Hiroaki Okamoto

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International standardization and coordination of the nomenclature of variants of hepatitis C virus (HCV) is increasingly needed as more is discovered about the scale of HCV-related liver disease and important biological and antigenic differences that exist between variants. A group of scientists expert in the field of HCV genetic variability, and those(More)
Among ten patients who contracted sporadic acute or fulminant hepatitis E between 2001 and 2002 in Hokkaido, Japan, nine (90 %) had a history of consuming grilled or undercooked pig liver 2-8 weeks before the disease onset. We tested packages of raw pig liver sold in grocery stores as food in Hokkaido for the presence of hepatitis E virus (HEV) RNA by(More)
The family Hepeviridae consists of positive-stranded RNA viruses that infect a wide range of mammalian species, as well as chickens and trout. A subset of these viruses infects humans and can cause a self-limiting acute hepatitis that may become chronic in immunosuppressed individuals. Current published descriptions of the taxonomical divisions within the(More)
Hepatitis E virus (HEV) is the sole member of the genus Hepevirus in the family Hepeviridae. HEV is transmitted primarily by the fecal-oral route, and water-borne epidemics are characteristic of hepatitis E in many developing countries in Asia, Africa and Latin America where sanitation conditions are suboptimal. Accumulating lines of evidence indicate that(More)
Using PCR with primers derived from a non-coding region of the human TT virus (TTV) genome, the TTV sequence in serum samples obtained from pigs (Sus domesticus), dogs (Canis familiaris) and cats (Felis catus) was identified and the entire genomic sequence was determined for each representative isolate. Three TTV isolates (Sd-TTV31 from a pig, Cf-TTV10 from(More)
We recently identified a novel human virus classifiable into a third group in the genus Anellovirus, tentatively designated torque teno midi virus (TTMDV), with a circular DNA genome of 3.2 kb and genomic organization resembling those of torque teno virus (TTV) (3.8 to 3.9 kb) and torque teno mini virus (TTMV) (2.8 to 2.9 kb). TTMDV was characterized by(More)
TT virus (TTV) was recovered from the sera of tupaias (Tupaia belangeri chinensis) by PCR using primers derived from the noncoding region of the human TTV genome, and its entire genomic sequence was determined. One tupaia TTV isolate (Tbc-TTV14) consisted of only 2199 nucleotides (nt) and had three open reading frames (ORFs), spanning 1506 nt (ORF1), 177 nt(More)
Hepatitis E virus (HEV) is a major cause of acute hepatitis in many developing countries. HEV is transmitted principally by the fecal-oral route, and water-borne epidemics are characteristic of hepatitis E. Recently, there is growing consensus that HEV-associated hepatitis also occurs among individuals in industrialized nations who had no history of travel(More)
PURPOSE This multicenter, phase II study was conducted to evaluate the activity of amrubicin, a topoisomerase II inhibitor, against refractory or relapsed small-cell lung cancer (SCLC). PATIENTS AND METHODS SCLC patients with measurable disease who had been treated previously with at least one platinum-based chemotherapy regimen and had an Eastern(More)
To investigate the prevalence of hepatitis B virus (HBV) genotypes and characteristics of HBV isolates among Japanese patients infected with human immunodeficiency virus type 1 (HIV), serum samples collected between September 1990 and March 2002 from 471 HIV-infected patients (age, 38.8 +/- 11.4 [mean +/- standard deviation] years; male, 90%) were tested(More)