Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recently a new human virus, TT virus (TTV) was identified in the serum of a patient with post-transfusion hepatitis of unknown aetiology. Comparative sequence analysis of a 222 nt fragment of ORF 1 of TTV was performed to assess the genomic variability of this virus. Phylogenetic analysis of the nucleotide sequences of 76 TTV isolates collected in 17 countries segregated them into two major groups: TTV 1 and TTV 2. The TTV 1 group comprised two distinct subgroups, which corresponded to previously described TTV subtypes 1a and 1b. The TTV 2 group was separated into four main branches, two of which included sequences previously provisionally attributed as TTV types 2 and 3. Bootstrap resampling, however, did not support the reliability of this grouping, suggesting that the isolates in the TTV 2 group should be considered as subtypes of a single type rather than different TTV types.
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PMID:Sequence variability in the putative coding region of TT virus: evidence for two rather than several major types. 988 26

The main site of TT virus (TTV) replication remains unknown. Therefore, we have studied the presence and titres of TTV DNA in paired serum, liver and PBMC samples from 50 patients with liver disease (32 with chronic hepatitis B or C, seven with cryptogenic hepatitis and 11 with nonviral liver disease) were included. TTV DNA was analysed by polymerase chain reaction (PCR) using primers from the open reading frame 1 (ORF 1) and from the untranslated region (UTR) and titres were semiquantified by PCR using an external standard. TTV DNA was detected in 26% of serum, 24% of liver and 14% of PBMC samples with ORF 1 primers. When UTR primers were used, 70% of serum and liver samples and 64% of PBMC were TTV DNA positive. No differences between TTV positive and negative patients were found regarding epidemiological or biochemical parameters. Trypsin treatment and fluorescent in situ hybridization confirm the intracellular location of TTV in PBMC. The mean of TTV DNA titres was statistically higher in liver than in serum or PBMC. TTV titres in serum correlated with those in PBMC but not with those in liver. In conclusion, although the liver seems to be the main site for TTV replication, this virus is also able to infect PBMC.
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PMID:Presence of TTV DNA in serum, liver and peripheral blood mononuclear cells from patients with chronic hepatitis. 1111 56

Hepatitis-splenomegaly (HS) syndrome is an emerging disease in chickens in North America; the cause of this disease is unknown. In this study, the genetic identification and characterization of a novel virus related to human hepatitis E virus (HEV) isolated from bile samples of chickens with HS syndrome is reported. Based upon the similar genomic organization and significant sequence identity of this virus with HEV, the virus has been tentatively named avian HEV in order to distinguish it from human and swine HEV. Electron microscopy revealed that avian HEV is a non-enveloped virus particle of 30-35 nm in diameter. The sequence of the 3' half of the viral genome ( approximately 4 kb) was determined. Sequence analyses revealed that this genomic region contains the complete 3' non-coding region, the complete genes from open reading frames (ORFs) 2 and 3, the complete RNA-dependent RNA polymerase (RdRp) gene and a partial helicase gene from ORF 1. The helicase gene is the most conserved gene between avian HEV and other HEV strains, displaying 58-61% aa and 57-60% nt sequence identities. The RdRp gene of avian HEV shares 47-50% aa and 52-53% nt sequence identities and the putative capsid gene (ORF 2) of avian HEV shares 48-49% aa and 48-51% nt sequence identities with the corresponding regions of other known HEV strains. Phylogenetic analysis indicates that avian HEV is genetically related to, but distinct from, other known HEV strains. This discovery has important implications for HEV animal models, nomenclature and natural history.
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PMID:Genetic identification and characterization of a novel virus related to human hepatitis E virus from chickens with hepatitis-splenomegaly syndrome in the United States. 1156 38

Using reverse transcription-polymerase chain reaction with primers derived from well-conserved genomic areas among all four hepatitis E virus (HEV) genotypes (I-IV), the HEV sequence was identified in serum samples obtained from 3 (3%) out of 95 60- to 90-day-old pigs in Japan and characterized molecularly. In the partial sequence of open reading frame (ORF) 2 of 421 nucleotides, the three swine isolates (swJ570, swJ681, and swJ791) showed the highest similarity of 83-87% to genotype III HEV representing human and swine strains (US1, US2, and swUS1) in the United States. The full-length nucleotide sequence of swJ570 consisted of 7225 nucleotides excluding the poly(A) tail and contained ORF 1 encoding 1703 amino acids (aa), ORF2 encoding 660 aa, and ORF3 encoding 122 aa. The swJ570 strain was most closely related to a Japanese strain (JRA1), which had been obtained from a hepatitis patient who had not traveled outside Japan. The overall nucleotide sequence identity between them was 89% and the deduced amino acid sequence identities of ORF1, ORF2, and ORF3 were 96, 99, and 98%, respectively. These results indicate that a certain proportion of pigs in Japan are HEV-viremic and may act as reservoirs of HEV infection, and that the presence of an indigenous strain(s) of HEV should be taken into consideration for the diagnosis of acute hepatitis in Japan.
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PMID:Analysis of the complete genome of indigenous swine hepatitis E virus isolated in Japan. 1174 Dec 79

In Argentina, a country considered non-endemic for hepatitis E virus (HEV) infection, serologic evidence of HEV infection has been observed in different human population groups. In other countries, a high degree of genetic relatedness has been observed between human and swine HEV genotype 3 sequences, suggesting zoonosis as one probable route of infection. This is the first identification of swine HEV in South America. HEV RNA was detected and sequenced in the ORF 1 and ORF 2 regions from swine fecal samples from a herd located in Pergamino, in the province of Buenos Aires. These strains all group into genotype 3 and exhibit a close relationship to two novel HEV variants previously identified in Argentina from sporadic acute cases of non-A to -C hepatitis in humans. In addition, using a modified commercial ELISA, the presence of anti-HEV antibodies was surveyed in five provinces across the country and all five showed a prevalence of HEV antibodies, ranging from 4% to 58%. The results suggest that swine could be an important reservoir for virus transmission in Argentina as has been suggested for other non-endemic areas. The Argentine human strains and swine strain described in this article seem to be closely related to a human Austrian strain, suggesting a potential European origin of HEV infection in these cases.
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PMID:Identification of the first strain of swine hepatitis E virus in South America and prevalence of anti-HEV antibodies in swine in Argentina. 1706 23

Strains of hepatitis E virus (HEV) isolated from Argentinian patients with sporadic hepatitis, as well as from swine from Argentina, belong to genotype 3. HEV genotype 3 variants have been described associated with acute liver failure (ALF) in adults from Japan and the United Kingdom. In Argentina, 30% of ALF in adults and children are of unknown aetiology. To study if HEV could be an aetiological agent associated with ALF in children, serum and/or fecal samples fJom 35 children (mean age: 6 years, 20 female, 15 male) were analyzed during 2003 and 2004. HEV RNA was detected by RT-nested PCR with primers designed within ORF 1 and ORF 2 regions. HEV RNA could be detected in three cases. Two were 12-year-old boys fom Buenos Aires province and the third was a 3-year-old girl from Corrientes province. Sequence analysis indicates that the three isolates are distinct from each other but all belong to genotype 3, exhibiting a close relationship with swine and human strains fJom sporadic cases of HEV, previously reported in Argentina. This data suggests a potential link between ALF and HEVin children in Argentina and indicates the need for the determination of HEV status in the differential diagnosis in ALE Further studies would aid in determining the true impact of this infection in Argentina and the potential benefits of a vaccine against HEV presently in phase III trials.
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PMID:[Molecular characterization of hepatitis E virus in three acute liver failure cases in children in Argentina]. 1740 88

Nonstructural protein 1 (nsp1), a 28-kDa protein in the bovine coronavirus (BCoV) and closely related mouse hepatitis coronavirus, is the first protein cleaved from the open reading frame 1 (ORF 1) polyprotein product of genome translation. Recently, a 30-nucleotide (nt) cis-replication stem-loop VI (SLVI) has been mapped at nt 101 to 130 within a 288-nt 5'-terminal segment of the 738-nt nsp1 cistron in a BCoV defective interfering (DI) RNA. Since a similar nsp1 coding region appears in all characterized groups 1 and 2 coronavirus DI RNAs and must be translated in cis for BCoV DI RNA replication, we hypothesized that nsp1 might regulate ORF 1 expression by binding this intra-nsp1 cistronic element. Here, we (i) establish by mutation analysis that the 72-nt intracistronic SLV immediately upstream of SLVI is also a DI RNA cis-replication signal, (ii) show by gel shift and UV-cross-linking analyses that cellular proteins of approximately 60 and 100 kDa, but not viral proteins, bind SLV and SLVI, (SLV-VI) and (iii) demonstrate by gel shift analysis that nsp1 purified from Escherichia coli does not bind SLV-VI but does bind three 5' untranslated region (UTR)- and one 3' UTR-located cis-replication SLs. Notably, nsp1 specifically binds SLIII and its flanking sequences in the 5' UTR with approximately 2.5 muM affinity. Additionally, under conditions enabling expression of nsp1 from DI RNA-encoded subgenomic mRNA, DI RNA levels were greatly reduced, but there was only a slight transient reduction in viral RNA levels. These results together indicate that nsp1 is an RNA-binding protein that may function to regulate viral genome translation or replication but not by binding SLV-VI within its own coding region.
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PMID:Bovine coronavirus nonstructural protein 1 (p28) is an RNA binding protein that binds terminal genomic cis-replication elements. 1935 73