Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| molecular aspects of persistent woodchuck hepatitis virus and hepatitis b virus infection and hepatocellular carcinoma. | it seems evident that the development of fully malignant hcc is a multistage process with many variables. one possible mechanism by which many of these variables may interact is as follows. during chronic active hepatitis, viral dna integration occurs randomly and at a low frequency in hepatocytes. integration may be stimulated by the increased rate of hepatocyte cell division resulting from liver necrosis and regeneration during chronic disease. the presence of viral integrations in the cellula ... | 1987 | 3804217 |
| regulation of secretion of the hepatitis b virus major surface antigen by the pres-1 protein. | p24, p30, and p39, the three major surface antigens of the envelope of hepatitis b virus, are co-carboxy-terminal proteins with different amino-terminal extensions. we prompted expression of these proteins in chinese hamster ovary (cho) cells by placing the appropriate coding sequence(s) under the control of the simian virus 40 early promoter. p24 and p30 formed 22-nm particles which were efficiently secreted. in contrast, p39 accumulated in a perinuclear structure, presumably the golgi complex, ... | 1987 | 3806798 |
| infectious influenza a and b virus variants with long carboxyl terminal deletions in the ns1 polypeptides. | an influenza a virus, a/turkey/oregon/71, was shown by protein gel analysis to code for an ns1 protein approximately half the size of those of other influenza a viruses. sequence analysis of the ns gene of this virus revealed a 10 nucleotide deletion resulting in an ns1 protein of only 124 amino acids. this truncated ns1 polypeptide retained its karyophilic pattern as detected by indirect immunofluorescence analysis of virus infected cells. also, a/turkey/oregon/71 virus grew to high titer in em ... | 1987 | 3811235 |
| main properties of duck hepatitis b virus dna polymerase: comparison with the human and woodchuck hepatitis b virus dna polymerases. | the main properties of the duck hepatitis b virus (dhbv) dna polymerase have been studied and compared with those of the human hepatitis b virus (hbv) and of the woodchuck hepatitis virus (whv) dna polymerases. all 3 enzymes are active under high salt conditions in the presence of high magnesium concentration. dhbv dna polymerase was found less sensitive to ethanol and to operate at higher optimal ph than the hbv and whv dna polymerases. like the other two viral endogenous dna polymerases, the d ... | 1987 | 3446017 |
| effects of an extract from phyllanthus niruri on hepatitis b and woodchuck hepatitis viruses: in vitro and in vivo studies. | an aqueous extract of the plant phyllanthus niruri inhibits endogenous dna polymerase of hepatitis b virus and binds to the surface antigen of hepatitis b virus in vitro. the extract also inhibits woodchuck hepatitis virus (whv) dna polymerase and binds to the surface antigen of whv in vitro. the extract, nontoxic to mice, was tested for antiviral activity in woodchucks (marmota monax). in a trial using six long-term whv-carrier woodchucks, five treated animals showed a faster decrease in woodch ... | 1987 | 3467354 |
| hepatocarcinogenicity of the woodchuck hepatitis virus. | during investigations of the evolution of experimental laboratory infections of woodchucks (marmota monax) with the woodchuck hepatitis virus (whv), eight hepatocellular carcinomas (hcc) were observed, six in newborns and two in young adult animals, all within 17-36 months after infection. the absence of an external cocarcinogenic effect in the well-monitored woodchucks indicates the carcinogenicity of whv and suggests the same for the genetically and biologically similar human hepatitis b virus ... | 1987 | 3468514 |
| microbial oncogenesis. | for more than a century, medical investigators have sought to incriminate microorganisms in the cause of cancer. the first scientific evidence of such a relationship came in 1911, with the first successful induction of a tumor using a cell-free extract. since that time, considerable data have accrued linking retroviruses, herpes viruses, the hepatitis b virus, papovaviruses, and adenoviruses to various malignant neoplasms. there is also increasing evidence that certain bacteria and parasites par ... | 1987 | 3541601 |
| maintenance of woodchuck hepatitis virus activity in woodchuck hepatocyte primary culture. | primary cultures of non-proliferating hepatocytes isolated by the two-step collagenase perfusion method from woodchuck naturally infected with hepatitis virus (whv) were used to study whv propagation in vitro. hepatocytes carrying whv dna exhibited a very high level of survival and retained their morphological characteristics for 2 to 3 months. over this time, they were found to produce virus-specific proteins and release viral particles with dna polymerase activity into the medium. using southe ... | 1987 | 3572356 |
| inactivation of influenza b virus by normal guinea-pig serum. | normal guinea-pig serum (gps) lacking detectable antiviral antibody efficiently neutralized the infectivity of influenza b virus grown in chick embryos or mdck cells. the inhibitor was heat-labile and sensitive to trypsin digestion. this beta-like inhibitor required ca2+ and the complement components c1 and c4 for its activity. in contrast, gps did not inactivate influenza a virus. influenza b virus from which the neuraminidase activity of the spikes on the viral envelope had been eliminated by ... | 1987 | 3572357 |
| emerging models in the u.s.a.: swine, woodchucks, and the hairless guinea pig. | swine have been used in biomedical research for many years, but have generally been limited to those locations with personnel familiar with this species and with specially designed facilities and equipment. there is currently a growing trend in the united states for more swine, both miniature and domestic to be used as research models. commercial availability, education through workshops and symposia, and specific research applicability in the areas such as: organ transplantation, cardiovascular ... | 1987 | 3601991 |
| expression of the hepatitis b virus core gene in vitro and in vivo. | the core gene of hepatitis b virus contains two in-phase aug codons which may both be used in the viral life cycle. by in vitro translation of transcripts produced in vitro, we investigated the corresponding core gene products and their counterparts in vivo. depending on the location of the 5' end of the transcripts, two major core gene-derived proteins were obtained. in transcripts with both in-phase augs, only the first one was efficiently used and resulted in synthesis of a 25-kilodalton prot ... | 1987 | 3625840 |
| a cultured cell receptor for the small s protein of hepatitis b virus. | human hepatitis b virus (hbv) has not been passaged in established cell culture systems. to determine whether this inability results from the lack of a receptor, 30 cell lines were examined for their abilities to bind 125i-labeled recombinant hepatitis b virus surface antigen (rhbsag) particles. these particles contained only the small surface (s) protein, which is also found in the envelope of infectious hbv particles. only two cells lines, both derived from african green monkey kidney, were ab ... | 1987 | 3629972 |
| [detection and identification of host cell antigens in the composition of influenza b virus]. | two heterogeneous antigens, forssman antigen and an antigen similar to human group a antigen, were detected by enzyme-immunoassay in cells of normal chick embryo camn and mdck culture (dog kidney). both these antigens were associated with purified influenza b virus preparations reproduced in these cultures since the variants under study actively reacted with antibodies both to forssman antigen and to human a antigen. serological differences between the variants grown in different cell systems we ... | 1987 | 3300030 |
| liver tumors in rodents: extrapolation to man. | man is a poor model for the prediction of agents that are hepatocarcinogenic for laboratory rodents. relatively few agents are known to cause any form of primary liver cancer in man. the most important is hepatitis b virus, for which there is possibly a model in the woodchuck but not one in rats or mice. the only other agents known to cause primary liver cancer in man are certain steroid hormones, vinyl chloride, and thorium dioxide. there are animal models for the first two of these and a reaso ... | 1987 | 3300204 |
| integration of hepatitis b virus: analysis of unoccupied sites. | hepatitis b virus (hbv) sequences integrated in the plc/prf/5 cell line (alexander cells), which was derived from a human primary liver carcinoma, were previously extensively studied. here we describe the analysis of the unoccupied sites of two linearly integrated forms of hbv dna, al-14 and al-26, that were characterized previously. no major cellular dna rearrangements were seen at the integration sites except for small deletions of host sequences: 2 kilobases of dna in al-14 and 17 base pairs ... | 1987 | 3029413 |
| [hbv and hepatocellular carcinoma]. | significant research evidence has demonstrated an association between persistent infection with hepatitis b virus (hbv) and the generation of hepatocellular carcinoma (hcc). these findings are based on epidemiologic studies, molecular studies and studies of hbv like viruses. epidemiologically, the geographic correlation between hbv infection and hcc, serum hbsag in patients with hcc, familial clustering of hcc, prospective studies, and pathological studies are discussed. molecular studies of hbv ... | 1987 | 3030195 |
| in vitro recombinants of ground squirrel and woodchuck hepatitis viral dnas produce infectious virus in squirrels. | hepatitis b viruses of humans, woodchucks, ground squirrels, and ducks are similar biochemically but differ with respect to host range and pathogenicity. to pursue the genetic basis of these properties in the absence of a cell culture system for virus growth, we exploited the demonstrated infectivity of cloned hepatitis b virus dna in whole animals. we constructed several recombinant molecules in vitro between cloned infectious genomes of woodchuck hepatitis virus (whv) and ground squirrel hepat ... | 1987 | 3041044 |
| the florey lecture, 1986. vaccine prevention of virus-induced human cancers. | carcinogenic viruses have been discovered in numerous animal species over the last 80 years but their role in human cancer has only recently become an important issue. with eb virus involved with endemic burkitt's lymphoma and undifferentiated nasopharyngeal carcinoma, hepatitis b virus with primary liver cancer, papilloma viruses with carcinoma of the cervix, and t-cell leukaemia virus with adult t leukaemia, 20-25% of all human cancer appears to have a virus component in its causation. by anal ... | 1987 | 2884667 |
| [experimental infection of human hepatitis b virus (hbv) in adult tree shrews]. | 1987 | 2962750 | |
| production of hepatitis b virus surface antigen particles by the human hepatoma cell line hugk-14 in a serum-free medium. | the human hepatoma cell line, hugk-14, containing integrated hepatitis b virus (hbv) dnas, produced a large number of 23 nm spherical particles of hbv surface antigen (hbsag) in a serum-free medium. these particles closely resembled the hbsag particles found in the sera of hbv carriers and elicited a high antibody response in guinea pigs. the hugk-14 cells in a serum-free medium would provide a new, economic source of hbv vaccine. | 1987 | 2828295 |
| products of the "x" gene in hepatitis b and related viruses. | the x region in hepatitis b virus dna potentially encodes a polypeptide 154 amino acids in length. two synthetic peptides spanning residues 100 to 115 (peptide 99) and 115 to 131 (peptide 100) in a hydrophilic domain within the carboxy terminal third of the proposed gene product were made and used to raise peptide antisera in rabbits. such antisera specifically bound to x reactive determinants in liver-derived core antigen particles from humans (hbcag), ducks (dhbcag), ground squirrels (gshcag) ... | 1986 | 2420692 |
| structure and replication of the genome of the hepatitis delta virus. | the hepatitis delta virus can be found in the serum and liver of some hepatitis b virus patients. we now report that the rna genome of serum-derived delta virus is single-stranded and circular. livers of infected chimpanzees or woodchucks contained as many as 300,000 copies of genomic strand rna per average cell, and at least some of this rna had a circular conformation. also present in the livers were rna species complementary to the virion rna. the genomic rna was 5-22 times more abundant than ... | 1986 | 2430299 |
| evidence for the presence of duck hepatitis b virus in wild migrating ducks. | a virus closely related to duck hepatitis b virus (dhbv) was isolated from serum and liver samples of wild migratory ducks (mallards) caught in two separate wildlife reserve parks in france. in the first one (dombes region) 12% of wild mallards were positive for dhbv, and in the second (river somme) 3% of mallards were found positive. the dhbv isolated from the serum of wild mallards was also associated with an endogenous dna polymerase activity capable in vitro of completing a partially double- ... | 1986 | 3005480 |
| herpes simplex virus complement fixing antibody and herpes b virus serum neutralizing antibody in sera of wild and laboratory-bred cynomolgus monkeys. | the result of the complement fixation (cf) test for the antibody to herpes simplex virus (hsv) in sera of the cynomolgus monkeys was compared with that of the neutralization test (ns) for the antibody to herpes b virus (hbv) in the same sera. fifty-seven (74%) of 77 wild-originated monkeys were positive for hsv-cf, while 65 (84%) of the 77 animals were positive for hbv-sn. all of the 57 cf positive cases were also positive for hbv-sn. on the other hand, 30 (75%) of 40 laboratory-bred monkeys had ... | 1986 | 3011466 |
| hepatocellular carcinoma in ground squirrels persistently infected with ground squirrel hepatitis virus. | although persistent infection with hepatitis b virus and woodchuck hepatitis virus has been associated with development of hepatocellular carcinoma in the host, little has been known of such an association with ground squirrel hepatitis virus (gshv), which is closely related to the woodchuck virus. colonies of gshv-infected and -uninfected beechey ground squirrels were observed for tumors for a period of 5 years. tumors developed in seven squirrels after a minimum of 2.4 years of observation per ... | 1986 | 3012572 |
| a recombinant chinese hamster ovary cell line containing a 300-fold amplified tetramer of the hepatitis b genome together with a double selection marker expresses high levels of viral protein. | a new series of double-selection plasmids containing recombinant genes expressing the neomycin phosphotransferase (neo) of transposon tn5 and mouse dihydrofolate reductase (dhfr) in mammalian cells is described. activity of the recombinant dhfr gene varied more than 50-fold, depending on the location of the simian virus 40 72 base-pair repeat or enhancer, which is part of the promoter of the neo unit. a neo-dhfr module with the enhancer located at the 3' end of the dhfr gene was inserted into a ... | 1986 | 3023626 |
| protection of chimpanzees from type b hepatitis by immunization with woodchuck hepatitis virus surface antigen. | two chimpanzees immunized with woodchuck hepatitis virus (whv) surface antigen (whsag) developed antibodies cross-reactive with hepatitis b virus (hbv) surface antigen (hbsag). after challenge with hbv, one animal was completely protected and the other experienced a subclinical infection, without evidence of liver disease. three woodchucks immunized with hbsag developed antibodies to hbsag which did not cross-react with whsag. after challenge with whv, all three woodchucks developed typical acut ... | 1986 | 3783820 |
| failure to detect polyalbumin-binding sites on the woodchuck hepatitis virus surface antigen: implications for the pathogenesis of hepatitis b virus in humans. | binding sites for polymerized albumin on hepatitis b virus components were reported in human hepatitis b virus chronic carriers predominantly with active viral replication (hb e antigen positive). the presence of comparable albumin-binding sites in the woodchuck hepatitis virus (whv) model was examined on whv components obtained from woodchucks with active viral replication (dna polymerase positive). binding sites for polymerized woodchuck serum albumin were not detected on the intact whv virion ... | 1986 | 3783821 |
| hepadnavirus infection of peripheral blood lymphocytes in vivo: woodchuck and chimpanzee models of viral hepatitis. | the peripheral blood lymphocytes (pbl) of five hepatitis b virus (hbv)-infected chimpanzees and 17 woodchuck hepatitis virus (whv)-infected woodchucks were examined for the presence of viral dna and rna. hbv dna was detected in the pbl of three of three chronically infected chimpanzees but in neither of two animals with acute hbv infection. whv dna was found in the pbl of 11 of 13 chronically infected woodchucks and in the pbl and bone marrow of 1 of 4 woodchucks with antibody to whv surface ant ... | 1986 | 3485201 |
| intracellular assembly and packaging of hepatitis b surface antigen particles occur in the endoplasmic reticulum. | hepatitis b surface antigen (hbsag) particles are secreted by chinese hamster ovary cells that are stably transfected with the s gene of hepatitis b virus. the assembly of hbsag into cylindrical and spherical particles occurred intracellularly within the endoplasmic reticulum. hbsag particles accumulated within large dilated areas of the endoplasmic reticulum and remained within these structures for most of the time prior to secretion from the cells. once the particles were formed, the hbsag pol ... | 1986 | 3517385 |
| common evolutionary origin of hepatitis b virus and retroviruses. | hepatitis b virus (hbv), although classified as a double-stranded dna virus, has been shown recently to replicate by reverse transcription of an rna intermediate. also, the putative viral polymerase has been found to share amino acid homology with reverse transcriptase of retroviruses. using computer-assisted dna and protein sequence analyses, we examined the genomes of 13 hepadnavirus isolates (nine human, two duck, one woodchuck, and one ground squirrel) and found that other conserved regions ... | 1986 | 3458214 |
| nucleotide sequence of a cloned woodchuck hepatitis virus genome: evolutional relationship between hepadnaviruses. | we have determined the complete nucleotide sequence of a cloned dna of woodchuck hepatitis virus (whv), the most oncogenic virus among hepadnaviruses. the genome, designated whv2, is 3,320 base pairs long and contains four major open reading frames (orfs) coded on the same strand of nucleotide sequence as in the human hepatitis b virus (hbv) genome. comparison of the nucleotide sequence and amino acid sequences deduced from it among the genomes of various hepadnaviruses demonstrates that each pr ... | 1985 | 3855246 |
| duck hepatitis b virus dna in liver and serum of chinese ducks: integration of viral dna in a hepatocellular carcinoma. | the presence of duck hepatitis b virus (dhbv) dna in liver and serum and its state (integrated vs. free) were studied in 23 ducks from chi-tung county in china by spot hybridization and southern blot hybridization, respectively. in 16 of 23 (70%), dhbv dna was detected in serum and/or in liver tissue. these infected ducks showed a variety of pathological changes including advanced chronic disease in the liver. in contrast, none of the virus-negative ducks had advanced hepatic changes. one dhbv d ... | 1985 | 3860852 |
| detection of an igm antiidiotype directed against anti-hbs in hepatitis b patients. | an igm-specific anti-[anti-hbs] antibody was detected by radioimmunoassay using anti-igm-coated beads and 125i-labeled anti-hbs. this antiidiotype was found only in the sera of hepatitis b virus-infected patients, both acute and chronic. however, not all hbsag-positive patients exhibited this reaction, and activity was correlated with the presence of hbeag. approximately 93% of sera that contained antiidiotype activity also contained hbeag. conversely, 70% of the sera positive for hbeag reacted ... | 1985 | 3875543 |
| the hbv hbx gene expressed in e. coli is recognised by sera from hepatitis patients. | we have cloned the x gene (hbx) and the hbc antigen (hbc ag) gene of human hepatitis b virus (hbv) in escherichia coli as fusion products with beta-galactosidase. both hbv genes are expressed in e. coli strain csr 603. expression is detected by u.v. irradiation of the bacteria, metabolic labelling and electrophoresis of the labelled extracts on sds-polyacrylamide gels. the hbc ag protein produced in bacteria can be recognised by anti-hbc sera and peptides derived from the protein are also recogn ... | 1985 | 3891326 |
| establishment of a cell line from a woodchuck hepatocellular carcinoma. | a new cell line derived from a woodchuck hepatocellular carcinoma serially transplanted in athymic nude mice has been established and named wh257ge10. the original tumor in the nude mouse system produces woodchuck hepatitis surface antigen and albumin. in addition, woodchuck hepatitis virus dna is integrated into cellular dna. adaptation of the cells to the in vitro culture condition was completed after 15 months with the doubling time of 40 hr. the morphologic features of the cell by light micr ... | 1985 | 3905560 |
| neuraminic acid is involved in the binding of influenza c virus to erythrocytes. | neuraminidases of both viral and bacterial origin have been reported to be unable to destroy the cellular receptor for influenza c virus on chicken erythrocytes, in contrast to the receptors for influenza a and b virus. however, under appropriate conditions neuraminidases from both vibrio cholerae and clostridium perfringens were able (i) to make chicken red blood cells resistant against agglutination by influenza c virus and (ii) to reduce the hemagglutination-inhibiting activity of rat serum. ... | 1985 | 3976175 |
| radioimmunoassay and characterization of woodchuck hepatitis virus core antigen and antibody. | solid-phase radioimmunoassays for woodchuck hepatitis virus core antigen (whcag) and antibody (anti-whc) were developed. whcag in woodchuck liver homogenates was characterized by ultracentrifugation in cscl gradients; both heavy (1.35 g/cm3) and light (1.31 g/cm3) cores were obtained from the liver of an animal during acute whv infection, which is consistent with observations in hepatitis b virus infection in man. endpoint titers of anti-whc were higher in chronic whv carriers than in animals re ... | 1985 | 4036315 |
| subacute nonsuppurative hepatitis associated with hepatitis b virus infection in two cynomolgus monkeys. | subacute, nonsuppurative hepatitis was diagnosed in a cynomolgus monkey (macaca fascicularis) based on histopathologic examination of a liver biopsy specimen. clinical signs of illness included anorexia, lethargy and hepatomegaly. abnormal laboratory findings included elevations of serum liver enzymes, bilirubin and a monocytosis. circulating antibody (anti-hbs) against hepatitis b surface antigen (hbsag) was present in serum and antigens reactive with anti-hbsag antiserum were found in the live ... | 1985 | 4046551 |
| [circulation of the influenza virus on poultry-raising farms]. | the results of examinations for immunity to influenza in chickens and the personnel handling them at the permanently observed farm are presented. antibodies mainly to the same antigenic variants of human influenza viruses were found in chicken and human blood sera. alongside with antihemagglutinins to influenza a (h3n2) virus strains, chicken in 1983-1984 were found to have antibodies to influenza b virus epidemically important in those years. thus, in poultry farms human influenza viruses are i ... | 1985 | 4049842 |
| alterations in the hemagglutinin associated with adaptation of influenza b virus to growth in eggs. | in 1943 burnet reported on changes in the hemagglutinating properties of human influenza virus which occurred during adaptation of the virus to growth in chicken eggs. only recently has direct evidence been presented that these changes affect the antigenic properties of the virus. schild et al. (g. c. schild, j. s. oxford, j. c. dejong, and r. g. webster (1983), nature (london) 303, 706-709) demonstrated that egg adaptation of influenza b virus selects variants which are antigenically distinct f ... | 1985 | 4060580 |
| nucleotide sequence of an infectious molecularly cloned genome of ground squirrel hepatitis virus. | we have determined the complete nucleotide sequence of an infectious cloned genome of ground squirrel hepatitis virus (gshv), a nonpathogenic member of the hepadnavirus group. the genome is 3,311 base pairs long and contains the major open reading frames described for the related human and woodchuck hepatitis b viruses (hbv and whv, respectively). these reading frames include genes for the major structural proteins (the surface and core antigens), unassigned open reading frames (a and b), the lo ... | 1984 | 6086950 |
| synthesis in animal cells of hepatitis b surface antigen particles carrying a receptor for polymerized human serum albumin. | a recombinant plasmid (psvs dhfr) encoding the pre-s region and the s gene of human hepatitis b virus (hbv) and murine dihydrofolate reductase (dhfr) cdna has been used for the transfection of chinese hamster ovary (cho) dhfr- cells. selection of clones resistant to methotrexate has permitted amplification of hbv sequences and an increase in production of hepatitis b surface antigen (hbsag). hbv-specific transcripts have been characterized. the hbsag 22-nm particles contain a receptor for polyme ... | 1984 | 6096851 |
| a transformed vero cell line stably producing the hepatitis b virus surface antigen. | we have constructed plasmids in which transcription of the surface antigen gene of the human hepatitis b virus (hbsag) is under the control of the sv40 early promoter. these plasmids have been used to analyze the expression of the hbsag gene, both in mouse cells and in african green monkey kidney (vero) cells. we have established a vero cell line continuously expressing hbsag that is indistinguishable from authentic 22 nm hbsag particles. post-transcriptional modification of hbsag mrna also appe ... | 1984 | 6098537 |
| liver carcinogenesis in tropical africa. | the geographical pathology of hepatocellular carcinoma (hcc) was essentially anecdotal until systematic cancer registration was introduced, but it is now clear that sub-saharan africa is a high-incidence area. the disease is multifactorial in etiology, the possible etiological agents including hepatitis b virus and a number of chemical carcinogens, among which the most important appear to be the aflatoxins and n-nitroso compounds. medicinal plants and herbal teas used in the tropics also contain ... | 1984 | 6100283 |
| sarcoma growth in 15i5 x 7(2) chickens infected with avian sarcoma viruses of subgroup b or g. | a comparative study was made of sarcoma growth in 15i5 x 7(2) chickens infected in the wing web at 4 weeks of age with strains of subgroup b or g avian sarcoma viruses. infection with sarcoma viruses of either subgroup b or g resulted in the formation of progressive wing web sarcomas at the site of inoculation. the survival times of the subgroup g virus-infected chickens were generally at least twice as great as the survival times of the subgroup b virus-infected chickens, which averaged 6-9 wee ... | 1984 | 6100579 |
| liver orcein stain and viral dna in duck hepatitis b virus infection in chinese ducks and experimentally infected japanese ducklings. | liver sections were stained with orcein, and duck hepatitis b virus was identified in sera and livers by the hybridization technique in 106 ducks (44 chinese ducks, 15 japanese ducks and 47 japanese ducklings). orcein-positive hepatocytes were found in 18 of 38 (47%) duck hepatitis b virus dna seropositive ducks, and only in 3 of 68 (4%) seronegative ducks. the three ducks were all from a heavily infected flock in southern china. serial analyses of viral dna by southern blot and spot hybridizati ... | 1984 | 6209199 |
| comparison of properties of woodchuck hepatitis virus and human hepatitis b virus endogenous dna polymerases. | the principal properties of the dna polymerases of woodchuck hepatitis virus and human hepatitis b virus were compared. the enzymes of both viruses exhibited optimal activities in the same range of ph, ionic strength, and mgcl2 concentration. like human hepatitis b virus dna polymerase, the woodchuck hepatitis virus dna polymerase was strongly inhibited by phosphonoformic acid but not by phosphonoacetic acid and aphidicolin. similar inhibition patterns for both enzymes were observed with arabino ... | 1984 | 6231885 |
| human hepatitis b vaccine from recombinant yeast. | the worldwide importance of human hepatitis b virus infection and the toll it takes in chronic liver disease, cirrhosis and hepatocarcinoma, make it imperative that a vaccine be developed for worldwide application. human hepatitis b vaccines are presently prepared using hepatitis b surface antigen (hbsag) that is purified from the plasma of human carriers of hepatitis b virus infection. the preparation of hepatitis b vaccine from a human source is restricted by the available supply of infected h ... | 1984 | 6318124 |
| woodchuck hepatitis virus: experimental infection and natural occurrence. | sera from 588 woodchucks were assayed for woodchuck hepatitis virus (whv) markers using hepatitis b virus (hbv) reagents which have cross-reactivity with whv markers. twenty per cent of these woodchucks, trapped in delaware, maryland and pennsylvania, had whsag; 50% of these had dna polymerase. there are areas of high and low endemicity within these states. female woodchucks may have a higher incidence of whv markers than do males. woodchuck hepatitis surface antigen (whsag) and anti-whc often o ... | 1984 | 6383996 |
| core antigen and antibody in woodchucks after infection with woodchuck hepatitis virus. | the woodchuck hepatitis virus is a naturally occurring hepatitis b-like virus that infects the eastern woodchuck. direct immunofluorescence staining for woodchuck hepatitis virus core antigen in liver biopsies demonstrated the presence of this antigen in 14 of 17 chronically infected woodchucks, and in 8 of 10 woodchucks undergoing acute infections. fluorescent localization of woodchuck hepatitis virus core antigen was typically cytoplasmic, and this was confirmed further by electron microscopy. ... | 1984 | 6384556 |
| [spontaneous and experimental infection of alpine marmots (marmota marmota) by the north american woodchuck hepatitis virus (marmota monax). initial results]. | summer's discovery in 1978 of a dna virus, very close to human hepatitis b virus in a woodchuck population in the u.s.a. (pennsylvania) was a confirmation of the first description made by snyder at penrose research laboratory (philadelphia). it was the first animal model of human b hepatitis infection. the comparative study of morphological, ecological and ethological characteristics of the marmot (marmota marmota) and the woodchuck (marmota monax) enables an easy distinction between these two s ... | 1984 | 6532649 |
| inhibition of human and woodchuck hepatitis virus dna polymerase by the triphosphates of acyclovir, 1-(2'-deoxy-2'-fluoro-beta-d-arabinofuranosyl)-5-iodocytosine and e-5-(2-bromovinyl)-2'-deoxyuridine. | the triphosphates of acyclovir (acv), 1-(2'-deoxy-2'-fluoro-beta-d-arabinofuranosyl)-5-iodocytosine (fiac) and e-5-(2-bromovinyl)-2'-deoxyuridine (bvdu) have been examined for their inhibitory effects on the endogenous dna polymerase reactions of human hepatitis b virus (hbv) and woodchuck hepatitis virus (whv). all three triphosphates (acvtp, fiactp and bvdutp) inhibited the hbv and whv dna polymerases by competing with the corresponding natural substrates. fiactp was the most potent inhibitor ... | 1984 | 6541455 |
| liver disease associated with duck hepatitis b virus infection of domestic ducks. | the liver disease associated with duck hepatitis b viremia was investigated in naturally infected ducks from chi-tung county in china and in both naturally and experimentally infected ducks from the united states. liver and serum specimens of adult chinese ducks were examined for duck hepatitis b virus (dhbv) dna by dot and gel blot hybridization. dhbv was found in serum and (in episomal form only) in livers of 6 of 11 birds exhibiting various degrees of chronic hepatitis. in 1 bird with hepatoc ... | 1984 | 6583686 |
| transmission of the hepatitis b virus-associated delta agent to the eastern woodchuck. | delta agent of human origin was inoculated into four woodchucks chronically infected with woodchuck hepatitis virus (whv). the animals developed delta infections with serologic patterns similar to those previously observed in human and chimpanzee infections. delta antigen was detected transiently in serum and liver and was followed by seroconversion to anti-delta antibody. analogous to the chimpanzee model of delta infection, serum and hepatocyte markers of whv were suppressed in the woodchuck d ... | 1984 | 6585793 |
| predicted secondary structure similarity in the absence of primary amino acid sequence homology: hepatitis b virus open reading frames. | proteins that are related evolutionarily may have diverged at the level of primary amino acid sequence while maintaining similar secondary structures. computer analysis has been used to compare the open reading frames of the hepatitis b virus to those of the woodchuck hepatitis virus at the level of amino acid sequence, and to predict the relative hydrophilic character and the secondary structure of putative polypeptides. similarity is seen at the levels of relative hydrophilicity and secondary ... | 1984 | 6585835 |
| nucleotide sequence of a cloned duck hepatitis b virus genome: comparison with woodchuck and human hepatitis b virus sequences. | the nucleotide sequence of an ecori duck hepatitis b virus (dhbv) clone was elucidated by using the maxam and gilbert method. this sequence, which is 3,021 nucleotides long, was compared with the two previously analyzed hepatitis b-like viruses (human and woodchuck). from this comparison, it was shown that dhbv is derived from an ancestor common to the two others but has a slightly different genomic organization. there was no intergenic region between genes 5 and 8, which were fused into a singl ... | 1984 | 6699938 |
| combined interferon-alpha 2, rimantadine hydrochloride, and ribavirin inhibition of influenza virus replication in vitro. | recombinant dna-produced human interferon-alpha 2 inhibited the replication of influenza a and b viruses in primary rhesus monkey kidney cells (rmk). human interferon-alpha 2 interacted additively or synergistically with rimantadine hydrochloride or ribavirin in reducing the yield of clinical isolates of either h3n2 or h1n1 subtype influenza a viruses. the combination of human interferon-alpha 2 and ribavirin also inhibited the replication of an influenza b virus to a greater extent than either ... | 1984 | 6703684 |
| transmission of duck hepatitis b virus from chinese carrier ducks to japanese ducklings: a study of viral dna in serum and tissue. | human hepatitis b-like viruses have been found in several animal species, including chinese ducks. sera from chinese carrier ducks which were positive for duck hepatitis b virus (dhbv) were inoculated in 33 japanese one-day-old ducklings. the same sera were inoculated in four 3-week-old ducklings, and three 3-month-old ducks. ten uninoculated ducklings served as controls. hepatitis b e-antigen positive human sera and dna polymerase-positive woodchuck sera were also inoculated into ducklings. dhb ... | 1984 | 6745848 |
| detection of interspecies idiotypic cross-reactions associated with antibodies to hepatitis b surface antigen. | a common idiotype was defined by a rabbit anti-idiotypic antiserum generated against human antibodies to hepatitis b surface antigen (anti-hbs). this idiotype was detected in anti-hbs from eight different individuals who had been previously infected with hepatitis b virus and is referred to as the chbs idiotype. the chbs idiotype was also identified in sera from rabbits, mice, guinea pigs, swine, goats and chimpanzees that had been immunized with hepatitis b surface antigen (hbsag). expression o ... | 1983 | 6832213 |
| antigenic cross-reactions between woodchuck hepatitis virus and human hepatitis b virus shown by immune electron microscopy. | using immune electron microscopy (iem), low-level cross-reactions could be demonstrated between the surface antigens of hepatitis b and woodchuck hepatitis. however, immune complex formation was greatly enhanced by pre-exposure of the antigens to 0.5% deoxycholate. cross-reaction between the core antigens and e antigens of both viruses was also confirmed by iem as well as radioimmunoassay. it appears that the woodchuck sera used in this study may well contain an anti-immunoglobulin akin to rheum ... | 1983 | 6834011 |
| antibody to hepatitis b surface antigen in nonprimate animal species. | the hepatitis b virus infects only humans and higher apes. viruses similar to the human hepatitis b virus (hepadna viruses) have been discovered in several nonprimate species including woodchucks, ground squirrels, and domesticated ducks. to search for other models of hepatitis b virus infection, we screened serum specimens from 64 exotic animals (24 species), 56 domesticated animals (6 species), and 52 laboratory animals (3 species). samples were tested for deoxyribonucleic acid polymerase by e ... | 1983 | 6840476 |
| nonoverlapping antigenic sites of woodchuck hepatitis virus surface antigen and their cross-reactivity with ground squirrel hepatitis virus and hepatitis b virus surface antigens. | five nonoverlapping antigenic sites (sites i through v) of woodchuck hepatitis virus surface antigen were identified with competitive binding assays involving monoclonal antibodies. site i contributed to cross-reactions among surface antigens of hepatitis b-like viruses infecting woodchucks, ground squirrels, and humans. at least three distinct sites (sites i, ii, and iii) are responsible for cross-reactions between woodchuck and ground squirrel hepatitis virus surface antigens. sites iv and v o ... | 1983 | 6864882 |
| transplantation of woodchuck hepatocellular carcinoma in nude mice. | woodchuck hepatocellular carcinoma has been successfully transplanted into nude (athymic) mice. the morphology of heterotransplanted tumor is similar to that of naturally occurring hepatocellular carcinoma before transplantation. the growth rate of transplanted tumor was very slow compared with those of other transplanted tumors. during the first month, only two tumors appeared. however, definitive tumor growth was noted in 6 of 20 nude mice about 3 months later. seventeen of 20 nude mice exhibi ... | 1983 | 6618433 |
| use of the cross-reactivity with hepatitis b virus antigens and antibodies for the demonstration of a woodchuck hepatitis virus 'e' antigen-antibody system. | woodchucks hepatitis virus (whv)-associated antigens and antibodies were studied using current sensitive radio- or enzyme immunoassays (ria, eia). a significant cross-reactivity was observed between hepatitis b surface antigen (hbsag) and woodchuck hepatitis surface antigen (whsag) using ria or eia (abbott laboratories, north chicago, ill., u.s.a.) although not with two other commercial eia tested (organon technika, oss, the netherlands; behringwerke ag, marburg, f.r.g.). a weak but significant ... | 1983 | 6619256 |
| the nature of polypeptides larger in size than the major surface antigen components of hepatitis b and like viruses in ground squirrels, woodchucks, and ducks. | the relationships of various polypeptides associated with hepatitis b surface antigen (hbsag), ground squirrel hepatitis surface antigen (gshsag), woodchuck hepatitis surface antigen (whsag), and duck hepatitis b surface antigen (dhbsag) were studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and tryptic peptide mapping. analysis of independent antigen isolates by sds-page resulted in bands consistently observed at 24,000, 28,000, 32,000, 43,000, and 50,000 da with h ... | 1983 | 6636542 |
| hepatitis b virus encodes an rna polymerase iii transcript. | we demonstrated that cloned hepatitis b virus (hbv) dna directs the synthesis of a 700-base rna (hbv 700) by rna polymerase iii in a cell-free transcription system. hbv 700 is the only transcript known to originate from the viral short strand and has been mapped to the region between roughly 1,635 and 954 base pairs on the viral map, between the surface and core antigen coding sequences but overlapping and opposing the putative dna polymerase and b protein genes. the in vitro initiation sites fo ... | 1983 | 6646123 |
| transforming capacities of avian erythroblastosis virus mutants deleted in the erba or erbb oncogenes. | mutants of avian erythroblastosis virus (aev) were constructed by deleting large nucleotide segments in each of the viral oncogenes termed v-erba and v-erbb. mutants in erba (erba -b +) retained the ability to transform fibroblasts in vitro, and these cells exhibited most of the transformation characteristics that typify wild-type aev-transformed fibroblasts. in addition, the mutants induced small erythroid colonies upon infection of bone marrow cells in culture. chickens inoculated with erba -b ... | 1983 | 6297784 |
| rearrangement of the surface antigen gene of hepatitis b virus integrated in the human hepatoma cell lines. | the rearrangement of integrated hbv dna sequences in three different hepatoma cell lines, huh-1, huh-2, kg-55-t from japanese patients, were studied by blot hybridization using whole hbv genome or a hbsag or hbcag dna as a probe. the characteristic existence of multiple integration sites of hbv dna sequences in each hindiii-restricted hepatoma cell dna was revealed by the hbv genome probe. detection of the isolated hbsag gene in the hindiii fragment indicates that the integration of hbv dna was ... | 1983 | 6310497 |
| potency tests for hepatitis b virus vaccines in laboratory animals. | the production of a vaccine for use in humans using the plasma of persistent hepatitis-b virus antigen carriers is a recent development in preventive medicine. this new approach requires strict regulations as to quality control. one of these aspects is the immunogenicity of the vaccine that can be tested in laboratory animals, in which the anti-hbs formation is considered through average titre determinations or through an ed 50 test for seroconversion. both these determinations performed on mice ... | 1983 | 6228477 |
| cloning and structural analysis of integrated woodchuck hepatitis virus sequences from hepatocellular carcinomas of woodchucks. | woodchuck hepatitis virus (whv), like the related hepatitis b virus, induces in its natural host hepatocellular carcinomas that contain integrated viral sequences. as a first step in determining whether and how the integrated sequences contribute to formation of the tumors in which they are found, we have cloned two such integrations of whv and have determined their structure by restriction mapping and heteroduplex electron microscopy. the identity of the cloned sequences was confirmed by compar ... | 1982 | 6288257 |
| novel forms of woodchuck hepatitis virus dna isolated from chronically infected woodchuck liver nuclei. | we cloned several unique forms of woodchuck hepatitis virus, a dna virus closely related to hepatitis b virus, from a chronically infected woodchuck liver. each of the three clones contained more than two genome equivalents of viral sequences with extensive rearrangements and no detectable cellular sequences. from the frequency by which they were isolated from a library of recombinant clones, we estimate that they are present in approximately one copy per cell. of a total of 11 sites at which re ... | 1982 | 6294334 |
| specificity of hepatitis b virus affinity for human hepatic tissue. | using radiolabeled purified hepatitis b surface antigen and human liver slices, the affinity of hepatitis b virus to its host organ was evaluated. saturable adsorption of the 125i-hbs ag complex to liver was demonstrated over both time and complex concentration which could be blocked by excess unlabeled antigen. the specific binding was not found using human pancreas, lung, or kidney tissue. correspondingly, no specific binding could be found for murine liver but it could be demonstrated with wo ... | 1982 | 7069406 |
| nucleotide sequence of a cloned woodchuck hepatitis virus genome: comparison with the hepatitis b virus sequence. | the complete nucleotide sequence of a woodchuck hepatitis virus genome cloned in escherichia coli was determined by the method of maxam and gilbert. this sequence was found to be 3,308 nucleotides long. potential atg initiator triplets and nonsense codons were identified and used to locate regions with a substantial coding capacity. a striking similarity was observed between the organization of human hepatitis b virus and woodchuck hepatitis virus. nucleotide sequences of these open regions in t ... | 1982 | 7086958 |
| presence and state of woodchuck hepatitis virus dna in liver and serum of woodchucks: further analogies with human hepatitis b virus. | 1982 | 7112938 | |
| biological characterization of acute infection with ground squirrel hepatitis virus. | ground squirrel hepatitis virus (gshv) is a small dna virus, structurally and antigenically related to the human hepatitis b virus, which occurs naturally among certain wild populations of ground squirrels (p. l. marion et al., proc. natl. acad. sci. u.s.a. 77:2941-2945, 1980). serum from naturally infected animals was used to transmit gshv in the laboratory by parenteral inoculation of susceptible squirrels. sixty percent of recipient animals developed viral surface antigenemia after a latent p ... | 1982 | 7143570 |
| antibody to hepatitis b virus surface and core antigens in gambia pouched rats (cricetomys gambianus). | sera from 108 cricetomys gambianus (gambia pouched rat) were investigated for hbv and hav serum markers. 42.6% of them evidenced anti-hbs and 12.0% anti-hbc. hbs ag was never detected. the most probable hypothesis is that these animals were infected with a new virus related to hbv. | 1982 | 7184516 |
| [enhancement of the activity of hepatitis b virus vaccine by association with murabutide]. | murabutide (n-acetyl-muramyl-l-alanyl-d-glutamine-alpha-butylester), an mdp analogue, is a potential adjuvant for human immunization. high levels of specific antibodies were obtained in mouse and guinea-pig following administration with murabutide of low dosages of anti-hepatitis b viral vaccine containing the surface antigen (hbs). the effect of murabutide was enhanced without increasing the level of specific ige by association with suboptimal dosages of aluminium hydroxide. | 1982 | 6218866 |
| no in vivo effect of trisodium phosphonoformate on woodchuck hepatitis virus production. | the efficient in vitro inhibition of hepatitis b virus dna polymerase by trisodium phosphonoformate (pfa, inn: foscarnet sodium) and its low toxicity suggested that pfa could be used as a therapeutic agent for hepatitis b infection. pfa was also found to inhibit woodchuck hepatitis virus (whv) dna polymerase in vitro. as a model to test pfa's eventual effect, chronically whv infected woodchucks were treated with pfa. the animals were treated twice daily in a dosage which gave a minimum serum lev ... | 1982 | 6220563 |
| surface antigenic determinants of mammalian "hepadnaviruses" defined by group- and class-specific monoclonal antibodies. | the hepatitis b-like viruses (human hepatitis b virus, woodchuck hepatitis virus, ground squirrel hepatitis virus, and duck hepatitis b virus) are hepatotropic dna viruses which have been referred to collectively as "hepadnaviruses." using a murine monoclonal antibody (101-2) to the surface antigen of woodchuck hepatitis virus, we have shown that the surface antigens of mammalian hepadnaviruses (hbsag, whsag, and gshsag) are antigenically related via a common determinant (hv/101). furthermore, a ... | 1982 | 6177867 |
| age related resistance to avian leukosis virus. iii. infectious virus, neutralising antibody and tumours in chickens inoculated at various ages. | viraemia and neutralising antibodies were determined in chickens of six age-groups following inoculation with leukosis virus of subgroups a and b at the age of 1 day, and 2, 4, 6, 8 and 10 weeks respectively. the birds were kept in a filtered air positive pressure (fapp) house. a seventh age-group, accommodated in a separate fapp-house, was used as an untreated control. serum samples, received at biweekly intervals between 1-17 weeks post-inoculation, from birds of the groups inoculated at 4, 6, ... | 1982 | 18770194 |
| antigenic and structural relationships of the surface antigens of hepatitis b virus, ground squirrel hepatitis virus, and woodchuck hepatitis virus. | the surface antigens of human hepatitis b (hbsag), ground squirrel hepatitis (gshsag), and woodchuck hepatitis (whsag) viruses were compared serologically, and their major polypeptides were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and tryptic peptide mapping. results showed that both gshsag and whsag are antigenically cross-reactive, that their major pairs of polypeptides have identical mobilities on sodium dodecyl sulfate gels, and that the major polypeptides of gsh ... | 1981 | 6168776 |
| immunization of chimpanzees with hepatitis b virus-derived polypeptides. | previous studies established that the purified polypeptides derived from the 22-nm particles associated with hepatitis b surface antigen (hbsag) produce both humoral and cellular immunity against hbsag in guinea pigs. therefore, the two major polypeptides with molecular weights of 22,000 and 25,000 (p22 and p25, respectively) were isolated, adsorbed to an alum adjuvant, and used to immunize four nonimmune chimpanzees. a vigorous anti-hbs response was observed in all four animals after one inocul ... | 1981 | 7216495 |
| breeding of macaca fascicularis for poliovaccine production. | in our institute cynomolgus monkeys (m. fascicularis) are mainly used for production and control of poliovaccine. in 1974 a small individual breeding colony was started. last year the colony was enlarged with 10 harem groups. based on colony reproduction data, group breeding seems more successful than individual breeding. owing to developments in the production of poliovaccine, a state of total self supply is within reach. however attention must be paid to factors reducing breeding results, comp ... | 1981 | 7227650 |
| virologic control of monkeys used for the production of poliomyelitis virus vaccine. | wild-caught or captive-bred cynomolgus monkeys (macaca fascicularis) used at the national institute of public health for the production of inactivated poliomyelitis virus vaccine are extensively controlled for the presence of antiviral antibodies in their sera. with relatively simple methods of segregation and hygienic measures it seems possible to keep the animals free of infections with certain viruses including herpesvirus simiae and foamy viruses, which is of obvious importance for public he ... | 1981 | 6785124 |
| detection of antibodies to herpesvirus simiae and herpesvirus hominis in nonhuman primates. | sera from nonhuman primates, predominantly macaca species, were assayed by a serum neutralization test for antibodies to antigenically related herpesvirus simiae (b virus) and herpesvirus hominis type 1. the data indicate that there would have been approximately 50% error in the diagnosis of herpesvirus simiae infection if these sera had been tested only against herpesvirus hominis antigen. the role of active guinea pig complement in the serum neutralization test was also evaluated and found to ... | 1981 | 6264222 |
| susceptibility of monkeys to human hepatitis a virus. | a stump-tailed monkey, newly caught and without antibody to hepatitis b virus (hav), was successfully infected with human hav. the following alterations were observed in the monkey's functions: (1) elevation in activities of serum glutamic pyruvic transaminase, lactate dehydrogenase, and its type 5 isoenzyme (electrophoretically the fastest moving); (2) development of antibody to hav; and (3) shedding of hav antigen in feces. the virus isolated from the monkey, designated the hangzhou a-1a strai ... | 1981 | 6267143 |
| fatal herpesvirus infection in patas monkeys and a black and white colobus monkey. | fatal herpesvirus infections were diagnosed in 3 patas monkeys and 1 black and white colobus monkey over a 4-week period. herpesvirus was isolated from 1 patas monkey and from the black and white colobus monkey. both isolates had growth characteristics similar to herpesvirus hominis and herpesvirus simiae. the isolate from the colobus monkey antigenically appeared to be h simiae or h simiae-like, whereas the isolate from the patas monkey could not be conclusively identified with the antisera use ... | 1981 | 6276349 |
| detection of influenza a virus by radioimmunoassay and enzyme-immunoassay from nasopharyngeal specimens. | four-layer (indirect) radioimmunoassay (ria) and enzyme-immunoassay (eia) techniques were developed for the detection of influenza a and b virus in the sonicated nasopharyngeal specimens from patients hospitalized for acute respiratory infection. polystyrene beads (ria) or polystyrene microtiter plates (eia) were used as the solid-phase, guinea pig antivirus immunoglobulins as the catching antibodies, rabbit antivirus immunoglobulins as the secondary antibodies, and 125i-labeled sheep antirabbit ... | 1981 | 7026733 |
| localization and nucleotide sequence of the gene coding for the woodchuck hepatitis virus surface antigen: comparison with the gene coding for the human hepatitis b virus surface antigen. | nucleotide sequence analysis was performed with the maxam--gilbert method on a cloned woodchuck hepatitis virus dna (eco whv dna). the structural gene coding for the envelope protein of the virus was localized on the viral genome in the partially single-stranded region between map positions 91.2 and 71. this gene is composed of 669 nucleotides and can code for a polypeptide of 25,645 daltons. the dna sequence and the deduced amino acid sequence were compared with those of the corresponding gene ... | 1981 | 6946471 |
| woodchuck hepatitis virus in natural woodchuck populations. | woodchuck hepatitis virus (whv) was discovered in serum samples from captive woodchucks (marmota monax) at the penrose research laboratory in december, 1977. whv belongs to the same class of viruses as hepatitis b virus (hbv), the cause of serum hepatitis in man. both appear to be associated with chronic hepatitis and hepatocellular carcinoma in their respective hosts. woodchucks were trapped and blood samples collected to determine the prevalence of whv in natural woodchuck populations. sera fr ... | 1981 | 7241716 |
| viruses similar to hepatitis b virus (icrons). | in 1971, on the basis of the unusual clinical and epidemiologic characteristics of hepatitis b virus, we postulated the existence of a class of viruses that we termed icrons. an increased understanding of the molecular biology of hepatitis b virus resulted in the discovery, by summers and his colleagues, of the woodchuck hepatitis virus. this virus is common in the north american woodchuck (marmota monax) and is associated with primary cancer of the liver in this animal. subsequently similar vir ... | 1981 | 7333575 |
| induction of cell-mediated immunity to hbsag polypeptides. | adult male guinea pigs were immunized with hepatitis b virus polypeptides prepared by triton x-100 solubilization of purified 22-nm hepatitis b surface antigen (hbsag) particles. a virus-specific subunit containing both the 28,000 molecular weight glycoprotein and the 23,000 molecular weight protein stimulated both cell-mediated and humoral immunity. a whole-blood-cell transformation assay additionally showed that the 64,000 molecular weight component of hbsag, previously shown to contain host-s ... | 1981 | 7333794 |
| membranous glomerulopathy associated with hepatitis b core antigen immune complexes in children. | direct immunofluorescence, immunoelectron microscopy, and special immunohistochemical procedures including guinea pig complement fixation, differential elution, and in situ antigen binding were employed in an immunomorphologic analysis of kidney biopsy specimens from 98 children with clinically diagnosed nephrotic syndrome and/or glomerulonephritis (gn). glomerular deposits of hepatitis b virus (hbv) antigens, immunoglobulins, and complement were detected in specimens from 24 children, all serop ... | 1980 | 7350816 |
| virus of pekin ducks with structural and biological relatedness to human hepatitis b virus. | a virus found in the sera of pekin ducks appears to be a new member of the human hepatitis b-like family of viruses. this virus had a diameter of 40 nm and an appearance in the electron microscope similar to that of human hepatitis b virus. the dna genome of the virus was circular and partially single stranded, and an endogenous dna polymerase associated with the virus was capable of converting the genome to a double-stranded circle with a size of ca. 3,000 base pairs. an analysis for viral dna ... | 1980 | 7463557 |
| genetic variation among hepatitis b and related viruses. | hepatitis b virus (hbv) of man has several characteristics that distinguish it from viruses of other groups. these include its ultrastructure, viral dna size and structure, a virion dna polymerase which repairs a single-stranded region in the viral dna, liver tropism, character of persistent infection, and association with hepatitis and hepatocellular carcinoma. recently three other viruses have been found in other animal species that appear to share these characteristics although the viruses ar ... | 1980 | 7013620 |
| humoral and cellular immunity to hepatitis b virus-derived antigens: comparative activity of freund complete adjuvant alum, and liposomes. | complete freud adjuvant, aluminum gel, and liposomes were compared for their ability to enhance the immunogenicity of an intact 22-nm hbsag particle vaccine and an hbsag-derived polypeptide vaccine in guinea pigs. both humoral and cell-mediated immune responses were evaluated. the greatest immune response was obtained with complete freund adjuvant, regardless of the antigen preparation. aluminum gel appeared to be a better adjuvant for 22-nm hbsag particles, but the liposomes rendered polypeptid ... | 1980 | 7014445 |
| isolation, characterization, and comparison of recombinant dnas derived from genomes of human hepatitis b virus and woodchuck hepatitis virus. | the human hepatitis b virus (hbv) and the woodchuck hepatitis virus (whv) are closely related by several criteria and belong to the same class of dna viruses. the dna genomes from these viruses are difficult to obtain in quantities required for biochemical analysis. we have, therefore, cloned these two dnas in the vector lambda gtwes and subcloned into the kanamycin resistance plasmid pa01. comparison of the recombinant dnas with authentic viral dnas by specific hybridization, size, and restrict ... | 1980 | 6246507 |
| detection of primate herpesvirus antibodies including herpesvirus simiae by enzyme immunoassay. | an enzyme immunoassay (eia) was used for the detection of antibodies to herpesvirus hominis type 1 and 2 (hvh-1 and hvh-2), sa8 and herpesvirus simiae (hvb) in human and nonhuman primate sera. optimal assay conditions were approximately the same for hvh-1, hvh-2, and sa8 but different for hvb. the recognized lethality of hvb required studies to determine whether or not inactivated hvb could be used in the eia outside a biohazard safety cabinet. ten percent buffered formalin destroyed infectivity ... | 1980 | 6249690 |
| a virus in beechey ground squirrels that is related to hepatitis b virus of humans. | a virus given the name ground squirrel hepatitis virus (or gshv), with many of the unique characteristics of human hepatitis b virus (hbv), has been found in beechey ground squirrels in northern california. common features include virus morphology, viral dna size and structure, a virion dna polymerase that repairs a single-stranded region in the viral dna, crossreacting viral antigens, and persistent infection with viral antigen continuously in the blood. although similar, gshv and hbv are not i ... | 1980 | 6930677 |