Yumiko Nagao
Kurume University
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Featured researches published by Yumiko Nagao.
The American Journal of Gastroenterology | 2007
Takumi Kawaguchi; Tatsuya Ide; Eitaro Taniguchi; Eiichi Hirano; Minoru Itou; Shuji Sumie; Yumiko Nagao; Chikatoshi Yanagimoto; Shinichiro Hanada; Hironori Koga; Michio Sata
OBJECTIVES:Hepatitis C virus (HCV) infection is linked to greater insulin resistance. Although HCV itself is a candidate for the development of insulin resistance, the effects of antiviral treatment on impaired glucose metabolism remain unclear. The aim of this study is to examine the effects of clearance of HCV on insulin resistance, beta-cell function, and hepatic expression of insulin receptor substrate (IRS)1/2, central molecules for insulin signaling.METHODS:We analyzed 89 biopsy-proven patients with chronic HCV infection. Patients received interferon-α or interferon-α plus ribavirin for 6 months and were classified into three groups at 6 months after the conclusion of antiviral therapy according to their response to antiviral therapy: sustained responders (N = 29), relapsers (N = 12), and nonresponders (N = 48). Insulin resistance and beta-cell function were assessed by the homeostasis model assessment method (HOMA-IR and HOMA-%B, respectively). Hepatic expression of IRS1/2 was evaluated by immunoblotting and immunostaining in 14 sustained responders.RESULTS:In nonresponders and relapsers, there were no significant changes in HOMA-IR and HOMA-%B values after antiviral therapy. On the other hand, in sustained responders, HOMA-IR values significantly decreased to 1.7 ± 0.8 from 3.1 ± 1.1 (P < 0.05) after antiviral therapy. Similarly, HOMA-%B values significantly decreased to 90.6 ± 10.0 from 113.7 ± 15.3 (P < 0.05). Immunoblotting showed a threefold increase in IRS1/2 expression after clearance of HCV. Immunostaining revealed that greater IRS1/2 expression was seen in hepatocytes.CONCLUSIONS:We showed that clearance of HCV improves insulin resistance, beta-cell function, and hepatic IRS1/2 expression.
Journal of Gastroenterology and Hepatology | 2004
Yumiko Nagao; Michio Sata
Hepatitis C virus (HCV) is an important factor in the development of chronic liver disease and hepatocellular carcinoma. In recent years it has become known that HCV induces various extrahepatic manifestations including mixed cryoglobulinemia, membranoproliferative glomerulonephritis, Sjögrens syndrome, autoimmune thyroiditis, malignant lymphoma, porphyria cutanea tarda and lichen planus. Although the mechanisms of extrahepatic manifestations remain unclear, it is known that interferon (IFN) therapy and coadministration of IFN with ribavirin are effective in promoting the disappearance or alleviation of such extrahepatic lesions, which have tended to be overlooked. The present review focuses on lichen planus, one of the major extrahepatic manifestations.
Liver International | 2007
Takumi Kawaguchi; Eitaro Taniguchi; Minoru Itou; Shuji Sumie; Tetsuharu Oriishi; Hisako Matsuoka; Yumiko Nagao; Michio Sata
Hepatitis C virus (HCV) infection causes insulin resistance. Because increased insulin resistance is a risk factor for development of hepatocellular carcinoma and reduced long‐term survival, insulin resistance is a therapeutic target in patients with HCV infection. Branched‐chain amino acids (BCAAs) are not only structural constituents of proteins but they are also considered as regulators of insulin signalling. We first describe two cases suggesting that administration of BCAAs improves insulin resistance associated with HCV‐related liver disease. Although there were no changes in body weight, plasma glucose concentration and haemoglobin A1c (HbA1c) value were decreased. Moreover, BCAAs caused a decrease in both fasting insulin concentration and the value of homeostasis model assessment for insulin resistance. Thus, BCAAs are a potential therapeutic agent for improving insulin resistance in patients with HCV‐related liver disease.
Hepatology Research | 2002
Yumiko Nagao; Junko Tanaka; Toshio Nakanishi; Takashi Moriya; Keiko Katayama; Junko Kumagai; Yutaka Komiya; Yuji Itoh; Yoshinari Myoken; Megumu Fujihara; Michio Sata; Hiroshi Yoshizawa
We previously investigated the incidence of extrahepatic manifestations including oral precancerous disease among the inhabitants in a hepatitis C virus (HCV) hyperendemic area in Fukuoka in Japan. The present study design was based on a prospective cohort at the other HCV hyperendemic area. One oral surgeon examined the oral lesions of 59 adult inhabitants (21 men, 38 women; mean age of 70.7 years), of a hyperendemic area of HCV infection. Furthermore, all subjects were interviewed regarding the natural history of extrahepatic manifestations. All sera were examined for antibodies to HCV (anti-HCV), serum HCV RNA, HCV genotype, antinuclear antibody (ANA), rheumatoid factor (RF) activity, and anti-SS-A and-B antibodies. Anti-HCV or HCV RNA was detected in sera from 59 (100%) or 57 (96.7%) of all subjects. Oral lichen planus (OLP), leukoplakia with leukoedema, or only leukoedema was observed in 8 (8.5%), 1 (1.7%), or 2 (3.4%) subjects, respectively. The incidence of all subjects with one or more HCV-related extrahepatic manifestation was 66.1% (39/59). The subjects with dry mouth were 25.4% (15/59). There was no relation among these autoantibodies, symptoms of dry mouth, or prevalence of HCV-associated extrahepatic manifestations. These findings demonstrate that the inhabitants with HCV infection showed various extrahepatic manifestations, and was not always limited to specific HCV areas.
Journal of Gastroenterology and Hepatology | 2008
Yumiko Nagao; Katsuya Kawasaki; Michio Sata
Background and Aim: Hepatitis C virus (HCV) causes liver diseases and extrahepatic manifestations, and also contributes to insulin resistance and type 2 diabetes mellitus (DM). The aims of the present study were to examine the incidence of extrahepatic manifestations including lichen planus in HCV‐infected patients and to evaluate the relationship between lichen planus and insulin resistance.
Hepatitis Monthly | 2014
Yumiko Nagao; Yuji Kawahigashi; Michio Sata
Background: Periodontal disease and systemic health are closely associated. However, there is no data supporting the association between periodontal disease and patients with liver diseases associated with hepatitis C virus (HCV) and/or hepatitis B virus (HBV) infection. Objectives: The aim of this study was to evaluate the association between periodontitis and progression of liver diseases in patients with HCV and/or HBV infection. Patients and Methods: In this retrospective study, 351 patients with HCV- and/or HBV-related liver diseases underwent screening for periodontal disease using the Salivaster® salivary occult blood test from February 2010 to June 2014. Furthermore, we examined the prevalence of fimbrillin (fimA) genotype of Porphyromonas gingivalis (P. gingivalis) in 28 HCV-infected patients visited at our hospital between January 2013 and June 2014. P. gingivalis with fimA genotype with types I to V was further detected using a PCR method. Results: Of 351 patients, 76 patients (group 1) had a strong positive result for salivary occult blood test and 275 patients (group 2) had weak positive or negative test results. Significant factors between the groups were obesity, level of AST, ALT, LDH, ALP, Alb, D.Bil, T.cho, AFP, platelets (Plt), IRI, HOMA-IR, current interferon (IFN) treatment and the daily frequency of tooth brushing. Between-groups analysis indicated that total protein (T.pro) level and liver fibrosis were significant factors. According to multivariate analysis, five factors were associated with periodontal disease as Plt count below 80000, brushing teeth only once a day, current IFN treatment, aged 65 years or older and obesity. The adjusted odds ratios for these five factors were 5.80, 3.46, 2.87, 2.50 and 2.33, respectively, and each was statistically significant. Twenty-eight saliva specimens had positive results for P. gingivalis with fimA genotype types I to V. The prevalence of fimA genotype II was higher in 14 patients with liver cirrhosis or a history of hepatocellular carcinoma treatment (group B, 50.00%) than 14 patients with only hepatitis C (group A, 21.43%). Conclusions: Periodontitis might be associated with progression of viral liver disease; hence, controlling oral disease is essential for the prevention and management of liver fibrosis.
Virology Journal | 2010
Yumiko Nagao; Michio Sata
BackgroundHypoalbuminemia has been shown to be associated with increased mortality. We reported a mass screening in 1990 of X town in Japan, which demonstrated a high prevalence of hepatitis C virus (HCV) infection. This follow-up study determined, through a period of 12 years, whether serum albumin levels impact on the life prognosis of the residents of X town.ResultsOf the 509 subjects, 69 had died and 55 had moved to other regions by 2002. Therefore, we analyzed 454 people for whom we could confirm life and death between 1990 and 2002. Albumin levels were assigned to two groups, low (<4.0 g/L, group A) and normal (≥4.0 g/L, group B). Of the 454 subjects analyzed, 25 were in group A and 429 in group B and the mortality was 68.0% (17/25 cases, P < 0.00001 vs. group B) and 12.1% (52/429), respectively. Mortality from hepatocellular carcinoma (HCC) was 66.7% in group A (6/9 cases, P = 0.01 vs. group B) and 15.8% (3/19) in group B. According to multivariate analysis, five factors - 50 years or older, low albumin level (<4.0 g/L), abnormal AST level, history of smoking, and absence of alcohol consumption - were associated with death. The adjusted odds ratios for these five factors were 20.65, 10.79, 2.58, 2.24 and 2.08, respectively, and each was statistically significant.ConclusionsWe show that the serum albumin level is an independent risk factor for mortality from all causes in the residents of X town and an important prognostic indicator. Improvement of hypoalbuminaemia should be considered for improvement of prognosis.
European Journal of Internal Medicine | 2000
Yumiko Nagao; Michio Sata; Masayoshi Kage; Tadamitsu Kameyama; Takato Ueno
Background: In recent years, it has been suggested that oral lichen planus (OLP), a chronic inflammatory keratotic lesion, is related to hepatitis C virus (HCV) infection. Therefore, we evaluated whether the presence or absence of HCV infection caused any histopathological differences in OLP tissues. Methods; The subjects consisted of 31 patients with HCV-related liver disease complicated by OLP (32 OLP lesions) and ten OLP patients without complications due to either HCV infection or liver disease (control). A histopathological evaluation was performed in these patients. In addition, immunostaining was done on nine OLP tissues infected with HCV and on six OLP tissues without HCV infection in order to evaluate lymphocyte subsets (T cells or B cells) infiltrating into topical regions with OLP. Furthermore, the severity of hepatic fibrosis and inflammation was evaluated in liver tissues obtained by liver biopsy from six patients with HCV-related liver disease to evaluate whether there were any relationships between the severity of hepatic fibrosis or inflammation and OLP tissues. Results: There were no significant differences in the histopathological characteristics specific to OLP or in the ratios of T and B cells among infiltrating lymphocytes regardless of the presence or absence of HCV infection. Moreover, there were no certain relationships between the severity of hepatic fibrosis or inflammation and the severity of lymphocytic infiltration in OLP. Conclusions: HCV infection does not appear to influence the histopathological and immunohistochemical features of OLP.
BMC Gastroenterology | 2012
Yumiko Nagao; Michio Sata
BackgroundThe aims of this study were to assess the prevalence of hepatitis C virus (HCV) infection in Japanese patients with oral lichen planus and identify the impact of amino acid (aa) substitutions in the HCV core region and IFN-sensitivity-determining region (ISDR) of nonstructural protein 5A (NS5A) associated with lichen planus.MethodsIn this retrospective study, 59 patients (group 1-A) with oral lichen planus among 226 consecutive patients who visited our hospital and 85 individuals (group 1-B, controls) with normal oral mucosa were investigated for the presence of liver disease and HCV infection. Risk factors for the presence of oral lichen planus were assessed by logistic regression analysis. We compared aa substitutions in the HCV core region (70 and/or 91) and ISDR of NS5A of 12 patients with oral lichen planus (group 2-A) and 7 patients who did not have oral lichen planus (group 2-B) among patients (high viral loads, genotype 1b) who received interferon (IFN) therapy in group1-A.ResultsThe prevalence of anti-HCV and HCV RNA was 67.80% (40/59) and 59.32% (35/59), respectively, in group 1-A and 31.76% (27/85) and 16.47% (14/85), respectively, in group 1-B. The prevalence of anti-HCV (P < 0.0001) and HCV RNA (P < 0.0001) in group 1-A was significantly higher than those in group 1-B. According to multivariate analysis, three factors - positivity for HCV RNA, low albumin level (< 4.0 g/dL), and history of smoking - were associated with the development of oral lichen planus. The adjusted odds ratios for these three factors were 6.58, 3.53 and 2.58, respectively, and each was statistically significant. No significant differences in viral factors, such as aa substitutions in the core region and ISDR of NS5A, were detected between the two groups (groups 2-A and -B).ConclusionWe observed a high prevalence of HCV infection in patients with oral lichen planus. Longstanding HCV infection, hypoalbuminemia, and smoking were significant risk factors for the presence of oral lichen planus in patients. It is advisable for Japanese patients with lichen planus to be tested for HCV infection during medical examination.
Virology Journal | 2011
Yumiko Nagao; Michio Sata
BackgroundOral lichen planus (OLP) decreases the quality of life because it can cause spontaneous pain during eating and tooth-brushing and an uncomfortable feeling in the mouth. In addition, OLP may be associated with HCV-related liver disease.We investigated the visual analogue scale (VAS) and effects of oral care gel, REFRECARE-H®, on patients with OLP associated with HCV infection.ResultsNine OLP patients (mean age 67.9 ± 7.6 years) with HCV-related liver diseases were recruited and their VAS score determined along with a biochemical examination of the blood. Types of OLP included erosive (6 patients) and reticular (3). REFRECARE-H®, an oral care gel (therapeutic dentifrice) containing hinokitiol, was applied by each patient as a thin layer on the oral membrane, after each meal and at bedtime for 30 days. Application of REFRECARE-H® improved the quality of life in all terms of dry mouth, breath odor, oral freshness, oral pain during rest, oral pain at a mealtimes, taste disorder, loss of appetite, sleep disorder, depressive mood and jitteriness. VAS scores of dry mouth, breath odor, oral freshness, and sleep disorder were significantly increased 30 days after application of REFRECARE-H® (P = 0.01, P = 0.05, P = 0.03, P = 0.04). VAS scores of oral pain at a mealtimes and taste disorder were increased 30 days after application of REFRECARE-H® (P = 0.06). There was an absence of side effects.ConclusionsREFRECARE-H® improved the quality of life for OLP. It is necessary for the hepatologist to educate patients regarding oral hygiene, as well as provide treatment of liver disease.