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Featured researches published by Masaaki Shimada.


Hepatology | 2007

Anti‐gp210 and anti‐centromere antibodies are different risk factors for the progression of primary biliary cirrhosis

Minoru Nakamura; Hisayoshi Kondo; Tsuyoshi Mori; Atsumasa Komori; Mutsumi Matsuyama; Masahiro Ito; Yasushi Takii; Makiko Koyabu; Terufumi Yokoyama; Kiyoshi Migita; Manabu Daikoku; Seigo Abiru; Hiroshi Yatsuhashi; Eiichi Takezaki; Naohiko Masaki; Kazuhiro Sugi; Koichi Honda; Hiroshi Adachi; Hidehiro Nishi; Yukio Watanabe; Yoko Nakamura; Masaaki Shimada; Tatsuji Komatsu; Akira Saito; Takeo Saoshiro; Hideharu Harada; Takeshi Sodeyama; Shigeki Hayashi; Akihide Masumoto; Takehiro Sando

The predictive role of antinuclear antibodies (ANAs) remains elusive in the long‐term outcome of primary biliary cirrhosis (PBC). The progression of PBC was evaluated in association with ANAs using stepwise Cox proportional hazard regression and an unconditional stepwise logistic regression model based on the data of 276 biopsy‐proven, definite PBC patients who have been registered to the National Hospital Organization Study Group for Liver Disease in Japan (NHOSLJ). When death of hepatic failure/liver transplantation (LT) was defined as an end‐point, positive anti‐gp210 antibodies (Hazard ratio (HR) = 6.742, 95% confidence interval (CI): 2.408, 18.877), the late stage (Scheuers stage 3, 4) (HR = 4.285, 95% CI:1.682,10.913) and male sex (HR = 3.266, 95% CI: 1.321,8.075) were significant risk factors at the time of initial liver biopsy. When clinical progression to death of hepatic failure/LT (i.e., hepatic failure type progression) or to the development of esophageal varices or hepatocellular carcinoma without developing jaundice (Total bilirubin < 1.5 mg/dL) (i.e., portal hypertension type progression) was defined as an end‐point in the early stage (Scheuers stage 1, 2) PBC patients, positive anti‐gp210 antibodies was a significant risk factor for hepatic failure type progression [odds ratio (OR) = 33.777, 95% CI: 5.930, 636.745], whereas positive anti‐centromere antibodies was a significant risk factor for portal hypertension type progression (OR = 4.202, 95% CI: 1.307, 14.763). Histologically, positive anti‐gp210 antibodies was most significantly associated with more severe interface hepatitis and lobular inflammation, whereas positive anticentromere antibodies was most significantly associated with more severe ductular reaction. Conclusion: These results indicate 2 different progression types in PBC, hepatic failure type and portal hypertension type progression, which may be represented by positive‐anti‐gp210 and positive‐anticentromere antibodies, respectively. (HEPATOLOGY 2007;45:118–127.)


American Journal of Human Genetics | 2012

Genome-wide Association Study Identifies TNFSF15 and POU2AF1 as Susceptibility Loci for Primary Biliary Cirrhosis in the Japanese Population

Minoru Nakamura; Nao Nishida; Minae Kawashima; Yoshihiro Aiba; Atsushi Tanaka; Michio Yasunami; Hitomi Nakamura; Atsumasai Komori; Makoto Nakamuta; Mikio Zeniya; Etsuko Hashimoto; Hiromasa Ohira; Kazuhide Yamamoto; Morikazu Onji; Shuichi Kaneko; Masao Honda; Satoshi Yamagiwa; Kazuhiko Nakao; Takafumi Ichida; Hajime Takikawa; Masataka Seike; Takeji Umemura; Yoshiyuki Ueno; Shotaro Sakisaka; Kentaro Kikuchi; Hirotoshi Ebinuma; Noriyo Yamashiki; S. Tamura; Yasuhiko Sugawara; Akira Mori

For the identification of susceptibility loci for primary biliary cirrhosis (PBC), a genome-wide association study (GWAS) was performed in 963 Japanese individuals (487 PBC cases and 476 healthy controls) and in a subsequent replication study that included 1,402 other Japanese individuals (787 cases and 615 controls). In addition to the most significant susceptibility region, human leukocyte antigen (HLA), we identified two significant susceptibility loci, TNFSF15 (rs4979462) and POU2AF1 (rs4938534) (combined odds ratio [OR] = 1.56, p = 2.84xa0× 10(-14) for rs4979462, and combined OR = 1.39, p = 2.38xa0× 10(-8) for rs4938534). Among 21 non-HLA susceptibility loci for PBC identified in GWASs of individuals of European descent, three loci (IL7R, IKZF3, and CD80) showed significant associations (combined pxa0= 3.66xa0× 10(-8), 3.66xa0× 10(-9), and 3.04xa0× 10(-9), respectively) and STAT4 and NFKB1 loci showed suggestive association with PBC (combined p = 1.11xa0× 10(-6) and 1.42xa0× 10(-7), respectively) in the Japanese population. These observations indicated the existence of ethnic differences in genetic susceptibility loci to PBC and the importance of TNF signaling and B cell differentiation for the development of PBC in individuals of European descent and Japanese individuals.


Gut | 2012

Hepatitis B virus strains of subgenotype A2 with an identical sequence spreading rapidly from the capital region to all over Japan in patients with acute hepatitis B

Yoko Tamada; Hiroshi Yatsuhashi; Naohiko Masaki; Makoto Nakamuta; Eiji Mita; Tatsuji Komatsu; Yukio Watanabe; Toyokichi Muro; Masaaki Shimada; Taizo Hijioka; Takeaki Satoh; Yutaka Mano; Toshiki Komeda; Masahiko Takahashi; Hiroshi Kohno; Hajime Ota; Shigeki Hayashi; Yuzo Miyakawa; Seigo Abiru; Hiromi Ishibashi

Objective To examine recent trends of acute infection with hepatitis B virus (HBV) in Japan by nationwide surveillance and phylogenetic analyses. Methods During 1991 through 2009, a sentinel surveillance was conducted in 28 national hospitals in a prospective cohort study. Genotypes of HBV were determined in 547 patients with acute hepatitis B. Nucleotide sequences in the preS1/S2/S gene of genotype A and B isolates were determined for phylogenetic analyses. Results HBV genotype A was detected in 137 (25% (accompanied by genotype G in one)) patients, B in 48 (9%), C in 359 (66%), and other genotypes in the remaining three (0.5%). HBV persisted in five with genotype A including the one accompanied by genotype G; another was co-infected with HIV type 1. The genotype was A in 4.8% of patients during 1991–1996, 29.3% during 1997–2002, and 50.0% during 2003–2008 in the capital region, as against 6.5%, 8.5% and 33.1%, respectively, in other regions. Of the 114 genotype A isolates, 13 (11.4%) were subgenotype A1, and 101 (88.6%) were A2, whereas of the 43 genotype B isolates, 10 (23.3%) were subgenotype B1, 28 (65.1%) were B2, two (4.7%) were B3, and three (7.0%) were B4. Sequences of 65 (64%) isolates of A2 were identical, as were three (23%) of A1, and five (18%) of B2, but none of the B1, B3 and B4 isolates shared a sequence. Conclusions Acute infection with HBV of genotype A, subgenotype A2 in particular, appear to be increasing, mainly through sexual contact, and spreading from the capital region to other regions in Japan nationwide. Infection persisted in 4% of the patients with genotype A, and HBV strains with an identical sequence prevailed in subgenotype A2 infections. This study indicates the need for universal vaccination of young people to prevent increases in HBV infection in Japan.


Journal of Gastroenterology | 2011

Genetic polymorphisms in CTLA4 and SLC4A2 are differentially associated with the pathogenesis of primary biliary cirrhosis in Japanese patients

Yoshihiro Aiba; Minoru Nakamura; Satoru Joshita; Tatsuo Inamine; Atsumasa Komori; Kaname Yoshizawa; Takeji Umemura; Hitomi Horie; Kiyoshi Migita; Hiroshi Yatsuhashi; Makoto Nakamuta; Nobuyoshi Fukushima; Takeo Saoshiro; Shigeki Hayashi; Hiroshi Kouno; Hajime Ota; Toyokichi Muro; Yukio Watanabe; Yoko Nakamura; Toshiki Komeda; Masaaki Shimada; Naohiko Masaki; Tatsuji Komatsu; Michiyasu Yagura; Kazuhiro Sugi; Michiaki Koga; Kazuhiro Tsukamoto; Eiji Tanaka; Hiromi Ishibashi

BackgroundAnti-gp210 and anti-centromere antibodies are different risk factors for the progression of primary biliary cirrhosis (PBC). In order to dissect the genetic basis for the production of these autoantibodies, as well as the development and progression of PBC in Japanese patients, we examined single nucleotide polymorphisms (SNPs) in cytotoxic T-lymphocyte antigen 4 (CTLA4) and solute carrier family 4 anion exchanger, member 2 (SLC4A2), which have been associated with the pathogenesis of PBC in Caucasian patients.MethodsFour SNPs for both CTLA4 and SLC4A2 were genotyped, using the polymerase chain reaction–restriction fragment length polymorphism method and TaqMan assay, in 450 Japanese PBC patients and 371 sex-matched healthy controls.ResultsThe CTLA4 rs231775, rs3087243, and rs231725 SNPs were significantly associated with PBC susceptibility. The CTLA4 rs231725 SNP was significantly associated with progression to late-stage disease. The CTLA-4 haplotype 1 (rs231775 G, rs231777 C, rs3087243 G, rs231725 A; GCGA) was a risk factor for PBC susceptibility but a protective factor for PBC progression. Conversely, the CTLA-4 haplotype 2 (ACAG) was a protective and risk factor, respectively, for PBC susceptibility and progression. In addition, the CTLA4 rs231777 SNP and haplotype 3 (ATGG) was significantly associated with anti-gp210 antibody production, while SLC4A2 haplotype 4 (rs2069443 A, rs2303933 G, rs2303937 A, rs2303941 T; AGAT) and haplotype 3 (AAGC) were significantly associated with PBC susceptibility and anti-centromere antibody production, respectively.ConclusionsCTLA4 and SLC4A2 genetic polymorphisms are differentially associated with PBC development and progression, as well as anti-gp210 or anti-centromere antibody production, in Japanese PBC patients.


Liver International | 2012

Hepatocellular carcinoma and survival in patients with autoimmune hepatitis (Japanese National Hospital Organization-autoimmune hepatitis prospective study)

Kiyoshi Migita; Yukio Watanabe; Yuka Jiuchi; Yoko Nakamura; Akira Saito; Michiyasu Yagura; Hajime Ohta; Masaaki Shimada; Eiji Mita; Taizo Hijioka; Haruhiro Yamashita; Eiichi Takezaki; Toyokichi Muro; Hironori Sakai; Makoto Nakamuta; Seigo Abiru; Atsumasa Komori; Masahiro Ito; Hiroshi Yatsuhashi; Minoru Nakamura; Hiromi Ishibashi

Although the outcome of autoimmune hepatitis (AIH) is generally good, the natural course and likelihood of progression to cirrhosis or hepatocellular carcinoma (HCC) remain undefined, and may vary by region and population structure. Our aims were to evaluate risk factors that contribute to poor outcome and particularly development of HCC in a prospective multicentric cohort study of AIH.


Journal of Gastroenterology | 2002

Possible involvement of neutrophil elastase in impaired mucosal repair in patients with ulcerative colitis

Yuji Kuno; Kenji Ina; Tsuyoshi Nishiwaki; Tomoyuki Tsuzuki; Masaaki Shimada; Akira Imada; Yuji Nishio; Kazuo Nobata; Takefumi Suzuki; Takafumi Ando; Kenji Hibi; Akimasa Nakao; Tadashi Yokoyama; Yasuhisa Yokoyama; Kazuo Kusugami

Background. Little information is available on the relative contribution of peptide growth factors and leukocyte-derived proteinases to the repair processes in inflammatory bowel disease (IBD). We investigated their possible roles in epithelial cell restitution and proliferation in patients with IBD. Methods. The expression of hepatocyte growth factor (HGF), keratinocyte growth factor (KGF), transforming growth factor-β (TGF-β), and neutrophil elastase (NE) was examined in colonic mucosal tissues. The effects of organ culture supernatants of mucosal tissues on epithelial cell restitution and proliferation were analyzed in vitro using an intestinal cell line, IEC-6 cells. Results. Most organ cultures detected the presence of measurable levels of HGF, with a relative paucity of KGF and TGF-β activity. Greater levels of HGF were obtained in the mucosa involved with IBD, especially in patients with ulcerative colitis (UC). The mucosa involved with UC also showed higher amounts of NE. The supernatants from the mucosa involved with UC possessed a prominent stimulatory effect on the restitution of IEC-6 cells. By contrast, significant suppression beyond baseline levels was observed for the proliferation of IEC-6 cells when they were incubated with recombinant HGF plus the supernatants from the mucosa involved with UC. This suppression was diminished considerably by preincubation of the supernatants with the anti-NE antibody. Conclusions. HGF produced in the intestinal mucosa may be an important stimulator acting on epithelial cell restitution in patients with IBD. However, NE released in situ may impair mucosal repair through inhibiting epithelial cell proliferation in patients with UC.


Inflammatory Bowel Diseases | 2002

Suppressive effects of cyclosporine A on neutrophils and T cells may be related to therapeutic benefits in patients with steroid-resistant ulcerative colitis

Kenji Ina; Kazuo Kusugami; Masaaki Shimada; Tomoyuki Tsuzuki; Yuji Nishio; David G. Binion; Akira Imada; Takafumi Ando

An intravenous infusion of cyclosporine A (CsA) shows clinical benefits in patients with steroid-resistant ulcerative colitis (UC). To clarify its mechanisms, we investigated the ability of CsA to inhibit the functions of neutrophils and T cells. The cytotoxic activity by mucosal T cells was analyzed by anti-CD3-triggered cytotoxicity after lamina propria mononuclear cells were cultured with recombinant interleukin (IL)-2. The chemotactic response, the generation of superoxide, and the production of chemokines, IL-8, and macrophage inflammatory protein-1&agr; by neutrophils were examined using a multiple-well chamber assay, a chemiluminescence method, and an enzyme-linked immunosorbent assay (ELISA), respectively. Mucosal chemokine activity was determined by an ELISA using the organ culture supernatant of mucosal biopsy tissues. Pretreatment with CsA caused consistent inhibitions of cytotoxic activity by mucosal T cells and chemotactic migration, superoxide generation, and chemokine production by neutrophils mostly in a dose-dependent manner. In patients who received an intravenous infusion of CsA, mucosal chemokine activity decreased after therapy in parallel with decreases in the numbers of neutrophils and mononuclear cells in the biopsy tissues. These results suggest that suppressive effects of CsA on neutrophils and T cells may be related to therapeutic benefits in patients with steroid-resistant UC.


PLOS ONE | 2015

Circulating microRNA Profiles in Patients with Type-1 Autoimmune Hepatitis

Kiyoshi Migita; Atsumasa Komori; Hideko Kozuru; Yuka Jiuchi; Minoru Nakamura; Michio Yasunami; Hiroshi Furukawa; Seigo Abiru; Kazumi Yamasaki; Shinya Nagaoka; Satoru Hashimoto; Shigemune Bekki; Hiroshi Kamitsukasa; Yoko Nakamura; Hajime Ohta; Masaaki Shimada; Hironao Takahashi; Eiji Mita; Taizo Hijioka; Haruhiro Yamashita; Hiroshi Kouno; Makoto Nakamuta; Keisuke Ario; Toyokichi Muro; Hironori Sakai; Kazuhiro Sugi; Hideo Nishimura; Kaname Yoshizawa; Takeaki Sato; Atsushi Naganuma

Recent studies have demonstrated that micro (mi)RNA molecules can be detected in the circulation and can serve as potential biomarkers of various diseases. This study used microarray analysis to identify aberrantly expressed circulating miRNAs in patients with type 1 autoimmune hepatitis (AIH) compared with healthy controls. Patients with well-documented and untreated AIH were selected from the National Hospital Organization (NHO)-AIH-liver-network database. They underwent blood sampling and liver biopsy with inflammation grading and fibrosis staging before receiving treatment. To further confirm the microarray data, circulating expression levels of miR-21 and miR-122 were quantified by real-time quantitative polymerase chain reaction in 46 AIH patients, 40 patients with chronic hepatitis C (CHC), and 13 healthy controls. Consistent with the microarray data, serum levels of miR-21 were significantly elevated in AIH patients compared with CHC patients and healthy controls. miR-21 and miR-122 serum levels correlated with alanine aminotransferase levels. Circulating levels of miR-21 and miR-122 were significantly reduced in AIH patients with liver cirrhosis, and were inversely correlated with increased stages of fibrosis. By contrast, levels of circulating miR-21 showed a significant correlation with the histological grades of inflammation in AIH. We postulate that aberrantly expressed serum miRNAs are potential biomarkers of AIH and could be implicated in AIH pathogenesis. Alternations of miR-21 and miR-122 serum levels could reflect their putative roles in the mediation of inflammatory processes in AIH.


PLOS ONE | 2013

Association of STAT4 Polymorphisms with Susceptibility to Type-1 Autoimmune Hepatitis in the Japanese Population

Kiyoshi Migita; Minoru Nakamura; Seigo Abiru; Yuka Jiuchi; Shinya Nagaoka; Atsumasa Komori; Satoru Hashimoto; Shigemune Bekki; Kazumi Yamasaki; Tatsuji Komatsu; Masaaki Shimada; Hiroshi Kouno; Taizo Hijioka; Motoyuki Kohjima; Makoto Nakamuta; Michio Kato; Kaname Yoshizawa; Hajime Ohta; Yoko Nakamura; Eiichi Takezaki; Hideo Nishimura; Takeaki Sato; Keisuke Ario; Noboru Hirashima; Yukio Oohara; Atsushi Naganuma; Toyokichi Muro; Hironori Sakai; Eiji Mita; Kazuhiro Sugi

Background/Aims Recent studies demonstrated an association of STAT4 polymorphisms with autoimmune diseases including systemic lupus erythematosus and rheumatoid arthritis, indicating multiple autoimmune diseases share common susceptibility genes. We therefore investigated the influence of STAT4 polymorphisms on the susceptibility and phenotype of type-1 autoimmune hepatitis in a Japanese National Hospital Organization (NHO) AIH multicenter cohort study. Methodology/Principal Findings Genomic DNA from 460 individuals of Japanese origin including 230 patients with type-1 autoimmune hepatitis and 230 healthy controls was analyzed for two single nucleotide polymorphisms in the STAT4 gene (rs7574865, rs7582694). The STAT4 rs7574865T allele conferred risk for type-1 autoimmune hepatitis (ORu200a=u200a1.61, 95% CIu200a=u200a1.23–2.11; Pu200a=u200a0.001), and patients without accompanying autoimmune diseases exhibited an association with the rs7574865T allele (ORu200a=u200a1.50, 95%CIu200a=u200a1.13–1.99; Pu200a=u200a0.005). Detailed genotype-phenotype analysis of type-1 autoimmune hepatitis patients with (nu200a=u200a44) or without liver cirrhosis (nu200a=u200a186) demonstrated that rs7574865 was not associated with the development of liver cirrhosis and phenotype (biochemical data and the presence of auto-antibodies). Conclusions/Significance This is the first study to show a positive association between a STAT4 polymorphism and type-1 autoimmune hepatitis, suggesting that autoimmune hepatitis shares a gene commonly associated with risk for other autoimmune diseases.


Digestion | 2000

Helicobacter pylori-Associated Gastric Ulcer Exhibits Enhanced Mucosal Chemokine Activity at the Ulcer Site

Tatsuji Shimizu; Kazuo Kusugami; Kenji Ina; Akira Imada; Yuji Nishio; Takehiko Hosokawa; Masahiro Ohsuga; Masaaki Shimada; Mitsuhiro Noshiro; Hiroshi Kaneko; Takafumi Ando

Background and Aim: Although mucosal α- and β-chemokines are considered to be involved in the pathogenesis of Helicobacter pylori-associated gastritis, little is known how these chemokines are related to the ulcerogenesis in peptic ulcer patients. We examined the levels of interleukin (IL)-8 and macrophage inflammatory protein-1α (MIP-1α) in organ cultures and the numbers of inflammatory cells infiltrating the lamina propria by using the mucosal tissues obtained from gastric ulcer (GU) patients with and without H. pylori infection. Methods: Levels of IL-8 and MIP-1α secreted in organ cultures were measured by an enzyme-linked immunosorbent assay. Numbers of myeloperoxidase-positive neutrophils, CD68-positive macrophages, and mononuclear cells were determined in tissue sections. Results: The mucosal tissues of both the gastric antrum and the ulcer site obtained from patients with H. pylori-positive GU showed significantly higher levels of IL-8 and MIP-1α and increased numbers of inflammatory cells compared with the corresponding mucosal tissues from those with H. pylori-negative GU or the antral mucosal tissues from H. pylori-negative controls. When the values were compared between the mucosal tissues from the gastric antrum and those from the ulcer site, the latter group of tissues showed significantly higher levels of IL-8 and MIP-1α and increased numbers of neutrophils and macrophages than the former group regardless of its healing process in patients with H. pylori-positive GU. Conclusion: Mucosal α- and β-chemokines may be important to the ulcerogenesis in H. pylori-associated GU disease.

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Kiyoshi Migita

Fukushima Medical University

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Yoko Nakamura

Tokyo Medical and Dental University

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