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Query: UMLS:C0019158 (
hepatitis
)
30,205
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Recently, GBV-C and HGV-two isolates of the same new flavivirus-were identified in serum samples of patients with indeterminate
hepatitis
and posttransfusion hepatitis, respectively. The pathogenic relevance of these viruses is still uncertain. As viral infections are presumed to trigger autoimmune processes, we investigated GBV-C in autoimmune
hepatitis
as well as in cryptogenic
hepatitis
, and compared the prevalences to patients with chronic viral hepatitis and those of blood donors. We found only a slightly higher prevalence of the virus in cryptogenic (12%) and autoimmune
hepatitis
type I-III (6.7%, 10%, and 12.5%) compared to blood donors (4.7%). In contrast, patients with viral hepatitis B, C, and D were more frequently infected with GBV-C (16%, 20%, 36%). These results suggest that GBV-C is not a major cause for inducing autoimmunity and leading to autoimmune
hepatitis
. We analyzed the nucleic acid sequences of a representative number of GBV-C positive patients (24/42) and found a broad range of nucleotide similarity in the NS3
helicase
region (74-100%) among the isolates and the prototype sequences. However, we could not identify a specific sequence, which would point to a certain strain or subtype of the virus associated with autoimmune or cryptogenic liver disease.
...
PMID:GBV-C/HGV is not the major cause of autoimmune hepatitis. 900 30
In 1995, a new human
hepatitis
virus belonging to the family Flaviviridae was described and designated
hepatitis
GBV-C. To investigate variations within the genome of GBV-C and to study the relationship of GBV-C to GBV-A/B or hepatitis C virus (HCV), we established a detection system using reverse transcriptase polymerase chain reaction (RT-PCR) of the putative
helicase
region (NS3). So far, isolates derived from 14 different GBV-C-positive sera were analyzed (GBV-C/S3-36), showing 80.1-89.4% (mean: 85%) identical nucleotides. The deduced amino acid sequences revealed 97.3% homology. Nucleotide sequences of GBV-C/S3-36 revealed about 60% identity to GBV-A as well as to HCV, but only 56% identity to GBV-B. Amino acid sequences revealed 73.4 and 68.6% similarity to GBV-A and GBV-B, respectively, but a slightly higher percentage of 78.5% to HCV sequences. Thus, according to the putative GBV-C
helicase
sequence, a subtyping of GBV-C into different genotypes may be necessary.
...
PMID:Sequence analysis of hepatitis GB virus C (GBV-C) isolates from 14 patients. 902 80
Hepatitis B virus(HBV), hepatitis C virus(HCV), and human immunodeficiency virus(HIV) infections are common among intravenous drug abusers, with a global distribution. The recently discovered
hepatitis
GB virus C(HGBV-C)/hepatitis G virus(HGV) has been linked to blood-borne non-A-E
hepatitis
. HGBV-C RNA was determined by the polymerase chain reaction with primers deduced from a
helicase
-like region in 189 patients with type C chronic liver diseases. Overall, HGBV-C RNA was detected in 22(11.6%) patients. The prevalence of HGBV-C RNA was estimated according to the suspected transmission routes(blood transfusion, intravenous drug abuse, tattooing and unknown) of HCV. 22.7-25.0% of type C
hepatitis
patients with a history of intravenous drug abuse were positive for HGBV-C RNA. These results indicate that HGBV-C is transmitted frequently in intravenous drug abusers coinfected with HCV.
...
PMID:[Infection with hepatitis GB virus C in intravenous drug abusers with type C chronic liver diseases]. 908 56
New
hepatitis
viruses, hepatitis G virus(HGV) and
hepatitis
GB virus C(HGBV-C), were reported from two groups of researchers. Now these two are thought to be similar but HGV genome(U44402) and HGBV-C genome(U36380) do not have the same sequence. We compare these two sequences in both nucleotide and aminoacid analyses. Homology of nucleotide between HGV and HGBV-C is 83.8% in 5'NC region, 88.8% in core, 85.1% in E1, 85.7% in E2, 85.1% in NS2-3, 84.5% in NS4A, 86.8% in NS4B-5A, 88.6% in NS5B and 18.0% in 3'NC. The length of 3'NC is quite different between HGV and HGBV-C. Homology of aminoacid between these two viruses is 82.9% in core region, 87.3% in E1, 91.0% in E2, 97.4% in NS2-3, 93.8% in NS4A, 96.2% in NS4B-5A and 96.6% in NS5B. Especially
helicase
and replicase regions are highly conserved in 99.0% and 92.7% of aminoacid homology, respectively.
...
PMID:[Comparison between HGV genome and HGBV-C genome]. 908 65
In previous studies, human
hepatitis
viruses have been experimentally transmitted to New World monkeys of the genus Saguinus (tamarins). Recently, two Flaviviridae-like agents (GBV-A and GBV-B) were identified in tamarins that developed
hepatitis
following inoculation with serum of the 11th tamarin passage of a potentially new human
hepatitis
agent. However, it was not shown that these viruses originated from the initial inoculum. We here report the discovery of indigenous species-specific viruses related to GBV-A in several species of New World monkeys and suggest that GBV-A virus was fortuitously acquired during passage in tamarins. Sera or plasma from 98 wild-caught New World monkeys representing 10 different species was tested by RT-PCR with conserved degenerate primers to the 5' noncoding region of the genome. Viral sequences were identified in 33 animals and sequence analysis was performed on the amplicons. In addition, the genomic region corresponding to the putative NS3 RNA helicase of GBV-A was amplified from most positive animals and sequenced. We detected GBV-A-like viruses in 13 (35%) of 37 S. mystax, 7 (78%) of 9 S. nigricollis, 3 (25%) of 12 S. labiatus, 2 (50%) of 4 S. oedipus, 2 (100%) of 2 Callithrix jacchus, and 6 (50%) of 12 Aotus trivirgatus monkeys. Each positive animal was infected with a unique strain of the GBV-A-like viruses. Analysis of the 5' NC and NS3
helicase
sequences revealed that these viruses could be classified into 5 major genetic groups with genetic distances equivalent to or greater than those found among major genetic groups of hepatitis C virus. Species-specific GBV-A-like viruses were found in S. mystax, S. nigricollis, S. oedipus, C. jacchus, and A. trivirgatus species. The viruses specific for S. nigricollis were closely related to GBV-A, suggesting that GBV-A was acquired by passage through this species during the initial transmission studies. The natural history of the GBV-A-like viruses was studied in serial serum samples from 9 S. mystax and 2 A. trivirgatus monkeys. Each animal was chronically infected and the viral strain did not vary during 9-27 months of follow-up. Finally, we demonstrated that four S. mystax were positive upon arrival to the United States from the country of origin. No apparent disease was associated with chronic infection of the GBV-A-like viruses. In conclusion, many New World monkeys are persistently infected with indigenous species-specific viruses that may represent a new genus within the virus family Flaviviridae.
...
PMID:Five new or recently discovered (GBV-A) virus species are indigenous to New World monkeys and may constitute a separate genus of the Flaviviridae. 912 55
Infection with putative non-A to E
hepatitis
virus, designated GB virus C (GBV-C), was surveyed in 286 patients with chronic liver disease in Japan. RNA of GBV-C was detected, by reverse-transcription polymerase chain reaction with nested primers from the 5'-noncoding region, in 19 patients (6.6%) at a frequency higher (P < 0.001) than in three of 275 (1.1%) normal controls. It was detected in three of 83 (4%) patients with hepatitis B virus infection, 15 of 188 (8%) patients with hepatitis C virus infection, and one of 12 (8%) patients without evidence of ongoing infection with hepatitis B or C virus. GBV-C RNA was detected in nine of 186 (5%) patients with chronic hepatitis aged 51.2 +/- 13.3 years, six of 64 (9%) with liver cirrhosis aged 62.9 +/- 11.4 years, and four of 36 (11%) with hepatocellular carcinoma aged 62.0 +/- 11.1 years. Nucleotide sequences of 100 base pairs in the
helicase
region of GBV-C isolates from the 19 patients varied up to 21%, while sequences of 33 deduced amino acids were conserved and differed only by up to 6%. These results indicate that infection with GBV-C in patients with non-B, non-C chronic liver disease would not be frequent, although the sensitivity of the detection method could be improved. Coinfection of GBV-C with hepatitis B or C virus, as well as the duration of infection, might accelerate the progression of chronic liver disease.
...
PMID:Infection with GB virus C in patients with chronic liver disease. 913 80
GBV-C or hepatitis G virus (GBV-C/HGV) is a novel RNA virus with similarities to members of the Flaviviridae family, especially hepatitis C. Viral RNA is detected in about 1.5% of American blood donors, with higher prevalence in multiply transfused patients and in individuals with
hepatitis
or liver disease. Some cases of aplastic anaemia follow apparent non-A, non-B, non-C viral hepatitis, and GBV-C viraemia has been described in three case reports of
hepatitis
-associated aplastic anaemia. We tested clinical samples from patients with aplastic anaemia with or without recent
hepatitis
for the presence of GBV-C/HGV. Virus was detected in a total of 15/57 (26.3%) of patients with aplastic anaemia and 12/52 (23.1%) of multiply transfused control patients. Sequencing of the 188 base pair NS3
helicase
PCR product in the serum of five individuals indicated the same high degree of sequence variation as has been seen among other isolates of the virus. GBV-C/HGV does not appear to be implicated in the aetiology of aplastic anaemia.
...
PMID:Prevalence of GBV-C/HGV, a novel 'hepatitis' virus, in patients with aplastic anaemia. 916 22
The presence of
hepatitis
GB virus C (GBV-C), also known as hepatitis G virus (HGV), and hepatitis C virus (HCV) were investigated in sera from 45 hemophiliacs from nine locations in Nicaragua using a nested polymerase chain reaction (PCR). Primers used to detect GBV-C and HCV derived from the
helicase
region and 5'UTR, respectively. Seventeen (38%) patients were positive for GBV-C RNA in serum by PCR. Twelve (27%) patients were positive for HCV RNA by PCR. Six (13%) of these were coinfected with GBV-C. Anti-HCV was detected in all the 12 HCV RNA positive hemophiliacs and in another 14 (31%) individuals, in whom GBV-C RNA was found in 2. Ten patients (22%) lacked markers for both GBV-C and HCV. The mean age of the patients positive for GBV-C but negative for HCV by PCR was significantly lower than for those negative for GBV-C but positive for HCV by PCR (P < 0.05; Student's t-test), indicating that the risk for this group of hemophiliacs to acquire GBV-C infection is higher as compared to the risk of acquiring HCV infection. Eleven GBV-C strains were sequenced in the 5'UTR. Sequence comparison to previously published GBV-C strains revealed that all 11 strains were more similar to Asian strains than to strains of European and African origin. Sequences in the NS5-B region were available for 8 HCV strains, all of which were found to belong to genotype 1a. The similarity of the Nicaraguan GBV-C strains to strains from Asia indicates that the GBV-C strains in the region presumably have an Amerindian origin. It is also considered that the HTLV II strains in the New World aboriginal populations are ancient and brought there by the ancestral Amerindian populations from Asia. Further, the genotype F of hepatitis B virus, known to represent the strains in populations with Amerindian background, predominates in Central American populations with Hispanic background. It remains to be clarified why Amerindian strains of GBV-C as well as of HBV predominate also in populations with mixed ethnic background in Central America.
...
PMID:High prevalence of GB virus C strains genetically related to strains with Asian origin in Nicaraguan hemophiliacs. 917 60
The newly cloned and characterized
hepatitis
GB virus-C (HGBV-C), which is the same virus as the independently discovered hepatitis G virus, has a global distribution, is transmitted parenterally, and causes chronic viremia. The pathological consequences of infection with HGBV-C are uncertain, and its hepatocarcinogenic potential is unknown. We used a case-control format to compare the prevalence of HGBV-C infection in 167 southern African blacks with hepatocellular carcinoma (HCC) and 167 race-, age-, and sex-matched hospital-based control subjects, and to test for possible interactive effects between this virus and hepatitis B and C viruses in the development of the tumor. The presence of HGBV-C ribonucleic acid was detected in serum samples by reverse transcription, amplification of the resulting complementary deoxyribonucleic acid by the polymerase chain reaction (PCR), and Southern hybridization using a probe from the NS3/
helicase
region of the genome. Serum samples were also tested for the presence of hepatitis B virus surface antigen, antibodies to hepatitis C virus, and hepatitis C virus ribonucleic acid. Individuals infected with HGBV-C did not have an increased relative risk of developing HCC (relative risk 0.9; 95% confidence limits 0.5, 1.7). Moreover, co-infection with HGBV-C did not further increase the risk of tumor development in patients who were chronically infected with hepatitis B and/or C viruses. HGBV-C is unrelated to hepatocellular carcinoma development in black Africans.
...
PMID:Does hepatitis GB virus-C infection cause hepatocellular carcinoma in black Africans? 930 6
The 3C-like proteinase (3CLpro) of mouse
hepatitis
virus (MHV) is predicted to cleave at least 11 sites in the 803-kDa gene 1 polyprotein, resulting in maturation of proteinase, polymerase, and
helicase
proteins. However, most of these cleavage sites have not been experimentally confirmed and the proteins have not been identified in vitro or in virus-infected cells. We used specific antibodies to identify and characterize a 22-kDa protein (p1a-22) expressed from gene 1 in MHV A59-infected DBT cells. Processing of p1a-22 from the polyprotein began immediately after translation, but some processing continued for several hours. Amino-terminal sequencing of p1a-22 purified from MHV-infected cells showed that it was cleaved at a putative 3CLpro cleavage site, Gln_Ser4014 (where the underscore indicates the site of cleavage), that is located between the 3CLpro domain and the end of open reading frame (ORF) 1a. Subclones of this region of gene 1 were used to express polypeptides in vitro that contained one or more 3CLpro cleavage sites, and cleavage of these substrates by recombinant 3CLpro in vitro confirmed that amino-terminal cleavage of p1a-22 occurred at Gln_Ser4014. We demonstrated that the carboxy-terminal cleavage of the p1a-22 protein occurred at Gln_Asn4208, a sequence that had not been predicted as a site for cleavage by MHV 3CLpro. Our results demonstrate the usefulness of recombinant MHV 3CLpro in identifying and confirming cleavage sites within the gene 1 polyprotein. Based on our results, we predict that at least seven mature proteins are processed from the ORF 1a polyprotein by 3CLpro and suggest that additional noncanonical cleavage sites may be used by 3CLpro during processing of the gene 1 polyprotein.
...
PMID:Mouse hepatitis virus 3C-like protease cleaves a 22-kilodalton protein from the open reading frame 1a polyprotein in virus-infected cells and in vitro. 949 85
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