Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The promoter region from the cloned glyceraldehyde-3-phosphate dehydrogenase (GPD) gene of Saccharomyces cerevisiae (Musti et al., 1983) has been characterized. A 653-bp TaqI restriction fragment with a 3' border 24 bp upstream from the ATG initiation codon was isolated and demonstrated to contain all sequences necessary for promoter function in vivo. This DNA segment was converted to a portable promoter by cloning it into M13mp9, and the entire nucleotide sequence of the portable promoter was determined. Two generalized yeast expression vectors have been constructed utilizing the GPD portable promoter. The expression vectors include the yeast 2 mu origin of replication and amplification functions, such that the plasmids are maintained at high copy number in ciro yeast hosts. These vectors direct synthesis of a consensus alpha-interferon (IFN-alpha Con1) as 1% of total cell protein. Hepatitis B surface antigen (HBsAg) was also expressed from these vectors. The 5' end of the HBsAg gene was replaced with a synthetic DNA segment which restored the deleted GPD untranslated leader and utilized optimal yeast codons for the first 30 amino acids. The partially synthetic gene resulted in a 10- to 15-fold increased expression level from GPD vectors yielding HBsAg polypeptide as 2-4% of total cell protein.
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PMID:Expression of heterologous genes in Saccharomyces cerevisiae from vectors utilizing the glyceraldehyde-3-phosphate dehydrogenase gene promoter. 609 18

Ten young adult patients with chronic hepatitis B virus infection and positive hepatitis B e antigen and DNA polymerase (DNAP) levels were treated with alternating courses of seven to 28 days of 5 to 7.5 mg/kg of vidarabine monophosphate (adenine arabinoside monophosphate) and 28 days of human leukocyte interferon (IFN-alpha); three different regimens were given on an outpatient basis. All patients with a fall in their DNAP level, and the DNAP remained undetectable six months after treatment was stopped in one patient. The major side effect, which most often occurred in those patients receiving 7.5 mg/kg of vidarabine monophosphate, was severe muscular pains. This study demonstrated the feasibility of administering vidarabine monophosphate and interferon to outpatients. Based on data from this and other studies, it is now possible to use a relatively nontoxic regimen that includes 28 days of 5 mg/kg of vidarabine monophosphate in a larger controlled study to answer the question of efficacy.
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PMID:Vidarabine monophosphate and human leukocyte interferon in chronic hepatitis B infection. 617 74

The human hepatoma cell line, PLC/PRF/5, which is persistently infected with hepatitis B virus (HBV), has integrated HBV-DNA, secretes HBV surface antigen (HBsAg), and does not grow readily in congenitally athymic (nu/nu) mice. The present investigation was undertaken to ascertain whether the low tumorigenicity of this cell line was governed by a host immune response and/or was related to expression of HBsAg. Subcutaneous injection of 4-5 X 10(6) cells into BALB/c nude mice produced localized encapsulated tumors with morphologic features of primary hepatocellular carcinoma in 25% of the animals within 29-40 d. No tumor growth was observed at lower cell inocula. In contrast, SK-HEP-1, an HBV-negative human hepatoma cell line, produced tumors at 1-5 X 10(6) cells inocula in 66% of the animals. Immunosuppression of mice with antilymphocyte serum (ALS) or irradiation increased tumor incidence in mice inoculated with 1 X 10(6) PLC/PRF/5 cells to almost 100% and produced local invasiveness. Immunosuppression also reduced the latency, i.e., time to tumor appearance, and increased mean tumor weight. These results suggest that tumorigenicity was limited by the host immune response. The nature of the response was delineated by treating nude mice challenged with tumor cells with sheep anti-mouse interferon globulin (anti-IFN). When 2 X 10(6) cells were injected, tumor growth occurred in 75% of anti-IFN-treated mice, whereas controls injected with the same number of cells, but not receiving anti-IFN, failed to develop tumors. The tumors in the anti-IFN-treated mice were highly invasive and the latency period until tumor appearance was reduced to 3-5 d. An inverse correlation was found between susceptibility of the hepatoma cells to natural killer (NK) activity in vitro and resistance to tumor growth in vivo. In vitro cytotoxicity for PLC/PRF/5 cells was eliminated by anti-NK 1.1 and complement, establishing the effector cell as an NK cell. NK cell activity 14 d after inoculation of mice with PLC/PRF/5 cells was augmented against PLC/PRF/5 target cells but not against SK-HEP-1 cells. Treatment of mice with ALS, irradiation, or anti-IFN abolished NK activity against PLC/PRF/5 cells. Co-cultivation of nude mouse spleen cells with PLC/PRF/5 but not with HBsAg or SK-HEP-1 cells induced secretion of murine IFNalpha. These results suggest that the IFN/NK cell system may play a role in limiting tumorigenicity and invasiveness of HBV-infected human hepatocellular carcinoma cells by a mechanism similar to that found for other cells persistently infected with viruses.
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PMID:Role in nude mice of interferon and natural killer cells in inhibiting the tumorigenicity of human hepatocellular carcinoma cells infected with hepatitis B virus. 619 49

Variations in the serum levels of hepatitis C virus (HCV) RNA. IgM antibody against the HCV 'core' structural protein (c22) and alanine amino-transferase (ALT) were measured in 23 patients with chronic hepatitis C who underwent therapy with interferon-alpha 2a (IFN alpha 2a). Low pretreatment levels of viraemia and undetectable IgM anti-core were significantly associated with a long-term response to treatment. In patients with hepatitis relapses after the end of treatment, HCV RNA levels increased before or at the same time as ALT in 29 out of 34 cases (85%). ALT flares occurred before or simultaneously with IgM anti-core elevations in 18 out of 20 cases (90%). Therefore, post-treatment hepatitis C exacerbations show the same sequence of events seen as in hepatitis B exacerbations (increases of viraemia followed by those of ALT and IgM anti-'core'). These findings underscore the diagnostic and prognostic usefulness of monitoring anti-HCV-positive patients with quantitative assays for HCV markers.
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PMID:The fluctuations of hepatitis C virus RNA and IgM anti-HCV (core) serum levels correlate with those of alanine aminotransferases during the hepatitis relapses of patients treated with interferon. 748 43

Chronic coinfection with the hepatitis B (HBV) and hepatitis delta (HDV) viruses is known to cause severe liver disease, but the importance of coinfection with hepatitis C virus (HCV) and HBV has not been well documented. In the present study, the clinical and pathological severity of liver disease among patients with hepatitis resulting from multiple viruses was examined and an open trial of the efficacy of interferon-alpha 2b (IFN-alpha) treatment was conducted. Nineteen patients with chronic HBV and HCV infection and 17 with HBV, HCV and HDV infection were studied; 12 in each group underwent liver biopsy. For each coinfected patient, two patients infected with HCV alone were selected as controls, and these were matched for age and risk factor and were estimated to have been infected for a similar duration. Coinfection with HBV and HCV or HBV, HCV and HDV was associated with more severe liver disease than HCV alone (P < 0.01); total Scheuer score, portal and lobular inflammation and fibrosis were all worse in coinfected subjects. Eight patients with chronic HBV and HCV were treated with recombinant IFN-alpha 2b [3 million units (MU), thrice weekly for 6 months]. Liver function tests normalized in two patients and one lost hepatitis B surface antigen (HBsAg). Seven patients with hepatitis B, C and delta coinfection were treated with the same regimen and only one normalized serum alanine aminotransferase (ALT) during (and after) treatment. It is concluded that coinfection with multiple hepatitis viruses is associated with histologically more severe liver disease than HCV alone.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Coinfection with hepatitis B and C or B, C and delta viruses results in severe chronic liver disease and responds poorly to interferon-alpha treatment. 749 93

Three main patterns of response are seen when interferon-alpha (IFN-alpha) is used for the treatment of chronic hepatitis C: 1 sustained response with alanine-aminotransferase (ALT) normalization that is maintained after cessation of therapy, with or without clearance of serum hepatitis C virus (HCV) RNA; 2 transient response with ALT normalization during therapy followed by relapse after its withdrawal, and 3 no response with no or only partial reduction in ALT levels. In order to define variables that could predict each of these three types of response we studied 321 cases of chronic hepatitis C treated with IFN-alpha in two consecutive trials conducted in our Unit. By univariate analysis, age < 45 years (P < 0.01), known disease duration < 60 months (P < 0.01), normal gamma-glutamyl-transpeptidase (gamma GT) levels (P < 0.01) and infection by HCV genotype 2 or HCV genotype 3 (P < 0.01) were found to be statistically associated with sustained response while age > 45 years (P < 0.01), body weight (P = 0.05), cirrhosis (P < 0.01) and elevated gamma GT levels (P < 0.01) were associated with no response. By multivariate analysis sustained response was predicted by HCV genotype 2 (P < 0.01) and HCV genotype 3 (P < 0.01), known disease duration (P < 0.01), patient's age (P < 0.05) and associated with the use of a more aggressive treatment schedule (P < 0.05). Transient response with relapse was predicted by known duration of disease (P < 0.05), HCV genotype 1 (P < 0.05) and female sex (P < 0.05). No response was statistically associated with elevated gamma GT levels (P < 0.01), higher body weight (P < 0.05) and with the less aggressive regimen of 3 MU of natural IFN-alpha given three times weekly for 6 months (P < 0.05). These results indicate that the HCV genotype as well as the schedule of treatment greatly affect the pattern of response to IFN in chronic hepatitis C and allow us to define criteria to predict which type of response is more likely in individual patients.
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PMID:Predictors of sustained response, relapse and no response in patients with chronic hepatitis C treated with interferon-alpha. 749 3

The advent of specific antiviral therapy for chronic hepatitis C has increased the importance of establishing the correct etiology of chronic hepatitis in patients, especially because interferon alfa (IFN-alpha) has been reported to exacerbate autoimmune hepatitis (AIH), whereas corticosteroids increase viral replication in chronic hepatitis C. In our medical center, we have treated many patients with apparent chronic hepatitis C and serological or clinical evidence of autoimmunity. Our aim was to estimate the prevalence of this association and to learn whether demographic or clinical features distinguished between patients with or without autoimmune markers. We performed a retrospective review of the records of 244 unselected patients seen at the Clinics and Hospital of the University of Massachusetts between May 1991 and November 1993, who had elevated serum aminotransferases. One hundred seventeen patients had chronic hepatitis C defined by elevations of serum alanine transaminase (ALT) for at least 6 months, positive serum antibodies to hepatitis C virus (HCV; second-generation enzyme immunoassay [EIA2] or recombinant immunoblot assay [RIBA]), and absence of hepatitis B surface antigen in the serum. Records were reviewed for results of autoimmune markers in sera, including anti-nuclear antibodies (ANAs), anti-smooth muscle antibodies (SMAs), rheumatoid factor (RF), antimitochondrial antibodies (AMAs), anti-liver and kidney microsomal (LKM) antibodies, and cryoglobulins. We found a high prevalence of positivity, particularly for anti-SMAs (66%) and RF (76%) in both men and women. Forty of 41 patients tested negative for anti-LKM antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:High prevalence of serological markers of autoimmunity in patients with chronic hepatitis C. 753 20

Intensive multidrug chemotherapy with concomitant IFN was performed in three hepatitis B virus (HBV) carriers with malignant lymphomas. All of the patients were HBsAg+, HBsAb-, HBcAb+, HBeAg- and HBeAb+ (mutant strain+). HBV-DNA polymerase (DNA-P) was normal at the beginning of chemotherapy, and complete response was achieved with CO-BLAM chemotherapy (without PDN) in all cases. In case 1, a slight elevation of DNA-P and normal GOT and GPT was observed after IFN-alpha was started during the third course. IFN-alpha was administered twice a week. In case 2, elevation of DNA-P and normal GOT and GTP were noted at the end of the 5th course, then daily IFN-alpha was started. In case 3, daily IFN-alpha was started during the 3rd course because of elevation of DNA-P. It was possible to prevent severe liver damage by administering IFN immediately after the elevation of DNA-P, since DNA-P elevation is noted before GOT and GPT elevation. The detection of the HBV mutant strain could be helpful in the treatment of HBsAg+ and HBeAb+ patients. In all of three patients, DNA-P, serum GOT and GPT normalized quickly after the administration of IFN-alpha. Severe hepatitis did not develop.
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PMID:[Chemotherapy with concomitant IFN treatment in three HBV carriers (mutant strain) with malignant lymphoma]. 756 13

We studied the prevalence of long-term responders to interferon-alpha (IFN-alpha) treatment (undetectable levels of serum IgM anti-HBc, HBV-DNA and normal ALT values for 3 years) in 53 anti-HBe-positive chronic hepatitis B patients. Forty-two of them were treated with (6-18 MU) alpha-2a-recombinant-IFN t.w. for 4-6 months, and the remaining 11 with 10 MU of lymphoblastoid-IFN thrice weekly for 6 months. At the end of treatment, HBV-DNA levels were undetectable and ALT values within the normal range in 34 of 53 patients (60%); IgM anti-HBc levels decreased in all the 34 patients, falling below 10 PEI U in 2/34 (6%). Response to treatment was maintained throughout the follow-up (mean 3 years, range 2-7 years) in five patients (9.4%). The remaining 29 patients experienced HBV reactivation within median follow-up of 6 months (range 1-22 months; 90% of cases within 12 months). Overall 4/9 long-term responders (44.4%) cleared serum HBsAg. In conclusion, chronic anti-HBe-positive hepatitis B has a lower IFN treatment response rate than the HBeAg-positive form; however, among long-term responders, the incidence of serum HBsAg clearance is comparable in the two forms. Because of the high rate of relapses, stringent monitoring criteria (HBV-DNA, IgM anti-HBc and ALT monthly tested for at least 12 months) are mandatory.
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PMID:Treatment of chronic anti-HBe-positive hepatitis B with interferon-alpha. 760 75

Most patients with chronic hepatitis B do not respond to a 4-month course of interferon alpha (IFN-alpha) and require alternative therapy. This paper focuses on alternative treatments for patients who are resistant to conventional IFN regimens (primary nonresponders) and those in whom therapy presents a special challenge. Problem patients include healthy hepatitis B surface antigen (HBsAg) carriers and those with minimal serum aminotransferase elevations, immunosuppressed patients, and patients with end-stage liver disease. Special emphasis is given to patients with decompensated liver disease. While dramatic responses to IFN-alpha can occasionally occur in these patients, serious side-effects are common.
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PMID:Chronic hepatitis B: problem patients (including patients with decompensated disease). 760 76


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