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Featured researches published by Takuya Nagano.


Journal of Clinical Immunology | 1999

Cytokine profile in the liver of primary biliary cirrhosis.

Takuya Nagano; Kazuhide Yamamoto; Seiji Matsumoto; Ryoichi Okamoto; Masafumi Tagashira; Naofumi Ibuki; Shuji Matsumura; Kazuhisa Yabushita; Nobuaki Okano; Takao Tsuji

We characterized the cytokine profile in the liver of patients with primary biliary cirrhosis (PBC). Total RNA was extracted from the biopsy specimens of 9 patients with early-stage PBC, 10 with chronic hepatitis C (CHC), and 4 normal controls. cDNA was prepared and amplified with a polymerase chain reaction using primers for interferon (IFN)-γ and interleukin (IL)-2, -4, -5, -6, -10, -12 (p40), and -15. Cytokines such as IFN-γ and IL-5, -6, -10, -12, and -15 were expressed in most cases of PBC. Expression rates of IL-5 and IL-6 were higher than in CHC and controls. The higher expression rate of IL-5 in PBC was associated with eosinophil infiltration. IL-2 and IL-4 were rarely detected. Semiquantitative analysis revealed that the expression of IFN-γ and IL-10 was reversed in PBC and CHC: high IFN-γ and low IL-10 in PBC and high IL-10 and low IFN-γ in CHC. These results suggest that cytokine expression is skewed in PBC and both Th1 and Th2 cytokines may play a role in the pathogenesis.


Journal of Clinical Immunology | 2000

Expression of Perforin and Fas Ligand mRNA in the Liver of Viral Hepatitis

Masafumi Tagashira; Kazuhide Yamamoto; Kozo Fujio; Takuya Nagano; Ryoichi Okamoto; Naofumi Ibuki; Kazuhisa Yabushita; Shuji Matsumura; Nobuaki Okano; Takao Tsuji

Cytotoxic T lymphocytes (CTLs) play an important role in the pathogenesis of viral hepatitis. We studied the expression of mRNAs of perforin and Fas ligand (Fas-L) in biopsy specimens from chronic hepatitis B (CHB) (15 cases) and hepatitis C (CHC) patients (13 cases). Both perforin and Fas-L mRNAs were detected in all cases of both CHB and CHC. No messages were detected in the control livers from two cases of fatty liver, a case of Gilberts syndrome, and a case of Dubin–Johnson syndrome. Semiquantitative analysis revealed a positive correlation between the intensity of perforin and Fas-L mRNAs in both CHB and CHC. In CHB, the intensity of both perforin and Fas-L mRNAs showed a positive correlation with the histological activity and serum alanine aminotransferase level, while the correlation was not apparent in CHC. These results suggest that both perforin and Fas/Fas-L systems are involved in the pathogenesis of liver cell injury of CHB and CHC.


Journal of Gastroenterology and Hepatology | 1995

Activated liver macrophages in human liver diseases

Kazuhide Yamamoto; Masaki Ohmoto; Seiji Matsumoto; Takuya Nagano; Haruhiko Kobashi; Ryoichi Okamoto; Takao Tsuji

Immunohistochemical analysis using monoclonal antibodies specific for cells of monocyte/macrophage lineage reveals that resident liver macrophages have a phenotype distinct from that of monocytes or activated liver macrophages. Liver macrophages consist of heterogeneous cell populations in maturation (matured 25F9‐positive and immature 25F9‐negative) but the ratio of two populations is constant in normal and diseased livers. The expression of CD 14 is down‐regulated in resident liver macrophages as compared to that in monocytes, while the expression of 25F9 is up‐regulated. On the other hand, the expressions of CD 14 and Fc γ RI are up‐regulated in activated liver macrophages in viral and autoimmune hepatitis. In vitro culture of monocytes in medium without cytokines induces the phenotype similar to that of resident liver macrophages. Addition of macrophage‐colony stimulating factor or interferon‐γ into the culture medium induces the expression of Fc γ RI, the phenotype of which resembles that of activated liver macrophages. These results suggest that liver macrophages consist of heterogeneous cell populations and that both phenotype and function are affected by the local milieu of cytokines.


Journal of Clinical Pathology | 2016

Association of hepatic oxidative stress and iron dysregulation with HCC development after interferon therapy in chronic hepatitis C

Shintaro Nanba; Fusao Ikeda; Nobuyuki Baba; Koichi Takaguchi; Tomonori Senoh; Takuya Nagano; Hiroyuki Seki; Yasuto Takeuchi; Yuki Moritou; Tetsuya Yasunaka; Hideki Ohnishi; Yasuhiro Miyake; Akinobu Takaki; Kazuhiro Nouso; Yoshiaki Iwasaki; Kazuhide Yamamoto

Background Oxidative stress may play pathogenic roles in the mechanisms underlying chronic hepatitis C (CHC). The impact of excessive oxidative stress and iron dysregulation on the development of hepatocellular carcinoma (HCC) after interferon therapy has not been established. Methods We investigated the impact of oxidative stress and iron deposition on HCC development after therapy with pegylated interferon (PegIFN)+ribavirin in CHC patients. Systemic and intracellular iron homeostasis was evaluated in liver tissues, peripheral blood mononuclear cells and sera. Results Of 203 patients enrolled, 13 developed HCC during the 5.6-year follow-up. High hepatic 8-hydroxy-2-deoxyguanosine (8-OHdG) levels were significantly associated with HCC development in multivariate analysis (p=0.0012) which was also significantly correlated with severity of hepatic iron deposition before therapy (p<0.0001). Systemic and intracellular iron regulators of hepcidin and F-box and leucine-rich repeat protein 5 (FBXL5) expression levels were significantly suppressed in CHC patients (p=0.0032 and p=0.016, respectively) despite their significantly higher levels of serum iron and ferritin compared with controls. However, intracellular iron regulators of FBXL5 and iron regulatory proteins were regulated in balance with hepatic iron deposition. Significant correlations were observed among IL-6, bone morphogenetic protein 6, hepcidin and ferroportin, as regards systemic iron regulation. Conclusions Measurement of hepatic oxidative stress before antiviral therapy is useful for the prediction of HCC development after interferon therapy. Low baseline levels of the intracellular iron regulators of FBXL5 in addition to a suppressed hepcidin level might be associated with severe hepatic iron deposition in CHC patients. Trial registration number UMIN 000001031.


Oncology | 2017

Hand-Foot Syndrome and Post-Progression Treatment Are the Good Predictors of Better Survival in Advanced Hepatocellular Carcinoma Treated with Sorafenib: A Multicenter Study

Chikara Ogawa; Masahiro Morita; Akina Omura; Teruyo Noda; Atsushi Kubo; Toshihiro Matsunaka; Hiroyuki Tamaki; Mitsushige Shibatoge; Akemi Tsutsui; Tomonori Senoh; Takuya Nagano; Kouichi Takaguchi; Joji Tani; Asahiro Morishita; Hirohito Yoneyama; Tsutomu Masaki; Akio Moriya; Masaharu Ando; Akihiro Deguchi; Yasutaka Kokudo; Yasunori Minami; Kazuomi Ueshima; Toshiharu Sakurai; Naoshi Nishida; Masatoshi Kudo

Objective: To determine the relationship between treatment outcomes and hand-foot syndrome (HFS), and the relationship between survival rate and post-progression treatment after sorafenib therapy. Methods: The study assessed 314 patients with advanced hepatocellular carcinoma (HCC) treated with sorafenib at 5 general hospitals in Kagawa Prefecture, Japan. Results: At the start of sorafenib therapy, 23.6% of the patients had HCC of a Child-Pugh class other than A. The initial sorafenib dose was 800 mg in 9.2% of the patients and 400 mg in 64.3%. Time to progression was 129 days (95% CI: 87.3-170.7) and the median overall survival (OS) was 392 days (95% CI: 316.0-468.0). The OS of the patients with Child-Pugh class A HCC was significantly better than that of the patients with Child-Pugh class B HCC (p < 0.0001). The survival curves for Child-Pugh class A-5 points and class A-6 points were significantly different, with that for class A-5 points being better (p < 0.0001). A significant difference was observed between the patients who exhibited HFS and those who did not, with the former exhibiting a better survival rate (p < 0.001). In addition, the survival rate of the patients who received post-progression treatment after sorafenib therapy was significantly better than that of the patients who did not (p < 0.001). Conclusion: In sorafenib therapy, patients with HFS and those who received post-progression treatment exhibited good OS.


Hepatology Research | 2008

A model for estimating cirrhosis in patients with type 1 autoimmune hepatitis

Yasuhiro Miyake; Yoshiaki Iwasaki; Ryo Terada; Takuya Nagano; Haruhiko Kobashi; Kohsaku Sakaguchi; Yasushi Shiratori

Aim:  Longstanding cirrhosis has been recognized as a risk factor for the development of hepatocellular carcinoma in patients with autoimmune hepatitis (AIH). Thus, the accurate determination of cirrhosis is important for prognostication, decisions regarding treatment and monitoring of disease progression. The aim of this study was to identify independent predictors of cirrhosis and to develop a model for estimating cirrhosis in patients with type 1 AIH.


Digestive Endoscopy | 1995

Diagnostic Accuracy of Laparoscopic Liver Biopsy in Chronic Liver Diseases, Comparison of Laparoscopic and US‐Guided Liver Biopsy Results

Toshio Ito; Minora Ukida; Kazuhide Yamamoto; Haruhiko Kobashi; Youichi Morimoto; Masayuki Mikami; Masaki Omoto; Sousuke Nakanishi; Kanji Shinmen; Takuya Nagano; Seiji Matsumoto; Masaki Nakamura; Ryoichi Okamoto; Shinichi Fujioka; Nobuhiko Omori; Kozo Ujike; Hidenori Shiraha; Takao Tsuji

Liver biopsies were carried out using three different needles, a Vim‐Silverman needle 2.5 mm in outer caliber, an 18‐Gauge (18G) Majima needle, and a 17‐Gauge (17G) Majima needle. The biopsies were obtained from nearby locations on the liver surface under laparoscopic observation, to ascertain differences in histological diagnosis according to the size of the biopsy specimen. The biopsy specimens obtained with the Vim‐Silverman needle were wider than those obtained with the other two needles. The agreement in histological diagnoses of the liver, obtained with the Vim‐Silverman needle versus the 18G Majima needle, was 26.0%, while that between the Vim‐Silverman needle and the 17G Majima needle was 40.0%. Histological diagnosis tended to be underestimated in small biopsy specimens in advanced chronic liver diseases. A questionnaire survey, conducted in 92 hospitals affiliated with Okayama University Medical School, revealed US‐guided liver biopsy to be the practice of choice in 57 of 92 (62.0%) hospitals, and 18G needles were used in US‐guided liver biopsy in 35 of 78 (45.2%) hospitals.


Digestive Diseases | 2017

Clinicopathological Study of Autoimmune Hepatitis Cases That Were Difficult to Differentiate from Drug-Induced Liver Injury

Akemi Tsutsui; Kenichi Harada; Koichi Tsuneyama; Tomonori Senoh; Takuya Nagano; Koichi Takaguchi; Midori Ando; Satoko Nakamura; Koichi Mizobuchi; Masatoshi Kudo

Aim: Acute-onset autoimmune hepatitis (AIH) histopathologically presents with features of acute hepatitis and lacks a specific diagnostic method. Also, AIH is often difficult to differentiate from drug-induced liver injury (DILI). We aimed to investigate the final clinical diagnosis of these cases, and compare the clinical, biochemical, and histological characteristics of AIH vs. DILI. Methods: We examined the Digestive Disease Week Japan 2004 (DDW-J) scale scores, AIH scores, clinical data, and pathological findings in 20 patients in whom it was difficult to differentiate autoimmune liver disease from DILI. Results: In cases with a DDW-J scale score of ≥5, there was a good correlation between the final diagnosis and DDW-J scale assessments, but in cases with a DDW-J scale score of ≦4 they did not correlate well. The scores for pathological findings, such as cobblestone hepatocellular change (p = 0.015), interface hepatitis (p = 0.012), and prominent plasma cells in portal areas (p = 0.011), were higher in the AIH group than in the DILI group. Conclusion: This study showed that DDW-J scale was useful for differentiating AIH from DILI in cases with a DDW-J scale score of ≧5. The histologic features of AIH were characterized by cobblestone hepatocellular change, interface hepatitis, and plasma cell infiltration of the portal region.


Mediators of Inflammation | 2015

Comparison of Liver Biopsy Findings with the Digestive Disease Week Japan 2004 Scale for Diagnosis of Drug-Induced Liver Injury

Akemi Tsutsui; Yasuni Nakanuma; Kouichi Takaguchi; Satoko Nakamura; Hiroshi Shibata; Nobuyuki Baba; Tomonori Senoh; Takuya Nagano; Hiroko Ikeda

The liver biopsy remains a valuable tool in the diagnosis of drug-induced liver injury (DILI). The Digestive Disease Week Japan 2004 (DDW-J) scale proposed as an objective tool for the diagnosis of DILI has been widely used in Japan. So far, the histological features have not been compared with DDW-J scale in detail. Herein, we examined the correlation between liver biopsy findings and clinical features, particularly DDW-J scales. A total of 80 patients with liver injuries of unknown cause were enrolled. Based on the histological findings, these cases were categorized into 3 groups: A (DILI was strongly suspected), B (DILI was suspected), and C (DILI should be considered in the differential diagnosis). Histological groups and DDW-J scale were moderately correlated (κ = 0.60). The mean total DDW-J scale scores were as follows: 4.89 for A, 3.26 for B, and 0.75 for C (p < 0.05). While hepatocellular type was coincided in a majority of cases by histological and DDW-J scale evaluation, cholestatic type was not well coincided. In conclusion, biopsy findings and DDW-J scale were well correlated, and the hepatocellular type of liver injuries was well coincided by both evaluations, though there were several discrepant cases, particularly in cholestatic type.


Liver | 1999

Immunohistochemical study on phenotypical changes of hepatocytes in liver disease with reference to extracellular matrix composition

Seiji Matsumoto; Kazuhide Yamamoto; Takuya Nagano; Ryoichi Okamoto; Naohisa Ibuki; Masafumi Tagashira; Takao Tsuji

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