Mitsugi Yasuda

Mutations in a hydrophilic part of the core gene of hepatitis C virus in patients with hepatocellular carcinoma in China

We investigated the association between hepatocellular carcinoma (HCC) and the genomic characteristics of the hepatitis C virus (HCV) isolated from residents of the inshore region of the Yangtze River, an area that has one of the highest incidence of HCC in China. We determined the genomic heterogeneity of HCV, and the sequence divergence of the HCV core gene in individuals with chronic hepatitis and HCC. HCV genotype II was predominant among these isolates, which were homologous to other Chinese and Japanese HCV isolates. The rate of nucleotide substitutions in the core gene was significantly greater for isolates from HCC patients than for those from individuals with chronic hepatitis. The nucleotide substitutions were unevenly scattered along the core gene; a cluster of missense mutations was apparent in the region encoding the second hydrophilic domain of the core protein. The rate of occurrence of missense mutations per nucleotide substitution was significantly greater in this clustering variable region (CVR) of the core gene than in the remaining core gene sequence. These observations suggest that mutations in the CVR may be involved in the pathogenesis of chronic HCV infection during hepatocellular carcinogenesis.

Prevalence and characteristics of nodular gastritis in Japanese elderly

Nodular gastritis (NG) is defined as antral gastritis with endoscopic findings usually characterized by a miliary pattern resembling “goose flesh.” There is a possible association between NG and gastric cancer. The aim of our study is to investigate whether there are some differences between young and elderly people in incidence and characteristics of NG and estimate potential risk factors for gastric cancer in adults with NG.

EXAMINATION OF RESPIRATORY AND CIRCULATORY DYNAMICS DURING EXAMINATION USING A THIN GASTROINTESTINAL ENDOSCOPE IN ADVANCED-AGE SUBJECTS

Background:  Endoscopic examination influences cardiovascular hemodynamics. Upper gastrointestinal examinations are currently performed with a thin endoscope. In the present study, respiratory and circulatory dynamics and autonomic nervous activity using a thin endoscope (XP260) or a standard endoscope (XQ240) were investigated.

Usefulness and Limitations of Endoscopic Ultrasonography in Diagnosis of Adenomyomatosis of the Gallbladder

Abstract: Although endoscopic ultrasonography (EUS) is commonly used to examine lesions in the gallbladder, its ability to accurately diagnose adenomyomatosis (ADM) has not been evaluated. We compared the accuracy of EUS and various other imaging techniques in the diagnosis of ADM. Thirty‐one patients undergoing cholecystectomy after elevated lesions were found in the gallbladder by various imaging techniques were studied retrospectively. Based on histopathologic examination, the sensitivity and specificity of EUS were evaluated in ADM. The sensitivity of abdominal ultrasonography, CT and ERCP in ADM were also evaluated. Of the 11 patients diagnosed with ADM by EUS, 9 cases were confirmed histologically (81.8%). Of the 11 patients with histologic diagnosis of ADM, 9 were accurately diagnosed preoperatively by EUS (81.8%). EUS proved more reliable for diagnosis of ADM than the other imaging techniques. Important diagnostic features include preservation of the three‐layered structure of the gallbladder, wall‐thickening exceeding 3 mm, and 2 or more Rokitansky‐Aschoff sinuses occurring within a 1 cm area of the gallbladder.