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

The clinical significance and course of acute hepatitis G virus (HGV) infection were studied by measuring HGV RNA and antibody to HGV envelope protein E2 (HGV-E2 antibody). A total of 59 patients with transfusion-associated non-A, non-B hepatitis, who were followed-up for more than 1 year, were selected retrospectively. HGV RNA was measured by reverse transcriptase (RT) and nested polymerase chain reaction (PCR) was performed, using primer sets, in the 5'-non-coding region of the HGV genome. HGV-E2 antibody was measured by enzyme-linked immunosorbent assay (ELISA) using recombinant E2 protein. Of the 59 patients, 51 (86%) were infected with hepatitis C virus (HCV) and 12 (20%) were infected with HGV; 11 of the 12 with HGV infection were also infected with HCV. HGV viraemia was cleared during the follow-up period in seven of the 12 patients with HGV infection. All these seven patients seroconverted for HGV-E2 antibody just before or just after the clearance of HGV viraemia. In contrast, all five patients without clearance of HGV viraemia were negative for HGV-E2 antibody (P = 0.0013). Of seven patients with continuous HGV viraemia at 1 year from the onset of acute hepatitis, four with HCV RNA showed chronic elevation of alanine aminotransferase (ALT) but three without HCV RNA did not. The severity of acute hepatitis was similar between patients with both HGV and HCV infections and in those with HCV infection alone. The majority of patients with HGV infection cleared the virus during long-term follow-up. Appearance of HGV-E2 antibody was associated with the clearance of HGV viraemia. An abnormal ALT level was noted to depend on HCV infection but not on HGV infection in both the acute and chronic phases of transfusion-associated hepatitis.
...
PMID:Evolution of hepatitis G virus infection and antibody response to envelope protein in patients with transfusion-associated non-A, non-B hepatitis. 965 67

Forty-eight persons (M = 45, F = 3; age range = 20-53, mean = 32.2) affected with chronic hepatitis C were tested for HGV/GBV-C RNA and HCV-RNA by nested PCR and DEIA in serum and in liver specimens to evaluate the prevalence and the impact of HGV/GBV-C coinfection in patients with chronic HCV-related hepatitis. Sera were also assayed for antibodies to HGV/GBV-C E2 protein. Serum HGV/GBV-RNA could be detected in nine (19%) patients, and anti-E2 antibodies in 22 (46%) patients. The presence of HGV/GBV-C RNA or anti-E2 antibodies was mutually exclusive. The cumulative prevalence of HGV/GBV-C infection was 65% (31/48); the majority of these patients (26/31, 84%) were intravenous drug users (IVDUs). In eight of nine patients viraemic for HGV/GBV-C, RNA positivity could be revealed even in liver specimens; these eight patients were also positive for HCV-RNA both in serum and the liver and did not exhibit any specific association with HCV genotype. HGV/GBV-C RNA negative strand RT-PCR testing was negative in all of the eight liver specimens, providing little support to the hypothesis that liver represents the primary site of HGV/GBV-C replication. Moreover, patients with HGV/GBV-C and HCV coinfection were comparable to those with HCV infection alone in terms of biochemistry and liver histology.
...
PMID:HGV/GBV-C in liver tissue and in sera from patients with chronic hepatitis C. 979 85

The review article summarizes up-to-now identified properties and clinical impact of new hepatotropic virus--hepatitis G virus (HGV, GBV). From its discovery by Simons in 1995 the possible role in high number of cryptogenic hepatitis is intensively studied. Cryptogenic hepatitis represents 20-25% of all chronic hepatitis cases in the USA. HGV is a single strain RNA virus of flaviviruses group. According to nucleotides sequence is the virus a distant relative of hepatitis C virus. The results of previous studies suggest that the HGV virus is more a lymphotropic than a hepatotropic virus. The prevalence of chronic HGV infection in accordance with geographical differences ranges from 0.4 to 4.9%. Risk groups with highest HGV positivity are intravenous drugs abusers, promiscuous persons, repeated transfusion patients. Proven routes of transmission involve parenteral and sexual transmission, vertical transmission can not be excluded. On the basis of available information mild course of the disease with minimal transaminases elevation is anticipated. Clinical studies have revealed rapid healing, late recovery and also the transition into chronic form. Recent scientific interest is focused on clinical severity of the infection and co-infection with other hepatotropic viruses assessment. Diagnostic of HGV is possible with reverse transcription using PCR (polymerase chain reaction) or enzyme immunoassay identifying the anti-E2 protein. The effects of interferon will be evaluated after termination of large clinical studies. (Tab. 2, Fig. 2, Ref. 15.)
...
PMID:[Hepatitis G--2 years after its discovery]. 1049 99

The incidence and clinical significance of hepatitis G virus (HGV) is still not fully known. The aim of our study was to assess the frequency of HGV RNA and antibody to HGV E2 protein (anti-E2) in Polish blood donors and patients with hepatitis, and to compare the sequence of HGV clones with those reported by others. Two-hundred and nineteen blood donors and 83 patients with hepatitis were studied. HGV was detected in 3.2% and anti-E2 in 24.2% of blood donors and in 26.5% and 8.4% of patients with hepatitis, respectively. HGV was detected as a co-infection with HCV in four of 18 patients with chronic hepatitis, in four of 16 patients with acute hepatitis and in one of six patients with fulminant liver failure (FLF), and as a co-infection with HBV in one of six patients with FLF and in three of 10 patients with chronic hepatitis. In non-A-C hepatitis, eight of 23 patients with acute hepatitis and one of four patients with FLF were positive for HGV but all 10 patients with chronic cryptogenic hepatitis were negative. In the follow-up studies of patients with HGV alone, a correlation with viraemia and clinical symptoms was observed in two patients, but in three others HGV RNA was detected in spite of clinical resolution. Two HGV clones were sequenced, and the sequence of the HGV helicase region of the HGV isolates from donor and patient were homologous to those described by others. Hence, the frequency of HGV RNA in blood donors is similar to that obtained in other countries but the anti-E2 (marker of a past infection) frequency is higher. The incidence of HGV RNA and anti-E2 in hepatitis patients suggests that HGV plays a role in liver pathology, but careful analysis of individual cases does not confirm this.
...
PMID:Analysis of hepatitis G virus infection markers in blood donors and patients with hepatitis. 1060 66

The role of GBV-C/HGV in the aetiology of acute non A-E hepatitis and its impact on the course of acute hepatitis of defined aetiology were investigated by detecting viral RNA by RT-PCR and antibody to the E2 protein of GB virus C (anti-E2) by EIA. Ninety-eight patients with acute nonA-E hepatitis, 35 patients with acute hepatitis A, 63 with acute hepatitis B, 29 with acute hepatitis C and 270 controls were enrolled in this study. The prevalence of GBV-C/HGV RNA was similar among patients with acute nonA-E hepatitis (3.1%), with acute hepatitis A (2.9%), and controls (3.7%), but significantly higher (P < 0.05) among those with hepatitis B or C (19.0% and 48.3%, respectively). Similar figures were obtained considering the total rate of GBV-C/HGV exposure (viral RNA or anti-E2 positivity). The majority (24/30 or 80%) of GBV-C/HGV RNA positive patients reported a parenteral source of exposure whereas the remaining 20% denied having known risk factors. The liver function test values and the rate of chronic hepatitis B and C were similar in patients co-infected and in those not co-infected with GBV-C/HGV. This study excludes a significant role of GBV-C/HGV infection in the aetiology of acute nonA-E hepatitis in Italy. Concomitant GBV-C/HGV and HBV or HCV infection does not worsen the clinical course of illness among patients with acute hepatitis.
...
PMID:GBV-C/hepatitis G virus in acute nonA-E hepatitis and in acute hepatitis of defined aetiology in Italy. 1074 33

Mechanisms determining the chronicity or the pattern of clinical course of hepatitis C virus (HCV) infections have not been clarified. Recently, CD81 was reported to bind the E2 protein of HCV and was suggested to function as a cellular receptor for HCV. Accordingly, the hypothesis was examined that CD81 polymorphism, if it exists, might correlate with certain clinical courses of HCV infection. CD81 cDNA sequences were determined from peripheral blood mononuclear cells (PBMCs). Twenty-four Japanese subjects were enrolled initially as follows: patients with chronic hepatitis C without cirrhosis (n = 3), patients with cirrhosis (n = 3), patients with cirrhosis complicated by hepatocellular carcinoma (HCC) (n = 3), patients with persistent HCV viremia without ALT elevation (n = 3), those with positive anti-HCV antibodies without evidence of HCV viremia (n = 3), and healthy volunteers (n = 9). In all PBMCs samples analyzed, no polymorphism was found in the CD81 cDNA sequence. The sequence was different, however, from the one reported previously at three nucleotide positions: a transversion to thymine instead of cytosine at nt 1130, a deletion at nt 1206, and a guanine insertion at nt 71. Subsequently, CD81 cDNA sequences from PBMCs and HCC tissue were compared among the other 6 patients with chronic hepatitis C bearing HCC. A comparative study of the CD81 sequences from HCC and PBMCs revealed that various nucleotide mutations existed only in the HCC samples in 3 out of 6 patients. Several mutations in the 3' non-coding region of CD81 cDNA were observed exclusively in HCC tissue suggesting its possible role in hepatocarcinogenesis. Because of the absence of polymorphisms, however, CD81 is unlikely to affect the progression of chronic hepatitis C in terms of chronicity, hepatitis activity, or disease stage.
...
PMID:CD81 nucleotide mutation in hepatocellular carcinoma and lack of CD81 polymorphism in patients at stages of hepatitis C virus infection. 1113 Aug 83

Hepatitis C virus was identified in 1989 as the main causative agent of non-A, non-B and was followed by the recognition of a high prevalence of hepatitis C virus infection after transfusion of infected blood or blood products and in association with intravenous drug abuse. The availability of sensitive and reliable techniques to screen blood for hepatitis C virus has reduced the incidence of post-transfusion hepatitis. True healthy carriers of hepatitis C virus did not exist. Approximately 95% of hepatitis C virus infected individuals can be identified by third generation anti-hepatitis C virus testing. Retrospective studies of iatrogenic hepatitis C virus infection are the main source of the natural history of the disease. The distribution of different hepatitis C virus genotypes varies according to the geographic region. In South America, Europe, The United States and Japan hepatitis C virus genotypes 1, 2 and 3 account for the majority of the infections, being (sub)type 1b the most prevalent. Epidemiological parameters (age, risk factors and duration of infection) may be associated with hepatitis C virus genotypes (intravenous drug abuse with types 1-a and 3-a and 1-b with post-transfusion hepatitic C). Subtype 1-b, lead to a more severe course of viral infection, with ultrastructural alterations of the mitochondria, and greater impairment of the process of oxidative phosphorylation. No increased production of free radicals may influence the evolution of the liver disease by an enhancement of the cytopathic effect of hepatitis C virus. The clinical significance of intrahepatic hepatitis C virus level in patients with chronic hepatitis C virus infection is not determined by host factors (age of patient, mode or duration of infection) or by virus factors (hepatitis C virus genotypes) and, repeatedly negative RT-PCR for hepatitis C virus RNA in serum does not indicate absence of hepatitis C virus from the liver. The association between autoimmunity and hepatitis C virus is questioned. Markers of its does occur with high frequency in these patients. Modulation of immune responses to hepatitis C virus envelope E2 protein following injection of plasmid DNA, has been used for induction of specific response to hepatitis C virus. The spectrum of such responses could likely be broadened by combining plasmids, delivery routes, and other forms of encoded immunogens (peptide vaccines). These may be important to the development of a vaccine against the high mutable hepatitis C virus. The pathogenic role of novel DNA virus (TTV) is under spotlight. As with hepatitis G, however, the association of TTV with disease is far from clear.
...
PMID:[Chronic viral hepatitis C. Part 1. General considerations]. 1123 73

Hepatitis C virus (HCV) is the major etiologic agent of non-A, non-B hepatitis. HCV infection frequently causes chronic hepatitis, which progresses to liver cirrhosis and hepatocellular carcinoma. Since the discovery of HCV in 1989, a large number of genetic analyses of HCV have been reported, and the viral genome structure has been elucidated. An enveloped virus, HCV belongs to the family Flaviviridae, whose genome consists of a positive-stranded RNA molecule of about 9.6 kilobases and encodes a large polyprotein precursor (about 3000 amino acids). This precursor protein is cleaved by the host and viral proteinase to generate at least 10 proteins: the core, envelope 1 (E1), E2, p7, nonstructural (NS) 2, NS3, NS4A, NS4B, NS5A, and NS5B. These HCV proteins not only function in viral replication but also affect a variety of cellular functions. HCV has been found to have remarkable genetic heterogeneity. To date, more than 30 HCV genotypes have been identified worldwide. Furthermore, HCV may show quasispecies distribution in an infected individual. These findings may have important implications in diagnosis, pathogenesis, treatment, and vaccine development. The hypervariable region 1 found within the envelope E2 protein was shown to be a major site for the genetic evolution of HCV after the onset of hepatitis, and might be involved in escape from the host immunesurveillance system.
...
PMID:Genome of human hepatitis C virus (HCV): gene organization, sequence diversity, and variation. 1125 51

Hepatitis C virus (HCV), discovered in 1989, is the major causative agent of parenteral non-A, non-B hepatitis worldwide. Following the development of a method of diagnosing HCV infection, it became apparent that HCV frequently causes chronic hepatitis. Persistent infection with HCV is implicated in liver cirrhosis and hepatocellular carcinoma. Current worldwide estimations suggest that more than 170 million people have been infected with HCV, an enveloped positive single-stranded RNA (9.6-kilobases) virus belonging to the Flaviviridae. The HCV genome shows remarkable sequence variation, especially in the hypervariable region 1 of the E2 protein-encoding region, and globally, HCV appears to be distributed with more than 30 genotypes. Complicated "quasispecies" and frequent mutations of viral genomes have also emerged. The HCV genome encodes a large polyprotein precursor of about 3,000 amino acid residues, and this precursor protein is cleaved by the host and viral proteinases to generate at least 10 proteins in the following order: NH2-core-envelope (E1)-E2-p7-nonstructural protein 2 (NS2)-NS3-NS4A-NS4B-NS5A-NS5B-COOH. These viral proteins not only function in viral replication but also affect a variety of cellular functions. Although several explanations have been proposed, the mechanisms of HCV infection and replication in targeted cells, the mechanism of persistent viral infection, and the pathogenesis of hepatic diseases (hepatitis or hepatocellular carcinoma) are all poorly understood. A major reason why these mechanisms remain unclear is the lack of a good experimental HCV replication system. Although several classical trials using cultured cells have been reported, several new, more promising experimental strategies (generations of infectious cDNA clone, replicon, animal models, etc.) are currently being designed and tested, in order to resolve these problems. In addition, new therapies for chronic hepatitis have also been developed. The enormous body of information collected thus far in the field of HCV research is summarized below, and an overview of the current status of HCV molecular virology of HCV is provided.
...
PMID:Molecular virology of hepatitis C virus. 1143 27

Background A new hepatitis-associated RNA virus, belonging to the Flaviviridae, has been recently discovered and called HGV (GBV-C). This virus has been shown to be transmitted parenterally. In this study we examined a group of children born to HCV infected women. Methods Between September 1994 and December 1998, we studied a cohort of 53 pregnant women, aged between 20 and 43 years. They were all HCV Ab and HCV RNA positive, with a diagnosis of chronic hepatitis. One patient was HbsAg positive and 4 patients (pts.) (7.5%) were HIV Ab positive. Anamnestic information revealed that: 28 pts. (52.8%) were IVDUs, 11 pts. (20.8%) had been haemotransfused and 14 pts. (26.4%) had no risk factors. We examined HGV RNA by RT nested PCR, using primers from the 5'UTR of HGV. Anti-HGV antibodies (anti-E2) were detected with an ELISA test using recombinant E2 protein. Ten of the 53 pregnant women (18.9%) were HGV RNA positive (32 other pts., 60.4%, were positive for anti-E2 antibodies). We monitored their children for 18-24 months (with clinicai and haematological controls), looking for HGV RNA, anti-E2 antibodies, HCV RNA and for ALT serum levels. Results Seven (70%) new-bom children proved HGV RNA positive at follow-up; all babies were HCV RNA negative at controls. Four of them were born vaginally; none of them was breast-fed. HGV RNA was first detectable at the 3rd month of life in 3 babies, and all babies were HGV RNA positive at the 6th month of life. Six babies (85.7%) remained positive during the observation period. One baby (14.3%) seroconverted at 10 months, developing anti E-2 antibodies and becoming HGV RNA negative. Four babies (57.1%) maintained normal ALT serum levels during the whole follow-up period, while 3 patients showed a low increase in ALT serum levels. The ALT values normalised at later controls. Conclusions HGV infection shows a very high (70%) rate of vertical transmission but a low and doubtful pathogenicity with asymptomatic evolution in babies. Patients who did not develop anti-E2 antibodies at the 12th month of life remained infected without persistent signs of hepatic failure.
...
PMID:[Evolution of hepatitis G in children with vertically transmitted HGV] 1270 18


<< Previous 1 2 3 Next >>