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RAPD (random amplified polymorphic DNA) technique was applied to detect the genetic diversity in 3 species of abalone (Haliotis discus hannai Ino, Haliotis discus discus Reeve and Haliotis diverscolar Reeve). [...]

To the Editor: Aichi virus, a member of the Kobuvirus genus of the Picornaviridae family (1,2), is a positive-sense, single-stranded RNA virus with a genome of 8,280 nt and a [...]

Abstract Background Noroviruses (NoVs) are members of the family Caliciviridae and are emerging enteric pathogens of humans and animals. Some porcine NoVs are genetically similar to human strains and are classified into GII, like most epidemic human NoVs. So far, PoNoV have been exclusively detected in fecal samples of adult pig without clinical signs. Results Result showed that 2 of the 12 evaluated fecal samples were positive for PoNoVs, one of which was positive for PoNoV alone, and the other was coinfected with porcine circovirus and PoNoV. Phylogenetic and recombination analysis showed that the PoNoV positive alone strain was a recombinant new genotype strain. Experimental infection of miniature pigs with fecal suspensions confirmed that this strain can cause gastroenteritis in piglets. Conclusion This is the first report that recombinant new genotype PoNoV exised in pig herd of China, which cause diarrhea in pigs in nature condition. This find raised questions about the putative epidemiologic role of PoNoV.

Abstract Background Porcine sapovirus was first identified in the United States in 1980, hitherto, several Asian countries have detected this virus. In 2008, the first outbreak of gastroenteritis in piglets caused by porcine sapovirus in China was reported. The complete genome of the identified SaV strain Ch-sw-sav1 was sequenced and analyzed to provide gene profile for this outbreak. Methods The whole genome of Ch-sw-sav1 was amplified by RT-PCR and was sequenced. Sequence alignment of the complete genome or RNA dependent RNA polymerase (RdRp) gene was done. 3' end of ORF2 with 21-nt nucleotide insertion was further analyzed using software. Results Sequence analysis indicated that the genome of Ch-sw-sav1 was 7541 nucleotide long with two ORFs, excluding the 17 nucleotides ploy (A) at the 3' end. Phylogenetic analysis based on part of RdRp gene of this strain showed that it was classified into subgroup GIII. Sequence alignment indicated that there was an inserted 21-nt long nucleotide sequence at the 3' end of ORF2. The insertion showed high antigenicity index comparing to other regions in ORF2. Conclusion Ch-sw-sav1 shared similar genetic profile with an American PEC strain except the 21-nt nucleotide at the 3' end of ORF2. The insert sequence shared high identity with part gene of Sus scrofa clone RP44-484M10.

Abstract Background Several animal species can reportedly act as reservoirs for Hepatitis E virus (HEV), a zoonotic pathogen. HEV and antibody to the virus have been detected in a variety of animals including rodents. Pig and rat models for HEV have been established for HEV, but a nude mouse has not yet been developed. Methods Balb/c nude mice were inoculated with swine HEV, both orally and via intravenous injection to insure infection. Negative control and experimental contact-exposed groups of mice were also included in the study. The liver, spleen, kidney, jejunum, ileum, cecum and colon of each mouse from all three groups were collected for reverse transcription nested polymerase chain reaction (RT-nPCR) detection, indirect immunofluorescence observation and histopathologic examination. The sera from nude mice were tested for anti-HEV IgG by enzyme linked immunosorbent assay (ELISA). Activities of liver enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP), as well as total bilirubin (TBIL) were also measured in the sera of the nude mice. Results HEV antigens and HEV RNA were detected in liver, spleen, kidney, jejunum, ileum and colon both by indirect immunofluorescence and by RT-nPCR in all of the inoculated and in one of the contact-exposed nude mice. Histopathological changes were observed in the liver and spleen of these mice. Infected mice showed increased levels of AST, ALP, and anti-HEV IgG in sera. The livers of contact-exposed mice showed obvious histopathological damage. Conclusion Nude mice could be readily infected by HEV isolated from pigs. The nude mouse may therefore be a useful animal model for studying the pathogenesis of HEV.

Abstract In the present study, a genotype 4 HEV strain was identified in the fecal specimen from a seven months old infant with no symptom of hepatitis in Shanghai Children's hospital. The full capsid protein gene (ORF2) sequence of this strain was determined by RT-PCR method. Sequence analysis based on the full ORF2 sequence indicated that this HEV strain shared the highest sequence identity (97.6%) with another human HEV strain isolated from a Japanese patient who was infected by genotype 4 HEV during traveling in Shanghai. Phylogenetic analysis showed that this genotype 4 HEV was phylogenetically far from the genotype 4 HEV strain that was commonly prevalent in Shanghai swine group, suggesting that this strain may not come from swine group and not involved in zoonotic transmission in this area.