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Dive into the research topics where Hiroaki Yamagami is active.

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Featured researches published by Hiroaki Yamagami.


Intervirology | 2008

Influence of occult hepatitis B virus coinfection on the incidence of fibrosis and hepatocellular carcinoma in chronic hepatitis C.

Shunichi Matsuoka; Kazushige Nirei; Akinori Tamura; Hitomi Nakamura; Hiroshi Matsumura; Shuu Oshiro; Yasuo Arakawa; Hiroaki Yamagami; Naohide Tanaka; Mitsuhiko Moriyama

We examined prospectively the influence of occult hepatitis B virus (HBV) infection on the histopathological features and clinical outcome of HCV RNA-positive chronic hepatitis (CH-C) and detected hepatitis B core (HBc) particles in hepatocytes. The subjects were 468 patients with CH-C or liver cirrhosis (LC) who were negative for serum hepatitis B surface antigen (HBsAg) by enzyme-linked immunosorbent assay. HBV DNA was detected in serum by nested PCR. HBsAg and HBc antigen (HBcAg) in liver were investigated using immunohistochemical techniques and light (LM) and electron microscopy (EM). Serum HBV DNA was detected in 43.6% of the patients studied. There were no significant differences between HBV DNA-positive and DNA-negative patients in terms of their clinical profiles. For HBV DNA-positive patients, the degree of inflammatory cell infiltration and irregular regeneration of hepatocytes was significantly greater than for HBV DNA-negative patients. The cumulative probability of development of hepatocellular carcinoma (HCC) was significantly higher for HBV DNA-positive patients than for HBV DNA-negative patients. HBV DNA positivity was a risk factor for the occurrence of HCC according to multivariate analysis. HBsAg and HBcAg were detected in 8.5 and 72.3%, respectively, of the livers of serum HBV DNA-positive individuals. Core particles were detected in the nuclei of the hepatocytes by IEM. The histopathological features and long-term outcome of CH-C or LC could be affected by occult HBV infection.


Intervirology | 2001

Detection of Serum and Intrahepatic Human Hepatocyte Growth Factor in Patients with Type C Liver Diseases

Hiroaki Yamagami; Mitsuhiko Moriyama; Naohide Tanaka; Yasuyuki Arakawa

We determined hepatocyte growth factor (HGF) levels in the serum and liver of patients with hepatitis C and assessed the relationship to histological findings of the liver and hepatitis C virus-related markers in the serum in patients with type C liver diseases. The subjects were 108 patients with chronic hepatitis C (CH), 70 patients with liver cirrhosis C (LC), 38 patients with hepatocellular carcinoma (HCC) and 20 patients with acute hepatitis (AH). As normal controls 20 subjects were studied. The serum HGF levels were measured using an enzyme-linked immunosorbent assay kit. Intrahepatic HGF was investigated by immunoperoxidase staining using monoclonal HGF antibody. The serum HGF level was highest in patients with AH. The serum HGF levels tended to be higher in patients with LC and HCC than those with CH. Further, the serum HGF level was related to the degree of intrahepatic inflammatory cell infiltration and fibrosis, and intrahepatic HGF was noted primarily in the cell membrane of mesenchymal cells in focal necrosis. The degree of intrahepatic HGF expression tended to be higher in patients with high serum HGF levels. In patients with HCC, however, HGF showed little localization in cancer cells, but was noted in infiltrating mesenchymal cells in both cancerous and noncancerous regions. In conclusion, the measurement of serum HGF levels may be useful for estimating the degree of intrahepatic inflammatory reaction and fibrosis. Although further study is necessary, the high serum level of HGF revealed high carcinogenic states in chronic hepatitis and liver cirrhosis type C.


Intervirology | 2003

Long-term outcome, with monitoring of platelet counts, in patients with chronic hepatitis C and liver cirrhosis after interferon therapy

Mitsuhiko Moriyama; Hiroshi Matsumura; Hiroshi Aoki; Toshihiro Shimizu; Kazuhiko Nakai; Takahide Saito; Hiroaki Yamagami; Atsuo Shioda; Miki Kaneko; Iori Goto; Naohide Tanaka; Yasuyuki Arakawa

Objective: Because the determination of the stage of fibrosis depends on rather subjective judgment, more objective parameters are needed. In this study, we followed the long-term outcome, with monitoring of platelet counts, in patients with chronic hepatitis C or liver cirrhosis (LC) who had undergone interferon (IFN) therapy. Methods: 596 patients who were diagnosed at our institute from 1987 to 1998 with chronic hepatitis C and LC were treated with IFNs. A further 58 patients were not treated (NT). The annual rate of changes in platelet counts were calculated and compared for IFN-treated and NT patients. Results: The relationship between the efficacy of IFN therapy and the incidence of hepatocellular carcinoma (HCC) showed that the patients who were virologic sustained responders (VSR) had a significantly lower incidence of HCC than the nonresponders (NR) and NT patients. The change in platelet counts was +4,350/µl/year in the VSR, +1,010/µl/year in the biochemical sustained responders (BSR), –4,540/µl/year in the NR and –6,180/µl/year in the NT patients, indicating a significant platelet increase in the VSR, a decrease of the same magnitude in the NR and NT patients, and no change in the BSR. The cumulative probability of developing HCC and liver failure was significantly higher in groups with decreased platelet counts than in groups with increased platelet counts among patients who had undergone IFN therapy. Multivariate analyses revealed that a decrease in platelet counts was the cardinal risk factor for development of HCC and liver failure in chronic hepatitis C or LC patients. Conclusion: Investigation of platelet counts was useful for determining the long-term outcome of patients who had undergone IFN therapy and for predicting the development of HCC.


Liver International | 2005

Decreased risk of hepatocellular carcinoma in patients with chronic hepatitis C whose serum alanine aminotransferase levels became less than twice the upper limit of normal following interferon therapy

Mitsuhiko Moriyama; Hiroshi Matsumura; Hiroshi Aoki; Toshihiro Shimizu; Hiroaki Yamagami; Atsuo Shioda; Miki Kaneko; Iori Goto; Naohide Tanaka; Yasuyuki Arakawa

Abstract: Aim: The incidence of hepatocellular carcinoma (HCC) in C‐viral chronic hepatitis (CH) and liver cirrhosis (LC) patients after interferon (IFN) therapy was evaluated according to alanine aminotransferase (ALT) levels.


Digestive Diseases and Sciences | 2006

Clinical Significance of Evaluation of Serum Zinc Concentrations in C-Viral Chronic Liver Disease

Mitsuhiko Moriyama; Hiroshi Matsumura; Akiko Fukushima; Kenji Ohkido; Yasuo Arakawa; Kazushige Nirei; Hiroaki Yamagami; Miki Kaneko; Naohide Tanaka; Yasuyuki Arakawa

We evaluated zinc concentrations in patients with hepatitis C virus (HCV)-positive chronic liver disease and correlated them with the clinical profiles of the patients. A total of 100 patients with chronic hepatitis (CH), 29 with liver cirrhosis (LC), and 6 who were asymptomatic HCV carriers (ASC) were examined. All of the patients were positive for serum HCV RNA. One hundred eighteen HCV antibody-positive hepatocellear carcinoma (HCC) patients and 11 healthy subjects also were included in this study. Serum zinc concentrations were evaluated using conventional atomic absorption spectrometry. The median concentration of zinc in patients with CH was statistically lower than that in healthy control subjects. The median zinc concentrations of the LC and HCC groups were significantly lower than that of the CH group. A significant correlation was observed between the zinc concentrations and the platelet counts and albumin concentrations. The zinc concentrations did not correlate with tumor size and number and decreased with the development of Child-Pugh stage. The cumulative survival rate after therapy for HCC nodules in the low zinc concentration group was significantly lower than in the high group. We conclude that the serum concentration of zinc influences the clinical profiles in patients with C-viral chronic liver disease.


Intervirology | 2003

Analysis of background factors and evaluation of a population at high risk of hepatocellular carcinoma.

Kouji Miyazawa; Mitsuhiko Moriyama; Morio Mikuni; Hiroshi Matsumura; Hiroshi Aoki; Toshihiro Shimizu; Hiroaki Yamagami; Miki Kaneko; Atsuo Shioda; Naohide Tanaka; Yasuyuki Arakawa

Objective: We investigated the background clinical factors of patients with hepatocellular carcinoma (HCC) diagnosed at our institute and, from these results, determined those factors important for evaluation of a population at high risk of HCC. Methods: This study comprised 250 patients diagnosed with HCC from 1990 through 1995 in the Nihon University Itabashi Hospital. Background clinical factors, such as the results of blood chemistry at the time of the first angiography, were examined. Results: Markers of viral hepatitis in the 250 cases were as follows: type B (B-HCC), 29 (11.6%), type C (C-HCC), 201 (80.4%); type B+C, 3 (1.2%), and non-B, non-C (NBNC-HCC), 17 (6.8%). Approximately 35% of B-HCC and NBNC-HCC cases, but only 6% of C-HCC cases, exhibited platelet counts (PLT) equal to or more than 200,000/ml. On the other hand, 56.5% of the C-HCC cases exhibited PLT less than 100,000/ml, in contrast to less than 30% of the B-HCC and NBNC-HCC cases. Irrespective of the etiology of HCC, male sex and a history of smoking were characteristic risk factors. The percentages of abnormal results in combinations of tests in the B-HCC, C-HCC and NBNC-HCC subsets were: 69, 97 and 70% in the aspartate aminotransferase (AST) + PLT group (group A); 83, 98 and 70% in the group A + alanine aminotransferase (ALT) group (group B), and 86, 98 and 100% in the group B + γ-glutamyl transpeptidase (γ-GTP) group (group C), respectively. When hepatitis B surface antigen (HBsAg) and hepatitis C antibody (HCV-Ab) were also taken into account, abnormal results were found in every case in all of the HCC groups. Conclusion: C-HCC was found predominantly in cases with liver cirrhosis, whereas B-HCC and NBNC-HCC were observed more frequently in cases without liver cirrhosis. Testing for HBsAg and HCV-Ab, in addition to AST, ALT, PLT and γ-GTP, is considered necessary when screening for HCC.


Journal of Dermatology | 1991

A Case of Cutaneous Metastases of Gastric Carcinoma Showing Peculiar Clinical Features

Mitsuo Miyashita; Michio Honjo; Hiroyuki Suzuki; Hiroaki Yamagami; Atsuo Shioda; Yasuyuki Arakawa; Yutaka Matsuo

A 52‐year‐old male patient presented with multiple cutaneous nodules on the face, trunk, and upper extremities. Examination of a skin biopsy specimen disclosed numerous signet ring cells throughout the dermis. Histopathologic examination of the stomach, along with gastroscopy, revealed that the cutaneous metastases were of gastric origin.


Journal of Clinical Biochemistry and Nutrition | 2012

Zinc supplementation therapy improves the outcome of patients with chronic hepatitis C.

Hiroshi Matsumura; Kazushige Nirei; Hitomi Nakamura; Yasuo Arakawa; Teruhisa Higuchi; Jyunpei Hayashi; Hiroaki Yamagami; Syunichi Matsuoka; Masahiro Ogawa; Noriko Nakajima; Naohide Tanaka; Mitsuhiko Moriyama

We administered zinc supplementation therapy over three years to patients with chronic hepatitis C and reported and that the aspartate aminotransferase (AST) and alanine aminotaransferase (ALT) levels decreased, and platelet counts increased, significantly in the group with increased serum zinc concentrations. We are continuing this treatment to clarify the long-term consequences and report here the changes in serum zinc concentrations over seven years and compare the cumulative incidence of hepatocellular carcinoma (HCC). We administered polaprezinc to 32 patients, randomly selected for zinc therapy (treatment group), while another 30 formed the control group. We measured the serum zinc and albumin concentrations and conducted a prospective study to determine long-term outcomes. The changes and rates of change of serum zinc concentrations after seven years were 76.7 ± 18.2 µg/dl and +0.302 ± 0.30% in the treatment group and 56.7 ± 12.4 µg/dl and +0.033 ± 0.21% in the control group and had increased significantly (p = 0.0002, p = 0.0036). Progression of liver disease seemed to vary, depending on serum albumin concentrations. In the group with baseline serum albumin concentrations of 4.0 g/dl or more, the change and rate of change of serum zinc concentrations increased significantly, and the cumulative incidence of HCC tended to decrease, in the treated group. According to multivariate analysis, the factors that contribute to a reduction in the incidence of HCC are zinc therapy (risk ratio: 0.113, 95% CI: 0.015–0.870, p = 0.0362), and platelet counts (0.766, 0.594–0.989, 0.0409). Zinc supplementation therapy seems to improve liver pathology and reduce the incidence of HCC.


Intervirology | 2006

Measurement of human intercellular adhesion molecule 1 in the blood is useful for predicting the occurrence of hepatocellular carcinomas from chronic hepatitis C and liver cirrhosis.

Mitsuhiko Moriyama; Hiroshi Matsumura; Jiro Shioda; Hiroshi Aoki; Hitomi Nakamura; Yasuo Arakawa; Kazushige Nirei; Hiroaki Yamagami; Miki Kaneko; Naohide Tanaka; Yasuyuki Arakawa

Objective: We measured the concentrations of serum intercellular adhesion molecule 1 (sICAM-1) in patients with C-viral chronic liver diseases and started prospective studies immediately thereafter, in order to determine whether the concentration of sICAM-1 is useful for predicting the occurrence of hepatocellular carcinoma (HCC) following C-viral chronic hepatitis (CH) and liver cirrhosis (LC). Methods: We studied 74 patients with CH, 18 with LC, and 28 patients with HCC who visited our institute from 1993 through 1996. All were positive for hepatitis C virus RNA in the blood. The concentrations of sICAM-1 were measured using enzyme-linked immunosorbent assay kits. The expression of ICAM-1 in the liver was detected by indirect immunoperoxidase staining. Results: The concentrations of sICAM-1 were significantly higher in patients with LC and HCC than in patients with CH. The sICAM-1 concentrations were high in patients whose platelet counts were low. ICAM-1 in the liver was localized to the endoplasmic reticulum or the membrane of cancer cells. The cumulative rate of occurrence of HCC from CH or LC was significantly higher in the high-sICAM-1 group (>400 ng/ml) than in the low-sICAM-1 group. Multivariate analysis revealed that elevation of the sICAM-1 concentration is a significant risk factor for the occurrence of HCC. Conclusion: Evaluation of the sICAM-1 concentration is useful for prediction of the occurrence of HCC in patients with C-viral CH or LC.


Case Reports in Gastroenterology | 2013

Spontaneous Regression of Polyposis following Abdominal Colectomy and Helicobacter pylori Eradication for Cronkhite-Canada Syndrome

Kimitoshi Kato; Yukimoto Ishii; Takerou Mazaki; Toshiki Uehara; Hitomoi Nakamura; Hiroshi Kikuchi; Hiroaki Yamagami; Hideki Sato; Shigeaki Mizuno; Masayoshi Soma; Akihiro Henmi; Hideki Masuda; Mitsuhiko Moriyama; Masanori Tanaka

The etiology of Cronkhite-Canada syndrome (CCS) remains unknown and many cases are refractory to treatment. Therefore, new therapies are urgently needed. Furthermore, a number of CCS cases with gastrointestinal carcinoma have been reported. Our patient had rapid onset of CCS and early development of colon carcinoma associated with adenomas. High anterior resection of the sigmoid colon and ileostomy were performed, and her symptoms and endoscopic and histological findings improved. Helicobacter pylori eradication was carried out 2 years later, surgical closure of an ileal fistula the following year. After 4 months, upper gastrointestinal endoscopy and colonoscopy showed that the CCS lesions had completely disappeared, and biopsies confirmed a normal stomach, duodenum, ileum and colon histologically. The patient has maintained remission for 2 years. The clinical course of this case, showing complete regression of CCS lesions following abdominal colectomy and H. pylori eradication, suggests the significance of H. pylori infection in the treatment of CCS.

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