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Featured researches published by Yasuyuki Kihara.


Journal of Gastroenterology | 2008

Asian diagnostic criteria for autoimmune pancreatitis: consensus of the Japan-Korea Symposium on Autoimmune Pancreatitis

Makoto Otsuki; Jae Bock Chung; Kazuichi Okazaki; Myung-Hwan Kim; Terumi Kamisawa; Shigeyuki Kawa; Seung Woo Park; Tooru Shimosegawa; Kyutaek Lee; Tetsuhide Ito; Isao Nishimori; Kenji Notohara; Satoru Naruse; Shigeru B. H. Ko; Yasuyuki Kihara

In 2002, the Japan Pancreas Society (JPS) was the first in the world to propose diagnostic criteria for autoimmune pancreatitis (AIP). Since the concept of AIP has changed with the accumulation of AIP cases, the Research Committee of Intractable Pancreatic Diseases (RCIPD) provided by the Ministry of Health, Labour and Welfare of Japan and the JPS issued revised clinical diagnostic criteria of AIP in 2006. The Asan Medical Center of Korea also proposed diagnostic criteria for AIP in 2006. However, there are subtle but clinically challenging differences between the Japanese and Korean criteria. This inconsistency makes it difficult to compare data in studies from different centers and elucidate the characteristics of AIP. To reach a consensus on AIP, the RCIPD and the Korean Society of Pancreatobiliary Diseases established the following Asian criteria for the diagnosis of AIP: I-1. Imaging studies of pancreatic parenchyma show a diffuse/segmental/focally enlarged gland, occasionally with a mass and/or a hypoattenuation rim. I-2. Imaging studies of pancreaticobiliary ducts show diffuse/segmental/focal pancreatic ductal narrowing, often with stenosis of the bile duct. (Both I-1 and I-2 are required for diagnosis). II. Elevated level of serum IgG or IgG4, and detection of autoantibodies. III. Common lymphoplasmacytic infiltration and fibrosis, with abundant IgG4-positive cell infiltration. AIP should be diagnosed when criterion I and one of the other two criteria are satisfied, or when histology shows the presence of lymphoplasmacytic sclerosing pancreatitis in the resected pancreas. A diagnostic trial of steroid therapy can be applied carefully by expert pancreatologists only in patients fulfilling criterion I alone with negative diagnostic work-up results for pancreatobiliary cancer.


Pancreatology | 2012

The sixth nationwide epidemiological survey of chronic pancreatitis in Japan

Morihisa Hirota; Tooru Shimosegawa; Atsushi Masamune; Kazuhiro Kikuta; Kiyoshi Kume; Shin Hamada; Yasuyuki Kihara; Akihiko Satoh; Kenji Kimura; Ichiro Tsuji; Shinichi Kuriyama

OBJECTIVES A nationwide survey was conducted to clarify the epidemiological features of patients with chronic pancreatitis (CP) in Japan. METHODS Two sequential surveys were conducted. In the first survey, both the prevalence and incidence of CP in Japan in 2007 were estimated by a questionnaire, which was mailed to 3027 randomly chosen Japanese facilities. In the second survey, the second questionnaire was then mailed to 1110 facilities selected by the first survey to clarify the clinicoepidemiological features of the patients. RESULTS The estimated annual prevalence of CP was 36.9 per 100,000; 53.2 in males and 21.2 in females. The estimated annual incidence was 11.9 per 100,000. The prevalence and the incidence of CP gradually increased in Japan as compared to former surveys. The sex ratio (male/female) of definitive and probable CP patients was 4.5, with a mean age of 59.4 years; 59.2 years in males and 60.2 years in females. Alcoholic (69.7%) was most the common and idiopathic (21.0%) was the second most common cause of CP. The proportion of alcoholic CP increased as compared to the 55.5% found in 1994. The clinical features of overall Japanese patients with CP were: abdominal pain (60.6%), malabsorbtion (12.2%), diabetes mellitus (39.7%) and pancreatolithiasis (75.7%). Alcoholic patients were characterized by high morbidity as compared to nonalcoholic patients: abdominal pain (alcoholic 65.0% vs nonalcoholic 53.0%, p < 0.0001), diabetes mellitus (44.8% vs 31.4%, p < 0.0001) and pancreatolithiasis (84.0% vs 60.8%, p < 0.0001). CONCLUSION The prevalence and the incidence of CP, especially alcoholic CP, have been increasing in Japan.


Journal of Gastroenterology | 2001

Pancreatic cancer complicated by disseminated intravascular coagulation associated with production of tissue factor

Chisato Ueda; Yoshihide Hirohata; Yasuyuki Kihara; Hayato Nakamura; Shintaro Abe; Kazuhisa Akahane; Kohji Okamoto; Hideaki Itoh; Makoto Otsuki

A 54-year-old man was diagnosed as having pancreatic cancer and disseminated intravascular coagulation. His plasma tissue factor level on the 11th hospital day was 996 pg/ml (normal range, 120-270 pg/ml). He was treated with gabexate mesilate, antithrombin III, and low-molecular-weight heparin. However, he died of multiple organ failure on the 17th hospital day. The histological finding was poorly differentiated ductal adenocarcinoma of the pancreas, and the production of tissue factor in this lesion was revealed. Tissue factor is a factor that initiates blood coagulation; thus, its expression in pancreatic cancer is one of the causes of coagulation abnormalities in this disease. Although one report has demonstrated immunoreactivity for tissue factor in pancreatic cancer, the patients detailed clinical course was not mentioned in that report. This is the first report to prove that pancreatic cancer produced tissue factor in a patient with disseminated intravascular coagulation.


Gut | 2017

Randomised controlled trial of long-term maintenance corticosteroid therapy in patients with autoimmune pancreatitis

Atsushi Masamune; Isao Nishimori; Kazuhiro Kikuta; Ichiro Tsuji; Nobumasa Mizuno; Tatsuo Iiyama; Atsushi Kanno; Yuichi Tachibana; Tetsuhide Ito; Terumi Kamisawa; Kazushige Uchida; Hideaki Hamano; Hiroaki Yasuda; Junichi Sakagami; Akira Mitoro; Masashi Taguchi; Yasuyuki Kihara; Hiroyuki Sugimoto; Yoshiki Hirooka; Satoshi Yamamoto; Kazuo Inui; Osamu Inatomi; Akira Andoh; Kazuyuki Nakahara; Hiroyuki Miyakawa; Shin Hamada; Shigeyuki Kawa; Kazuichi Okazaki; Tooru Shimosegawa

Objective Corticosteroid has been established as the standard therapy for autoimmune pancreatitis (AIP), but the requirement for maintenance corticosteroid therapy is controversial. We conducted a randomised controlled trial to clarify the efficacy of maintenance corticosteroid therapy in patients with AIP. Design We conducted a multicentre, tertiary setting, randomised controlled trial. After the induction of remission with the initial oral prednisolone (PSL) treatment, maintenance therapy with PSL at 5–7.5 mg/day was continued for 3 years or withdrawn at 26 weeks. The primary endpoint was relapse-free survival over 3 years and the secondary endpoint was serious corticosteroid-related complications. All analyses were performed on an intention-to-treat basis. Results Between April 2009 and March 2012, 49 patients with AIP were randomly assigned to the maintenance therapy group (n=30) or the cessation group (n=19). Baseline characteristics were not different between the two groups. Relapses occurred within 3 years in 11 out of 19 (57.9%) patients assigned to the cessation group, and in 7 of 30 (23.3%) patients in the maintenance therapy group. The relapse rate over 3 years was significantly lower in the maintenance therapy group than that in the cessation group (p=0.011). The relapse-free survival was significantly longer in the maintenance therapy group than that in the cessation group (p=0.007). No serious corticosteroid-related complications requiring discontinuation of PSL were observed. Conclusions Maintenance corticosteroid therapy for 3 years may decrease relapses in patients with AIP compared with those who discontinued the therapy at 26 weeks. Trial registration number UMIN000001818; Results.


Metabolism-clinical and Experimental | 1999

Metabolic abnormalities in the genetically obese and diabetic Otsuka Long-Evans Tokushima fatty rat can be prevented and reversed by α-glucosidase inhibitor

Mitsuyoshi Yamamoto; Dong Mei Jia; Ken-Ichiro Fukumitsu; Issei Imoto; Yasuyuki Kihara; Yosihide Hirohata; Makoto Otsuki

The recently developed Otsuka Long-Evans Tokushima Fatty (OLETF) rat is known to develop insulinopenic diabetes after a prolonged period in a condition resembling non-insulin-dependent diabetes mellitus (NIDDM). We examined the effect of pharmacological intervention with a potent intestinal alpha-glucosidase inhibitor, acarbose, on the metabolic and histopathologic changes in this rat model. The first two groups of rats received an acarbose-rich diet (150 mg/100 g normal chow) from 12 weeks of age (ie, before the onset of diabetes) or from 28 weeks of age (ie, after the onset of diabetes), while a third group received the acarbose-rich diet for the initial 16 weeks only (from 12 to 28 weeks of age). A control group received standard rat chow. Acarbose-fed rats gained less weight or lost weight despite increased food intake when switched to the acarbose-rich diet. Acarbose also reduced visceral adipose depots and fasting triglyceride (TG), glucose, and insulin levels. At the end of the study at 72 weeks, the pancreatic wet weight and insulin content were significantly higher in the treated groups versus control rats. The morphological changes observed in control rats, such as atrophy of the pancreas and reduced number and size of islets, were not present in acarbose-treated rats. Rats fed acarbose from 12 to 28 weeks of age gradually gained weight after switching to standard chow, and hyperinsulinemia, hyperglycemia, and hyperlipidemia appeared (in that order). The pancreatic insulin content in these rats was significantly higher and the visceral adipose depot was significantly smaller than in control rats. Our study demonstrates that acarbose prevented and reversed the metabolic derangement and histopathological changes in genetically diabetic rats. Moreover, treatment with acarbose even for a short period produced a marked delay in the development of insulin insensitivity and frank diabetes.


Pancreas | 2001

Role of TGF-β1, Extracellular Matrix, and Matrix Metalloproteinase in the Healing Process of the Pancreas After Induction of Acute Necrotizing Pancreatitis Using Arginine in Rats

Yasuyuki Kihara; Mitsuo Tashiro; Hayato Nakamura; Taizou Yamaguchi; Hiroyuki Yoshikawa; Makoto Otsuki

Introduction Pancreatic tissues are almost completely restored to normal after an attack of acute pancreatitis, once the cause of the disease is removed. Transforming growth factor (TGF)-&bgr; and extracellular matrix (ECM) are known to play an important role in the process of wound healing in pathologic diseases. Tissue repair is a process regulated by a balance between synthesis and degradation of ECM. Aims To elucidate the role of TGF-&bgr;, ECM, and matrix metalloproteinase (MMP) in the process of regeneration occurring after acute necrotizing pancreatitis. Methodology Acute necrotizing pancreatitis was induced by intraperitoneal injection of 500 mg/100 g body weight of L-arginine in male Wistar rats. Expression of TGF-&bgr;1 and ECM messenger RNA (mRNA) was determined by Northern blot analysis, and that of MMP-1 and MMP-2 mRNA was examined by the reverse transcription polymerase chain reaction (RT-PCR). Immunoreactivity for ECM components, TGF-&bgr;1, and MMP-2 in the pancreas was assessed by using a monoclonal antibody. Results TGF-&bgr;1 mRNA expression reached a peak value on day 2.5, with a decrease on day 3, and reached the control level on day 7. Procollagen types III and IV and fibronectin mRNA reached a peak value on day 2.5, whereas the expression level of procollagen type I mRNA was maximal on day 3, and gradually decreased to control levels by day 7. MMP-2 mRNA was significantly elevated on day 3, and peaked on day 5, whereas MMP-1 mRNA levels did not change throughout the observation period. Immunoreactivity for MMP-2 was observed around disrupted acinar cells and interstitial spaces on day 3, and maximally on day 7. Immunoreactivity for fibronectin was detected around disrupted acinar cells and interstitial spaces. On day 7, it was less than on day 5 around disrupted acinar cells and interstitial spaces, whereas in the regenerated acinar cells, it was undetected. Conclusion Our results show that TGF-&bgr;1 mRNA expression peaked earlier than that of ECM mRNA. Furthermore, increased level of the MMP-2 transcript was followed by disappearance of fibronectin. Our findings suggest that TGF-&bgr;1 plays an important role in ECM production in the early phase of acute pancreatitis, and that MMP-2 is involved in the subsequent healing process.


Journal of Gastroenterology | 1997

Safe and effective treatment of diabetes mellitus associated with chronic liver diseases with an alpha-glucosidase inhibitor, acarbose

Yasuyuki Kihara; Yoshimitsu Ogami; Akinari Tabaru; Hideaki Unoki; Makoto Otsuki

Glucose intolerance and diabetes mellitus are both prevalent in patients with chronic liver diseases. We examined the efficacy and systemic safety of therapy with an alpha-glucosidase inhibitor, acarbose, in diabetes mellitus associated with chronic liver diseases. Twenty patients with chronic hepatitis or liver cirrhosis and overt diabetes mellitus received acarbose (taken orally) for 8 weeks. The initial dosage of acarbose was 50mg three times daily, taken before meals; this was increased to 100mg three times daily after 2 weeks. The mean fasting plasma glucose level was 173.7±18.6mg/dl (mean±SE) at entry, and was significantly decreased to 132.9±7.5mg/dl (P<0.05) after 8 weeks of acarbose treatment. The improved glycemic control was reflected by a significant decrease in glycosylated hemoglobin (HbA1c) from 7.2±0.3% at entry to 6.3±0.2% (P<0.05) after 8 weeks. Serum levels of both aspartate and alanine aminotransferases fluctuated during acarbose treatment, probably due to the natural course of chronic liver diseases, but the mean values had decreased after 8 weeks of treatment. Plasma ammonia levels increased, from 61.3±10.7μg/dl to 71.1±9.6μg/dl after 8 weeks of acarbose treatment but the increase was not significant. Clinically significant elevation of plasma ammonia concentration was seen in 2 cirrhotic patients (121 and 124μg/dl); this was asymptomatic and gradually returned to the normal range despite continuous acarbose treatment in one patient, and was reversed after the withdrawal of acarbose with the concomitant administration of lactulose in the other patient. No other blood tests results, including albumin, cholinesterase, and prothrombin time, or lipid profile and nutritional status, in terms of rapid turnover proteins, prealbumin, retinol binding protein, and transferrin, were altered throughout the study period. These results indicate that diabetes mellitus associated with chronic liver diseases may be safely and effectively treated with acarbose. However, clinicians must be aware of the possibility of hyperammonemia when they prescribe acarbose for patients with diabetes mellitus and advanced liver cirrhosis.


Journal of Gastroenterology | 1998

Defects of cholecystokinin (CCK)-A receptor gene expression and CCK-A receptor-mediated biological functions in Otsuka Long-Evans Tokushima Fatty (OLETF) rats.

Hayato Nakamura; Yasuyuki Kihara; Mitsuo Tashiro; Kenji Kanagawa; Hisashi Shirohara; Mitsuyoshi Yamamoto; Hiroyuki Yoshikawa; Ken-Ichiro Fukumitsu; Yoshihide Hirohata; Makoto Otsuki

Abstract: Recent studies in genetically obese and diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats suggest defects of cholecystokinin (CCK)-A receptor gene expression and CCK-A receptor-mediated biological functions such as pancreatic juice, protein, and gastric acid secretion. The present studies were undertaken to further examine CCK-A receptor gene expression and CCK-A receptor-mediated biological functions in the pancreas, stomach, and brain of OLETF rats. Expression of the CCK-A receptor gene could not be detected in the stomach, pancreas and brain by the reverse-transcription polymerase chain reaction (RT-PCR) method and Southern blotting of the PCR products. Southern blot analysis of genomic DNA from OLETF and control Long-Evans Tokushima Otsuka (LETO) rats with CCK-A receptor fragment as a probe revealed different restriction bands. Expression of the CCK-B receptor gene was observed in the stomach, pancreas, and brain in both OLETF and LETO rats by the RT-PCR method, with expression of the CCK-B receptor gene markedly enhanced in OLETF rats compared with that in LETO rats. Consistent with the defect of CCK-A receptor gene expression, CCK-A receptor-mediated biological functions were not observed in these organs. Perfused exocrine and endocrine pancreas of OLETF rats were insensitive to CCK stimulation but not to carbamylcholine stimulation. Basal gastric acid and pepsinogen secretions in OLETF rats were higher than in LETO rats. OLETF rats showed a significantly higher average daily food intake, gained body weight faster, and were heavier than LETO rats. The present study confirmed that OLETF rats have CCK-A receptor gene anomalies and demonstrated deficient CCK-A receptor-mediated biological function in the pancreas, stomach, and brain.


Pancreas | 2005

Persistent destruction of the basement membrane of the pancreatic duct contributes to progressive acinar atrophy in rats with experimentally-induced pancreatitis

Taizo Yamaguchi; Yasuyuki Kihara; Masashi Taguchi; Yoshikuni Nagashio; Mitsuo Tashiro; Hayato Nakamura; Makoto Otsuki

Background and Aims: The imbalance between synthesis and degradation of extracellular matrix (ECM) proteins is a characteristic feature in chronic pancreatitis. We evaluated the relationship between type IV collagen structure in the basement membrane (BM) and the development of acinar atrophy or the regeneration from acinar injury. Methods: Three different models of pancreatitis were induced in rats by repetitive intraperitoneal injections of 500 mg/100 g body weight of arginine (Arg) or 20 μg/kg body weight of caerulein (Cn) or a single retrograde intraductal infusion of 40 μL/100 g body weight of 3% sodium taurocholate (NaTc). We examined the changes in type IV collagen structure by immunostaining, and the serial changes in the gelatinolytic activity of pro- and active matrix metalloproteinase-2 by zymography in these models of pancreatitis. Results: The pancreas appeared to be histologically normal on day 35 after the first intraperitoneal Cn injection and on day 42 after intraductal infusion of NaTc, whereas 85% to 90% of acinar tissue was replaced by fatty tissue and dilated pancreatic ducts on day 54 after the first intraperitoneal Arg injection. Immunoreactivity for type IV collagen appeared as a discontinuous line along the BM of ducts, vessels, tubular complexes, and acinar cells on day 40 in Arg-induced pancreatitis, whereas it was detected as a continuous line along the BM on day 35 in Cn-induced pancreatitis and on day 42 in NaTc-induced pancreatitits. Gelatinolytic activity of active MMP-2 increased significantly from day 13 to day 40 after the first intraperitoneal Arg injection, whereas it decreased to the baseline level on day 35 after the first intraperitoneal Cn injection and on day 42 after intraductal infusion of NaTc. Conclusions: Our findings indicate that a long-term increase in gelatinolytic activity of active MMP-2 in Arg-induced pancreatitis causes continuous disorganization of type IV collagen in the BM and progressive acinar atrophy, whereas a transient increase in gelatinolytic activity of active MMP-2 is involved in the regeneration of type IV collagen structure in the BM and recovery from acinar injury.


Japanese Journal of Clinical Oncology | 2014

EBM-based Clinical Guidelines for Pancreatic Cancer (2013) Issued by the Japan Pancreas Society: A Synopsis

Koji Yamaguchi; Takuji Okusaka; Kyoko Shimizu; Junji Furuse; Yoshinori Ito; Keiji Hanada; Tooru Shimosegawa; Kensei Yamaguchi; Kazue Shimizu; Akihiko Nakaizumi; Takao Itoi; Nobumasa Mizuno; Takashi Hatori; Y. Yamaue; K. Hanada; Tetsuya Fujii; W. Endo; Shinichi Egawa; Yoshihiko Yokoyama; J. Furuse; Hiroaki Ohigashi; T. Nagaori; S. Kanno; Katsuhiko Uesaka; Shoko Nakamura; Yuriko Ito; Kiyoshi Shibuya; Takayuki Ohguri; Hisayasu Nagakura; Yasuyuki Kihara

Clinical practice guidelines for pancreatic cancer based on evidence-based medicine (2006) were published by the Japan Pancreas Society (Committee for revision of clinical guidelines for pancreatic cancer) in March 2009 in Japanese, revised to Clinical Practice Guidelines for Pancreatic Cancer based on evidence-based medicine (2009) in July 2009 in Japanese and further revised to Clinical Practice Guidelines for Pancreatic Cancer (2013) in October 2013 in Japanese. These guidelines were established according to evidence-based medicine. A total of 629 papers were collected from among 4612 reports concerning pancreatic cancer listed in PubMed and Igakuchuo Zasshi between May 2007 and January 2011. This new set of guidelines was written by members of the Committee for the Revision of Clinical Practice Guidelines for Pancreatic Cancer in the Japan Pancreas Society. The guidelines provide an algorithm for the diagnosis (Fig. 1) and treatment (Fig. 2) of pancreatic cancer and address six subjects (Diagnosis, Surgery, Adjuvant therapy, Radiation therapy, Chemotherapy and stent therapy), with 35 clinical questions and 57 recommendations.

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Makoto Otsuki

University of Occupational and Environmental Health Japan

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Masashi Taguchi

University of Occupational and Environmental Health Japan

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Hayato Nakamura

University of Occupational and Environmental Health Japan

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Mitsuo Tashiro

University of Occupational and Environmental Health Japan

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Shintaro Abe

University of Occupational and Environmental Health Japan

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Yoshikuni Nagashio

University of Occupational and Environmental Health Japan

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Mitsuyoshi Yamamoto

University of Occupational and Environmental Health Japan

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Akinari Tabaru

University of Occupational and Environmental Health Japan

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Hiroyuki Yoshikawa

University of Occupational and Environmental Health Japan

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