| ah receptor mediating induction of cytochrome p450ia1 in a novel continuous human liver cell line (mz-hep-1). detection by binding with [3h]2,3,7,8-tetrachlorodibenzo-p-dioxin and relationship to the activity of aryl hydrocarbon hydroxylase. | the ah receptor regulates induction of cytochrome p450ia1 and mediates certain toxicities of polyhalogenated aromatics such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd). it has been characterized previously in continuous cell lines, notably the mouse hepatoma line hepa 1, the human squamous cell carcinoma line a431, and the human liver cell line hep g2. the present work extends our knowledge of the ah receptor in continuous human liver cell lines. ah receptor can be detected in mz-hep-1, a hepa ... | 1991 | 1650214 |
| viruses and cancer. | the fact that viruses can cause cancer in animals has been appreciated since the turn of the century. the widely held belief that viruses had little to do with cancer in humans has only recently been dispelled. two classes of human retrovirus (htlv and hiv) have been discovered in the last decade and the malignant potential of hepatitis b virus, epstein barr virus and the human papilloma virus have been documented not only by confirming their association with disease by large scale epidemologica ... | 1991 | 1650623 |
| [hepatitis b virus and hepatocellular carcinoma]. | hepatocellular carcinomas in woodchuck were characterized for woodchuck hepatitis virus integration near c-myc oncogene. in one tumor, viral integration resulted in overexpression of a c-myc viral cotranscript. in a second tumor, viral insertion, 600 bp upstream of c-myc exon 1, was associated with increased levels of normal c-myc mrna. these results demonstrate that integration of woodchuck hepatitis virus near a proto-oncogene can contribute to the genesis of liver tumors. from a comparison of ... | 1991 | 1650625 |
| from the centers for disease control. recommendations for preventing transmission of human immunodeficiency virus, hepatitis b virus to patients during exposure-prone invasive procedures. | | 1991 | 1650847 |
| update on human immunodeficiency virus (hiv) and hepatitis b virus (hbv). transmission of human immunodeficiency virus to patients. | | 1991 | 1651117 |
| complex regulation of transcription from the hepatitis b virus major surface antigen promoter in human hepatoma cell lines. | a detailed mutational analysis of the regulatory dna sequence elements that control expression of the hepatitis b virus major surface antigen gene was performed in the human hepatoma cell lines hepg2.1 and huh7, using transient transfection assays. seven regions (a to g) of the major surface antigen promoter located within 200 nucleotides of the rna initiation site have been identified which influence the level of transcription from this promoter. the three distal regions (a to c), located betwe ... | 1991 | 1651407 |
| preferential expression of the large hepatitis b virus surface antigen gene by an adenovirus-hepatitis b virus recombinant. | using an adenovirus-hepatitis b virus (hbv) recombinant, expression of the hbv surface antigen (hbsag) genes was examined in various cell lines using s1 nuclease mapping and radioimmunoassay. the steady-state level of the 2.4 kb rna encoding the large hbsag was much greater than, or the same as, that of the 2.0 kb rna, encoding the middle and major hbsags, in primate cells, but was negligible in non-primate cells, as is the case in most expression systems. according to the amount of 2.4 kb rna e ... | 1991 | 1651985 |
| a bacteriophage m13 based sandwich hybridization assay for the detection of hepatitis b virus in human blood. | a two step hybridization procedure was developed to detect the presence of hepatitis b virus in blood samples using bacteriophage m13 radiolabelled dna as probe. during the first step of hybridization, single-stranded bacteriophage m13 tg 130 dna, with 3.2 kb hbv dna cloned into it, was hybridized to target hbv dna immobilized on nitrocellulose membrane filter. in the second step of hybridization, m13 dna annealed to hbv target is detected with the help of double stranded form of m13 dna. the as ... | 1991 | 1652551 |
| [pathogenesis of human cancer]. | the multistep aspects of carcinogenesis including initiation and promotion problems in both human and experimental hepatocarcinogenesis are discussed, especially in terms of oncogene and antioncogene changes. it is shown that the h-ras activation may be an event occurring in relatively late phase of carcinogenesis in the mouse systems, and that hepatitis b integration frequently causes host chromosomal rearrangement possibly leading to inactivation of cancer suppressor genes. in addition, signif ... | 1991 | 1653595 |
| [hbv status and expression of ets-2, igf-ii, c-myc and n-ras in human hepatocellular carcinoma and adjacent nontumorous tissues--a comparative study]. | a comparative study on hbv status and ets-2, igf-ii, c-myc and n-ras expression in 12 pairs of human primary hepatocellular carcinoma (phc) and adjacent non-tumorous tissues (nt) showed that integrated forms of hbv dna were present in 91.5% phc and 75% nt. no specific integration sites were detected. three phc and 4 nt were found to have free forms of hbv dna, which were defective in 2 phc and 3 nt, i. e., being able to replicate but not to be secreted into the blood. at least one of four oncoge ... | 1991 | 1653692 |
| prevalence of antibodies to human herpesviruses and hepatitis b virus in patients at different stages of human immunodeficiency virus (hiv) infection. | the results of antibody assays for viruses of the herpes group (hsv, ebv, vzv and cmv) and for hepatitis b virus (hbv) were retrospectively evaluated in 439 hiv-seropositive patients classified into different stages of hiv infection. the prevalence of specific igg, igm and iga antibodies in these groups was compared with that of a control group of hiv-negative unselected hospital patients. antibodies to herpes viruses and hbv were more prevalent amongst hiv-seropositives, especially las and aids ... | 1991 | 1653770 |
| in vivo expression of il-1 beta and il-6 genes during viral infections in human. | macrophage infiltration is a constant feature of human virus-infected tissues. however, the in situ functional status of these cells remains undetermined. in order to document an activation of macrophages in virus-infected tissues, the expression of il-1 beta and il-6 genes was analyzed using in situ hybridization. several tissues were studied, as well as infections induced by different viruses: lymph nodes infected by hiv-1 (9 cases) or ebv (one case), lungs infected by cmv (5 cases) or adenovi ... | 1991 | 1654144 |
| leukotriene and prostaglandin production after infusion of tumour necrosis factor in man. | tumor necrosis factor-alpha is believed to be an important mediator of endotoxaemia and septic shock, the effects of which are thought to be mediated through the generation of cysteinyl-leukotrienes, thromboxane a2 and other prostanoids. we have investigated the production of these eicosanoids and also that of prostacyclin in vivo after infusion of tumor necrosis factor-alpha into 4 subjects with a chronic hepatitis b virus infection. this resulted in plasma tnf levels considerably greater than ... | 1991 | 1654958 |
| clustering of hepatocellular carcinoma in alaska native families. | alaska natives have a high incidence of hepatocellular carcinoma (hcc), with regional, ethnic, village, and familial clustering. during 1969-1988, 15 of the 45 incident cases of hcc in alaska natives occurred in 5 families. this report presents epidemiologic, virologic, and immunogenetic data on these 5 families. the results of hepatitis b virus (hbv) serologic testing indicates that hbv infection was an important factor in 4 of the 5 families. human lymphocyte antigen (hla) testing was performe ... | 1991 | 1655562 |
| promoter-specific transactivation of hepatitis b virus transcription by a glutamine- and proline-rich domain of hepatocyte nuclear factor 1. | the cloned transcription factor hepatocyte nuclear factor 1 (hnf1) transactivates transcription from the hepatitis b virus (hbv) large surface antigen promoter but does not influence the transcriptional activities of the other three hbv promoters. this indicates that this transcription factor can differentially influence the activities of the hbv promoter. by using a transient-transfection system, the major domain of the hnf1 polypeptide involved in transcriptional activation of the large surfac ... | 1991 | 1656070 |
| inhibition of the replication of hepatitis b virus in vitro by 2',3'-dideoxy-3'-thiacytidine and related analogues. | several 2',3'-dideoxy-3'-thiapyrimidine nucleosides were studied for their ability to inhibit hepatitis b virus (hbv) dna replication in a hbv-transfected cell line (2.2.15). 2',3'-dideoxy-3'-thiacytidine (sddc) and 5-fluoro-2',3'-dideoxy-3'-thiacytidine(5-fsddc) were found to be the most potent anti-hbv compounds of those examined. both compounds resulted in nearly complete cessation of viral dna replication at 0.5 microm, as monitored by the absence of both intracellular episomal and secreted ... | 1991 | 1656445 |
| evidence for increased in vitro recombination with insertion of human hepatitis b virus dna. | chromosomal translocation, deletion, and inversion/duplication directly linked to hepatitis b virus (hbv) dna integration occur frequently in host dna of human hepatocellular carcinomas. to test the possible recombinogenic effect of hbv dna, we have utilized an in vitro recombination assay. fragments containing the region spanning dr1, which is believed to be the origin of viral replication and a preferred site in the viral genome for integration, increased the recombination events reproducibly ... | 1991 | 1656466 |
| production of 22 nm hbsag particles by human lymphocytes infected with a recombinant vaccinia virus containing the coding sequence for hepatitis b virus surface antigen. | to examine the possible role of lymphocytes in the course of hepatitis b virus infection, we studied peripheral blood lymphocytes and epstein-barr virus transformed b-cells for their capability to produce hepatitis b virus gene products. infection of these cells with a recombinant vaccinia virus containing the hepatitis b virus surface antigen resulted in the production and secretion of hepatitis b virus surface antigen shortly after infection reaching a peak after three days. when the supernata ... | 1991 | 1656954 |
| the application of ampliprobe in diagnostics. | ampliprobe system is a rapid, enzyme-labeled, non-isotopic probe system that has high sensitivity and flexibility. ampliprobe system consists of two major components: target-specific "primary" probes and target-independent, enzyme-labeled, signal-generating "secondary" probes. the visualization of the complemental hybridization between the target dna or rna and probes is accomplished by an enzymatic chemiluminescent reaction. the ampliprobe system format allows hybridization and signal visualiza ... | 1991 | 1657053 |
| prevalence of antibodies to hepatitis c virus (anti-hcv) in different populations in taiwan. | the prevalence of antibodies to hepatitis c virus (anti-hcv) was investigated among different populations in taiwan, where anti-hcv was detected in 0.8% (24/2,994) of adult volunteer blood donors, 0.1% (1/1,305) of youngsters and children, 12.5% (8/64) of adult volunteer blood donors with elevated alanine aminotransferase (alt), 36.5% (23/63) of hemodialysis patients, 4.1% (13/318) of male homosexuals, 25.4% (16/63) of cases positive for antibodies to human immunodeficiency virus (anti-hiv), 82. ... | 1991 | 1657545 |
| failure to detect hepatitis c virus genome in human secretions with the polymerase chain reaction. | although hepatitis c infection has been clearly demonstrated to be transmitted through blood products or blood contamination, most cases of sporadic hepatitis c infection are unassociated with parenteral risk factors, and it is unclear how infection might be acquired by nonparenteral means. one potential mode of nonparenteral transmission is through body secretions. we used a highly sensitive and specific polymerase chain reaction assay to determine whether hepatitis c viral genomic rna could be ... | 1991 | 1657752 |
| random association between the peptide repertoire of a2.1 class i and several different dr class ii molecules. | the interaction between synthetic peptides and a2.1 class i mhc molecules has been investigated using an inhibition of ag presentation assay and unbiased peptide sets derived of either viral or eucaryotic origin. for the various sets, strong binding (defined as significant inhibition at the 30 micrograms/ml level) was detected in 7 to 46% of the peptides tested, with an overall frequency of 26%. a set of self-peptides derived from human beta 2 microglobulin was also included in the study. in thi ... | 1991 | 1658152 |
| small-form hepatitis b surface antigen is sufficient to help in the assembly of hepatitis delta virus-like particles. | hepatitis delta virus (hdv) has an envelope composed of large-, middle-, and small-form hepatitis b surface antigens (hbsags) provided by the helper hepatitis b virus (hbv). in order to examine the roles of individual hbsags in hdv assembly, we constructed plasmids containing each specific hbsag gene and then cotransfected each plasmid with hdv cdna into a permissive human hepatoma cell line (huh-7) to examine the effects on hdv production. results indicated that the plasmids containing only the ... | 1991 | 1658366 |
| antibodies to cytomegalovirus, herpes simplex virus and epstein-barr virus in greek blood donors. | an epidemiological study for detection of igg and igm antibodies against cytomegalovirus, epstein-barr virus and herpes simplex virus was evaluated in a random population of apparently healthy greek blood donors from which only hiv and hbv carriers were excluded. the prevalence of igm antibodies was found to be relatively low at 4.4%, 6.1% and 7.7% respectively. the presence of these antibodies plays an important role when transfusing immunocompromised and transplanted subjects. | 1991 | 1658527 |
| recommendations for preventing transmission of human immunodeficiency virus and hepatitis b virus to patients during exposure-prone invasive procedures. | this document has been developed by the centers for disease control (cdc) to update recommendations for prevention of transmission of human immunodeficiency virus (hiv) and hepatitis b virus (hbv) in the health-care setting. current data suggest that the risk for such transmission from a health-care worker (hcw) to a patient during an invasive procedure is small; a precise assessment of the risk is not yet available. this document contains recommendations to provide guidance for prevention of hi ... | 1991 | 1659315 |
| viruses in human cancers. | viruses may contribute to the development of human tumors by different mechanisms: indirectly by inducing immunosuppression or by modifying the host cell genome without persistence of viral dna; directly by inducing oncoproteins or by altering the expression of host cell proteins at the site of viral dna integration. human cancers associated with papillomavirus, hepatitis b virus, epstein-barr virus, and human t cell leukemia-lymphoma virus infections are responsible for approximately 15 percent ... | 1991 | 1659743 |
| hla class i-restricted human cytotoxic t cells recognize endogenously synthesized hepatitis b virus nucleocapsid antigen. | knowledge of the immune effector mechanisms responsible for clearance of hepatitis b virus (hbv)-infected cells has been severely limited by the absence of reproducible systems to selectively expand and to characterize hbv-specific cytotoxic t lymphocytes (ctls) in the peripheral blood of patients with viral hepatitis. by using a strategy involving sequential stimulation with hbv nucleocapsid synthetic peptides followed by autologous, or hla class i-matched, hbv nucleocapsid transfectants, we no ... | 1991 | 1660137 |
| hepatocellular carcinoma: risk factors other than hbv. | the putative risk factors for hepatocellular carcinoma (hcc) are several, even in countries endemic for hepatitis b virus (hbv) infection. cirrhosis characterizes more than 90% of hcc cases. the phases of inflammation, necrosis and regeneration, present for long periods in cirrhosis, might be most relevant in hepatocarcinogenesis. it is not clear what role is played by sex hormones while alcohol probably has a promoter role. aflatoxins are known carcinogenins in the experimental animal: however ... | 1991 | 1660333 |
| does hepatitis b virus play a role in primary liver cancer in children of western countries? | hepatitis b virus (hbv) infection was evaluated in serum and liver specimens of eight italian children with primary liver cancer. all children were negative for hbv markers in serum but four of them showed hbv-dna sequences and/or hbs antigen expression in the liver. in one case, viral dna was present in both neoplastic and non-neoplastic tissue, while in one case hbv-dna was detectable only in nontumoral tissue and in one case only in the tumor area. in these cases, scattered hbsag was expresse ... | 1991 | 1661202 |
| heterosexual and homosexual transmission of hepatitis c virus: relation with hepatitis b virus and human immunodeficiency virus type 1. | a seroprevalence study was carried out on 1757 outpatients consecutively seen in a sexually transmitted disease (std) clinic in order to evaluate the sexual transmission of hepatitis c virus (hcv). a total of 1442 consenting patients were tested for hepatitis c, hepatitis b and human immunodeficiency virus type 1 (hcv, hbv, hiv-1) antibodies. the relations between anti-hcv, anti-hbc and anti-hiv-1 were studied. of 73 anti-hcv positive reactions, 45 (61.6%) were confirmed by the recombinant immun ... | 1991 | 1661241 |
| proto-oncogene expression in three human hepatoma cell lines, hcc-m, hcc-t and plc/prf/5. | changes of nucleotide sequences and expressions of cellular oncogenes in human hepatoma cell lines, plc/prf/5, hcc-m and hcc-t cells, were examined by southern and northern blot analyses. the probes used are dna fragment of myc, n-, h-, k-ras, fos, fms, raf, erb-a, erb-b, and erb-b2 genes and synthetic oligonucleotides corresponding to the part of n-, h-, k-ras genes. the results are as follows. dna amplification and rearrangement were not detected in these three human hepatoma cell lines. point ... | 1991 | 1661347 |
| immunovirology of transforming viruses. | the paradigmatic shift in cellular immunology, initiated by the realization that cytotoxic t lymphocytes recognize major histocompatibility complex class i antigens that carry endogenous (including virally encoded) protein-derived peptides in a special groove, has made a strong impact on the immunopathology of virus-associated tumors. | 1991 | 1661601 |
| effects of human lymphoblastoid interferon on proliferation, gene expression and tumourigenicity of human hepatoma cell lines. | hep g2 and hep 3b cells, two human hepatoma cell lines, showed decreased thymidine (thd) incorporation into intracellular acid-insoluble pools when exposed to wellferon, human lymphoblastoid interferon (ifn). inhibition was maximal after 48 h treatment with wellferon and was reversible. significant inhibition in wellferon-treated hep 3b cells was noted at concentrations of 1 ifn unit/ml, which was over 1000-fold less than that required to produce equivalent effects in hep g2 cells. the decrease ... | 1991 | 1663028 |
| cohort study of hepatotropic virus and human t lymphotropic virus type-i infections in an area endemic for adult t cell leukemia. | we tested for antibodies to hepatitis b virus (hbv), hepatitis c virus (hcv), and human t lymphotropic virus type-i (htlv-i) in 629 normal inhabitants of an adult t cell leukemia (atl) endemic area and in patients with atl, htlv-i associated myelopathy (ham), and hepatocellular carcinoma (hcc) from the same district. the prevalence of serological positivity for each virus was 28.0, 6.4, and 32.6%, respectively, among the 629 inhabitants. there was a positive association between the presence of a ... | 1991 | 1665877 |
| a rapid method of sample preparation for detection of dna viruses in human serum by polymerase chain reaction. | a rapid method of serum treatment is described that can be used for the detection of viral dna by polymerase chain reaction (pcr). the key feature of the assay is inactivation of inhibitory serum factors by controlled heating of serum. this method avoids dna extraction. it is very fast and limited sample handling decreases the chances of contamination by exogenous dna. it has been successfully used for demonstration of parvovirus b19, hepatitis b virus, and human cytomegalovirus dna in patient s ... | 1991 | 1666114 |
| a technique for liver biopsy performed in pekin ducks using anesthesia with telazol. | infection of pekin ducks with duck hepatitis b virus is a useful model for studying the hepadenoviruses, of which human hepatitis b virus is the prototype. the utility of this model has been limited, however, by the difficulties associated with anesthetizing and obtaining liver biopsies from ducks. we developed a technique using telazol (13 mg/kg) to anesthetize ducks before surgical biopsy of the liver in ducks infected with duck hepatitis b virus. eight pekin ducks infected with duck hepatitis ... | 1991 | 1666151 |
| infection control in dentistry. | the risk of transmission of infection within the dental workplace is low, but recent data have indicated that human immunodeficiency virus transmission between dentist and patient can occur, and that while nosocomial transmission of hepatitis b virus is now less likely, a small but significant number of staff may be at risk of hepatitis c virus and varicella zoster virus infection during dental treatment. despite these continued risks, shortcomings remain in cross-infection control in the dental ... | 1991 | 1666310 |
| hepatitis-e-virus-associated antigen: improved detection in stools by protein fv removal. | elisa detection of a hepatitis-e-virus-associated antigen (hev-aag) in stools was reappraised for its possible interference with a new fab-binding factor, termed protein fv, released during infectious hepatitis. transaminase elevation, hev-aag discharge and fv leakage appeared simultaneously in a cercopithecus monkey inoculated with infected stools. labelled normal, or immune human igg, were compared with pre- and post-inoculation simian igg, for hev-aag and fv detection. coated normal and patie ... | 1991 | 1666435 |
| recommendations for preventing transmission of human immunodeficiency virus and hepatitis b virus to patients during exposure-prone invasive procedures. | | 1991 | 1667530 |
| branched dna amplification multimers for the sensitive, direct detection of human hepatitis viruses. | branched oligonucleotides (bdna) have been synthesized containing a unique primary segment and a set of identical secondary fragments covalently attached to the primary sequence through branch points. the primary sequence is designed to hybridize (directly or indirectly) to a target nucleic acid, such as hepatitis b virus (hbv) or hepatitis c virus (hcv) genomic dna or rna, respectively. the secondary fragments are used to direct the binding of multiple copies of a small oligonucleotide labelled ... | 1991 | 1668687 |
| viruses and cancer. causal associations. | this review first considered some general problems in establishing causal links between a virus and a human cancer and offered some guidelines in the pursuit of this objective. second, it reviewed the current causal associations for several candidate oncogenic viruses in relation to the tumors with which they are associated. these include epstein-barr virus in relation to burkitt's lymphoma, nasopharyngeal carcinoma, hodgkin's disease, and non-hodgkin's lymphoma; hepatitis b and c viruses in rel ... | 1990 | 1669491 |
| hepatitis b virus integration event in human chromosome 17p near the p53 gene identifies the region of the chromosome commonly deleted in virus-positive hepatocellular carcinomas. | the development of hepatocellular carcinoma (hcc) presumably occurs in multiple steps and is influenced by numerous factors. hepatitis b virus (hbv) is strongly associated with the development of hcc in people chronically infected with the virus, but the mechanism of viral involvement remains unclear. one possibility is that the gross chromosomal alterations frequently observed in hcc dna at the site of hbv integration may alter the expression of important nearby cellular genes. we previously re ... | 1991 | 1670994 |
| allelotype study of primary hepatocellular carcinoma. | accumulation of mutations in oncogenes and tumor suppressor genes transforms a normal cell to a malignant cell by allowing it to escape from normal control of growth. in order to learn (a) how many tumor suppressor genes are involved in the tumor progression of hepatocellular carcinoma, (b) whether there is any association among allelic losses of chromosomes, or (c) whether integration of hepatitis b virus into host dna influences any particular chromosomal losses, we have examined loss of heter ... | 1991 | 1670995 |
| selective g to t mutations of p53 gene in hepatocellular carcinoma from southern africa. | hepatocellular carcinoma (hcc) is a prevalent cancer in sub-saharan africa and eastern asia. hepatitis b virus and aflatoxins are risk factors for hcc, but the molecular mechanism of human hepatocellular carcinogenesis is largely unknown. abnormalities in the structure and expression of the tumour-suppressor gene p53 are frequent in hcc cell lines, and allelic losses from chromosome 17p have been found in hccs from china and japan. here we report on allelic deletions from chromosome 17p and muta ... | 1991 | 1672732 |
| human immunodeficiency virus infection does not alter serum transaminases and hepatitis b virus (hbv) dna in homosexual patients with chronic hbv infection. | the influence of human immunodeficiency virus (hiv) infection on the clinical course of chronic hepatitis b virus (hbv) infection is controversial. we followed a cohort of 64 homosexual men with persistent hbs antigenemia for a median of 24 months in the hepatitis clinic of a large urban public hospital. we divided the patients into three groups according to their immune status. group 1 (n = 13) consisted of hiv-seropositive men with evidence of immunosuppression; group 2 (n = 17), hiv-positive ... | 1991 | 1674196 |
| influence of human immunodeficiency virus infection on cell-mediated immunity in chronic d hepatitis. | to determine whether the abnormalities of cell-mediated immunity described in chronic d hepatitis are associated with hepatitis d virus (hdv) infection or concomitant human immunodeficiency virus (hiv) infection, serologic and tissue hepatitis b virus (hbv) and hdv markers and t lymphocyte subsets were studied in serum samples from 38 patients with chronic d hepatitis, 26 of whom had hiv infection. patients with chronic d hepatitis and hiv infection had significantly lower peripheral blood t4:t8 ... | 1991 | 1674749 |
| [periarteritis nodosa-type vasculitis and infection with human immunodeficiency virus]. | the human immunodeficiency virus (hiv) may be responsible for several types of vasculitis: leucocytoclastic vasculitis, granulomatous angiitis, angiitis associated with lymphoproliferative syndromes or necrotizing vasculitis including periarteritis nodosa (pan). we report a case of pan in a 62-year old hiv1-positive woman. the patient had no co-occurrent hepatitis b virus infection and was negative for antinuclear antibodies. she presented with sicca syndrome, necrotic purpura, myalgias and poly ... | 1991 | 1675017 |
| immunologic correlates of spontaneous lymphocyte proliferation in human t-lymphotropic virus infection. | previously we showed that mononuclear cells from about half of human t-lymphotropic virus (htlv)-seropositive persons exhibit spontaneous proliferation in vitro. we sought to determine if proliferation was associated with other immunologic changes characteristic of htlv infection. the parameters assessed were (1) percentages of lymphocytes expressing cd4 and/or cd25 (interleukin-2 receptor), (2) serum levels of soluble cd25, (3) serostatus for other viruses, (4) anti-htlv antibody levels, and (5 ... | 1991 | 1676916 |
| loss of somatic heterozygosity in hepatocellular carcinoma. | loss of tumor suppressor genes is involved in the mechanism of tumorigenesis of many solid tumors. we tested 9 hepatitis b virus (hbv)-positive and 10 hbv-negative hepatocellular carcinomas for loss of somatic heterozygosity using 14 polymorphic probes mapping to chromosomes 4, 11, 13, and 17. losses were found on all chromosome arms tested. the highest frequency of loss was observed at the d13s1 locus (67%) at band 13q12. losses were also observed at three other loci on 13q. twenty-one % of inf ... | 1991 | 1678314 |
| phlebotomy in inoculation risk patients: a questionnaire survey of knowledge and practices of hospital doctors in liverpool. | to assess the knowledge of hospital doctors about patients at increased risk of infection with human immunodeficiency virus (hiv) or hepatitis b virus, and the precautions they took during phlebotomy in such patients, an anonymous postal questionnaire was sent to all 307 hospital doctors working at two district general hospitals in liverpool, uk. two hundred and thirty-eight (77.5%) of the questionnaires were returned. more than 90% of respondents considered a history of male homosexuality, intr ... | 1991 | 1682370 |
| chromosomal sites for hepatitis b virus integration in human hepatocellular carcinoma. | the discovery that hepatitis b virus (hbv) integrates into host chromosomes raises the question of whether such viral dna integration correlates directly with the activation of specific oncogenes or the inactivation of anti-oncogenes. to obtain insight into this problem, we randomly collected hbv integrant samples from different human hepatocellular carcinomas and identified the site of chromosomal integration by using in situ hybridization and/or linkage analysis with the flanking cellular dnas ... | 1991 | 1682510 |
| hepatitis b virus transmitted via bite. | | 1991 | 1683455 |
| prevalence of hepatitis c virus antibody in an area endemic for hepatitis b virus and human t cell leukaemia virus. | to clarify the prevalence of concurrent infection with hepatitis c virus (hcv), hepatitis b virus (hbv) and human t cell leukaemia virus (htlv), we measured hcv antibody in the population of a district endemic for hbv and htlv infection. blood samples were collected in june 1990 from 579 inhabitants of four islands of uwa bay in the southwest of ehime prefecture in japan. anti-hcv antibody against c100-3 protein was detected using an enzyme-linked immunosorbent assay kit (ortho diagnostics). thi ... | 1991 | 1685926 |
| carcinoembryonic antigen and alpha-fetoprotein expression and monoclonal antibody targeting in a human hepatoma/nude mouse model. | hep g2, a human hepatocellular carcinoma, was grown s.c. in nude mice, as well as in tissue culture. this line retains the normal liver parenchymal cell capacity to synthesize human plasma proteins such as albumin, but there is no indication that it harbors the hepatitis b virus. we have detected the oncofetal antigens alpha-fetoprotein (afp) and carcinoembryonic antigen (cea) in both hep g2 xenografts and spent tissue culture media by ouchterlony double diffusion assays, enzyme-linked immunosor ... | 1990 | 1688735 |
| cis rescue of a mutated reverse transcriptase gene of human hepatitis b virus by creation of an internal atg. | using mutational analysis, we have investigated the translation strategy of the reverse transcriptase gene (pol) of human hepatitis b virus. it has been proposed that this pol gene product is synthesized as a core-pol fusion protein from a polycistronic mrna template via ribosomal frameshifting, a mechanism often seen in retroelements. our data indicate that creation of a novel atg initiation codon near the original atg can compensate for a lethal missense mutation at the first atg position of t ... | 1990 | 1689389 |
| immunogenic domains of hepatitis delta virus antigen: peptide mapping of epitopes recognized by human and woodchuck antibodies. | hepatitis delta virus (hdv) is a defective rna virus which is dependent on hepatitis b virus for essential helper functions. only a single highly basic phosphoprotein, hdv antigen (hdag), is expressed by the hdv genome during infection in humans. antibody directed to hdag is important in the diagnosis of hdv infection, and it is likely but not yet proven that the immune response to hdag provides significant protection against subsequent exposures to hdv. in an effort to map the antigenic domains ... | 1990 | 1689390 |
| c-ha-ras down regulates the alpha-fetoprotein gene but not the albumin gene in human hepatoma cells. | we studied the effects of transfection of the normal c-ha-ras gene, rasgly-12, and its oncogenic mutant, rasval-12, on expression of the alpha-fetoprotein (afp) and albumin genes in a human hepatoma cell line, huh-7. the mutant and, to a lesser extent, the normal ras gene caused reduction of the afp mrna but not the albumin mrna level in transfected huh-7 cells. cotransfection experiments with a rasval-12 expression plasmid and a chloramphenicol acetyltransferase reporter gene fused to afp regul ... | 1990 | 1690841 |
| hepatitis c virus antibodies in southern african blacks with hepatocellular carcinoma. | 380 southern african blacks with hepatocellular carcinoma and 152 controls were studied. antibodies to hepatitis c virus (hcv) were found in 110 patients and 1 control. 184 patients had evidence of current infection with hepatitis b virus (hbv) and 122 had had infection with this virus in the past. only 47 patients had no markers of hcv or hbv infection. among patients positive for hcv, there was a higher proportion of women and urban dwellers, and the average age was higher. in southern africa, ... | 1990 | 1691422 |
| immunobiology and pathogenesis of hepatocellular injury in hepatitis b virus transgenic mice. | the role of the immune response to hepatitis b virus (hbv)-encoded antigens in the pathogenesis of liver cell injury has not been defined because of the absence of appropriate experimental models. hbv envelope transgenic mice were used to show that hbv-encoded antigens are expressed at the hepatocyte surface in a form recognizable by major histocompatibility complex (mhc) class i-restricted, cd8+ cytotoxic t lymphocytes specific for a dominant t cell epitope within the major envelope polypeptide ... | 1990 | 1691527 |
| hepatocarcinogenesis due to chronic liver cell injury in hepatitis b virus transgenic mice. | fifty-nine transgenic mice from a lineage that overproduces the hepatitis b virus large envelope polypeptide and accumulates high intrahepatic concentrations of hepatitis b surface antigen were followed for evidence of liver disease throughout their 24-month life span. by 4 months of age all mice displayed biochemical and histological evidence of moderately severe chronic hepatitis which was followed sequentially by the development of regenerative nodules and oval cell hyperplasia (by 6 months), ... | 1990 | 1692259 |
| mapping of b-cell epitopes of the human hepatitis b virus x protein. | the immune response to the x protein of human hepatitis b virus (hbv) was studied by epitope mapping by using a set of ms2-hbx fusion proteins and synthetic peptides. antibodies in sera of patients with acute and chronic hbv infection showed a multispecific immune response. each serum contained antibodies to a different set of epitopes, which taken together cover most of the hbx sequence. some of the epitopes were detectable only by immunoblotting with fusion proteins; others were detectable onl ... | 1990 | 1692348 |
| immunohistochemical studies of intrahepatic tumour necrosis factor alpha in chronic liver disease. | to determine the intrahepatic production of tumour necrosis factor alpha (tnf alpha) in chronic liver disease three monoclonal antibodies were used against tnf alpha in immunohistochemical studies of liver tissue sections from patients with chronic liver disease. all three monoclonal antibodies stained infiltrating mononuclear cells. monoclonal antibody ii 7c2 also stained the cytoplasm or nucleus, or both, of a varied number of hepatocytes from nine patients with chronic hepatitis b virus infec ... | 1990 | 1692847 |
| alpha-fetoprotein in the woodchuck model of hepadnavirus infection and disease: immunochemical analysis of woodchuck alpha-fetoprotein and measurement in serum by quantitative monoclonal radioimmunoassay. | woodchuck hepatitis virus infection of the eastern woodchuck represents a useful model for the study of hepatitis b virus infection and disease in humans, including hepatocellular carcinoma. in man, hepatocellular carcinoma is frequently detected and monitored using assays for serum alpha-fetoprotein. to study the relationship between alpha-fetoprotein and woodchuck hepatitis virus-induced hepatocellular carcinoma in the woodchuck model, we produced a monoclonal antibody to woodchuck alpha-fetop ... | 1990 | 1693355 |
| stable expression of hepatitis delta virus antigen in a eukaryotic cell line. | the gene encoding the hepatitis delta virus structural antigen (hdag) was linked to a neomycin resistance gene in a retrovirus expression vector, and human hepg2 cells were transfected with the recombinant plasmid. a stable cell line was cloned that expressed hdag in the nuclei of 100% of cells, in a pattern indicating a close relationship with cell nucleoli. analysis of partially purified recombinant hdag by hplc showed an mr in the range of 7 x 10(5) to 2 x 10(6), which appeared to contain con ... | 1990 | 1693665 |
| growth-factor independence of a new differentiated hepatitis b virus dna-negative human hepatoma cell line. | the establishment of a new, differentiated, hepatitis b virus dna-negative, human hepatoma cell line (named plc/an/2) is described. neoplastic liver tissue was obtained during hepatectomy in an hbsag-negative man. the established cell line is negative for alpha-fetoprotein and carcinoembryonic antigen; it has retained in vitro some of the differentiated functions of normal hepatocytes. additionally, it presents a distinctive rearrangement (translocation) at the long arm of chromosome 4. the high ... | 1990 | 1694812 |
| in situ hybridization: application to the study of gene expression during experimental hepatocarcinogenesis and human hepatocellular carcinoma. | the possibility of detecting specific mrna directly within tumor cells offered by the in situ hybridization (ish) technique has provided a new dimension to the study of experimental and human hepatocarcinogenesis. the combination of ish and immunocytochemical techniques on the same or adjacent tissue sections provides a more complete picture of the various changes in gene expression. ish may also detect posttranscriptional abnormalities of gene expression at the cellular level, such as expressio ... | 1990 | 1695388 |
| antiviral strategies in chronic hepatitis b virus infection: ii. inhibition of duck hepatitis b virus in vitro using conventional antiviral agents and supercoiled-dna active compounds. | primary duck hepatocyte (pdh) cultures, congenitally infected with the duck hepatitis b virus (dhbv), were grown on feeder cell layers of irradiated human embryonic lung fibroblasts and then exposed to a number of compounds with recognized or potential antiviral activity. these compounds included conventional antiviral agents, reverse transcriptase inhibitors, compounds with activity to supercoiled-dna, and dna-binding agents. twenty-three compounds were evaluated, and 13 were found to inhibit s ... | 1990 | 1696959 |
| [subclasses of antibodies to hepatitis b core antigen in chronic hbv infections: changes during treatment with interferons and predictors of response]. | response to interferon therapy in chronic hepatitis b virus (hbv) carrier is preceded by the appearance of igm class anti-hbc (antibody to hepatitis b core antigen). the temporal relationship and magnitude of the igm anti-hbc response is variable, suggesting that the antibody is not directly involved in hepatocyte lysis, but is merely a marker of a changed state of immunity to the nucleocapsid proteins induced by interferon. igg 1, 2, 3 and 4 did not change during therapy. igg anti-hbc of all su ... | 1990 | 1698593 |
| effects of insertional and point mutations on the functions of the duck hepatitis b virus polymerase. | the polymerase (p) gene of hepadnaviruses encodes a large polypeptide that appears to participate in several steps in the viral life cycle: packaging of viral rna, providing the primer for synthesis of minus-strand dna, synthesizing minus-strand dna from an rna template and plus-strand dna from a dna template, and degrading viral rna in rna-dna hybrids. to assist in the assignment of these functions to domains of the duck hepatitis b virus polymerase protein, we have constructed a series of subs ... | 1990 | 1698997 |
| antigenic mimicry of an immunoglobulin a epitope by a hepatitis b virus cell attachment site. | the pres(21-47) sequence of the hepatitis b virus (hbv) envelope protein is involved in binding of the virus to cell receptors. a protein similarity search revealed a partial homology between this sequence and a segment of the human immunoglobulin a (iga) heavy chain constant region, suggesting that the cell attachment site for hbv might be located on secretory component representing a receptor for polymeric iga. data presented herein do not support this hypothesis but provide evidence for immun ... | 1990 | 1699350 |
| immunological studies before and during interferon therapy in chronic hbv infection: identification of factors predicting response. | lymphoblastoid interferon is effective therapy in some but not all patients with chronic hepatitis b virus infection. to assess whether immunological parameters were predictive of response to interferon therapy, we determined the human leukocyte antigen type, cd4/cd8 ratio, natural killer cell activity, igm anti-hbc antibody levels and concanavalin a-induced lymphocyte proliferative response in 30 patients before treatment. in addition, to investigate the mechanisms of action of interferon in pr ... | 1990 | 1699861 |
| virological examinations of patients with aids-related complex/walter-reed 5 enrolled in a double-blind placebo-controlled study with intravenous gammaglobulin administration. prognostic value of anti-p24 determination. the arc-ivig study group. | thirty patients with aids-related complex/walter-reed 5 enrolled in a placebo-controlled double-blind study with high-dose intravenous gammaglobulin administration were tested by quantitating hiv western blot and other serological tests for viral antibodies. furthermore, conventional virus isolation attempts were performed. absence or loss of p24 antibodies during the study period was associated with progression to aids (p = 0.01) and thereby was an earlier prognostic parameter of a poor prognos ... | 1990 | 1700551 |
| non-a, non-b hepatitis specific antibodies directed at host-derived epitope: implication for an autoimmune process. | a cdna clone (gor47-1) bearing an epitope with an aminoacid sequence grrgqkaksnpnrpl (gor epitope) was isolated from the plasma of a laboratory chimpanzee infected with human non-a, non-b hepatitis (nanbh) agent. the epitope was not encoded by reported sequences of hepatitis c virus (hcv) but instead was coded for by a host cellular sequence. an enzyme-linked immunosorbent assay (elisa) was developed for antibodies to the gor epitope (anti-gor). a patient with acute nanbh produced both igm and i ... | 1990 | 1701012 |
| integration of hepatitis b virus dna into cells of six established human hepatocellular carcinoma cell lines. | the authors successfully established 5 hepatocellular carcinoma cell lines, jhh-1, 2, 4, 5 and 6, derived from hepatitis b surface antigen seronegative patients and one line. jhh-7, from a patient considered to be a hepatitis b virus carrier. in the culture media of any of the jhh cell lines, including jhh-7, hepatitis b surface antigen was not detected by radioimmunoassay. however, in jhh-7, integration of hepatitis b virus dna was confirmed at two sites on the chromosomes of this line by south ... | 1990 | 1701409 |
| hepg2 cell binding activities of different hepatitis b virus isolates: inhibitory effect of anti-hbs and anti-pres1(21-47). | the antigenic relationships among different hepatitis b virus (hbv) isolates were investigated by using monoclonal antibodies (mabs) specific for hbs, pres2 (phsa binding site), and pres1 (hepatocyte receptor-binding site) epitopes in a double immunoradiometric assay. in order to define possible functional differences resulting from structural and antigenic differences in the hbv env protein, the hbv isolates were compared in an in vitro cell-binding assay based on the attachment of 125i-labeled ... | 1991 | 1703368 |
| specific uptake of asialofetuin-tacked liposomes encapsulating interferon-gamma by human hepatoma cells and its inhibitory effect on hepatitis b virus replication. | asialofetuin-tacked liposomes (af-liposomes) encapsulating interferon (ifn)-gamma were bound and internalized into a human hepatoma cell line, hepg2 cells, selectively through asialoglycoprotein receptor, but not non-tacked liposomes (n-liposomes). af-liposomal ifn-gamma was more effective for inhibition of viral dna replication in hepatitis b virus (hbv)-producing clone from hepg2 cells transfected with hbv-dna than n-liposomal ifn-gamma. af-liposomes may increase the therapeutic potential of i ... | 1991 | 1704230 |
| characterization and genetic analysis of alternatively spliced transcripts of hepatitis b virus in infected human liver tissues and transfected hepg2 cells. | the transcriptional map of hepatitis b virus (hbv) has been expanded recently by the discovery of a singly spliced transcript in hepatoma cell lines transfected with cloned viral dna and a doubly spliced one in naturally infected human liver tissues. by the use of reverse transcription and a subsequent polymerase chain reaction, the two spliced hbv rnas were shown to be present in both types of cells. as further evidence, an hbv mutant was constructed and found to exclusively express the singly ... | 1991 | 1705988 |
| [exposition of epitopes of transmembrane protein gp41 of the human immunodeficiency virus on surface capsids of the hepatitis b virus core antigen]. | | 1990 | 1706924 |
| immune response of peripheral blood mononuclear cells to hbx-antigen of hepatitis b virus. | the hepatitis b virus genome encodes a transcriptional transactivator protein designated hbxag. we have investigated whether this antigen is a target structure for human t-lymphocytes. using recombinant hbxag protein, we found hbxag-specific stimulation of peripheral blood mononuclear cells in patients with acute hepatitis b virus infection (6 of 6) and chronic hepatitis b virus infection (6 of 17) but not in healthy individuals. with hbxag-specific synthetic polypeptides, several t-cell epitope ... | 1991 | 1707027 |
| expression of insulin-like growth factor ii, alpha-fetoprotein and hepatitis b virus transcripts in human primary liver cancer. | insulin-like growth factor ii is a fetal growth factor structurally and functionally related to insulin and insulin-like growth factor i. its mrna expression is developmentally regulated in human liver, the reexpression of insulin-like growth factor ii fetal transcripts being often observed in primary liver cancer. insulin-like growth factor ii and alpha-fetoprotein mrnas were studied in 16 human primary liver cancers, most of which were highly differentiated. hepatitis b virus transcripts were ... | 1991 | 1707028 |
| expression of the terminal protein region of hepatitis b virus inhibits cellular responses to interferons alpha and gamma and double-stranded rna. | constructs expressing the core, surface, x, or polymerase proteins of hepatitis b virus were transfected into human cells. in transient assays, only the polymerase inhibited the responses to interferons alpha and gamma (ifn-alpha and -gamma). stable expression of the polymerase was achieved in the cell line 2ftgh, which carries an ifn-inducible marker gene, by growth under conditions that select for inhibition of the response to ifn-alpha, but the clones grew poorly. when expressed alone, the te ... | 1991 | 1707174 |
| [establishment and characterization of a human hepatocellular carcinoma cell line jhh-7 producing alpha -fetoprotein and carcinoembryonic antigen--changes in secretion of afp and cea from jhh-7 cells after heat treatment]. | a human hepatocellular carcinoma cell line, jhh-7, was established from resected liver tumor of a 53 year old male with hepatitis b virus infection. jhh-7 was composed of polygonal epithelial cells and functionally synthesized and secreted human albumin, afp, cea and ferritin. no hbsag was detected in the culture supernatant of jhh-7 cells. changes of secretion of afp and cea from jhh-7 cells after heat treatment was studied using a temperature gradient incubator. secretion of afp decreased alon ... | 1990 | 1707654 |
| hepatitis c virus seroprevalence in italian haemophiliacs injected with virus-inactivated concentrates: five year follow-up and correlation with antibodies to other viruses. | the overall prevalence of anti-hcv antibody in a group of 125 haemophiliacs was 62%. four patients who had never received replacement therapy were anti-hcv negative. of the 121 patients injected regularly with commercial concentrates, 76 were already anti-hcv seropositive in 1985 and remained so throughout the follow-up. two patients seroconverted in 1987 without obvious signs or symptoms of hepatitis. our patients were treated with dry heat-treated concentrates since 1985 and with wet heat- or ... | 1991 | 1707952 |
| differentiating effect of sodium butyrate on human hepatoma cell lines plc/prf/5, hcc-m and hcc-t. | the in vitro effect of sodium butyrate (sb) on human hepatoma cell lines plc/prf/5, hcc-m and hcc-t was investigated. sb was added at the non-toxic but cytostatic concentration of 1 mm. in all these cell lines, sb reduced cell proliferation and changed the morphology of the cells into a fibroblast-like shape. in plc/prf/5, alpha-fetoprotein production and c-myc expression were inhibited. in contrast, gene expression of albumin, one of the normal liver-cell products, and that of integrated hepati ... | 1991 | 1708367 |
| detection of polyadenylated rna in hepatitis b virus-infected peripheral blood mononuclear cells by polymerase chain reaction. | polymerase chain reaction (pcr) with a reverse transcriptase step characterized a specific transcription activity in hepatitis b virus (hbv)-infected peripheral blood mononuclear cells (pbmc) in two patients (1 and 2) with chronic hepatitis positive for antibody to hepatitis b core antigen (hbc). patient 1 was also coinfected with human hepatitis delta virus. a patient who cleared hbv replication after antiviral treatment with vidarabine served as negative control. hbv-specific rna poly a sequen ... | 1991 | 1708401 |
| direct evidence for cytotoxicity associated with expression of hepatitis delta virus antigen. | it has been postulated that hepatocyte injury resulting from infection with hepatitis d virus may be caused by a direct virus cytotoxicity in contrast to immune-mediated injury associated with hepatitis b virus. we have transfected hela and hepg2 continuous cell lines with a recombinant plasmid containing the hepatitis d antigen gene under the inducible control of the human metallothionein promoter. the addition of zinc to the cell culture medium then led to the expression of hepatitis d antigen ... | 1991 | 1709411 |
| pregenomic rna encapsidation analysis of eleven missense and nonsense polymerase mutants of human hepatitis b virus. | we characterized 11 dna polymerase mutants of human hepatitis b virus (hbv) which contain single missense or nonsense mutations in the various domains within this gene. except for mutant 738, a tight association between dna replication and rna packaging of these missense pol mutants was observed. further analysis of hbv core particle-associated rna indicated that only the 3.5-kb core-specific rna, but not the precore-specific rna, is selectively packaged in this tissue culture system. previously ... | 1991 | 1710285 |
| cellular immune responses to hepatitis b virus antigens in man. | | 1991 | 1710754 |
| hepatitis c virus antibodies among different groups at risk and patients with suspected non-a, non-b hepatitis. | 4000 sera were tested for antibodies against hepatitis c virus (hcv) by means of an elisa using the c100-3 antigen. 38.9% of patients with non-a, non-b hepatitis following blood transfusion (n = 108) had hcv antibodies. among patients with chronic liver damage of unknown origin (n = 316) 30.4% were anti-hcv positive, and in 2,506 patients with transitional or chronic elevation of transaminases 14.8% showed hcv antibodies. haemophiliacs (n = 26) with 65.4% anti-hcv positives and drug addicts (n = ... | 1991 | 1711018 |
| inhibitory activity of monoclonal antibody f35.25 on the interaction between hepatocytes (hepg2 cells) and pres1-specific ligands. | the capacity of a pres1-specific monoclonal antibody (mcab) f35.25 to block the attachment of pres1-specific ligands to human hepatoma hepg2 cells was studied. in order to define more precisely the fine epitope specificity of mcab f35.25, its reaction with synthetic peptides derived from the pres1 sequence (12-53) was investigated. mcab f35.25 was found to recognize better synthetic peptide pres(21-47) from the adw 2 and ayw sequences than the synthetic peptide pres(32-53) adw 2. the shortest se ... | 1991 | 1712075 |
| physicochemical and immunological properties of the hepatitis b surface antigen containing the pres2 9 amino acid sequence produced by a recombinant yeast. | the hepatitis b virus surface antigen containing the pres2 nine amino acid sequence produced by a recombinant saccharomyces cerevisiae (yhbsag) was purified and its physicochemical properties were determined. ultrastructurally, the yhbsag was found to be a homogeneous spherical particle with a diameter of 24 +/- 4 nm. the homogeneity of the yhbsag particles was also demonstrated by analyses of their buoyant density and isoelectric point. they consisted of protein (53%), lipid (36%) and carbohydr ... | 1991 | 1712147 |
| characterisation of a linear binding site for a monoclonal antibody to hepatitis b core antigen. | the complete amino acid (aa) sequence of the hepatitis b virus (hbv) core protein (hbcag), ayw subtype, was synthesized as decapeptides with five overlapping aas. the peptides were tested for reactivity with monoclonal antibodies (mabs) to hbcag (35/312, 37/275, and 7/275). all the mabs specifically inhibited human anti-hbc by cross competition in assays for anti-hbc and anti-hbe. the mab 35/312 recognised a peptide covering residues 76-85 of the hbcag sequence. the other two mabs did not react ... | 1991 | 1713264 |
| human and murine b-cells recognize the hbeag/beta (or hbe2) epitope as a linear determinant. | the complete amino acid (aa) sequence of the hepatitis b virus (hbv) core protein (hbcag), deduced from the genome of the hbv ayw subtype, was synthesized as decapeptides with five overlapping aas. the peptides were tested for reactivity with monoclonal antibodies (mabs) to the beta (or hbe2) epitope of hepatitis b e antigen (hbe/b mabs; 57/8, 78/3, 141/158 and 141/207). cross-competition between the mabs with a mab to the hbe/alpha epitope (or hbe1) and an anti-hbc mab showed that all the hbe/b ... | 1991 | 1713295 |
| inhibition of human hepatocellular carcinoma and hepatoblastoma cell lines by deferoxamine. | inhibition of human hepatocellular carcinoma (plc/prf/5 and hep3b) or hepatoblastoma (hep g2) cell lines by inclusion of deferoxamine mesylate (desferrioxamine) (dfx) in the culture medium was evaluated. when plc/prf/5 cells were maintained for 7 days in 30 or 60 microm dfx, the cell number was decreased by 30-60%, little or no alpha-fetoprotein (afp) was produced, and supernatant endpoint dilution titers of hepatitis b surface antigen (hbsag) were reduced 1-2 logs. plc/prf/5 cells maintained fo ... | 1991 | 1715897 |
| phosphorylation in the carboxyl-terminal domain of the capsid protein of hepatitis b virus: evaluation with a monoclonal antibody. | the capsid protein of hepatitis b virus (p21c) is made of 183 amino acids coded for by the c gene. by using p21c isolated from dane particles (hepatitis b virus) as an immunogen, a monoclonal antibody (no. 2212) which recognized an epitope dependent on the phosphorylation of p21c was raised. the binding of no. 2212 antibody to authentic p21c was completely inhibited by a synthetic undecapeptide with a sequence of rrrsqsprrrr, representing amino acids 165 to 175 of p21c, only when the peptide was ... | 1991 | 1717713 |
| identification of t cell epitopes on hepatitis b surface antigen. | the antigenic sites for human t lymphocytes on hepatitis b surface antigen (hbsag) have been studied using synthetic peptides. the results indicate that aminoacid residues 24-28 of hbsag (located near the amino terminus of the hbsag molecule) constitute an immunodominant "helper" determinant, whereas residues 17-18 and/or 34-36 represent a major "suppressor" epitope. however, non responsiveness to currently used hepatitis b virus (hbv) vaccines (employing the whole hbsag molecule) does not depen ... | 1991 | 1720295 |
| cytotoxic t lymphocytes recognize an hla-a2-restricted epitope within the hepatitis b virus nucleocapsid antigen. | the absence of readily manipulable experimental systems to study the cytotoxic t lymphocyte (ctl) response against hepatitis b virus (hbv) antigens has thus far precluded a definitive demonstration of the role played by this response in the pathogenesis of liver cell injury and viral clearance during hbv infection. to circumvent the problem that hbv infection of human cells in vitro for production of stimulator/target systems for ctl analysis is not feasible, a panel of 22 overlapping synthetic ... | 1991 | 1720813 |
| hcv infection, hepatic hla display and composition of the mononuclear cell inflammatory infiltrate in chronic alcoholic liver disease. | viral infection may play a role in alcoholic liver disease with histological features of chronic active hepatitis (cah). human leucocyte antigen (hla) hepatocellular display is supposed to allow hla-restricted t-lymphocyte cytotoxicity in chronic viral hepatitis. we studied the presence of serum anti-hepatitis c virus (hcv) antibodies, the hepatic hla display and the composition of the mononuclear cell infiltrate in 16 patients with alcoholic liver disease and histological features of cah and in ... | 1991 | 1723384 |
| a preliminary report on the intervention trials of primary liver cancer in high-risk populations with nutritional supplementation of selenium in china. | the purpose of this study was to evaluate the effect of selenium (se) in the prevention of human primary liver cancer. three intervention trials were conducted among the residents at high risk to primary liver cancer (plc) in qidong county, jiang-su province, the people's republic of china. this area has the second highest rate of plc in china. one trial was undertaken among the general population in a township with supplement of table salt fortified with 15 ppm anhydrous sodium selenite (se-sal ... | 1991 | 1726411 |
| two vaccinia virus recombinants expressing hbsag with different concentration of a- and pre-s2 antigenic determinants. | comparative studies of two vaccinia virus (vv) recombinants expressing the hepatitis b virus (hbv) surface antigen (hbsag) including the pre-s2 region (m-protein) showed that the l-pre-s2/15 recombinant expressed 5-fold more hbsag as determined by the content of a-determinant than the recombinant v137. however, both recombinants expressed comparable amounts of the pre-s2 antigenic determinant as assessed by enzyme immunoassay with monoclonal antibodies. according to our calculations, one hbsag u ... | 1991 | 1726675 |