Hiroshi Maekubo

A case of transfusion‐transmitted hepatitis E caused by blood from a donor infected with hepatitis E virus via zoonotic food‐borne route

BACKGROUND: Five cases of transfusion transmission of hepatitis E virus (HEV) have been reported so far. The infection routes of the causative donors remain unclear, however. Also, the progress of virus markers in the entire course of HEV infection has not been well documented.

Full-Length Sequences of Six Hepatitis E Virus Isolates of Genotypes III and IV from Patients with Sporadic Acute or Fulminant Hepatitis in Japan

Objective: Ranges of variation and conservation in sequence need to be defined for detecting and genotyping hepatitis E virus (HEV). Methods: Six HEV isolates from Japanese patients were sequenced over the entire genome and compared phylogenetically along with 16 reported HEV isolates, including two from pigs. Results: Three of the six HEV isolates were of genotype III, and the remaining three were of genotype IV. Local clusterings of Japanese HEV isolates were observed in the phylogenetic analyses, including a swine HEV isolate reported previously (swJ570). All six HEV isolates possessed three open reading frames (ORFs). The ORF3 in the three isolates of genotype III were in a different reading frame, while that in the three isolates of genotype IV were in the same reading frame as ORF1. A stretch of 46–96 nucleotides was identified, point mutations and deletions in which were specific for the four genotypes (I–IV). A polymerase chain reaction method was developed with 9 nested universal primers, deduced from conserved regions in the 5′-terminal sequences of the 22 HEV genomes. Conclusions: Conserved and genotype-specific variation in HEV sequences, identified in the comparison of 22 full-length genomes, would be useful in designing primers for sensitive detection and specific genotyping of HEV RNA.

A case report: two patients with fulminant hepatitis E in Hokkaido, Japan

Hepatitis E virus (HEV) has been listed as one of the major agents that cause fulminant hepatitis in HEV-endemic areas, but not in non-endemic areas. Recently, however, we experienced two cases of fulminant hepatitis E in Hokkaido, Japan: case-1 was a 34-year-old woman and case-2, a 51-year-old man, neither having a history of travelling outside Japan or contact with travellers abroad or foreigners. HEV RNA was detected in their acute-phase serum and sequencing analyses indicated that they were infected with different strains of HEV: genotype III in case-1 and IV in case-2. Case-1 patient deceased after liver transplantation, while case-2 patient survived. Based on these cases, we suggest that HEV should be considered as an aetiologic agent for fulminant hepatitis, even in non-endemic areas.

High sensitivity of a novel ELISA for anti-M2 in primary biliary cirrhosis.

Abstract: The use of an ELISA for the detection of anti-M2, a specific autoantibody in primary biliary cirrhosis (PBC), has been common in Japan. However, there are some problems in the sensitivity of this ELISA, especially in PBC patients showing antimitochondrial antibody (AMA)-negative sera or low AMA titers by immunofluorescence. Recently, a new ELISA for anti-M2 was developed, using porcine heart mitochondrial protein as the antigen. We report here comparative studies of the new and the former anti-M2 ELISAs. Porcine heart mitochondrial protein was prepared and used as the antigen for the new ELISA for anti-M2. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of this protein showed three major M2 antigen proteins. As the second antibody, peroxidase-conjugated anti-human mouse monoclonal IgM, in addition to monoclonal IgG, was included. The sera of 171 PBC patients were examined. As controls, we examined the sera of 167 non-PBC patients and the sera of 115 normal controls. The cut-off index was set at 10 U/ml, based on the results for the normal controls. No sera from the non-PBC patients or the normal controls were positive for anti-M2 by either the new or the former ELISA. However, the positivity rate for anti-M2 in PBC patients with the new ELISA was 78%; in contrast, that with the former ELISA was only 54%; this difference was significant (P = 0.00001). In particular, in 65 patients showing AMA titers of 1 : 20 or less, the positivity rate with the new ELISA was 51%; in contrast, that with the former ELISA was only 17%. As the sensitivity of the new ELISA is significantly higher than that of the former ELISA, especially for sera from patients showing AMA-negativity or low titers of AMA, the new ELISA is considered to be more effective than the former ELISA for use in anti-M2 screening assays in patients with PBC.

Efficacy and long-term outcome of laparoscopic microwave coagulation or radiofrequency ablation therapy for surface-type hepatocellular carcinoma

Background:  Microwave or radiofrequency ablation therapy has been widely perfomed for hepatocellular carcinoma (HCC). Whereas ablation therapy is effective treatment, it cannot be perfomed easily, as is evident in several reports of severe complications. We treated surface‐type HCC under laparoscopy in avoidance of complications from March 1996. In the present study, we examined the efficacy and long‐term outcome of laparoscopic ablation therapy.

Anomalous plasma cyclic AMP responses to glucagon in patients with liver disease.

The purpose of the present study is to show anomalies of the plasma cAMP response of patients with hepatic disorders to a single injection of a low dose of glucagon (1 μg/kg body wt). The response was markedly blunted in patients with liver cirrhosis and potentiated in patients with acute or chronic hepatitis. This glucagon test is, therefore, promising for development as a simple diagnostic means without undertaking liver biopsy to distinguish cirrhosis from chronic hepatitis.

Development of a new enzyme-linked immunosorbent assay for the detection of anti-M2 in primary biliary cirrhosis

We developed a new enzyme-linked immunosorbent assay (ELISA) for the detection of antimitochondrial antibody (AMA)-M2 in sera from patients with primary biliary cirrhosis (PBC), using 2-oxo-acid dehydrogenase complex (2-OADC) purified from porcine myocardium as the antigen source. The immunoreactivity was tested in a total of 354 sera, including 63 sera from patients with PBC by our ELISA. In the sera, indirect immunofluorescence for AMA, former ELISA for anti-pyruvate dehydrogenase complex (PDC) and immunoblot assay were performed, respectively. Of the 63 sera from patients with PBC, 51 sera (81.0%) were positive for anti-M2 in the new ELISA. Thirty-eight of the 63 sera (60.3%) were positive for anti-PDC in the former ELISA; the difference was significant between them (P=0.011). None of the 291 control sera from healthy volunteers showed reactivity against 2-OADC in the new ELISA. Moreover, in comparison with the results of immunoblot analysis, sensitivity and specificity in our ELISA to the sera from patients with PBC were 100 and 92.3%, respectively. Our results indicate that the new ELISA for anti-M2 using 2-OADC is simple, rapid and sensitive enough for the detection of AMA specific to PBC.

Clinical significance of glucagon loading test in liver diseases

肝予備能力判定のための検査法として注目されつつあるグルカゴン負荷後の血漿cAMP濃度の経時的変動な観察した,グルカゴンは生理食塩水に溶解後1μg/kgな経静脈的に投与し,投与前,10, 15, 20, 30分後に採血し血漿cAMP濃度を測定した.健康成人,回復期の急性肝炎,慢性肝炎,肝硬変とも負荷10分後に血漿cAMP濃度は最高となり以後漸次低下した.空腹時血漿cAMP濃度は健康成人に比べて肝硬変で高く,慢性肝炎でも高い例が多かったが,各症例の差が大きく診断的意義は少なかった.グルカゴン負荷後の血漿cAMP濃度は,肝硬変で10分後健康成人に比べて上昇は少なかったがその差は有意でなく,また慢性肝炎では健康成人に比べて高い例が多かった.したがってグルカゴン負荷10分後の血漿cAMP濃度の空腹時濃度に対する比を算出すると肝硬変では健康成人に比べて有意に低く慢性肝炎では高かったので,両疾患の鑑別に本試験が有用と考えられた.