Yu W Yamamoto

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On April 21, 2008, four whooper swans were found dead at Lake Towada, Akita prefecture, Japan. Highly pathogenic avian influenza virus of the H5N1 subtype was isolated from specimens of the affected birds. The hemagglutinin (HA) gene of the isolate belongs to clade 2.3.2 in the HA phylogenetic tree.
Signal transducer and activator of transcription 3 (STAT3), which mediates biological actions in many physiological processes, is activated by cytokines and growth factors via specific tyrosine or serine phosphorylation, dimerization and nuclear translocation. A recent study has demonstrated, by using antibody to acetylated lysine, and a STAT3 mutant with(More)
We examined feathers of domestic ducks and geese inoculated with 2 different avian influenza virus (H5N1) genotypes. Together with virus isolation from the skin, the detection of viral antigens and ultrastructural observation of the virions in the feather epidermis raise the possibility of feathers as sources of infection.
H4N8 subtype avian influenza viruses were isolated from shorebirds in eastern Hokkaido. All the isolates shared >99.7% nucleotide homology, and all the viral genes except for PB1 were highly related to those of A/red-necked stint/Australia/1/04. Thus, the isolates were regarded as PB1 reassortants. The most similar PB1 gene was identified in A/mallard/New(More)
To the Editor: Free-range domestic ducks can be a key factor in regional spreading of Asian subtype H5N1 avian infl uenza (AI) virus (1–3). Even asymptomatic domestic ducks can shed the virus continuously from the oral cavity and cloaca (3–5). Therefore, early detection of infected ducks that are shedding the virus would reduce the risk of spreading AI(More)
The outbreak of Riemerella anatipestifer (RA) infection has been confirmed in meat-type domestic ducks (Anas platyrhynchos) for the first time in 27 years in Japan. In January 2014, increased mortality in a 14- to 21-day-old duck flock was reported to veterinary officials by the owner. The affected ducks exhibited reduced movement, ataxia and dorsal(More)
We examined whooper swans naturally infected with avian influenza virus (H5N1) to evaluate the possible zoonotic risk of swan feathers. Viruses were isolated from feather calami. Immunohistochemical testing revealed that virus antigens were present in the feather epidermis and feather follicle wall epidermis of some feathers. RT-PCR and genetic sequencing(More)
A hemagglutinating virus (8KS0813) was isolated from a red-necked stint. Hemagglutination inhibition and neutralization tests indicated that 8KS0813 was antigenically related to a prototype strain, APMV-6/duck/Hong Kong/18/199/77, but with an 8- and 16-fold difference, respectively, in their titers. The full genome sequence of 8KS0813 showed 98.6 %(More)
The pathogenicity of Newcastle disease (ND) virus, isolated from ND outbreak in vaccinated chickens, was evaluated through experiments. The pathogenicity indexes (mean death time (MDT); 58 hr, intracerebral pathogenicity index (ICPI); 1.7 and intravenous pathogenicity index (IVPI); 2.51) indicated that the ND virus was velogenic. The ND virus caused(More)
INTRODUCTION Kawasaki disease (KD) most commonly develops in infants, although its specific cause is still unclear. We report here a rare case of adult-onset KD which revealed to be concurrently infected by Coxsackievirus A4. CASE PRESENTATION The patient was a 37-year-old Japanese man who presented with fever, exanthema, changes in the peripheral(More)