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Featured researches published by Hirohumi Munakata.


Cancer | 1987

Type 1a glycogen storage disease with hepatoblastoma in siblings.

Etsuro Ito; Yuichi Sato; Kyoichi Kawauchi; Hirohumi Munakata; Yosimasa Kamata; Hirahu Yodono; Masaru Yokoyama

Clinical and histologic details of the two siblings with type 1a glycogen storage disease (GSD‐1a) who developed hepatoblastoma are presented. The light microscopic studies on hepatic tumor in both siblings revealed fetal type of hepatoblastoma. Ultrastructural findings in Patient 2 showed markedly altered mitochondria, which were frequently surrounded by the rough endoplasmic reticulum. This is the first known occurrence with this association, and the third report on the familial occurrence of this neoplasm. Glycogen storage disease may increase the risk of hepatocellular carcinoma and hepatoblastoma.


Surgery Today | 1993

Survival and recurrence after low anterior resection and abdominoperineal resection for rectal cancer: the results of a long-term study with a review of the literature.

Mitsuru Konn; Takayuki Morita; Ryukichi Hada; Yuji Yamanaka; Mutsuo Sasaki; Hirohumi Munakata; Hidetoshi Suzuki; Shigeaki Inoue; Masaaki Endoh; Yuzuru Sugiyama; Keiichi Ono

Morbidity, survival, and recurrence in 203 patients treated with curative low anterior resection (LAR) were compared with those in 100 patients treated with curative abdominoperineal resection (APR). The overall 5-year survival figures for the total number of, LAR and APR patients were 75.6±5.7%, 79.8±6.4% and 67.7±9.6%, respectively. The prognosis for cancers situated low enough in the rectum to involve the anal canal was poor even when managed by APR, as evidenced by a low survival at 5 years of 59.0±9.6% and a high pelvic recurrence rate of 34%. For all except these tumors, LAR proved at least equal to, or better than APR as a curative surgical method for middle and low rectal cancers, on the basis of 5-year survival being 79.8±6.4% vs 78.7±5.2%, operative mortality being 1.5% vs 1.0%, morbidity being 39.4% vs 59.0%, and the incidence of pelvic recurrence being 8.9% vs 13.5%. When deciding upon the most appropriate surgical procedure for rectal cancer, especially for middle or low rectal lesions, the patient should not simply be condemned to a permanent colostomy. Thus, we first attempt LAR for every lesion except those which are very advanced or those with anal canal involvement, if technically feasible and suitable for the individual patient.


Breast Cancer | 2002

Adenoma of the Nipple in an Adolescent

Michihiro Sugai; Kiyoshi Murata; Norihisa Kimura; Hirohumi Munakata; Ryukichi Hada; Yoshimasa Kamata

We recently treated a 14-year-old girl with a clinically and histologically diagnosed with adenoma of the nipple. Enucleation of a mass preserving the nipple was successfully performed. Adenoma of the nipple is a rare disease which is often mistaken clinically for Paget’s disease. About 200 cases of the tumors have been reported worldwide so far. The most common symptom is erosion of the nipple and nipple discharge. Our case had erosion of the nipple but no discharge. Adenoma of the nipple is a benign lesion which can be successfully treated by a simple surgery.


Cytokine | 2003

Effect of MG132, a proteasome inhibitor, on the expression of growth related oncogene protein-α in human umbilical vein endothelial cells

Takeo Shibata; Tadaatsu Imaizumi; Tomoh Matsumiya; Wakako Tamo; Masaharu Hatakeyama; Hidemi Yoshida; Hirohumi Munakata; Ikuo Fukuda; Kei Satoh

Growth related oncogene protein-alpha (GRO-alpha) is a member of C-X-C chemokine and plays an important role in inflammatory responses. Expression of GRO gene family is regulated by a number of factors at both transcriptional and posttranscriptional levels. In the present study, we have addressed the possible regulation of GRO-alpha expression by ubiquitin-proteasome system. Cultures of human umbilical vein endothelial cells were treated with a proteasome inhibitor, MG132, and the levels of GRO-alpha mRNA were analyzed by reverse transcription-polymerase chain reaction or northern blotting. Levels of GRO-alpha protein in the cell-conditioned medium were determined by enzyme-linked immunosorbent assay. MG132 alone increased the levels of GRO-alpha mRNA and protein; however, it did not affect the GRO-alpha mRNA induced by lipopolysaccharide (LPS) and inhibited the LPS-induced decrease in IkappaB levels. Other proteasome inhibitors, MG115 and lactacystin, also induced the expression of GRO-alpha mRNA. MG132 induced the phosphorylation of p38 MAPK, MEK and JNK. Pretreatment of the cells with SB203580, an inhibitor of p38 MAPK, suppressed the MG132-induced GRO-alpha expression, but pretreatment of the cells with U0126, PD98059 or SP600125, inhibitors of MEK1/2 or JNK, did not influence the effect of MG132. We conclude that MG132 upregulates GRO-alpha expression in vascular endothelial cells, at least in part, through the activation of p38 MAPK.


Transplantation Proceedings | 2008

Timing for Orthotopic Liver Transplantation in Children With Biliary Atresia: A Single-Center Experience

Yoshikazu Toyoki; Kenichi Hakamada; S. Narumi; Masaki Nara; Michihiro Sugai; Hirohumi Munakata; Mutsuo Sasaki

INTRODUCTION Biliary atresia is the most common indication for orthotopic liver transplantation (OLT) in childhood. The purpose of this study was to determine predictive prognostic factors for children with biliary atresia related to the timing for OLT within 15 months after hepatoportoenterostomy (HPE). PATIENTS AND METHODS We retrospectively analyzed the medical records of 25 children (7 boys and 18 girls) who underwent HPE because of biliary atresia between January 1990 and December 2005 at our center. Data examined included age and pathologic findings at HPE, Pediatric End-Stage Liver Disease score at first admission, whether phototherapy was given, liver function test results and total bilirubin level before and 30 days after HPE, and number of cholangitis events. RESULTS Twelve children were alive with their native liver, 8 had undergone living donor OLT (all children alive), and 5 had died without OLT. Five- and 10-year survival rates without OLT after HPE were 47.4% and 26.3%, respectively. At univariate analysis, the predictive prognostic factors for children with biliary atresia were total bilirubin level at 30 days after HPE and Pediatric End-Stage Liver Disease score before HPE. At multivariate analysis, the only prognostic factor was total bilirubin level at 30 days after HPE. CONCLUSIONS In this study, the predictive prognostic factor was total bilirubin level at 30 days after HPE. Orthotopic liver transplantation within 15 months after HPE is needed in children with biliary atresia with a high total bilirubin level at 30 days after HPE.


Pediatric Surgery International | 2006

A case of pancreatoblastoma prenatally diagnosed as intraperitoneal cyst

Michihiro Sugai; Norihisa Kimura; Minoru Umehara; Hirohumi Munakata; Nobuhisa Yajima; Soroku Yagihashi; Gunther Klöppel

Pancreatoblastoma in childhood is a very rare malignant tumor, but is considered to have a relatively good prognosis because of its low metastatic potential. We report 1-day-old female infant who was recently found to have an intraabdominal cyst on prenatal ultrasound examination. The tumor was a unilocular, cystic mass without invasion or metastasis to other organs, allowing total resection. It was diagnosed postnatally with pancreatoblastoma.


Journal of Medical Ultrasonics | 2007

Monitoring of hepatic artery resistance index and optimal timing of liver transplantation for biliary atresia

Michihiro Sugai; Masaaki Endoh; Ryukichi Hada; Hirohumi Munakata

PurposeBiliary atresia (BA) is diagnosed by ultrasound (US) examination of the hepatic artery and gallbladder. This study was designed to assess the usefulness of the hepatic artery resistance index (HRI) measured by Doppler ultrasonography (DUS) for prognostication of liver viability in children with BA.MethodsSeventeen patients with non-correctable BA were examined by US and DUS before and after hepatoenterostomy to evaluate hepatic artery dynamics.ResultsDilatation of the hepatic artery was demonstrated in all 17 patients. US of the gallbladder showed hypogenesis in seven patients. Preoperatively, all 17 BA patients had an HRI of <1.0. Six of the 17 patients underwent liver transplantation. Four of the six had an HRI of >0.9, and the HRI decreased after the procedure. All patients were alive at the time of writing.ConclusionsRegular US examinations are helpful for diagnosis of BA and for detecting patients at high risk. A prospective study is required to determine the optimal frequency of assessment.


Transplantation Proceedings | 2008

Living donor liver transplantation for a child with recurrent pediatric adult-type hepatocellular carcinoma.

Masaki Nara; Yoshikazu Toyoki; Kenichi Hakamada; S. Narumi; Keinosuke Ishido; Michihiro Sugai; Hirohumi Munakata; Etsuro Ito; Mutsuo Sasaki

INTRODUCTION Pediatric hepatocellular carcinoma (HCC) is an uncommon disease with a poor prognosis. There are few reports about liver transplantation for pediatric adult-type HCC. We experienced a case of living donor liver transplantation (LDLT) for a child with recurrent pediatric adult-type HCC. CASE REPORT A 12-year-old boy was admitted to the Department of Pediatrics in our institution due to HCC in May 2005. He underwent hepatectomy after 3 courses of chemotherapy in July 2005. After the operation, he had 2 more courses of the same chemotherapy. His posttheraputic course was uneventful for 1 year. However, his alpha-fetoprotein level increased and a computed tomography (CT) scan showed recurrent tumor in his remnant liver in October 2006. He underwent another chemotherapy session immediately. However, CT revealed multiple liver tumors after chemotherapy in December 2006. His mother requested to be an LDLT donor, which was performed on January 23, 2007. The donor operation was a right hepatic lobectomy. The postoperative course of the donor was unremarkable and she has now returned to work. The recipients posttransplantation course was uneventful and he was discharged at postoperative day 53 and is currently doing well. CONCLUSION Liver transplantation in conjunction with chemotherapy may have an increasing role in the management of pediatric HCC.


Journal of Hepato-biliary-pancreatic Sciences | 2010

Sonographic demonstration of wall thickness of the gallbladder in pediatric patients with pancreatico-biliary maljunction

Michihiro Sugai; Keinosuke Ishido; Masaaki Endoh; Ryukichi Hada; Hirohumi Munakata


Hepato-gastroenterology | 2008

Immunohistochemical study on liver fibrosis in biliary atresia.

Kiyoshi Murata; Yoshimasa Kamata; Hirohumi Munakata; Michihiro Sugai; Mutsuo Sasaki

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