Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by T Hamaguchi
Total Records ( 4 ) for T Hamaguchi
  I Nozaki , T Hamaguchi , N Sanjo , M Noguchi Shinohara , K Sakai , Y Nakamura , T Sato , T Kitamoto , H Mizusawa , F Moriwaka , Y Shiga , Y Kuroiwa , M Nishizawa , S Kuzuhara , T Inuzuka , M Takeda , S Kuroda , K Abe , H Murai , S Murayama , J Tateishi , I Takumi , S Shirabe , M Harada , A Sadakane and M. Yamada
 

We analysed the epidemiological data and clinical features of patients with prion diseases that had been registered by the Creutzfeldt-Jakob Disease Surveillance Committee, Japan, over the past 10 years, since 1999. We obtained information on 1685 Japanese patients suspected as having prion diseases and judged that 1222 patients had prion diseases, consisting of definite (n = 180, 14.7%) and probable (n = 1029, 84.2%) cases, except for dura mater graft-associated Creutzfeldt–Jakob disease which also included possible cases (n = 13, 1.1%). They were classified into 922 (75.5%) with sporadic Creutzfeldt–Jakob disease, 216 (17.7%) with genetic prion diseases, 81 (6.6%) with acquired prion diseases, including 80 cases of dura mater graft-associated Creutzfeldt–Jakob disease and one case of variant Creutzfeldt–Jakob disease, and three cases of unclassified Creutzfeldt–Jakob disease (0.2%). The annual incidence rate of prion disease ranged from 0.65 in 1999 to 1.10 in 2006, with an average of 0.85, similar to European countries. Although methionine homozygosity at codon 129 polymorphism of the prion protein gene was reported to be very common (93%) in the general Japanese population, sporadic Creutzfeldt–Jakob disease in Japan was significantly associated with codon 129 homozygosity (97.5%), as reported in western countries. In sporadic Creutzfeldt–Jakob disease, MM1 type (Parchi’s classification) is the most common, as in western countries. Among atypical sporadic Creutzfeldt–Jakob disease cases, the MM2 type appeared most common, probably related to the very high proportion of methionine allele in the Japanese population. As for iatrogenic Creutzfeldt–Jakob disease, only dura mater graft-associated Creutzfeldt–Jakob disease cases were reported in Japan and, combined with the data from previous surveillance systems, the total number of dura mater graft-associated Creutzfeldt–Jakob disease was 138, comprising the majority of worldwide dura mater graft-associated Creutzfeldt–Jakob disease patients. Regarding genetic prion diseases, the most common mutation of prion protein gene was V180I (41.2%), followed by P102L (18.1%), E200K (17.1%) and M232R (15.3%), and this distribution was quite different from that in Europe. In particular, V180I and M232R were quite rare mutations worldwide. Patients with V180I or M232R mutations rarely had a family history of prion diseases, indicating that a genetic test for sporadic cases is necessary to distinguish these from sporadic Creutzfeldt–Jakob disease. In conclusion, our prospective 10-year surveillance revealed a frequent occurrence of dura mater graft-associated Creutzfeldt–Jakob disease, and unique phenotypes of sporadic Creutzfeldt–Jakob disease and genetic prion diseases related to the characteristic distribution of prion protein gene mutations and polymorphisms in Japan, compared with those in western countries.

  T Hamaguchi , T Ito , Y Inoue , T Limpaseni , P Pongsawasdi and K. Ito
 

Endo-β-N-acetylglucosaminidases are thought to be key enzymes in the catabolism of asparagine-linked oligosaccharides. However, little is known about the enzymes of this type in basidiomycetes. We investigated endo-β-N-acetylglucosaminidases in basidiomycetes using fluorescence-labeled glycoasparagines as substrates. Flammulina velutipes showed high activity and its enzyme was named endo-β-N-acetylglucosaminidase FV (Endo FV). The enzyme purified from the fruiting bodies of F. velutipes was separated into two forms. Endo FV was specific for high mannose and hybrid-type oligosaccharides. The enzyme was remarkably less active against asparagine-linked oligosaccharides attached to glycoproteins. It transferred an asparagine-linked oligosaccharide to Glc, but not to Gal. cDNA of Endo FV was cloned. It was composed of a 996-bp open reading frame encoding 331 amino acid residues. A recombinant Endo FV expressed in Escherichia coli showed enzymatic activity. The Endo FV gene in the genome of F. velutipes had no introns. The gene encoding Endo FV showed little homology with genes of known endo-β-N-acetylglucosaminidases. A chitinase active site motif existed in the deduced primary structure, indicating that Endo FV belongs to glycoside hydrolase family 18. The deduced amino acid sequence of Endo FV had regions conserved in class III chitinases from fungi though it showed little homology with the sequence of any other endo-β-N-acetylglucosaminidases. A folding model of Endo FV indicated it to be homologous with the tertiary structure of Endo H which is quite similar in specificity for asparagine-linked oligosaccharides. This study suggests that Endo FV may become similar to Endo H in substrate specificity as a result of evolutionary convergence.

  N. T Okita , Y Yamada , D Takahari , Y Hirashima , J Matsubara , K Kato , T Hamaguchi , K Shirao , Y Shimada , H Taniguchi and T. Shimoda
  Objective

Vascular endothelial growth factor (VEGF) and its receptors VEGF-R1, -R2 and -R3 play important roles in tumor angiogenesis and are associated with poor prognosis in several solid tumors. However, their functional significance remains unclarified. Here, we investigated the associations between the expression of these receptors and the clinical outcomes of colorectal cancer (CRC) patients.

Methods

An immunohistochemical approach was used to detect VEGF-R1, -R2 and -R3 expression in 91 CRC patients who underwent surgery and received chemotherapy at the National Cancer Center Hospital. Statistical analysis was performed to determine the prognostic significance of these biomarkers.

Results

Immunoreactivity for VEGF-R2 and -R3 was localized in microvessels and that for VEGF-R1 in cancer cells and stromal microvessels. VEGF-R1 staining in cancer cells (>10% staining) was found in 84 patients (92%) and in stromal vessels in 75 patients (82%). VEGF-R2 staining in tumor vessels (>10% staining) was found in 84 patients (92%), whereas VEGF-R3 staining was found in 85 patients (93%). Strong positive staining (>60% staining) of VEGF-R1 in tumor cells, and VEGF-R1, -R2 and -R3 in vessels was identified in 58 (64%), 33 (36%), 52 (57%) and 60 (66%) patients, respectively. Univariate analysis revealed that VEGF-R1 strong positive staining correlated with shorter post-operative survival in patients with Stage II/III disease (P = 0.01), but neither VEGF-R2 nor R3 expression correlated with survival.

Conclusions

VEGF-R1, -R2 and -R3 were highly expressed in CRC cells and stromal vessels. VEGF-R1 strong positive staining correlated with shorter survival after CRC surgery.

  C Tanai , T Hamaguchi , S. i Watanabe , H Katai , N Tochigi and Y. Shimada
 

We describe a 60-year-old male patient who survived for a long period after pulmonary metastasectomy for gastric cancer. The patient initially underwent distal gastrectomy for gastric cancer. Seventeen months after the gastrectomy, surgical resection of solitary pulmonary metastasis was performed and following resection, the patient has survived without relapse for more than 5 years. Carefully selected patients have a good chance of benefiting from pulmonary metastasectomy for gastric cancer.

 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility