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Dive into the research topics where Naotaka Fujita is active.

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Featured researches published by Naotaka Fujita.


Journal of Hepato-biliary-pancreatic Sciences | 2015

Clinical practice guidelines for the management of biliary tract cancers 2015: the 2nd English edition

Masaru Miyazaki; Hideyuki Yoshitomi; Shuichi Miyakawa; Katsuhiko Uesaka; Michiaki Unno; Itaru Endo; Takehiro Ota; Masayuki Ohtsuka; Hisafumi Kinoshita; Kazuaki Shimada; Hiroaki Shimizu; Masami Tabata; Kazuo Chijiiwa; Masato Nagino; Satoshi Hirano; Toshifumi Wakai; Keita Wada; Hiroyuki Iasayama; Takuji Okusaka; Toshio Tsuyuguchi; Naotaka Fujita; Junji Furuse; Kenji Yamao; Koji Murakami; Hideya Yamazaki; Hiroshi Kijima; Yasuni Nakanuma; Masahiro Yoshida; Tsukasa Takayashiki; Tadahiro Takada

The Japanese Society of Hepato‐Biliary‐Pancreatic Surgery launched the clinical practice guidelines for the management of biliary tract and ampullary carcinomas in 2008. Novel treatment modalities and handling of clinical issues have been proposed after the publication. New approaches for editing clinical guidelines, such as the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system, also have been introduced for better and clearer grading of recommendations.


Digestive Endoscopy | 2013

Wire-guided biliary cannulation technique does not reduce the risk of post-ERCP pancreatitis: Multicenter randomized controlled trial

Go Kobayashi; Naotaka Fujita; Kazuomi Imaizumi; Atsushi Irisawa; Masaki Suzuki; Akihiko Murakami; Shuhei Oana; Naohiko Makino; Tomoya Komatsuda; Kazuo Yoneyama

To evaluate the effect of wire‐guided biliary cannulation (WGC) on the prevention of post‐endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP).


Journal of Gastroenterology | 2007

Histological study of gallbladder and bile duct epithelia in patients with anomalous arrangement of the pancreaticobiliary ductal system: comparison between those with and without a dilated common bile duct

Yutaka Noda; Naotaka Fujita; Go Kobayashi; Kei Ito; Jun Horaguchi; Osamu Takasawa; Kazuhiko Ishida; Shigeharu Senoo; Makoto Yonechi; Takashi Suzuki; Dai Hirasawa; Toshiki Sugawara; Masao Kobari; Takashi Sawai; Miwa Uzuki; Mika Watanabe

BackgroundWe histologically evaluated the epithelia of the gallbladder (GB) and bile duct (BD) in patients with anomalous arrangement of the pancreaticobiliary ductal system (AAPB), with regard to the shape of the common BD (CBD).MethodsThe GB and BD were studied histologically using surgical materials from 44 patients with AAPB: 27 with a dilated CBD (D-type) and 17 with a nondilated CBD (N-type).ResultsGB cancer and BD cancer were found in 11.1% and 3.7% of D-type and 17.6% and 0% of N-type respectively. Hyperplastic epithelium and atypical epithelium of the GB were frequently seen in both D-type (46%, 46%) and N-type (82%, 70%), while such epithelia of the BD were only seen in D-type (10%, 35%). The Ki67 labeling index of the nonneoplastic epithelium of the GB was high in both D-type (13.0%) and N-type (9.7%), though that of the BD was high in D-type (12.5%) but low in N-type (1.8%). The prevalences of pyloric gland metaplasia, intestinal metaplasia, and p53 protein overexpression of the nonneoplastic epithelium did not show any significant differences between D-type and N-type.ConclusionsIt is suggested that the BD epithelium of N-type probably has a lower potential for developing malignancy than that of D-type, while the GB epithelia of both D-type and N-type have a high potential for developing malignancy. This might support the selection of simple cholecystectomy as the treatment of choice in AAPB patients of N-type, although further investigation of the BD epithelium is required in a larger number of such patients.


Journal of Gastroenterology | 2014

Pancreatobiliary reflux in individuals with a normal pancreaticobiliary junction: a prospective multicenter study

Jun Horaguchi; Naotaka Fujita; Terumi Kamisawa; Goro Honda; Kazuo Chijiiwa; Hiroyuki Maguchi; Masao Tanaka; Mitsuo Shimada; Yoshinori Igarashi; Kazuo Inui; Keiji Hanada; Takao Itoi; Yoshinori Hamada; Tsugumichi Koshinaga; Hideki Fujii; Naoto Urushihara; Hisami Ando

BackgroundPancreatobiliary reflux (PBR) can occur in individuals without pancreaticobiliary maljunction. The aim of this study was to elucidate the incidence of PBR in individuals with a normal pancreaticobiliary junction and its impact on the biliary tree.MethodsData were prospectively collected from 15 centers on 420 patients with a morphologically normal pancreaticobiliary junction who had undergone bile sampling and measurement of the biliary amylase level. We investigated the incidence and predictive factors for high biliary amylase levels (HBAL), as well as the relationship of HBAL with biliary malignancy.ResultsTwenty-three patients (5.5xa0%) showed HBAL (≥10,000xa0IU/L). Univariate analysis showed that risk factors for the elevation of biliary amylase levels were the existence of a relatively long common channel (≥5xa0mm), acute pancreatitis, and papillitis. Multivariate analysis revealed that only the existence of a relatively long common channel was a significant factor for PBR. Biliary amylase levels in patients with a relatively long common channel were significantly higher than in patients without a long common channel (12,333 vs. 2,070xa0IU/L, Pxa0=xa00.001). The incidence of HBAL (Pxa0<xa00.001), as well as the overall biliary amylase levels (Pxa0=xa00.007) were significantly higher in patients with gallbladder cancer than in those without gallbladder cancer.ConclusionsThe PBR was frequently observed in individuals with a relatively long common channel. Patients showing HBAL with normal pancreaticobiliary junction are at high risk for gallbladder cancer.


Digestive Endoscopy | 2015

Guidelines for sedation in gastroenterological endoscopy

Katsutoshi Obara; Ken Haruma; Atsushi Irisawa; Mitsuru Kaise; Takuji Gotoda; Masanori Sugiyama; Satoshi Tanabe; Akira Horiuchi; Naotaka Fujita; Makoto Ozaki; Masahiro Yoshida; Toshiyuki Matsui; Masao Ichinose; Michio Kaminishi

Recently, the need for sedation in gastrointestinal endoscopy has been increasing. However, the National Health Insurance Drug Price list in Japan does not include any drug specifically used for the sedation. Although benzodiazepines are the main medication, their use in cases of gastrointestinal endoscopy has not been approved. This has led the Japan Gastrointestinal Endoscopy Society to develop the first set of guidelines for sedation in gastrointestinal endoscopy on the basis of evidence‐based medicine in collaboration with the Japanese Society for Anesthesiologists. The present guidelines comprise 14 statements, five of which were judged to be valid on the highest evidence level and three on the second highest level. The guidelines are not intended to strongly recommend the use of sedation for gastrointestinal endoscopy, but rather to indicate the policy as to the choice of appropriate procedures when such sedation is deemed necessary. In clinical practice, the final decision as to the use of sedation should be made by physicians considering patient willingness and physical condition.


Journal of Gastroenterology | 2017

Evidence-based clinical practice guidelines for cholelithiasis 2016

Susumu Tazuma; Michiaki Unno; Yoshinori Igarashi; Kazuo Inui; Kazuhisa Uchiyama; Masahiro Kai; Toshio Tsuyuguchi; Hiroyuki Maguchi; Toshiyuki Mori; Koji Yamaguchi; Shomei Ryozawa; Yuji Nimura; Naotaka Fujita; Keiichi Kubota; Junichi Shoda; Masami Tabata; Tetsuya Mine; Kentaro Sugano; Mamoru Watanabe; Tooru Shimosegawa

Cholelithiasis is one of the commonest diseases in gastroenterology. Remarkable improvements in therapeutic modalities for cholelithiasis and its complications are evident. The Japanese Society of Gastroenterology has revised the evidence-based clinical practice guidelines for cholelithiasis. Forty-three clinical questions, for four categories—epidemiology and pathogenesis, diagnosis, treatments, and prognosis and complications—were selected, and a literature search was performed for the clinical questions with use of the MEDLINE, Cochrane, and Igaku Chuo Zasshi databases for the period between 1983 and June 2012. The guidelines were developed with use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. This article preferentially describes the clinical management of cholelithiasis and its complications. Following description of the diagnosis performed stepwise through imaging modalities, treatments of cholecystolithiasis, choledocholithiasis, and hepatolithiasis are introduced along with a flowchart. Since there have been remarkable improvements in endoscopic treatments and surgical techniques, the guidelines ensure flexibility in choices according to the actual clinical environment. The revised clinical practice guidelines are appropriate for use by clinicians in their daily practice.


Digestive Endoscopy | 2012

Prospective randomized controlled study comparing cell block method and conventional smear method for pancreatic juice cytology.

Yutaka Noda; Naotaka Fujita; Go Kobayashi; Kei Ito; Jun Horaguchi; Shinsuke Koshita; Yoshihide Kanno; Yasunobu Yamashita; Yuhei Kato; Takahisa Ogawa; Takashi Tsuchiya; Masaya Oikawa; Takashi Sawai; Hiroyuki Kanno; Akira Kurose

Aim:u2002 To elucidate the diagnostic efficacy of the cell block (CB) method by comparing it with that of conventional smear cytology for pancreatic juice obtained by endoscopic retrograde cholangiopancreatography (ERCP) in a randomized controlled trial fashion.


Pancreas | 2015

Japanese Clinical Guidelines for Endoscopic Treatment of Pancreatolithiasis.

Kazuo Inui; Yoshinori Igarashi; Atsushi Irisawa; Hirotaka Ohara; Susumu Tazuma; Yoshiki Hirooka; Naotaka Fujita; Hiroyuki Miyakawa; Naohiro Sata; Tooru Shimosegawa; Masao Tanaka; Keiko Shiratori; Masanori Sugiyama; Yoshifumi Takeyama

Objectives In addition to surgery, procedures for patients with pancreatolithiasis are developing; therefore, establishing practical guidelines for the management of pancreatolithiasis is required. Methods Three committees (the professional committee for asking clinical questions (CQs) and statements by Japanese endoscopists, the expert panel committee for rating statements by the modified Delphi method, and the evaluating committee by moderators) were organized. Eight endoscopists and a surgeon for pancreatolithiasis made the CQs and statements from a total of 694 reports of published literature by PubMed search (from 1983 to 2012). The expert panelists individually rated these clinical statements using a modified Delphi approach, in which a clinical statement receiving a median score greater than 7 on a 9-point scale from the panel was regarded as valid. Results The professional committee made 3, 7, and 10 CQs and statements for the concept and pathogenesis, diagnosis, and treatment, respectively. The expert panelists regarded them as valid after a 2-round modified Delphi approach. Conclusions After evaluation by the moderators, the Japanese clinical guidelines for pancreatolithiasis were established. Further discussions and studies for international guidelines are needed.


Internal Medicine | 2014

Intracholecystic papillary-tubular neoplasm of the gallbladder presenting with jaundice.

Shinichi Hashimoto; Jun Horaguchi; Naotaka Fujita; Yutaka Noda; Go Kobayashi; Kei Ito; Shinsuke Koshida; Yoshihide Kanno; Takahisa Ogawa; Kaori Masu


Acta Gastro-Enterologica Belgica | 1989

MALIGNANT TRANSFORMATION OF HYPERPLASTIC POLYP OF THE STOMACH

Akimichi Chonan; Fukuji Mochizuki; Takashi Ikeda; Tokiaki Toyohara; Naotaka Fujita; Shigeki Lee; Masahiro Nagano; Taihei Murakami; Akira Yano; Go Kobayashi; Masao Ando; Kaoru Shimosegawa; Tadakazu Shimoda

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Go Kobayashi

Jikei University School of Medicine

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Jun Horaguchi

Iwate Medical University

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Atsushi Irisawa

Fukushima Medical University

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Kazuo Inui

Fujita Health University

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Kei Ito

Iwate Medical University

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Yutaka Noda

Fujita Health University

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Fukuji Mochizuki

Jikei University School of Medicine

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