 95% CI 1.05–4.53). However, other factors, including nighttime heartburn, were not associated with sleep dysfunction. Rabeprazole treatment significantly decreased both the FSSG and the PSQI score. Conclusion: The prevalence of sleep dysfunction was high among GERD patients. NERD was identified as a risk factor for sleep dysfunction. Use of a proton-pump inhibitor led to an effective decrease in sleep dysfunction. These results suggest a different pathogenesis of sleep dysfunction in Japanese GERD patients compared to GERD patients in Western countries. However, acid plays an important role in sleep dysfunction in all patients with GERD.


Gut | 2006

Roles of cyclooxygenase 2 and microsomal prostaglandin E synthase 1 in rat acid reflux oesophagitis

Tsuyoshi Hayakawa; Yasuhiro Fujiwara; Masaki Hamaguchi; Takashi Sugawa; Masatsugu Okuyama; Eiji Sasaki; Toshio Watanabe; Kazunari Tominaga; Nobuhide Oshitani; Kazahide Higuchi; Tetsuo Arakawa

Background: Although prostaglandin E2 (PGE2), cyclooxygenase 2 (COX-2), and microsomal prostaglandin E synthase 1 (mPGES-1) are known to play a role in various inflammatory events, their roles in the pathogenesis of gastro-oesophageal reflux disease are not known. Aims: We examined the dynamics of COX-1, COX-2, mPGES-1, mPGES-2, cytosolic PGES (cPGES), and PGE2 synthetic activity in rat acid reflux oesophagitis and the effects of COX-2 inhibitors on the severity of oesophagitis. Methods: Acid reflux oesophagitis was induced by ligating the transitional region between the forestomach and the glandular portion and wrapping the duodenum near the pylorus. Rats were killed on day 3 (acute phase) or day 21 (chronic phase) after induction of oesophagitis. Results: Expression of COX-2 and mPGES-1 was markedly increased in oesophagitis while modest changes in COX-1, cPGES, and mPGES-2 expression were observed. COX-2 and mPGES-1 were colocalised in epithelial cells of the basal layer, as well as inflammatory and mesenchymal cells in the lamina propria and submucosa. COX-2 inhibitors significantly reduced the severity of chronic oesophagitis but did not affect acute oesophageal lesions. COX-2 inhibitors significantly inhibited the increase in PGE2 synthesis in oesophageal lesions on both days 3 and 21. Epithelial proliferation was significantly increased in the basal layer on day 21. Inflammatory cells and epithelial cells of the basal layer exhibited reactions for EP4 in oesophagitis. Conclusion: PGE2 derived from COX-2 and mPGES-1 plays a significant role in the pathogenesis of chronic acid reflux oesophagitis, and possibly in basal hyperplasia and persistent inflammatory cell infiltration.


Digestive Diseases and Sciences | 2003

Esophagogastric varices due to arterioportal shunt in a serous cystadenoma of the pancreas in von Hippel-Lindau disease.

Masatsugu Okuyama; Yasuhiro Fujiwara; Tsuyoshi Hayakawa; Masatsugu Shiba; Toshio Watanabe; Kazunari Tominaga; Akihiro Tamori; Nobuhide Oshitani; Kazuhide Higuchi; Takayuki Matsumoto; Kenji Nakamura; Kenichi Wakasa; Kazuhiro Hirohashi; Shingo Ashida; Taro Shuin; Tetsuo Arakawa

Von Hippel-Lindau (VHL) disease is an autosomal dominant inherited disorder characterized by extensively vascularized tumors and cysts in specific organs. Angiogenesis is a striking future of VHL disease with its characteristic cysts and well-vascularized tumors. The hypervascular nature of VHL lesions has been linked to the overproduciton of vascular endothelial growth factor (VEGF) through increased expression of hypoxia inducible factor-1alpha (HIF-1alpha). Here we describe a rare case of VHL disease with esophageal and gastric varices due to arterioportal shunt in a serous cystadenoma of the pancreas, which, upon immunohistochemical examination, exhibited HIF-1alpha and VEGF expression. Rupture of esophageal varices was successfully treated with endoscopic injection sclerotherapy.


Digestive Endoscopy | 2013

Possible antistenotic effect of tranilast in a patient with small bowel tuberculosis to prevent intestinal obstruction due to stenosis progression by antituberculous chemotherapy

Nobuhide Oshitani; Shogo Takeda; Hiroko Matsumoto; Hiroaki Minamino; Tsuyoshi Hayakawa; Kazuki Aomatsu

Small intestinal tuberculosis is a rare disorder of the small intestine. We report the development of deep small bowel tuberculosis in a rheumatoid arthritis patient who was taking methotrexate. The diagnosis of small bowel tuberculosis was ascertained by typical endoscopic findings and production of interferon gamma in the peripheral blood. The patient was successfully treated with antituberculous chemotherapy combined with an antifibrotic agent, tranilast, to suppress the progression of intestinal stenosis toward symptomatic stricture.


United European gastroenterology journal | 2018

Colorectal polyps located across a fold are difficult to resect completely using endoscopic mucosal resection: A propensity score analysis

Hiroaki Minamino; Yasuaki Nagami; Masatsugu Shiba; Kappei Hayashi; Taishi Sakai; Masaki Ominami; Shusei Fukunaga; Tsuyoshi Hayakawa; Kazuki Aomatsu; Satoshi Sugimori; Tetsuya Tanigawa; Hirokazu Yamagami; Toshio Watanabe; Yasuhiro Fujiwara

Background Incomplete polyp resection during colorectal endoscopic mucosal resection (EMR) might contribute to the development of interval cancer. Objective This retrospective study aimed to determine the incidence of incomplete polyp resection during EMR of colorectal polyps located across a fold compared with that of colorectal polyps located between folds. Methods In total, 262 patients with 262 lesions that were ≥10 mm in diameter and treated with conventional EMR were enrolled. The main outcome was the incidence of incomplete polyp resections. Propensity score matching and inverse probability of treatment weighting (IPTW) were performed to reduce the effects of selection bias. Results Fifty-seven lesions (21.8%) were incompletely resected. After propensity score matching, the lesions located across a fold were at higher risk of incomplete resection than those between folds (26/68, 38.2% vs 7/68, 10.3%; odds ratio (OR): 3.71; 95% confidence interval (CI): 1.61–8.56; p < 0.01). These findings persisted after adjusting for the differences at baseline using the IPTW method (OR: 3.63; 95% CI: 1.72–7.63; p = 0.001). Conclusions There is an increased risk of an incomplete polyp resection for a colorectal polyp that is located across a fold compared with that for a polyp that is located between folds.


Gastroenterology | 2003

Lansoprazole inhibits the development of dextran sodium sulfate-induced colitis in rats

Kazuhide Higuchi; Toshio Watanabe; Atsushi Noguchi; Koichi Taira; Tsuyoshi Hayakawa; Reiko Suto; Harunori Fujita; Soichiro Kayo; Takashi Takashima; Masaki Hamaguchi; Tetsuya Tanigawa; Eiji Sasaki; Kazunari Tominaga; Yasuhiro Fujiwara; Tetsuo Arakawa

was not preventing the activated T cells from proliferating as the numbers were not reduced in the ASM981relative to vehicle-treated mice Conclusions:ASM981 is highly effective in a dlerapeutic setting. ASM981 has strong effects on some of the downstream systemic inthmmatory reactions in this model. The data from th~s severe chronic model of IBD together with the already impressive findings in chronic inflammatory skin disorders lead as to expect ASM981 to be effective in IBD in man


Internal Medicine | 2012

A multicenter study on the prevalence of eosinophilic esophagitis and PPI-responsive esophageal eosinophilic infiltration.

Yasuhiro Fujiwara; Takashi Sugawa; Fumio Tanaka; Hiroshi Tatsuwaki; Masatsugu Okuyama; Tsuyoshi Hayakawa; Kazuki Yamamori; Rikimon Wada; Kenjiro Ohtani; Hironori Uno; Tetsuya Tanigawa; Yoshihisa Watanabe; Kazunari Tominaga; Toshio Watanabe; Osamu Takaishi; Yoshihiko Saeki; Hiroko Nebiki; Nobuhide Oshitani; Hiroshi Sato; Tetsuo Arakawa


American Journal of Physiology-gastrointestinal and Liver Physiology | 2006

Roles of epidermal growth factor and Na/H exchanger-1 in esophageal epithelial defense against acid-induced injury

Yasuhiro Fujiwara; Kazuhide Higuchi; Takashi Takashima; Masaki Hamaguchi; Tsuyoshi Hayakawa; Kazunari Tominaga; Toshio Watanabe; Nobuhide Oshitani; Yutaka Shimada; Tetsuo Arakawa


Digestion | 2010

JGA Keynote Program. The 3rd International Gastrointestinal Consensus Symposium (IGICS)

Alexandra Gutierrez; Tetsuo Arakawa; Yasuhiro Miyake; Tatsuya Toyokawa; Kazuyuki Matsumoto; Masahiro Takahara; Takayuki Imada; Satoru Yagi; Hirokazu Miyatake; Morihito Nakatsu; Masaharu Ando; Mamoru Hirohata; Hisae Yasuhara; Holger Seidl; Felix Gundling; Christian Pehl; Susan Kissler; Wolfgang Schepp; Thomas Schmidt; Yasuhiro Fujiwara; Yukie Kohata; Makiko Kaji; Hiroko Nebiki; Tomoaki Yamasaki; Eiji Sasaki; Tsuyoshi Hayakawa; Hirohisa Machida; Tetsuya Tanigawa; Kenji Watanabe; Toshio Watanabe

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