Hiroyasu Nagahama
Kumamoto University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Hiroyasu Nagahama.
Biochemical and Biophysical Research Communications | 2010
Omar F. Dessouki; Yasuyuki Kamiya; Hiroyasu Nagahama; Motohiko Tanaka; Shinya Suzu; Yutaka Sasaki; Seiji Okada
Impaired activity of NK (natural killer) cells has been proposed as a mechanism contributing to viral persistence and chronic infection in hepatitis C (HCV) infection. We aimed to assess the impact of HCV infection on NK cells regarding frequency, subset distribution, and cytotoxic and cytokine secretion functions, as well as IFN-alpha and ribavirin therapeutic effects on NK cells. Significant reduction of total NK frequency and the CD56(dim)16(+) subset was observed in chronic HCV patients. IFN-gamma expression upon stimulation with K562 was severely suppressed but cytotoxicity measured by CD107a expression was maintained. These adverse effects were reversed after treatment with pegylated IFN-alpha and ribavirin; however, these skewed functions were not recovered in treatment-resistant patients. Thus, HCV chronic infection severely affects NK functions, except for cytotoxicity. Altered NK cell frequency and cytokine secretion by HCV infection may contribute to impaired cellular immune response and virus persistence.
Oncology | 1998
Takuji Okusaka; Shuichi Okada; Hiroshi Ishii; Masafumi Ikeda; Hidekazu Nakasuka; Hiroyasu Nagahama; Ryoko Iwata; Hiroyoshi Furukawa; Kenichi Takayasu; Yukihiro Nakanishi; Michiie Sakamoto; Setsuo Hirohashi; Masayoshi Yoshimori
Zinostatin stimalamer (SMANCS) is a lipophilic intra-arterial chemotherapeutic agent for hepatocellular carcinoma (HCC). Thirty HCC patients underwent transcatheter arterial injection of 4 mg SMANCS-lipiodol emulsion. Their responses were evaluated by computed tomography 1 month after treatment. Complete response (CR) was defined as disappearance or 100% necrosis of all tumors. Partial response (PR) was defined as ≧50% reduction and/or ≧50% necrosis. We regarded the lipiodol accumulation in tumors as being necrotic. CR and PR were observed in 8 patients (27%) and 4 patients (13%), respectively, and the overall response rate (CR + PR/all patients) was 40% (12/30). Of 12 patients whose serum α-fetoprotein levels had been more than 200 ng/ml before treatment, 5 patients (42%) showed more than 50% reduction in this level within 1 month after treatment. Toxicity was quite acceptable, although grade 4 toxicity (WHO) was observed as liver dysfunction in 1 patient. Transarterial chemotherapy with SMANCS, which is well tolerated, appears to have moderate antitumor effect in patients with HCC.
Case Reports in Gastroenterology | 2011
Hideaki Naoe; Eisuke Kaku; Yumi Ido; Rika Gushima; Yoko Maki; Hirokazu Saito; Seiichiro Yokote; Ryosuke Gushima; Kouichi Nonaka; Yohmei Hoshida; Tetsuya Murao; Tetsu Ozaki; Kazunori Yokomine; Hideki Tanaka; Hiroyasu Nagahama; Kouichi Sakurai; Motohiko Tanaka; Ken Ichi Iyama; Hideo Baba; Yutaka Sasaki
Metastasis of gastrointestinal stromal tumor (GIST) into the central nervous system is extremely rare. We report a patient with synchronous GIST and brain metastasis. At disease onset, there was left hemiplegia and ptosis of the right eyelids. Resection cytology of the brain tumor was reported as metastasis of GIST. After positron emission tomography examination, another tumor in the small bowel was discovered, which suggested a small bowel GIST associated with intracranial metastasis. Immunohistochemical analysis of the intestinal tumor specimen obtained by double balloon endoscopy showed a pattern similar to the brain tumor, with the tumors subsequently identified as intracranial metastases of jejunal GIST. After surgical resection of one brain tumor, the patient underwent whole brain radiation therapy followed by treatment with imatinib mesylate (Gleevec; Novartis Pharma, Basel, Switzerland). Mutational analysis of the original intestinal tumor revealed there were no gene alterations in KIT or PDGFRα. Since the results indicated the treatment had no apparent effect on either of the tumors, and because ileus developed due to an intestinal primary tumor, the patient underwent surgical resection of the intestinal lesion. However, the patient’s condition gradually worsen and she subsequently died 4 months after the initial treatment.
International Journal of Clinical Oncology | 1998
Takuji Okusaka; Shuichi Okada; Hiroshi Ishii; Hidekazu Nakasuka; Hiroyasu Nagahama; Masayoshi Yoshimori; Minako Sumi; Kouichi Tokuuye; Yoshikazu Kagami; Hiroshi Ikeda
BackgroundPancreatic cancer is a highly virulent disease with a poor prognosis. Although objective tumor response to chemotherapy and/or radiotherapy is low, some patients show an improvement in their symptoms after treatments, without obvious tumor regression.MethodsWe assessed the clinical benefit of concurrent chemoradiotherapy with protracted 5-fluorouracil infusion in patients with locally advanced pancreatic cancer. Sixteen patients were enrolled in this study. The clinical benefit response to the chemoradiotherapy was evaluated by 2 indicators, including pain (intensity of pain and consumption of morphine) and performance status. A patient was defined to be a clinical benefit responder if 1 of these 2 variables was positive, and the other variable was positive or stable.ResultsSeven patients (44%) responded. Six patients (38%) were classified as stable, and 3 (19%) as nonresponders. The survival period in responders was significantly longer than that in nonresponders and stable patients.ConclusionConcurrent external-beam radiation therapy, with protracted 5-fluorouracil infusion, may be a meaningful treatment for locally advanced pancreatic cancer.
Hepato-gastroenterology | 1997
Takuji Okusaka; Shuichi Okada; Hiroshi Ishii; Haruhiko Nose; Hiroyasu Nagahama; Hidekazu Nakasuka; Ikeda K; Masayoshi Yoshimori
Journal of Gastroenterology | 2011
Masakuni Tateyama; Hiroshi Yatsuhashi; Naota Taura; Yasuhide Motoyoshi; Shinya Nagaoka; Kenji Yanagi; Seigo Abiru; Koji Yano; Atsumasa Komori; Kiyoshi Migita; Minoru Nakamura; Hiroyasu Nagahama; Yutaka Sasaki; Yuzo Miyakawa; Hiromi Ishibashi
Journal of Gastroenterology | 2010
Masafumi Ikeda; Seishi Maeda; Hiroshi Ashihara; Hiroyasu Nagahama; Motohiko Tanaka; Yutaka Sasaki
Japanese Journal of Clinical Oncology | 1997
Hiroyasu Nagahama; Shuichi Okada; Takuji Okusaka; Hiroshi Ishii; Masafumi Ikeda; Hidekazu Nakasuka; Masayoshi Yoshimori
Hepato-gastroenterology | 1996
Hiroshi Ishii; Shuichi Okada; Haruhiko Nose; Takuji Okusaka; Hiroyasu Nagahama; Hidetsugu Nakayama; Hidekazu Nakasuka; Masayoshi Yoshimori
Hepato-gastroenterology | 1996
Takuji Okusaka; Shuichi Okada; Haruhiko Nose; Hiroshi Ishii; Hidekazu Nakasuka; Hidetsugu Nakayama; Hiroyasu Nagahama; Masayoshi Yoshimori; Kazuaki Shimada; Junji Yamamoto; Tadatoshi Takayama; Tomoo Kosuge; Susumu Yamasaki; Michiie Sakamoto; Setsuo Hirohashi