Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.6.1.2 (alanine aminotransferase)
 26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An enzyme-linked immunosorbent assay (ELISA) was developed by using a synthetic polypeptide (SP) whose sequence was derived from the structural region of hepatitis C virus (HCV). Results of several coded panels of sera obtained from volunteer blood donors and patients with apparent non-A, non-B hepatitis and/or hepatitis B virus used in this ELISA were compared with those of a commercially available first-generation C-100 ELISA (using nonstructural HCV antigens), an experimental second-generation C-200/C-22 ELISA (using both structural and nonstructural HCV antigens), and recombinant immunoblot assays RIBA-I and RIBA-II. In the majority of cases, the results obtained with the HCV-SP ELISA correlated well with those obtained by RIBA-II and C-200/C-22 ELISA. In contrast, many samples that were repeatedly reactive in the C-100 ELISA results were nonreactive with RIBA and HCV-SP ELISA. In addition, HCV-SP detected HCV-specific antibody that appeared within a month of infection and coincided with the earliest increase in alanine aminotransferase. In summary, we have developed an ELISA based on a structural HCV synthetic polypeptide, HCV-SP, that has high specificity and sensitivity and is capable of detecting specific antibodies in the acute phase of HCV infection.
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PMID:Detection of acute hepatitis C virus infection by ELISA using a synthetic peptide comprising a structural epitope. 137 3

The c100 hepatitis C virus (HCV) enzyme-linked immunosorbent assay (ELISA) has been used to screen blood donors to prevent transfusion-associated non-A,non-B hepatitis. This test is not specific, and only about 25 percent of c100 HCV ELISA-positive blood samples appear to transmit hepatitis C. However, the intensity of the ELISA (sample/cutoff ratio [S/C], greater than 2) could identify a subpopulation of donors that are at high risk for transmitting hepatitis. Blood samples from 20,186 volunteer blood donors at a Canadian Red Cross blood transfusion center were screened for antibodies to HCV using the c100 HCV ELISA. Fifty-nine (0.3%) of these donors were repeatably reactive on ELISA. When their samples were tested with the c100 recombinant immunoblot assay (RIBA) and second-generation RIBA (RIBA-2), 26 (44%) and 31 (52%) samples, respectively, were found to be positive. Thirty-three of the 59 ELISA-reactive donors had an S/C greater than 2. Of these 33 donors, 30 (91%) had elevated alanine aminotransferase (ALT), 27 (82%) were RIBA-2 positive, and 22 (67%) had risk factors for hepatitis. In contrast, of the 26 ELISA-reactive donors with S/C less than 2, only 7 (27%) had elevated ALT, and 4 (15%) were RIBA-2 positive and also had high risk factors for hepatitis. Thus, while the HCV ELISA may lack specificity, its intensity can serve to identify a subgroup of donors that are at high risk for transmitting hepatitis.
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PMID:Anti-hepatitis C virus (HCV) screening at a Canadian Red Cross center: significance of a positive c100 HCV enzyme-linked immunosorbent assay. 137 40

Fifty-two patients on regular haemodialysis at our institution were evaluated for the presence of HCV infection. Evaluation included detailed history, clinical examination, and monthly screening for anti-HCV antibody, liver enzymes (ALT, AST), serum iron and ferritin. Also, three-monthly screening for other viral markers, HBV (HBsAg, HBsAb, HBcAb), CMV (IgG and IgM), EBV, and HIV. Anti-HCV antibody was found in 21 patients (40.4%). There was a significant (P less than 0.05) relationship between presence of anti-HCV antibody and proportion of patients who received blood transfusion. During a 12-month follow-up, four (11.4%) patients seroconverted to be Anti-HCV positive while one case (4.8%) seroconverted to be anti-HCV negative. The frequency of elevation of liver enzymes was significantly higher in Anti-HCV positive cases (14/18) than in negative cases (11/28, P = 0.01). Evaluation of liver biopsies of 13 patients showed chronic persistent hepatitis in six and chronic active hepatitis in seven cases. We concluded that hepatitis C is a common problem among chronic haemodialysis patients at our institution; HCV infection is documented in 70% of all clinically diagnosed NANB hepatitis. Presence of anti-HCV antibodies cannot differentiate between active and past infection and cases with early HCV infection can be missed when relying on the mere detection of anti-HCV antibodies.
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PMID:Hepatitis C virus infection in chronic haemodialysis patients, a clinicopathologic study. 128 48

Several studies had been carried out on anti-hepatitis C virus (HCV) prevalence in populations with blood exposure risks and in blood donors. New tests are now available which allow the investigation to extend to other parameters such as antibody type and HCV-RNA. In this study the prevalence of anti-HCV c100-3 and the associated epidemiological, clinical, and virological markers were evaluated in subjects from an urban population located in central Italy. In positive cases the time persistence of HCV-RNA and anti-HCV antibody pattern was studied. For this purpose, sera from 1,484 randomly sampled individuals, aged 30-69 years, collected in 1985 and stored at -80 degrees C were retrospectively tested. The prevalence was 0.87% (i.e., 13 anti-HCV c100-3 positive cases). A significant association was observed with raised alanine transaminase (ALT) levels (P less than 0.001). Paired serum samples from 11 out of the 13 subjects collected in 1985 and 1991 were tested by nested polymerase chain reaction (PCR) using primers from the 5' non-coding region and by 4-RIBA. Concordant RIBA patterns between 1985 and 1991 were observed in the majority of positive paired sera (7/9) as well as for HCV-RNA (6/9). HCV-RNA was present in sera simultaneously positive to both types of antibody or to anti-c100-3 or anti-c22 alone. A wide spectrum of viral and antibody patterns in anti-HCV c100-3 positive sera was observed in this urban population and persisted for at least 6 years.
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PMID:Prevalence of hepatitis C virus antibodies and hepatitis C virus-RNA in an urban population. 137 84

To estimate the prevalence of hepatitis C virus (HCV) infection in dialysis patients, serum anti-HCV antibodies were evaluated in 489 Japanese patients undergoing hemodialysis, and 152 members of the hospital dialysis staff by enzyme-linked immunosorbent assays for anti-C100, anti-KCL-163 (HCV nonstructural protein), and anti-JCC (translation product of the presumptive HCV core gene). Of the 489 hemodialysis patients, 100 (20.4%) were positive for anti-C100, 107 (21.9%) for anti-KCL-163, and 168 cases (34.4%) for anti-JCC. These rates were significantly higher than those for either the hospital staff or the healthy blood donors. Forty-two per cent of the dialysis patients were anti-HCV positive by at least one assay, suggesting that HCV infection is more common among this population than previously thought. Positivity for anti-HCV was related to the duration of hemodialysis. Elevated alanine aminotransferase levels were present in 12.5% of the dialysis patients, 77% of whom were also anti-HCV positive. The positivity rates among the 152 members of the hospital staff were 0.7% for anti-C100, 2.6% for anti-KCL-163, and 8.6% for anti-JCC, with the anti-JCC rate of positivity exceeding that of the healthy blood donors.
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PMID:Prevalence of hepatitis C virus antibodies in hemodialysis patients and dialysis staff. 137 11

The localization of hepatitis C virus-infected hepatocytes in the human liver remains unclear despite the development of a serological assay for the antibody to hepatitis C virus. We studied their localization immunohistochemically with monoclonal antibodies to core, envelope and NS3 antigens of hepatitis C virus. We examined 48 liver biopsy samples from C100-3 antibody-positive patients with chronic liver disease (chronic persistent hepatitis, 5 cases; chronic active hepatitis, 41 cases; cirrhosis, 2 cases) and 12 liver biopsy samples from C100-3 antibody-negative patients with chronic liver disease (type B chronic hepatitis, 8 cases; alcoholic liver disease, 4 cases). In the C100-3 antibody-positive group, positive immunostaining for core antigen, envelope antigen and NS3 antigen was found in 23% (11 of 48), 24% (11 of 45) and 24% (11 of 46), respectively. Negative results were obtained in the C100-3 antibody-negative group. Hepatocytes with positive staining were scattered in the lobules, and they were found in the same regions irrespective of whether the antibody to core antigen, to envelope antigen or to NS3 antigen was used. Each positive cell was strongly stained in the cytoplasm; these decorations disappeared after absorption of the primary antibody with purified antigen. mean ALT levels in the patients with positive immunostaining for core, envelope or NS3 antigen (174.8 +/- 105.7 U/L) tended to be higher than in those with negative immunostaining (142.0 +/- 93.8 U/L). On histological evaluation of liver specimens with a scoring system of the histological activity index, intralobular inflammation and fibrosis had higher scores for samples with positive rather than negative immunostaining (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunohistochemical detection of hepatitis C virus-infected hepatocytes in chronic liver disease with monoclonal antibodies to core, envelope and NS3 regions of the hepatitis C virus genome. 137 9

Hepatitis C virus (HCV) is the most important cause of transfusion-related non-A, non-B hepatitis. It is also thought to be the prime cause of non-transfusion-related or sporadic chronic liver disease. To assess the extent of HCV infection and its significance in this last form, we evaluated the clinical, serological and histological features of 84 consecutive HCV-related patients without a history of blood or blood products transfusion, alcohol or intravenous drug abuse or other known risk factors. Our results indicate that 68 patients (81%) had signs of chronicity, and 33 (39.2%) had superimposed cirrhosis. Serum abnormal alanine aminotransferase and gamma-glutamyltransferase activities represented good predictive markers of liver histological signs of chronicity. The levels of serum gammaglobulins were found to parallel histological severity of liver disease. One or more hepatitis B virus (HBV)-associated markers were present in 52 patients (61.9%). Only 6 (7.1%) were chronic HBV carriers, and 3 of them had signs of active virus replication. These data indicate that HCV plays a major role in the etiology of sporadic chronic liver disease. Its presence is associated with histological forms of chronic liver disease in most patients, who likely represent chronic HCV carriers.
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PMID:Hepatitis-C-virus-related chronic liver disease of sporadic type: clinical, serological and histological features. 137 48

Forty-six patients with chronic hepatitis delta virus infection were followed between 6 and 116 mo (mean = 32.8 mo; median = 24 mo). Nineteen patients (41%) demonstrated clinical courses with episodes of biochemical reactivation (ALT levels greater than or equal to 10 times baseline values [group A]). Twenty-seven patients (59%) had stable clinical courses without biochemical reactivation (group B). Patients in group A were younger than those in group B (30.5 vs. 35.3 yr; p = 0.03), were less likely to be intravenous drug abusers (16% vs. 52%; p = 0.01) and were more likely to be homosexual (58% vs. 22%; p = 0.01). Serum hepatitis B virus DNA, hepatitis delta virus RNA, IgM antibody to HBc, HBeAg, antibody to HBe and IgG and IgM antibody to hepatitis delta virus were measured in all patients. In group A, these markers were studied before and during reactivation and during remission. In group B, these parameters were studied in a random fashion at 7- to 10-mo intervals. The presence of antibodies to human immunodeficiency virus and hepatitis C virus was assessed in all patients. A total of 38 biochemical reactivation episodes was noted among the 19 patients in group A. Eleven had sequential changes in hepatitis delta virus markers, suggesting that the exacerbations were due to hepatitis delta virus. In three, the sequential changes of viral markers were consistent with the exacerbations due to hepatitis B virus. In five other patients, no sequential changes in viral markers could be demonstrated to correlate with the biochemical exacerbations.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Spontaneous exacerbation of disease activity in patients with chronic delta hepatitis infection: the role of hepatitis B, C or D? 138 Apr 78

To evaluate the role of IgM specific antibody in the diagnosis and monitoring of the patients with chronic hepatitis C, sera from 114 cases with chronic hepatitis C and liver cirrhosis were tested. IgM antibody to hepatitis C virus was detected in 40.0% of CAH, as compared with 21.4% of CIH, 17.4% of LC, 20.0% of LC with HCC. IgM antibody was also detectable in cases with high level of s-ALT. Patients with positive this antibody have high titer of IgG antibody to hepatitis C virus. In summary, testing for this antibody may be useful to evaluate the recurrence or disease activity and may also be helpful in IFN therapy.
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PMID:[IgM HCV antibody in chronic hepatitis and liver cirrhosis]. 138 May 70

In order to elucidate the relation between hepatitis C virus (HCV) RNA and antibody to HCV (anti-HCV) in serum, we examined samples of serum collected from 228 HBsAg-negative patients, with abnormal alanine aminotransferase (ALT) values, for HCV-RNA by nested polymerase chain reaction (PCR) assay and for anti-HCV using C100 protein as the antigen. HCV-RNA was detected in 99 (92.5%) of 107 anti-HCV-IgG-positive samples, regardless of ELISA optical density cut-off value (ELISA ratio), and in 34 (28.1%) of 121 anti-HCV-IgG-negative samples in which the frequency of the presence of HCV-RNA became higher in proportion to the ELISA ratio. Among 42 discordant cases (34 anti-HCV-IgG-negative, RNA-positive cases and eight anti-HCV-IgG-positive, RNA-negative cases), 10 were positive for anti-HCV-IgM (8/34 and 2/8, respectively) irrespective of clinical status. These findings suggest that in patients with abnormal ALT values, even if they are anti-HCV-IgG negative, HCV infection cannot be excluded. Furthermore, PCR assay for detecting HCV-RNA may be more suitable for identifying patients with infectious virus than is detection of anti-HCV-IgG. Detection of anti-HCV-IgM may also be useful.
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PMID:Hepatitis C virus RNA and hepatitis C virus antibody in the serum of patients with abnormal liver function. 138 35


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