Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| detailed characterization of the peptide binding specificity of five common patr class i mhc molecules. | the chimpanzee (pan troglodytes) is an important model for studying the immune response to several human pathogens, but the study of correlates of immunity has been hindered by the fact that little is known about the epitope-binding specificity of chimpanzee (patr) class i mhc. in the present study we have characterized the peptide binding specificity of several common patr class i molecules. using single amino acid substitution analogs and large peptide libraries, quantitative peptide binding m ... | 2006 | 16791621 |
| primer extension enrichment reaction (peer): a new subtraction method for identification of genetic differences between biological specimens. | we developed a conceptually new subtraction strategy for the detection and isolation of target dna and/or rna from complex nucleic acid mixtures, called primer extension enrichment reaction (peer). peer uses adapters and class iis restriction enzymes to generate tagged oligonucleotides from dsdna fragments derived from specimens containing an unknown target ('tester'). subtraction is achieved by selectively disabling these oligonucleotides by extension reaction using ddntps and a double stranded ... | 2006 | 16790564 |
| genetic recombination for antigenic markers of antigenically different strains of influenza b virus. | incorporation of trypsin in agar overlay or fluid maintenance media resulted in enhancement of plaquing efficiency and replication of influenza b viruses in primary chicken embryo fibroblasts. using this improved technique, recombination was attempted with two serologically distinct strains of influenza b virus, b/lee/40 and b/massachusetts/1/71. after mixed infection, two virus clones were selected and characterized in detail. hemagglutination inhibition and neuraminidase inhibition tests showe ... | 1974 | 16789141 |
| temple monkeys and health implications of commensalism, kathmandu, nepal. | the threat of zoonotic transmission of infectious agents at monkey temples highlights the necessity of investigating the prevalence of enzootic infectious agents in these primate populations. biological samples were collected from 39 rhesus macaques at the swoyambhu temple and tested by enzyme-linked immunosorbent assay, western blot, polymerase chain reaction, or combination of these tests for evidence of infection with rhesus cytomegalovirus (rhcmv), cercopithecine herpesvirus 1 (chv-1), simia ... | 2006 | 16707044 |
| lipid-mediated introduction of hepatitis b virus capsids into nonsusceptible cells allows highly efficient replication and facilitates the study of early infection events. | the hepatitis b virus (hbv) is an enveloped dna virus which is highly infectious in vivo. in vitro, only primary hepatocytes of humans and tupaia belangeri or the novel heparg cell line are susceptible to hbv, but infection is inefficient and study of early infection events in single cells is unsatisfactory. since hepatoma cells replicate the virus efficiently after transfection, this limited infection efficiency must be related to the initial entry phase. here, we describe the lipid-based deliv ... | 2006 | 16699026 |
| identification of novel chimpanzee mhc class i and ii alleles using an improved sequence-based typing strategy. | the chimpanzee (pan troglodytes) is a valuable model for the study of infection with hepatitis c virus and hepatitis b virus, to which only humans and chimpanzees are susceptible. because the cellular immune response plays a crucial role in host defense against these viruses, the analysis of major histocompatibility complex (mhc) (patr) class i and ii allele diversity in chimpanzees is essential for immune response analysis and vaccine development. in the present study, we report a novel, rapid, ... | 2006 | 16698427 |
| characterization of bioactive recombinant woodchuck interleukin-2 amplified by rlm-race and produced in eukaryotic expression system. | woodchucks (marmota monax) infected with woodchuck hepatitis virus (whv) represent a highly valuable laboratory model of hepatitis b virus (hbv) infection, in which molecular, immunological and pathological events occurring in infected humans are adequately reflected. to advance studies on t cell immune responses and propagation of hepadnavirus in t lymphocytes in this animal model, we determined the complete sequence of woodchuck interleukin-2 (wil-2) cdna by utilizing rna ligase-mediated rapid ... | 2006 | 16631932 |
| attachment sites and neutralising epitopes of hepatitis b virus. | hepatitis b virus (hbv), the prototype of the family hepadnaviridae is an organ and species-specific human pathogen. although our knowledge about the molecular biology of this highly liver-specific virus has increased, the mechanism of attachment and entry into its host cell, the differentiated hepatocytes is still enigmatic. numerous potential cellular binding sites for the 3 hbv-surface proteins have been described in the past, but none of them have been proven to be a functional receptor. the ... | 2006 | 16554703 |
| a conserved linear b-cell epitope at the n-terminal region of woodchuck hepatitis virus core protein (whcag). | woodchuck hepatitis virus (whv) is a member of family hepadnaviridae and closely related to hepatitis b virus (hbv). the whv core protein (whcag) is a strongly immunogenic protein and forms virus-like particles. whcag may represent a suitable carrier system for b- and t-cell epitopes. however, the lack of a high expression system for whcag and defined antibodies to detect whcag prevents the use of this carrier system. in the present study, vectors expressing whcag with carboxyl-terminal truncati ... | 2006 | 16513185 |
| [polyethylene glycol-accompanied ion-exchange chromatography to purify recombinant hepatitis b virus surface antigen]. | the dissociation of virus-like particles of hepatitis b surface antigen (hbsag) during the adsorption-desorption on the solid-phase of chromatography is a main challenge for its purification. herein, poly (ethylene glycol) (peg) was applied as an additive during the purification of hbsag from recombinant chinese hamster ovary (cho) cell culture to improve the hbsag recovery and protect its structural assembly. the presence of 1% of peg10000 in the mobile phase of ion-exchange chromatography (iec ... | 2005 | 16468351 |
| identification of hepatitis b virus genome in faecal sample from wild living chimpanzee (pan troglodytes troglodytes) in gabon. | non-invasive faecal sampling in the equatorial forest in gabon allowed the first identification of the hepatitis b virus (hbv-ch(rc170)) genome in samples collected from wild chimpanzees (pan troglodytes troglodytes). the hbv-ch(rcl70)sequence clustered with 100% bootstrap support with previous viral sequences obtained from pan troglodytes subspecies. this is the first evidence of hbv infection in wild apes and confirms that the hbv-like strains thus far characterized in captive apes are directl ... | 2005 | 16461230 |
| altered proteolysis and global gene expression in hepatitis b virus x transgenic mouse liver. | hepatitis b virus x (hbx) is essential for the productive infection of hepatitis b virus (hbv) in vivo and has a pleiotropic effect on host cells. we have previously demonstrated that the proteasome complex is a cellular target of hbx, that hbx alters the proteolytic activity of proteasome in vitro, and that inhibition of proteasome leads to enhanced viral replication, suggesting that hbx and proteasome interaction plays a crucial role in the life cycle and pathogenesis of hbv. in the present st ... | 2006 | 16415018 |
| molecular characterization of woodchuck interleukin 15 (wil-15) and detection of its expression in liver samples of woodchucks infected with woodchuck hepatitis virus (whv). | interleukin 15 (il-15) is a member of the four-helix bundle cytokine family and has t cell growth factor activity. il-15 plays a unique role in both innate and adaptive immune cell homeostasis, particularly for the development of nk cells and cd8+memory cells. it may be useful for stimulation of specific immune responses in chronic viral infection such as hepatitis b virus infection. the woodchuck model is an informative animal model for studies on hepadnavirus infection and therapeutic interven ... | 2006 | 16406557 |
| prevalence of enzootic simian viruses among urban performance monkeys in indonesia. | animal reservoirs are the most important sources of emerging infectious diseases that threaten human populations. global travel and tourism bring ever-increasing numbers of humans into contact with animals, increasing the likelihood of cross species transmission of infectious agents. non-human primates come into contact with humans in a variety of contexts and may harbor infectious agents with zoonotic potential. we investigated the prevalence of infection with enzootic simian viruses among 20 u ... | 2005 | 16359412 |
| hepatitis b virus cccdna clearance: killing for curing? | chronic hepadnavirus infections cause liver damage with ongoing death and regeneration of hepatocytes. in the present study, we set out to quantify the extent of liver turnover by measuring the clonal proliferation of hepatocytes by using integrated viral dna as a genetic marker for individual hepatocyte lineages. liver tissue from woodchucks with chronic woodchuck hepatitis virus (whv) infection was assayed for randomly integrated viral dna by using inverse pcr. serial endpoint dilution of vira ... | 2005 | 16317676 |
| ion-exchange chromatography of hepatitis b virus surface antigen from a recombinant chinese hamster ovary cell line. | about 10% of the chinese population are chronic carriers of hepatitis b virus (hbv). thus, the development of a highly efficient process for the preparation of a vaccine based on a recombinant hepatitis b surface antigen (hbsag) is very important to the chinese national immunization program. to this end, the ion exchange chromatography recovery of cho-hbsag from a recombinant chinese hamster ovary cell line was shown to increase from about 55 to 80% by the addition of 1% poly(ethylene glycol) (p ... | 2005 | 16275291 |
| experimental infection of baboons (papio cynocephalus anubis) with apathogenic and neurovirulent subtypes of herpesvirus papio 2. | cercopithecine herpesvirus 16 (herpesvirus papio 2; hvp2) is an alpha-herpesvirus of baboons (papio spp.) that generally causes minimal to inapparent disease in the natural host species. hvp2 is very closely related genetically and antigenically to cercopithecine herpesvirus 1 (monkey b virus; bv) of macaques, which is well known for its extreme lethality in nonmacaque species including humans. preliminary evidence suggests that a mouse model of hvp2 would be an excellent tool for studying zoono ... | 2005 | 16270898 |
| comparative antigenicity and immunogenicity of hepadnavirus core proteins. | the hepatitis b virus core protein (hbcag) is a uniquely immunogenic particulate antigen and as such has been used as a vaccine carrier platform. the use of other hepadnavirus core proteins as vaccine carriers has not been explored. to determine whether the rodent hepadnavirus core proteins derived from the woodchuck (whcag), ground squirrel (gscag), and arctic squirrel (ascag) viruses possess immunogen characteristics similar to those of hbcag, comparative antigenicity and immunogenicity studie ... | 2005 | 16227284 |
| clevudine inhibits hepatitis delta virus viremia: a pilot study of chronically infected woodchucks. | in a small controlled study, clevudine, a potent inhibitor of hepadnaviruses, including hepatitis b virus and woodchuck hepatitis virus, suppressed hepatitis delta virus (hdv) viremia in chronically infected woodchucks. suppression was correlated with the marked reduction of woodchuck hepatitis virus surface antigen in individual animals, consistent with the concept that repression of surface antigen expression may be a useful antiviral strategy for hdv. | 2005 | 16189132 |
| clevudine for the treatment of chronic hepatitis b virus infection. | chronic hepatitis b virus (hbv) infection is a major health problem that is responsible for < or = 1 million deaths and 500,000 cases of hepatocellular carcinoma worldwide each year. drugs that are currently approved by the fda for the treatment of chronic hbv consist of two groups: the immunomodulators, such as conventional ifn-alpha and pegylated ifn-alpha2a; and nucleoside/nucleotide analogues, such as lamivudine, adefovir dipivoxil and entecavir. however, due to the limitations of these agen ... | 2005 | 16185170 |
| telbivudine: an upcoming agent for chronic hepatitis b. | telbivudine, the prototype member of beta-l-2 -deoxynucleosides, has proven to be safe in in vitro animal and human studies. telbivudine given for 4 weeks resulted in an 8-log reduction of woodchuck hepatitis virus dna, and a 3.8-log reduction of hepatitis b virus dna in human. after 52 weeks of telbivudine treatment there was an approximate 6-log reduction of hepatitis b virus dna levels, hepatitis b virus dna became undetectable by pcr assay in 61% of patients. its antiviral efficacy is signif ... | 2005 | 16107194 |
| use of low-dose chlorpromazine in conjunction with environmental enrichment to eliminate self-injurious behavior in a rhesus macaque (macaca mulatta). | a 7-year-old, captive-bred, female rhesus macaque was placed in a quarantine facility upon arrival at our institution. at release from quarantine, she was observed pawing at and chewing on her left cheek. physical examination revealed ulcerative lesions on the buccal surface of the left cheek. initial differential diagnoses included cercopithecine herpesvirus 1 (b virus)-induced lesions and bacterial infection. dental abnormalities and cheek pouch foreign body were ruled out during the physical ... | 2005 | 16089178 |
| validation of an enzyme-linked immunosorbent assay kit using herpesvirus papio 2 (hvp2) antigen for detection of herpesvirus simiae (b virus) infection in rhesus monkeys. | serologic testing for antibody to monkey b virus (bv) in macaque sera is problematic due to the biohazardous nature of bv antigens. herpesvirus papio 2 (hvp2), a herpesvirus of baboons, is nonpathogenic to humans and is genetically and antigenically more closely related to bv than is human herpes simplex virus 1. this paper describes the results of our in-house laboratory that compared a bv antigen-based enzyme-linked immunosorbent assay (elisa) by commercial testing laboratory and an hvp2-based ... | 2005 | 16089172 |
| a taqman pcr assay using degenerate primers for the quantitative detection of woodchuck hepatitis virus dna of multiple genotypes. | woodchuck hepatitis virus (whv) is a valuable animal model system for studies of hepatitis b virus infection and accurate assessments of whv viral load are necessary in these studies. wild-captured woodchucks that are naturally infected with whv are sometimes used in these studies, however, the sequence variation in whv isolates generally precludes the use of taqman pcr. to facilitate this, we have created a real-time taqman pcr assay for whv using degenerate primers with inosine residues employ ... | 2005 | 16005181 |
| effect of adjuvant on reactogenicity and long-term immunogenicity of the malaria vaccine icc-1132 in macaques. | icc-1132 is a malaria vaccine candidate based on a modified hepatitis b virus core particle (hbc) bearing putative protective epitopes from the circumsporozoite protein (cs) of plasmodium falciparum. while the epitope carrier itself is immunogenic, its potency can be increased by formulation with adjuvants. as a prelude to phase i clinical trials, rhesus macaques were immunised twice with gmp grade icc--1132 in saline or formulated with the adjuvants alhydrogel (alhydrogel) or montanide((r)) isa ... | 2005 | 15998554 |
| antiviral effect of oral administration of tenofovir disoproxil fumarate in woodchucks with chronic woodchuck hepatitis virus infection. | tenofovir disoproxil fumarate (tdf) is a nucleotide analogue approved for treatment of human immunodeficiency virus (hiv) infection. tdf also has been shown in vitro to inhibit replication of wild-type hepatitis b virus (hbv) and lamivudine-resistant hbv mutants and to inhibit lamivudine-resistant hbv in patients and hbv in patients coinfected with the hiv. data on the in vivo efficacy of tdf against wild-type virus in non-hiv-coinfected or lamivudine-naïve chronic hbv-infected patients are lack ... | 2005 | 15980342 |
| pharmacology and pharmacokinetics of the antiviral agent beta-d-2',3'-dideoxy-3'-oxa-5-fluorocytidine in cells and rhesus monkeys. | beta-d-2',3'-dideoxy-3'-oxa-5-fluorocytidine (d-fdoc) is an effective inhibitor of human immunodeficiency virus 1 (hiv-1) and hiv-2, simian immunodeficiency virus, and hepatitis b virus (hbv) in vitro. the purpose of this study was to evaluate the intracellular metabolism of d-fdoc in human hepatoma (hepg2), human t-cell lymphoma (cem), and primary human peripheral blood mononuclear (pbm) cells by using tritiated compound. by 24 h, the levels of d-fdoc-triphosphate (d-fdoc-tp) were 2.8 +/- 0.4, ... | 2005 | 15980324 |
| sequence analysis of the mhc class ii dpb1 gene in chimpanzees (pan troglodytes). | the diversity of the mhc class ii region in non-human primates is a focus of biomedical research because this region plays a crucial role in the recognition of antigens in the immune system. in particular, the chimpanzee [pan troglodytes (patr)], which belongs to the superfamily hominoidea, has been used as a human model for the study of diseases such as human hepatitis c virus (hcv), human hepatitis b virus (hbv) and human immunodeficiency virus (hiv) infections, to which only humans and chimpa ... | 2005 | 15932624 |
| flow cytometric quantification of t cell proliferation and division kinetics in woodchuck model of hepatitis b. | woodchucks infected with woodchuck hepatitis virus (whv) represent the closest natural animal model to study the immunopathogenesis of liver injury caused by essentially noncytopathic, highly human specific hepatitis b virus (hbv). the importance of antiviral t cell response in induction of hepatitis and in control of hbv replication has been demonstrated. however, the understanding of how these responses contribute to the development of different immunomorphological forms of liver disease and t ... | 2005 | 15921160 |
| study of the early steps of the hepatitis b virus life cycle. | hepatitis b virus (hbv) is a human pathogen, causing the serious liver disease. despite considerable advances in the understanding of the natural history of hbv disease, most of the early steps in the virus life cycle remain unclear. virus attachment to permissive cells, fusion and penetration through cell membranes and subsequent genome release, are largely a mystery. current knowledge on the early steps of hbv life cycle has mostly come from molecular cloning, expression of individual genes an ... | 2004 | 15912187 |
| comparative pharmacokinetics of racivir, (+/-)-beta-2',3'-dideoxy-5-fluoro-3'-thiacytidine in rats, rabbits, dogs, monkeys and hiv-infected humans. | racivir is a 50:50 racemic mixture of the (-)- and (+)-beta-enantiomers of 2'-deoxy-3'-thia-5-fluorocytosine (ftc), which is being developed for the treatment of hiv and hepatitis b virus (hbv). the (+)-enantiomer of ftc is approximately 10-20-fold less potent than (-)-ftc, but it selects for a different hiv mutation in human lymphocytes. plasma concentrations from a group of 54 rats, 12 pregnant rabbits and 60 dogs enrolled in large toxicity studies using a wide variety of oral doses, were comp ... | 2005 | 15889534 |
| a pre-s/s cho-derived hepatitis b virus vaccine protects woodchucks from whv productive infection. | we evaluated whether a non-adjuvanted vaccine derived from chinese hamster ovary cells was capable of providing protection against woodchuck hepatitis virus (whv). three woodchucks were vaccinated with four 50-microg doses and challenged with a previously characterized virus isolate (whv197). in all three animals, titre levels of antibodies against hepatitis b surface antigens (anti-hbs) exceeded 10 miu/ml, peaking at 150 miu/ml. challenge resulted in productive acute infection in the two non-va ... | 2005 | 15882525 |
| characterization of duck leucocytes by monoclonal antibodies. | cdnas encoding cd3epsilon, cd4 and the alpha-chain of cd8 of ducks were cloned. monoclonal antibodies against pekin duck cd4 and cd8alpha revealed that the antigens were expressed by the majority of thymocytes and by subpopulations of cd3+ cells in peripheral tissues. cd8alpha cell surface expression was also found on 90% of bursal cells. the b cell specificity of a newly developed mab to the immunoglobulin light-chain (l-chain) was confirmed by double labelling studies with the chicken b-cell c ... | 2005 | 15854685 |
| dimeric zanamivir conjugates with various linking groups are potent, long-lasting inhibitors of influenza neuraminidase including h5n1 avian influenza. | the synthesis, antiviral and pharmacokinetic properties of zanamivir (zmv) dimers 8 and 13 are described. the compounds are highly potent neuraminidase (na) inhibitors which, along with dimer 3, are being investigated as potential second generation inhaled therapies both for the treatment of influenza and for prophylactic use. they show outstanding activity in a 1 week mouse influenza prophylaxis assay, and compared with zmv, high concentrations of 8 and 13 are found in rat lung tissue after 1 w ... | 2005 | 15828835 |
| the tree shrews: useful animal models for the viral hepatitis and hepatocellular carcinoma. | hepatitis b virus (hbv)-induced hepatitis and hepatocellular carcinoma (hcc) are major diseases worldwide. hbv infection and chemical carcinogens such as aflatoxin b1 are known to be two key factors in the development of hcc. animal models for hepatitis and hcc are very useful in the in vivo studies of mechanism involved in the development and prevention of these diseases and the pre-clinical research of drugs for the treatment of these diseases. now, several animals, such as woodchucks, ground ... | 2005 | 15816489 |
| re-analysis of a human hepatitis b virus (hbv) isolate from an east african wild born pan troglodytes schweinfurthii: evidence for interspecies recombination between hbv infecting chimpanzee and human. | according to current estimates, hepatitis b virus (hbv) has infected 2 billion people worldwide and among them, 360 million suffer from chronic hbv infection. except humans, hbv or hbv-like viruses have also been isolated from different species of apes and mammals. although recombination has been described to occur extensively between different genotypes within the human hbv lineage, no recombination event has ever been reported between human and non-human primate hbv sequences. it was our objec ... | 2005 | 15777724 |
| identification and characterization of avihepadnaviruses isolated from exotic anseriformes maintained in captivity. | five new hepadnaviruses were cloned from exotic ducks and geese, including the chiloe wigeon, mandarin duck, puna teal, orinoco sheldgoose, and ashy-headed sheldgoose. sequence comparisons revealed that all but the mandarin duck viruses were closely related to existing isolates of duck hepatitis b virus (dhbv), while mandarin duck virus clones were closely related to ross goose hepatitis b virus. nonetheless, the s protein, core protein, and functional domains of the pol protein were highly cons ... | 2005 | 15708992 |
| korean medicinal plant extracts exhibit antiviral potency against viral hepatitis. | investigation of natural ethnopharmacologic extracts exhibiting antiviral potential may lead to the discovery of new therapeutics for the treatment of chronic viral hepatitis infections. traditional korean medicinal herbs have been identified that exhibit potency against hepatitis b virus (hbv) and hepatitis c virus (hcv) infections. research on the antiviral potential of naturally derived extracts is facilitated through the use of appropriate animal and liver cell culture models for these hepat ... | 2004 | 15673997 |
| pharmacokinetics of the antiviral agent beta-l-3'-fluoro-2',3'-didehydro-2',3'-dideoxycytidine in rhesus monkeys. | beta-l-3'-fluoro-2',3'-didehydro-2',3'-dideoxycytidine (l-3'-fd4c) is a potent and selective antiretroviral nucleoside with activity against lamivudine-resistant human immunodeficiency virus type 1 (hiv-1) and hepatitis b virus (hbv) in vitro. the pharmacokinetics of l-3'-fd4c were characterized in three rhesus monkeys given single intravenous and oral doses. a two-compartment open model was fitted to the plasma and urine data. plasma concentrations declined in a biexponential fashion with an av ... | 2005 | 15673733 |
| herpes b-virus seroreactivity in a colony of macaca mulatta: data from the sabana seca field station, a new specific pathogen-free program. | the demand for b-virus-free animals for biomedical research is increasing, while at the same time the availability of such animals is decreasing. the establishment of specific pathogen-free (spf) breeding macaque colonies is a priority of the national institutes of health. nevertheless, it is well known that seroreactivity to b-virus can be difficult to interpret, particularly as it can vary over time in a single animal. the aim of the present study was to implement a reliable algorithm to exami ... | 2005 | 15667339 |
| hepatitis b virus mutations associated with fulminant hepatitis induce apoptosis in primary tupaia hepatocytes. | hepatitis b virus (hbv) core promoter mutations have been implicated in the pathogenesis of fulminant hepatitis b. due to the limited availability of primary human hepatocytes, the functional characterization of hbv mutants has been performed predominantly in transformed cells, which may not represent ideal model systems for studying virus-cell interactions. we and others have shown that primary hepatocytes of the tree shrew tupaia belangeri support hbv infection and replication. in this study, ... | 2005 | 15660384 |
| frequent infection of hylobates pileatus (pileated gibbon) with species-associated variants of hepatitis b virus in cambodia. | as well as being distributed widely in human populations, hepatitis b virus (hbv) infections occur frequently in chimpanzee, gibbon and other ape populations in sub-saharan africa and south-east asia. to investigate the frequency and genetic relationships of hbv infecting gibbons in cambodia, pileated gibbons (hylobates pileatus) that were originally wild-caught were screened for surface antigen. twelve of 26 (46 %) were positive, of which 11 were positive for hbv dna. phylogenetic analysis of c ... | 2005 | 15659752 |
| clevudine therapy with vaccine inhibits progression of chronic hepatitis and delays onset of hepatocellular carcinoma in chronic woodchuck hepatitis virus infection. | we examined a rational approach to therapy of chronic hepatitis b virus (hbv) infection that utilized the reduction of viral load combined with appropriately timed immune modulation/stimulation. in a placebo-controlled study, chronic woodchuck hepatitis virus (whv) carrier woodchucks received clevudine (l-fmau), previously shown to have especially potent and sustained antiviral activity in woodchucks, for 32 weeks followed by whv surface antigen (whsag) alum-adjuvanted vaccine at 32, 36, 40 and ... | 2004 | 15651753 |
| use of targeted glycoproteomics to identify serum glycoproteins that correlate with liver cancer in woodchucks and humans. | chronic infection with hepatitis b virus (hbv) is associated with the majority of hepatocellular carcinoma (hcc). the diagnosis of hcc is usually made in the late stages of the disease, when treatment options are limited and prognosis is poor. we therefore have developed a method of glycoproteomic analysis in an attempt to discover serum markers that can assist in the early detection of hbv-induced liver cancer. briefly, a comparative method for analysis of oligosaccharides released from serum g ... | 2005 | 15642945 |
| chronic infection with hepatitis b viruses and antiviral drug evaluation in upa mice after liver repopulation with tupaia hepatocytes. | transplantation of primary human hepatocytes and establishment of hepatitis b virus (hbv) infection in immunodeficient urokinase plasminogen activator (upa) transgenic mice was shown. however, the availability of usable primary human hepatocytes is very limited. therefore, alternative and more accessible sources of hepatocytes permissive for hbv infection are highly desirable. here we investigated the potential of primary hepatocytes from the tree shrew tupaia belangeri that were shown to be sus ... | 2005 | 15629507 |
| [in vitro expression of wild type and precore mutant woodchuck hepatitis virus]. | hepatitis b virus (hbv) precore 1896 and 1898 g-->a mutations are regarded as hot spots to study. such mutants have been considered associating with molecular and biological changes of hbv and causing chronic hepatitis and severe forms of hepatitis, including fulminant hepatitis. using oligonucleotide-directed mutagenesis, we have conducted the same point mutations in the precore gene of an infectious clone of woodchuck hepatitis virus (whv-8). transfection of mutant whv dna, 1896 mutant (whv-m1 ... | 1997 | 15619810 |
| phosphorylation analysis of 90 kda heat shock protein within the cytosolic arylhydrocarbon receptor complex. | the arylhydrocarbon receptor (ahr) functions as a ligand-activated transcription factor that regulates the transcription of genes encoding xenobiotic metabolizing enzymes and also mediates most of the toxic effects caused by dioxins and polycyclic aromatic hydrocarbons. the cytosolic ahr complex exists as a transcriptionally cryptic complex, consisting of the 90 kda heat shock protein (hsp90) and the hepatitis b virus x-associated protein 2 (xap2). the posttranslational modifications, especially ... | 2004 | 15581363 |
| alteration of p53 and p21 during hepatocarcinogenesis in tree shrews. | to investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis b virus (hbv) and aflatoxin b(1) (afb(1)) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis. | 2004 | 15534906 |
| woodchuck interleukin-6 gene: structure, characterization, and biologic activity. | woodchuck is an important animal model for studying human hepatitis b virus (hbv) infection. within the cytokine network, interleukin-6 (il-6) plays an important role in immune responses that may lead to viral clearance. to further understand woodchuck il-6 biology, we cloned and characterized the il-6 gene from white blood cells. the complete woodchuck il-6 gene is about 7 kb and consists of five exons and four introns. the il-6 gene organization of the woodchuck is similar to those of the huma ... | 2004 | 15527975 |
| viral infection following kidney transplantation: long-term follow-up in a single center. | viral infections are a leading cause of posttransplantation morbidity and mortality. the use of more potent immunosuppressive agents is responsible in part for the increasing incidence of some viral infections. this study summarized our experience with viral infections in 561 kidney transplant recipients. | 2004 | 15518767 |
| hepatocellular carcinoma in the woodchuck model of hepatitis b virus infection. | the eastern woodchuck ( marmota monax ) harbors a dna virus (woodchuck hepatitis virus [whv]) that is similar in structure and replicative life cycle to the human hepatitis b virus (hbv). like hbv, whv infects the liver and can cause acute and chronic hepatitis. furthermore, chronic whv infection in woodchucks usually leads to development of hepatocellular carcinoma (hcc) within the first 2-4 years of life. the woodchuck model has been important in the preclinical evaluation of safety and effica ... | 2004 | 15508096 |
| a natural asymptomatic herpes b virus infection in a colony of laboratory brown capuchin monkeys (cebus apella). | herpes b virus (bv) infection of macaques persists in the natural host, but is mainly asymptomatic. however, bv can cause fatal disease in humans and in several non-macaque species such as capuchin monkeys (cebus apella). the bv infection described here in a colony of capuchin monkeys was persistent but asymptomatic. initially the infection was detected serologically in five out of seven animals. however, using polymerase chain reaction (pcr) developed specifically for bv, we found the virus in ... | 2004 | 15479559 |
| the win locus involved in activation of the distal n-myc2 gene upon whv integration in woodchuck liver tumors harbors s/mar elements. | woodchuck hepatitis virus (whv) and the woodchuck (marmota monax) are models for hepatocellular carcinoma (hcc) induced by hepatitis b virus (hbv). in woodchuck liver tumors, the n-myc2 proto-oncogene is frequently activated by whv integration either close to the gene or in the b3n and win downstream loci, located 10 and 150 kb from n-myc2, respectively. a scaffold/matrix attachment region (s/mar) regulative element was shown to be in b3n, possibly mediating activation of the upstream n-myc2 gen ... | 2004 | 15476869 |
| persistence of isolated antibodies to woodchuck hepatitis virus core antigen is indicative of occult infection. | antibodies against virus nucleocapsid (anticore) normally accompany hepadnaviral hepatitis but they may also occur in the absence of symptoms and other serological indicators of the infection. this situation can be encountered following a clinically and serologically unapparent exposure to hepatitis b virus (hbv) or after recovery from hepatitis b. in this study, woodchucks inoculated with woodchuck hepatitis virus (whv) were investigated to determine the relationship between anticore detection ... | 2004 | 15382154 |
| a dose-finding study of once-daily oral telbivudine in hbeag-positive patients with chronic hepatitis b virus infection. | current therapy for chronic hepatitis b is suboptimal as a result of limited durable response rates, cumulative viral resistance, and/or poor tolerability. telbivudine has potent antiviral activity against hepatitis b virus (hbv) in vitro and in the woodchuck model and has a promising preclinical safety profile. in this first clinical study of telbivudine, safety, antiviral activity, and pharmacokinetics were assessed in 43 adults with hepatitis b e antigen-positive chronic hepatitis b. this pla ... | 2004 | 15349912 |
| [serial pathologic changes in livers of tree shrews and macaca assamensises infected with human hepatitis b virus]. | to serially observe the pathologic changes in livers of tree shrews and macaca assamensises infected with hhbv. | 2003 | 15340568 |
| antigenic alteration of influenza b virus associated with loss of a glycosylation site due to host-cell adaptation. | effects of host-cell adaptation of the hemagglutinin (ha) protein were evaluated by the analyses of four pairs of recent influenza b field isolates, each pair consisting of an madin darby canine kidney (mdck)- and an embryonated chicken egg-derived isolates from the same clinical specimen. among the isolates examined, all of the mdck-derived isolates retained glycosylation site at amino acid 197 on the ha1 molecule, whereas three egg-derived isolates lost it. antigenic difference in the ha molec ... | 2004 | 15332284 |
| adenovirus-based gene therapy during clevudine treatment of woodchucks chronically infected with woodchuck hepatitis virus. | interferon-alpha (ifn-alpha) is a potent suppressor of hepatitis b virus (hbv) replication in the hbv-transgenic mouse, depleting virus replication intermediates from infected hepatocytes via pathways mediated by interferon-gamma (ifn-gamma) and tumor necrosis factor alpha (tnf-alpha). it has also been hypothesized that cytokines induce curing of infected hepatocytes via non-cytolytic pathways during resolution of transient hepadnavirus infections. we have therefore evaluated therapy of chronic ... | 2004 | 15327895 |
| suppression of lamivudine-resistant b-domain mutants by adefovir dipivoxil in the woodchuck hepatitis virus model. | adult woodchucks (marmota monax) chronically infected with woodchuck hepatitis virus (whv) were treated orally with lamivudine (15 mg/kg per day) for 57 weeks. after 20 weeks of treatment a 2-3 log reduction in serum whv dna was detected. serum titers of whv then increased gradually, in the presence of lamivudine treatment, reaching pre-treatment values by week 40. viral recrudescence was associated with development of mutations in the b domain of the whv polymerase gene. mutations observed in t ... | 2004 | 15302140 |
| genomic dna double-strand breaks are targets for hepadnaviral dna integration. | integrated hepadnaviral dna in livers and tumors of chronic hepatitis b patients has been reported for many years. in this study, we investigated whether hepatitis b virus dna integration occurs preferentially at sites of cell dna damage. a single i-scei homing endonuclease recognition site was introduced into the dna of the chicken hepatoma cell line lmh by stable dna transfection, and double-strand breaks were induced by transient expression of i-scei after transfection of an i-scei expression ... | 2004 | 15258290 |
| structure of pre-s2 n- and o-linked glycans in surface proteins from different genotypes of hepatitis b virus. | the middle-sized (m) surface proteins of hepatitis b virus (hbv) and other orthohepadnaviruses contain a conserved n-glycan in their pre-s2 domain, which is essential for the secretion of viral particles. recently, we also found o-glycans in the pre-s2 domain of m protein from woodchuck hepatitis virus (whv) and hbv genotype d. since the o-glycosylation motif is not conserved in all genotypes of hbv, the glycosylation patterns of hbv genotypes a and c were analysed. pre-s2 (glyco)peptides were r ... | 2004 | 15218190 |
| effect of a combination of clevudine and emtricitabine with adenovirus-mediated delivery of gamma interferon in the woodchuck model of hepatitis b virus infection. | our aim was to evaluate the antiviral effect of a combination of two nucleoside reverse transcriptase inhibitors, emtricitabine (ftc) and clevudine (l-fmau), with the addition of an adenovirus-driven delivery of recombinant gamma interferon (ifn-gamma) in the woodchuck model of hepatitis b virus infection. six woodchuck hepatitis virus (whv)-infected woodchucks received l-fmau (10 mg/kg) plus ftc (30 mg/kg) intraperitoneally for 8 weeks; six other animals received in addition an intravenous inje ... | 2004 | 15215126 |
| a novel class of phosphonate nucleosides. 9-[(1-phosphonomethoxycyclopropyl)methyl]guanine as a potent and selective anti-hbv agent. | 9-[1-(phosphonomethoxycyclopropyl)methyl]guanine (pmcg, 1), representative of a novel class of phosphonate nucleosides, blocks hbv replication with excellent potency (ec(50) = 0.5 microm) in a primary culture of hepg2 2.2.15 cells. it exhibits no significant cytotoxicity in several human cell lines up to 1.0 mm. it does not inhibit replication of human immunodeficiency virus (hiv-1) or herpes simplex virus (hsv-1) at 30 microm. many purine base analogues of 1 also exhibit inhibitory activity aga ... | 2004 | 15139764 |
| specific detection and identification of herpes b virus by a pcr-microplate hybridization assay. | herpes b virus dna was specifically amplified by pcr, targeting the regions that did not cross-react with herpes simplex virus (hsv). the amplified products, which were shown to be highly genetic polymorphisms among herpes b virus isolates, were identified by microplate hybridization with probes generated by pcr. the products immobilized in microplate wells were hybridized with the biotin-labeled probes derived from the smhv strain of herpes b virus. the amplified products derived from the smhv ... | 2004 | 15131142 |
| b-virus and free-ranging macaques, puerto rico. | in puerto rico, risk for transmission of b-virus from free-ranging rhesus monkeys to humans has become a serious challenge. an incident with an injured rhesus monkey, seropositive for b-virus, resulted in inappropriate administration of antiviral postexposure prophylaxis. this incident underscores the importance of education about risks associated with interactions between humans and nonhuman primates. | 2004 | 15109420 |
| cpg oligodeoxynucleotides improve the response to hepatitis b immunization in healthy and siv-infected rhesus macaques. | the development of an immunogenic vaccine against hepatitis b virus (hbv) is particularly important for hiv-infected patients since shared epidemiological risks result in hiv-infected subjects having a high incidence of hbv, and coinfection with hbv increases the occurrence of hepatotoxicity with antiretroviral therapy. although hbv vaccination is recommended to all hiv-positive patients, its efficacy in these patients is reduced. | 2004 | 15096802 |
| adoptive transfer of immunity: a new strategy to interfere with severe hepatitis virus reinfection after woodchuck liver transplantation. | the effective transfer of humoral immunity to hepatitis b virus was first demonstrated after clinical and experimental bone marrow transplantation. this strategy is now evaluated in the woodchuck transplantation model, in which protection from reinfection can be tested. | 2004 | 15087755 |
| inhibition of cellular proteasome activities enhances hepadnavirus replication in an hbx-dependent manner. | the x protein (hbx) of the hepatitis b virus (hbv) is not essential for the hbv life cycle in vitro but is important for productive infection in vivo. our previous study suggests that interaction of hbx with the proteasome complex may underlie the pleiotropic functions of hbx. with the woodchuck model, we demonstrated that the x-deficient mutants of woodchuck hepatitis virus (whv) are not completely replication defective, possibly behaving like attenuated viruses. in the present study, we analyz ... | 2004 | 15078938 |
| synergistic interaction between aflatoxin b1 and hepatitis b virus in hepatocarcinogenesis. | chronic hepatitis b virus (hbv) infection and dietary exposure to aflatoxin b1 (afb1), two of the major risk factors in the multifactorial aetiology of hepatocellular carcinoma (hcc), co-exist in those countries with the highest incidences of and the youngest patients with this tumour, raising the possibility of a synergistic carcinogenic interaction between the two agents. experimental studies in hbv-transgenic mice and woodchucks infected with woodchuck hepatitis virus were the first to show a ... | 2003 | 14986813 |
| the influenza b virus nonstructural ns1 protein is essential for efficient viral growth and antagonizes beta interferon induction. | we analyzed the functions of the influenza b virus nonstructural ns1-b protein, both by utilizing a constructed mutant virus (delta ns1-b) lacking the ns1 gene and by testing the activities of the protein when expressed in cells. the mutant virus replicated to intermediate levels in 6-day-old embryonated chicken eggs that contain an immature interferon (ifn) system, whereas older eggs did not support viral propagation to a significant extent. the delta ns1-b virus was a substantially stronger in ... | 2004 | 14747551 |
| low doses of hepadnavirus induce infection of the lymphatic system that does not engage the liver. | woodchuck hepatitis virus (whv), which is closely related to human hepatitis b virus and is considered to be principally hepatotropic, invades the host's lymphatic system and persists in lymphoid cells independently of whether the infection is symptomatic and serologically evident or concealed. in this study, we show, with the woodchuck model of hepatitis b, that hepadnavirus can establish an infection that engages the lymphatic system, but not the liver, and persists in the absence of virus ser ... | 2004 | 14747538 |
| cis-acting sequences that contribute to the synthesis of relaxed-circular dna of human hepatitis b virus. | synthesis of the relaxed-circular (rc) genome of hepadnaviruses is a multistep process that requires template switching during reverse transcription. studies of duck hepatitis b virus indicated the presence of cis-acting sequences, distinct from the donor and acceptor sequences for the template switches, which contribute to the synthesis of rc dna. however, knowledge about cis-acting requirements distinct from the donor and acceptor sites for human hepatitis b virus (hbv) was lacking. in this st ... | 2004 | 14694095 |
| inhibitory effect of adefovir and lamivudine on the initiation of hepatitis b virus infection in primary tupaia hepatocytes. | adefovir dipivoxil and lamivudine are two safe and efficacious drugs licensed for the treatment of chronic hepatitis b virus (hbv) infection. both drugs inhibit the viral polymerase, resulting in a profound suppression of virus production. blocking the viral polymerase may also affect the initiation of hbv infection, because hbv virions harbor a partially double-stranded genome and productive infection requires completion of viral plus-strand dna synthesis with subsequent formation of covalently ... | 2003 | 14647052 |
| alteration of the p53 gene during tree shrews' hepatocarcinogenesis. | to detect the expression and variation of the p53 gene in hepatocarcinogenesis of tree shrews induced by hepatitis b virus (hbv) and aflatoxin b1 (afb1). | 2003 | 14627531 |
| complete nucleotide sequence and phylogenetic analyses of hepatitis b virus isolated from two pileated gibbons. | we analyzed full-length sequence of hepatitis b virus (hbv) recovered from two pileated gibbons (hylobates pileatus) originally born in east asia. two animals possessed a viral genome of 3182 nt in length with a 33 nt deletion in the pre-s1 region, and designated hbv pg-makiko and hbv pg-yohko, respectively. both sequences had 65-90% similarity to type a-g of human hbv isolates. phylogenetic analysis demonstrated that both isolates were distinct from the human and other nonhuman primate hbv isol ... | 2003 | 14618082 |
| hepatic cirrhosis occurring in a young woodchuck (marmota monax) due to vertical transmission of woodchuck hepatitis virus (whv). | histologic and clinicopathologic findings of a woodchuck (marmota monax) vertically infected with woodchuck hepatitis virus (whv) are presented. the liver exhibits marked cirrhotic changes, which is characteristic of the pre-transformation phase of whv. at necropsy, the woodchuck exhibited ascites and the liver had a grossly nodular appearance. microscopically, focal hepatocyte necrosis and inflammatory cells were observed in midzonal and periportal areas in the liver. in macchiavellos stained s ... | 2003 | 14610377 |
| [differentially expressed genes in hepatocellular carcinoma of tree shrew induced by different factors]. | previous studies on differentially expressed genes in hepatocellular carcinoma (hcc) used to perform with para-cancerous tissues as normal control. however, the para-cancerous tissue of hcc is actually abnormal because they frequently contain hepatitis, cirrhosis, hyperplastic nodules or foci, etc. in order to explore the molecular mechanism and the responsible genes for hepatocarcinogenesis, through applying the hcc model of tree shrew (tupaia belangeri chinensis), this study was designed to co ... | 2003 | 14558942 |
| geographic and species association of hepatitis b virus genotypes in non-human primates. | infection with hepatitis b virus (hbv) has been detected in human populations throughout the world, as well as in a number of ape species (pan troglodytes, gorilla gorilla, gibbons [nomascus and hylobates species] and pongo pygmaeus). to investigate the distribution of naturally occurring hbv infection in these species and other african old world monkey species (cercopithecidae), we screened 137 plasma samples from mainly wild caught animals by polymerase chain reaction (pcr) using several of hi ... | 2003 | 14517090 |
| comparison of the pathogenesis of newcastle disease virus and influenza b virus in chicken embryos. | 1960 | 14425334 | |
| development of resistance of influenza b virus to polysaccharides. | algal polysaccharide obtained from carrageenin protects 80 to 100 percent of chicken embryos against fatal infections with the lee strain of influenza virus. this report describes the rapid emergence of a stable variant of this virus which is resistant to the protective action of this polysaccharide. | 1958 | 13615309 |
| enzymatic variants of influenza virus. ii. effect of environmental factors on enzymatic characteristics of a variant of influenza b virus. | the rate of elution of the variant virus from chicken rbc is progressively decreased as the temperature of incubation is increased above 25 degrees c. the activity of the parent virus, on the other hand, is increased as the temperature is increased up to 40 degrees c. the major cause of the decreased activity of the variant at temperatures above 2s degrees c. is an inhibition of the variant enzyme rather than its inactivation. the activity of the variant enzyme is stimulated in the presence of s ... | 1958 | 13587849 |
| the influence of cortisone on experimental viral infection. iil effects on certain dynamics of influenza virus increase. | the administration of cortisone to chicken embryos infected with influenza b virus results in (a) an initial inhibition of viral synthesis and (b) an eventual increase in the final yield of virus attained. increased yields of virus are attained regardless of the number of viral particles in the infecting inoculum or the proportion of particles which are infective. changes in the distribution ratios of allantoic fluid and intramembrane virus are effected by cortisone only as the secondary result ... | 1957 | 13481248 |
| enzymatic variants of influenza virus. i. isolation and characterization of slowly reacting enzymatic variants of influenza b virus. | slowly reacting enzymatic variants of the lee strain of influenza b virus were isolated by the serial application of a technique which concentrated the fraction of the virus population obtained by slow elution followed by passage of this fraction at high dilution in chicken embryos. the variants were stable upon serial passage in chicken embryos and did not differ significantly from the parent virus in any of the characteristics tested other than those relating to the virus enzyme. enzymatically ... | 1957 | 13439115 |
| isolation of b virus (herpes group) from the central nervous system of a rhesus monkey. | while passaging a recently isolated strain of poliomyelitis virus through a rhesus monkey, another virus was procured from its central nervous system. after intracerebral inoculation, the virus produced meningoencephalitis in monkeys, cotton rats, hamsters, guinea pigs, and rabbits; after intracutaneous inoculation a necrotic skin lesion was produced in the monkey and rabbit and this was often followed by myelitis. the virus could also be passed in newborn mice less than 48 hours old and in chic ... | 1954 | 13286422 |
| reproduction of influenza viruses; quantitative investigations with particle enumeration procedures on the dynamics of influenza a and b virus reproduction. | influenza a and b virus reproduction in the allantoic membrane of the intact chicken embryo was studied quantitatively with particle enumeration procedures. virus particles were enumerated on the basis of two independent properties; capacity to infect and to cause hemagglutination. the infective property of influenza b virus (lee) was even more unstable than that of influenza a virus (pr8). inactivation occurred at a constant logarithmic rate which was independent of the concentration of particl ... | 1955 | 13263486 |
| effect of b virus (strain no.1) in the syrian hamster. | 1952 | 12996750 | |
| molecular characterization of cd28 and cytotoxic t-lymphocyte-associated antigen 4 (ctla-4) of woodchuck (marmota monax). | eastern woodchuck (marmota monax) became an important animal model to study the immunological processes in hepatitis b virus infection. to facilitate further study of t-cell responses in this model, we cloned and sequenced the cdnas of woodchuck cd28 and cytotoxic t-lymphocyte-associated antigen 4 (ctla-4), which play important roles for the regulation of t-cell activation by delivering the costimulation signals. according to the deduced amino-acid sequences, woodchuck cd28 showed a similarity o ... | 2003 | 12956876 |
| induction of antibodies to the pres region of surface antigens of woodchuck hepatitis virus (whv) in chronic carrier woodchucks by immunizations with whv surface antigens. | one goal of therapeutic vaccinations against chronic hepatitis b virus infection is to stimulate the b-cell responses to viral surface antigens in chronic carriers. here we investigated the induction of antibody responses to hepadnaviral surface antigens in the woodchuck model, with emphasis on the vaccination of woodchucks chronically infected with woodchuck hepatitis virus (whv). | 2003 | 12927927 |
| pre-s1 antigen-dependent infection of tupaia hepatocyte cultures with human hepatitis b virus. | the susceptibility of the tree shrew tupaia belangeri to human hepatitis b virus (hbv) has been demonstrated both in vivo and in vitro. in this study, we show that purified hbv infects primary t. belangeri hepatocyte cultures in a very specific manner, as detected by hbv covalently closed circular dna, mrna, hbv e antigen, and hbsag production. a monoclonal antibody (mab), ma18/7, directed against the pre-s1 domain of the large hbs protein, which has been shown to neutralize infectivity of hbv f ... | 2003 | 12915565 |
| [human hepatitis b virus infection of tree shrews and macaca assamensis in vivo]. | to examine sensitivity of the tree shrews and macaca assamensis to human hepatitis b virus (hhbv) by serologic methods. | 2003 | 12884835 |
| ultrasonography in the study of hepatocellular carcinoma in woodchucks chronically infected with whv. | the woodchuck hepatitis virus (whv)/woodchuck system is studied as animal model of human hepatocellular carcinoma (hcc) induced by chronic hepatitis b virus infection. the aim of the present study was the evaluation of ultrasound (us) liver examination in woodchuck as a routine method to detect hcc nodules and to follow their growth. sixteen woodchucks were included in the study. us liver examination was carried out in all animals using a 5 mhz convex scanner. macroscopic and microscopic examina ... | 2003 | 12869286 |
| comparison of tamarins and marmosets as hosts for gbv-b infections and the effect of immunosuppression on duration of viremia. | gbv-b virus is a close relative to hepatitis c virus (hcv) that causes hepatitis in tamarins, and thus, is an attractive surrogate model for hcv. in this study, we demonstrate that the host range of gbv-b extends to the common marmoset with an infection profile similar to that observed for tamarins. marmoset hepatocytes were susceptible to in vitro infection with gbv-b. virus was efficiently secreted into the medium, and approximately 25% of hepatocytes were positive for ns3 staining. in an atte ... | 2003 | 12832204 |
| activation and inhibition of cellular calcium and tyrosine kinase signaling pathways identify targets of the hbx protein involved in hepatitis b virus replication. | human hepatitis b virus (hbv) hbx protein is a multifunctional protein that activates cellular signaling pathways and is thought to be essential for viral infection. woodchuck hbv mutants that lack hbx are unable to replicate in vivo or are severely impaired. hbv replication in hepg2 cells, a human hepatoblastoma cell line, is stimulated 5- to 10-fold by hbx protein. we have utilized the hepg2, hbx-dependent hbv replication system to study the effects of activators and inhibitors of cytosolic ca ... | 2003 | 12829810 |
| fatal herpes simplex infection in a group of common marmosets (callithrix jacchus). | an outbreak of classical herpetic infection causing vesicoulcerative stomatitis in a family group (eight animals) of callithrix jacchus is described. in all eight infected animals, human herpesvirus 1 (hhv-1) was identified as the causative agent. this was confirmed by histologic, immunohistologic, and molecular biologic investigations, as well as by virus isolation. the clinical picture, the macroscopic appearance, and the histologic results indicated a herpes infection as the cause of mortalit ... | 2003 | 12824512 |
| the tree shrews: adjuncts and alternatives to primates as models for biomedical research. | the tree shrews are non-rodent, primate-like, small animals. there is increasing interest in using them to establish animal models for medical and biological research. this review focuses on the use of the tree shrews in in vivo studies on viral hepatitis, hepatocellular carcinoma (hcc), myopia, and psychosocial stress. because of the susceptibility of the tree shrews (tupaia belangeri) and their hepatocytes to infection with human hepatitis b virus (hbv) in vivo and in vitro, these animals have ... | 2003 | 12823622 |
| inactivated parapoxvirus ovis (orf virus) has antiviral activity against hepatitis b virus and herpes simplex virus. | it is known that some viruses are able to induce vigorous immune reactions. this study shows that inactivated parapoxvirus ovis (orf virus), strain d1701 (ppvo), induces an autoregulatory cytokine response that involves the upregulation of il-12, il-18, ifn-gamma and other t helper 1-type cytokines and their subsequent downregulation, which is accompanied by induction of il-4. an increase in il-10 expression was also found in the livers of ppvo-treated mice. ppvo protects mice from lethal herpes ... | 2003 | 12810878 |
| replication and transmission of influenza viruses in japanese quail. | quail have emerged as a potential intermediate host in the spread of avian influenza a viruses in poultry in hong kong. to better understand this possible role, we tested the replication and transmission in quail of influenza a viruses of all 15 ha subtypes. quail supported the replication of at least 14 subtypes. influenza a viruses replicated predominantly in the respiratory tract. transmission experiments suggested that perpetuation of avian influenza viruses in quail requires adaptation. swi ... | 2003 | 12788625 |
| antiviral activity and pharmacokinetics of 1-(2,3-dideoxy-2-fluoro-beta-l-glyceropent-2-enofuranosyl)cytosine. | 1-(2,3-dideoxy-2-fluoro-beta-l-glyceropent-2-enofuranosyl)cytosine (l-2'-fd4c) is an l-nucleoside analogue with both anti-human immunodeficiency virus (hiv) and anti-hepatitis b virus (hbv) activity with median effective concentrations of 0.12 microm in peripheral blood mononuclear cells and 0.002 microm in hepg2-2.2.15 cells, respectively. the purpose of this study was to examine the antihepadnavirus potency and pharmacokinetics of l-2'-fd4c in vivo. hbv-transgenic mice treated intraperitoneall ... | 2003 | 12760868 |
| complete sequence and comparative analysis of the genome of herpes b virus (cercopithecine herpesvirus 1) from a rhesus monkey. | the complete dna sequence of herpes b virus (cercopithecine herpesvirus 1) strain e2490, isolated from a rhesus macaque, was determined. the total genome length is 156,789 bp, with 74.5% g+c composition and overall genome organization characteristic of alphaherpesviruses. the first and last residues of the genome were defined by sequencing the cloned genomic termini. there were six origins of dna replication in the genome due to tandem duplication of both oril and oris regions. seventy-four gene ... | 2003 | 12743273 |
| overexpression of hepatitis b virus surface antigens including the pres1 region in a serum-free chinese hamster ovary cell line. | current hepatitis b virus (hbv) vaccines consist of preparations of recombinant hbv major surface antigen (sag) and are protective in about 90-95% of vaccinated subjects. in improved vaccines, the frequency of nonresponders to the classical vaccine could be reduced by including additional epitopes from the pres-domains of the middle and large surface antigens. in this report, the development and characterization of a cho cell line for hbsag, expressing major, middle, and large antigens are descr ... | 2003 | 12729726 |