Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| the woodchuck hepatitis b virus infection model for the evaluation of hbv therapies and vaccine therapies. | studies focused on the understanding of the molecular mechanisms involved in recovery or progression to chronicity of hbv may take advantage of natural and experimental models that mimic its properties. this is also of relevance for associated diseases such as cirrhosis and hepatocellulocarcinoma. the eastern woodchuck (marmota monax) infected by the hepadnavirus woodchuck hepatitis b virus (whv) has been applied as a predictive model to support development of new hbv vaccines, antivirals, immun ... | 2010 | 22822718 |
| changes of the receptor-binding properties of influenza b virus b/victoria/504/2000 during adaptation in chicken eggs. | selection of high-growth virus variants of strain b/victoria/504/2000 by serial passage in eggs resulted in three amino acid substitutions, g141e, r162m, and d196y, in the vicinity of the receptor-binding pocket of viral hemagglutinin. virus variants containing the identified amino acid substitutions, individually or in various combinations, were constructed using reverse genetics and analyzed for their receptor-binding properties using glycan microarray platform. three different patterns of vir ... | 2009 | 19766280 |
| seroprevalence of hepatitis b virus and hepatitis c virus among blood donors in nyala, south dar fur, sudan. | the objective of this study was to determine the seroprevalence of hepatitis b virus (hbv) and hepatitis c virus (hcv) infections and the possible risk factors among blood donors in nyala, south dar fur state of western sudan, which has never been studied before. a total of 400 male blood donors were tested for the detection of hbsag and anti-hcv antibodies, (6.25%) were found reactive for hbsag and (0.65%) were reactive for anti-hcv antibodies. the highest seroprevalence (30.8%) was found in th ... | 2009 | 19775459 |
| seropositivity of hepatitis b virus and hepatitis c virus dual infection among blood donors in nyala teaching hospital. | the aim of this study was to determine the seropositivity of hepatitis b virus (hbv) and hepatitis c virus (hcv) dual infection among blood donors in nyala teaching hospital, which is the biggest (400 beds) hospital in great dar fur of western sudan. 400 blood donors were tested serologically for the detection of hbsag and anti-hcv antibodies. only one (0.25%) out of the 400 examined blood donors was detected reactive for both hbsag and anti-hcv antibodies. the study concluded that the seroposit ... | 2009 | 20028507 |
| simian varicella virus in pigtailed macaques (macaca nemestrina): clinical, pathologic, and virologic features. | simian varicella virus (svv; cercopithecine herpesvirus 9) is a naturally occurring herpesvirus of nonhuman primates. here we present the clinical, pathologic, and virologic findings from 2 cases of svv in adult female pigtailed macaques (macaca nemestrina). the initial case presented with hyperthermia and a diffuse inguinal rash which spread centripetally, progressing to vesiculoulcerative dermatitis of the trunk, face, and extremities. at 96 h after presentation, the animal was anorexic and le ... | 2009 | 19887033 |
| protective anti-hepatitis b virus responses in rhesus monkeys primed with a vectored measles virus and boosted with a single dose of hepatitis b surface antigen. | the widely used hepatitis b virus (hbv) vaccine is based on three doses of hepatitis b surface antigen (hbsag) protein. we previously showed that vectored measles viruses (mv) expressing hbsag retain measles vaccine function in monkeys but do not induce a protective anti-hbs response in all animals. we show here that a single dose of hbsag protein following a three-dose vaccination regimen with an optimized hbsag-expressing mv elicits protective anti-hbs responses in all four vaccinated rhesus m ... | 2009 | 19535451 |
| profound antiviral effect of oral administration of miv-210 on chronic hepadnaviral infection in a woodchuck model of hepatitis b. | miv-210 is a prodrug of 3'-fluoro-2',3'-dideoxyguanosine with high oral bioavailability in humans and potent activity against hepatitis b virus (hbv). woodchucks infected with woodchuck hepatitis virus (whv) represent an accurate model of hbv infection that is utilized for evaluation of the efficacy and safety of novel anti-hbv agents. oral administration of miv-210 at 20 or 60 mg/kg of body weight/day induced a rapid virological response in chronically infected woodchucks, reducing serum whv dn ... | 2009 | 19564357 |
| prevalence and phylogenetic analysis of hepatitis b virus among nonhuman primates in taiwan. | hepatitis b virus (hbv) is a public health problem worldwide, and apart from infecting humans, hbv has been found in nonhuman primates. this study investigated the prevalence and phylogenetic analysis of hepatitis b virus (hbv) and hepatitis d virus (hdv) among nonhuman primates in taiwan, an area where human hbv remains endemic. serum samples from 286 captive nonhuman primates (i.e., 32 great apes [pan troglodytes and pongo pygmaeus], 42 gibbons [hylobates sp. and nomascus sp.], and 212 cercopi ... | 2009 | 19746868 |
| detection of clonally expanded hepatocytes in chimpanzees with chronic hepatitis b virus infection. | during a hepadnavirus infection, viral dna integrates at a low rate into random sites in the host dna, producing unique virus-cell junctions detectable by inverse nested pcr (invpcr). these junctions serve as genetic markers of individual hepatocytes, providing a means to detect their subsequent proliferation into clones of two or more hepatocytes. a previous study suggested that the livers of 2.4-year-old woodchucks (marmota monax) chronically infected with woodchuck hepatitis virus contained a ... | 2009 | 19535448 |
| correlation of virus and host response markers with circulating immune complexes during acute and chronic woodchuck hepatitis virus infection. | woodchuck hepatitis virus (whv) is an established model for human hepatitis b virus. the kinetics of virus and host responses in serum and liver during acute, self-limited whv infection in adult woodchucks were studied. serum whv dna and surface antigen (whsag) were detected as early as 1 to 3 weeks following experimental infection and peaked between 1 and 5 weeks postinfection. thereafter, serum whsag levels declined rapidly and became undetectable, while whv dna levels became undetectable much ... | 2009 | 19052077 |
| anionic polymer, poly(methyl vinyl ether-maleic anhydride)-coated beads-based capture of human influenza a and b virus. | an anionic magnetic beads-based method was developed for the capture of human influenza a and b viruses from nasal aspirates, allantoic fluid and culture medium. a polymer, poly(methyl vinyl ether-maleic anhydride) [poly(mve-ma)], was used to endow magnetic beads with a negative charge and bioadhesive properties. after incubation with samples containing human influenza virus, the beads were separated from supernatants by applying a magnetic field. the adsorption [corrected] of the virus by the b ... | 2009 | 19081256 |
| treatment of chronic viral hepatitis in woodchucks by prolonged intrahepatic expression of interleukin-12. | chronic hepatitis b is a major cause of liver-related death worldwide. interleukin-12 (il-12) induction accompanies viral clearance in chronic hepatitis b virus infection. here, we tested the therapeutic potential of il-12 gene therapy in woodchucks chronically infected with woodchuck hepatitis virus (whv), an infection that closely resembles chronic hepatitis b. the woodchucks were treated by intrahepatic injection of a helper-dependent adenoviral vector encoding il-12 under the control of a li ... | 2009 | 19116251 |
| comparative immunogenicity evaluations of influenza a virus m2 peptide as recombinant virus like particle or conjugate vaccines in mice and monkeys. | immunization against m2 peptide, also called m2e, from influenza a virus is an innovative vaccine approach for induction of cross-strain protective immunity. two promising m2 vaccine compositions reported to date are m2 peptide chemically conjugated to carrier proteins or m2 peptide recombinantly expressed on the surface of virus like particles (vlps) of hepatitis b virus core antigen (hbvc). to conduct a head-to-head comparison of these approaches, we constructed two recombinant hbvc vlps expre ... | 2009 | 19146898 |
| ethnic-specific prevalence of hepatitis b/c virus infection in pin-jen, taiwan. | the study aimed to estimate prevalence rate of hepatitis b/c virus infection by three ethnic groups including hakka, minnan, and mainlander in taiwan where there was a high incidence of hepatocellular carcinoma. | 2009 | 20073137 |
| [recombinant adenovirus-mediated expression of 1.2-copy hepatitis b virus dna in three hepatocytes]. | to study hepatitis b virus (hbv) expression in 3 hepatocytes infected with recombinant adenovirus containing 1.2-copy hbv dna.a | 2009 | 19403410 |
| [the characteristics of epidemic influenza a and b virus strains circulating in russia during the 2007-2008 season]. | in 2007-2008 in russia, the epidemic upsurge of influenza morbidity was caused by the active circulation of influenza a(h1n1, a(h3n2), and b viruses. the center for ecology and epidemiology of influenza studied 334 epidemic strains. the results of a comparative study of the svirus specificity of commercial test systems (amplisens influenza virus a/b and amplisens influenza virus a/h5n1) for the polymerase chain reaction diagnosis and virological assays, including virus isolation, revealed their ... | 2009 | 19882900 |
| inhibition of woodchuck hepatitis virus gene expression in primary hepatocytes by sirna enhances the cellular gene expression. | small interfering rna (sirna) has been shown to be active to inhibit the hepatitis b virus gene expression and replication in transient and stable transfection systems. here in primary hepatocytes prepared from naturally woodchuck hepatitis virus (whv)-infected woodchucks, four sirnas targeting the whv pres1, s, c, and x region led to a depletion of whv transcripts and replicative intermediates with different kinetics and a decreased production of viral particles. two sirnas targeting whv s and ... | 2009 | 19064272 |
| vaccination against hepatitis b: the chinese experience. | to review the implementation of mass vaccination of hepatitis b vaccine and its critical role in prevention of hepatitis b virus infection in china. | 2009 | 19187625 |
| primary occult hepadnavirus infection induces virus-specific t-cell and aberrant cytokine responses in the absence of antiviral antibody reactivity in the woodchuck model of hepatitis b virus infection. | although the virological features of serologically silent hepadnaviral primary occult infection (poi) have been relatively well recognized in the woodchuck model of hepatitis b virus infection, the characteristics of accompanying immune responses remain unknown. in this study, the kinetics of woodchuck hepatitis virus (whv)-specific and generalized (mitogen-induced) t-cell proliferative responses and cytokine expression profiles in circulating lymphoid cells and the liver, along with whv-specifi ... | 2009 | 19193791 |
| posttranscriptional regulatory elements enhance antigen expression and dna vaccine efficacy. | in higher eukaryotes, introns are usually required for efficient pre-mrna processing. however, some viruses have alternative approaches involving posttranscriptional regulatory elements (pres) to enhance intronless heterologous gene expression through enabling stability and 3' end formation, and to facilitate the nucleocytoplasmic export of unspliced mrnas. in the current study, we compared the human cytomegalovirus (hcmv) immediate/early (ie) introna, as well as virus-derived pres-the pre of he ... | 2009 | 19388846 |
| lipopolysaccharide-induced innate immune responses in primary hepatocytes downregulates woodchuck hepatitis virus replication via interferon-independent pathways. | our previous studies have shown that toll-like receptor (tlr) ligands, poly i:c and lipopolysaccharide (lps), are able to activate non-parenchymal liver cells and trigger the production of interferon (ifn) to inhibit hepatitis b virus replication in vivo and in vitro. however, little is known about tlr-mediated cellular responses in primary hepatocytes. by the model of woodchuck hepatitis virus (whv) infected primary woodchuck hepatocytes (pwhs), poly i:c and lps stimulation resulted in upregula ... | 2009 | 19573162 |
| characteristics of arbidol-resistant mutants of influenza virus: implications for the mechanism of anti-influenza action of arbidol. | the antiviral drug arbidol (arb), which is licensed in russia for use against influenza, is known to inhibit early membrane fusion events in influenza a and b virus replication. to investigate in more detail the target and mechanism of arb action we generated and studied the characteristics of arb-resistant influenza virus mutants. observations of the arb susceptibility of reassortants between a/singapore/1/57(h2n2) and a/chicken/germany/27(h7n7, "weybridge" strain) and of mutants of the latter ... | 2009 | 19028526 |
| characterization of interleukin 8 in woodchucks with chronic hepatitis b and hepatocellular carcinoma. | the eastern woodchuck, marmota monax, represents a useful animal model to study hepatitis b virus infection in humans. however, immunological studies in this model have been impeded by a lack of basic information about the components of the immune system such as cytokines and chemokines. to clarify the role(s) of interleukin 8 (il-8) in chronic hepatitis b and hepatocellular carcinoma (hcc) in the woodchuck model, we cloned and characterized the woodchuck il-8 cdna and genomic dna. sequence anal ... | 2009 | 18971938 |
| rapid immunity to vaccination with woodchuck hepatitis virus surface antigen using cationic liposome-dna complexes as adjuvant. | complexes of cationic liposomes and non-coding dna (cldc) have shown promise as vaccine adjuvant. using the woodchuck animal model of hepatitis b virus (hbv) infection, the immunogenic effects of cldc were evaluated following vaccination with three doses of woodchuck hepatitis virus surface antigen (whsag) adjuvanted with either cldc or conventional alum and administered intramuscularly (im) or subcutaneously (sc). im vaccination with whsag and cldc elicited antibodies earlier, in more woodchuck ... | 2009 | 19697409 |
| [long-term observation of hepatitis b virus (hbv) replication in new-born tree shrews inoculated with hbv]. | to observe the hepatitis b virus (hbv) replication in the tree shrews that were inoculated with hbv at neonatal period. | 2009 | 19719914 |
| elevated expression of the mir-17-92 polycistron and mir-21 in hepadnavirus-associated hepatocellular carcinoma contributes to the malignant phenotype. | alterations in microrna (mirna) expression in both human and animal models have been linked to many forms of cancer. such mirnas, which act directly as repressors of gene expression, have been found to frequently reside in fragile sites and genomic regions associated with cancer. this study describes a mirna signature for human primary hepatitis b virus-positive human hepatocellular carcinoma. moreover, two known oncomirs--mirnas with known roles in cancer--the mir-17-92 polycistron and mir-21, ... | 2008 | 18688024 |
| pre-clinical evaluation of a novel nanoemulsion-based hepatitis b mucosal vaccine. | hepatitis b virus infection remains an important global health concern despite the availability of safe and effective prophylactic vaccines. limitations to these vaccines include requirement for refrigeration and three immunizations thereby restricting use in the developing world. a new nasal hepatitis b vaccine composed of recombinant hepatitis b surface antigen (hbsag) in a novel nanoemulsion (ne) adjuvant (hbsag-ne) could be effective with fewer administrations. | 2008 | 18698426 |
| [human infection with simian herpes b virus in africa]. | simian herpes b virus or cercopithecine herpesvirus 1 (cehv-1) is enzootic (80% to 100%) in asian monkeys of the genus macaca but is also present in other monkey species. this virus, discovered in 1933, is closely related to human herpesvirus 1 and human herpesvirus 2, responsible respectively for labial and genital herpes. cehv-1 infection is generally asymptomatic or mild in monkeys but in humans it may lead to fulminant encephalomyelitis that has an 80% lethality rate without treatment. infec ... | 2008 | 18684683 |
| chimeric hepatitis b virus core particles carrying an epitope of anthrax protective antigen induce protective immunity against bacillus anthracis. | the major aim of present study is to develop and evaluate chimeric virus-like particles (vlps) displaying a neutralizing epitope of anthrax protective antigen (pa) as a potential vaccine against anthrax. the truncated hepatitis b virus core (hbc) protein (aa 1-144) was used as a carrier, and the 2beta2-2beta3 loop of the pa domain 2 (aa 302-325) which has been shown contains a dominant neutralizing epitope was inserted into the major immunodominant region (mir) of the hbc. the recombinant protei ... | 2008 | 18786589 |
| hepatitis b virus-induced hfgl2 transcription is dependent on c-ets-2 and mapk signal pathway. | fibrinogen-like protein 2 (fgl2)/fibroleukin plays a pivotal role in the pathogenesis of experimental and human fulminant and chronic viral hepatitis. to define the transcription factor(s) and upstream signal transduction pathways involved in the transcription of human fgl2 (hfgl2) in response to hepatitis b (hb) virus, hepatitis b core (hbc), hepatitis b virus s protein (hbs), or hepatitis b virus x protein (hbx) protein, expression plasmids were cotransfected with an hfgl2 promoter luciferase ... | 2008 | 18801734 |
| the history of tumor virology. | in the century since its inception, the field of tumor virology has provided groundbreaking insights into the causes of human cancer. peyton rous founded this scientific field in 1911 by discovering an avian virus that induced tumors in chickens; however, it took 40 years for the scientific community to comprehend the effect of this seminal finding. later identification of mammalian tumor viruses in the 1930s by richard shope and john bittner, and in the 1950s by ludwik gross, sparked the first ... | 2008 | 18829521 |
| a novel approach of prophylaxis to hbv recurrence after liver transplantation. | liver transplantation (lt) in patients with hepatitis b virus (hbv) infection is associated with a high rate of graft loss and poor survival, unless re-infection can be prevented. human hepatitis b immune globulin (hbig) and nucleoside analogues (na) have long been utilized to prevent re-infection. previously, we generated a human monoclonal antibody (mab), hb that recognizes the surface antigen of hepatitis b virus (hbv). we have constructed a secreted version of hb and cloned its genes into re ... | 2008 | 18945464 |
| molecular subtyping of feline immunodeficiency virus from cats in melbourne. | to determine the subtypes of feline immunodeficiency virus (fiv) present in the domestic cat population in melbourne. | 2008 | 18826508 |
| repeated passage of wild-type woodchuck hepatitis virus in lymphoid cells does not generate cell type-specific variants or alter virus infectivity. | woodchuck hepatitis virus (whv), which is closely related to human hepatitis b virus, infects the liver but also invariably establishes persistent infection in the lymphatic system. although the dose of invading virus appears to be the main factor in determining whether whv infection is restricted to the lymphatic system or also engages the liver, the nature of whv lymphotropism remains unclear and a role for a specific lymphotropic variant was not excluded. the availability of woodchuck lymphoc ... | 2008 | 18495768 |
| aberrant lymphocyte activation precedes delayed virus-specific t-cell response after both primary infection and secondary exposure to hepadnavirus in the woodchuck model of hepatitis b virus infection. | the contribution of virus-specific t lymphocytes to the outcome of acute hepadnaviral hepatitis is well recognized, but a reason behind the consistent postponement of this response remains unknown. also, the characteristics of t-cell reactivity following reexposure to hepadnavirus are not thoroughly recognized. to investigate these issues, healthy woodchucks (marmota monax) were infected with liver-pathogenic doses of woodchuck hepatitis virus (whv) and investigated unchallenged or after challen ... | 2008 | 18480439 |
| immunogenicity in mice and rabbits of dna vaccines expressing woodchuck hepatitis virus antigens. | the licensed vaccine against hepatitis b virus (hbv) is an effective means to prevent infection, but is not an effective therapeutic strategy to treat established chronic infections when used alone. in an animal model of chronic hbv infection (the woodchuck experimentally infected with woodchuck hepatitis virus (whv)), the combination of conventional vaccine and potent antiviral drugs has shown promise as a potential therapeutic intervention. this approach might be improved further through the a ... | 2008 | 18556096 |
| antiviral resistance mutations potentiate hepatitis b virus immune evasion through disruption of its surface antigen a determinant. | the hepatitis b virus (hbv) pol gene overlaps the s gene encoding surface antigen (hbsag). it has been reported previously that drug-induced changes in hbsag alter its binding to sera from humans immunized against hbv. we investigate here the changes to specific epitopes in the a determinant (the major target of neutralizing antibody) caused by a number of drug-resistant mutations. | 2008 | 18572757 |
| antiviral effects of lamivudine, emtricitabine, adefovir dipivoxil, and tenofovir disoproxil fumarate administered orally alone and in combination to woodchucks with chronic woodchuck hepatitis virus infection. | adefovir dipivoxil (adv) and tenofovir disoproxil fumarate (tdf) are nucleotide analogs that inhibit the replication of wild-type hepatitis b virus (hbv) and lamivudine (3tc)-resistant virus in hbv-infected patients, including those who are coinfected with human immunodeficiency virus. the combination of adv or tdf with other nucleoside analogs is a proposed strategy for managing antiviral drug resistance during the treatment of chronic hbv infection. the antiviral effect of oral adv or tdf, alo ... | 2008 | 18676881 |
| discrimination of antibody to herpes b virus from antibody to herpes simplex virus types 1 and 2 in human and macaque sera. | the antigenic cross-reactive characteristics of herpes b virus and herpes simplex virus (hsv) type 1 (hsv-1) and hsv-2 are responsible for false-positive diagnoses by serological assays in humans and macaques. in the present study, we developed a fluorometric indirect enzyme-linked immunosorbent assay (elisa) with recombinant herpes b virus glycoprotein d (gd) and hsv-1 and hsv-2 gg (gg-1 and gg-2, respectively) to discriminate between the three primate herpesvirus infections. the secreted form ... | 2008 | 17989200 |
| combination of an antiviral drug and immunomodulation against hepadnaviral infection in the woodchuck model. | the essential role of multispecific immune responses for the control of hepatitis b virus (hbv) infection implies the need of multimodal therapeutic strategies for chronic hbv infection, including antiviral chemotherapy and immunomodulation. this hypothesis was tested in the woodchuck model by a combination of lamivudine pretreatment and subsequent immunizations of woodchucks chronically infected with woodchuck hepatitis virus. the immunizations were performed with dna vaccines or antigen-antibo ... | 2008 | 18160442 |
| quantification of endogenous and exogenous feline leukemia virus sequences by real-time pcr assays. | endogenous retroviruses are integrated in the genome of most vertebrates. they represent footprints of ancient retroviral infection and are vertically transmitted from parents to their offspring. in the genome of all domestic cats, sequences closely related to exogenous felv known as endogenous feline leukemia virus (enfelv), are present. enfelv are incapable of giving rise to infectious virus particles. however, transcription and translation of enfelv have been demonstrated in tissues of health ... | 2008 | 18295344 |
| [the spread and biological properties of epidemic influenza viruses a and b strains circulating in the 2006-2007 season in russia]. | the epidemic upsurge of influenza morbidity in the 2006-2007 season in russia was caused by the active circulation of influenza a(h1n1), a(h3n2) and b viruses. the center for ecology and epidemiology of influenza studied 259 epidemic strains; all the strains were isolated on mdck cell cultures. influenza a(h1n1) viruses (n = 101) were antigenic variants of the references a/new caledonia/20/99 and a/solomon islands/3/06. influenza a(h3n2) viruses (n = 98) were antigenic variants of the references ... | 2008 | 19069788 |
| limited use of centritech lab ii centrifuge in perfusion culture of rcho cells for the production of recombinant antibody. | perfusion cultures of recombinant chinese hamster ovary cells, producing recombinant antibody against the s surface antigen of hepatitis b virus, were carried out in continuous and intermittent mode using a centritech lab ii centrifuge. in the continuous perfusion process, despite the absence of shear stress from the pump head, long-term operation was not possible because of continuously repeated exposure to oxygen limitation and low temperature, as well as shear stress from centrifugal force. i ... | 2008 | 18092799 |
| candidate genes responsible for human hepatocellular carcinoma identified from differentially expressed genes in hepatocarcinogenesis of the tree shrew (tupaia belangeri chinesis). | aim: to explore gene expression profiles during hepatocarcinogenesis of the tree shrew, and to find the genes responsible for human hepatocellular carcinoma (hcc). methods: tree shrews were used as an animal model for hcc induction employing aflatoxin b(1) (afb(1)) alone or afb(1) plus hepatitis b virus (hbv) as etiological factors. gene expression profiles from the tissues of hcc, hcc-surrounding liver tissues (para-hcc) and the corresponding biopsies taken from the same animals before hcc had ... | 2008 | 17714471 |
| development and characterization of a live attenuated influenza b virus vaccine candidate. | a human influenza b/lee/40 virus was cold-adapted by serial passages in embryonated chicken eggs, at progressively lower temperatures, for possible use as a future influenza b vaccine donor strain. temperature sensitive and cold-adapted phenotypes were achieved as a consequence of the adaptation process. it was determined that the virus was attenuated in mice since the replication of the viral genome was significantly reduced in the lung. despite decreased viral replication, the attenuated infec ... | 2008 | 18207290 |
| a case of suspected contact dermatitis in a juvenile cynomolgus monkey (macaca fascicularis). | a 2-year-old male cynomolgus monkey (macaca fascicularis) presented with vesicular dermatitis exhibiting freshly ruptured blisters, crusts, and papules on the extremities and face. | 2008 | 18269530 |
| lethargy, ulcers, bronchopneumonia and death in two aged female bonnet macaques presumed to be caused by cercopithicine herpes virus i. | over the course of 4 weeks, two female aged bonnet macaque (macaca radiata) group-housed females died after the dominant male was removed from the group and the newly dominant male persistently chased, caught and bred all females in the pen. the two aged affected females were observed exhibiting lethargy, dyspnea, with widespread necroulcerative lesions in and around the mouth, muzzle and bridge of their noses. extensive ulcerative glossitis, necrotic bronchopneumonia with intra-nuclear inclusio ... | 2008 | 18269531 |
| the interferon-alpha gene family of marmota himalayana, a chinese marmot species with susceptibility to woodchuck hepatitis virus infection. | the interferon-alpha (ifn-alpha) gene family is an important part of the immune system. recombinant interferon-alpha is widely used to treat viral hepatitis and malignant diseases. marmota himalayana has been found to be susceptible to woodchuck hepatitis virus, a virus genetically related to hepatitis b virus (hbv), and is suitable as an animal model for studies on hbv infection. here, the ifn-alpha gene family of m. himalayana (cwifn-alpha) was characterized. sequence data indicate that the cw ... | 2008 | 17936902 |
| prevention of hepatitis b virus infection in vivo by entry inhibitors derived from the large envelope protein. | 360 million people are chronically infected with the human hepatitis b virus (hbv) and are consequently prone to develop liver cirrhosis and hepatocellular carcinoma. as approved therapeutic regimens-which modulate patients' antiviral defenses or inhibit the viral reverse transcriptase-are generally noncurative, strategies interfering with other hbv replication steps are required. expanding on our demonstration that acylated peptides derived from the large hbv envelope protein block virus entry ... | 2008 | 18297057 |
| prevalence of herpes b virus genome in the trigeminal ganglia of seropositive cynomolgus macaques. | herpes b virus infection is almost asymptomatic in macaques (macaca spp.), which are the natural hosts of this pathogen, but is the cause of high mortality in humans. reactivation of the latent virus in the trigeminal ganglia (tg) results in the shedding of infectious particles into the oral mucosal membrane. saliva contaminated with the reactivated virus from the ganglia of the natural host is considered to be important for viral transmission to humans and other monkeys. in the present study, w ... | 2008 | 18348771 |
| hypermutation of hepatitis b virus genomes by apobec3g, apobec3c and apobec3h. | hepatitis b virus (hbv) is a dna virus that causes liver disease and replicates by reverse transcription of an rna template. previous studies have reported that hbv genomes bearing g-->a hypermutation are present at low frequency in human serum. these mutations are most likely due to the activity of apolipoprotein b mrna-editing enzyme-catalytic polypeptide-like (apobec) cytosine deaminases, cellular proteins known to confer innate immunity against retroviruses by generating lethal hypermutation ... | 2008 | 18420796 |
| primary human hepatocytes are susceptible to infection by hepatitis delta virus assembled with envelope proteins of woodchuck hepatitis virus. | hepatitis b virus (hbv) and hepatitis delta virus (hdv) share the hbv envelope proteins. when woodchucks chronically infected with woodchuck hepatitis virus (whv) are superinfected with hdv, they produce hdv with a whv envelope, whdv. several lines of evidence are provided that whdv infects not only cultured primary woodchuck hepatocytes (pwh) but also primary human hepatocytes (phh). surprisingly, hbv-enveloped hdv (hhdv) and whdv infected phh with comparable efficiencies; however, hhdv did not ... | 2008 | 18495772 |
| rapid emergence of a viral resistant mutant in whv chronically infected woodchucks treated with lamivudine and a pre-s/s cho-derived hepatitis b virus vaccine. | to determine whether the addition of a pre-s/s human vaccine increases the antiviral activity of lamivudine, four woodchucks were treated with a daily dose of 100 mg/kg lamivudine and four 50 microg doses of cho-derived pre-s/s human vaccine. whv dna titres decreased up to two logarithms in three woodchucks. at week 4, in three of the animals, the sequence analysis showed a predominant strain containing a nucleotide change from a to t at position 1696 of domain b of the whv dna polymerase. vacci ... | 2007 | 17531355 |
| persistent occult hepatitis b virus infection: experimental findings and clinical implications. | hepatitis b virus (hbv) is a highly pathogenic virus that causes chronic liver diseases in millions of people globally. in addition to a symptomatic, serologically evident infection, occult persistent hbv carriage has been identified since nucleic acid amplification assays of enhanced sensitivity became introduced for detection of hepadnaviral genomes and their replicative intermediates. current evidence indicates that occult hbv infection is a common and long-term consequence of resolution of a ... | 2007 | 17963292 |
| chimeric adenovirus 5/35 vector containing the clade c hiv gag gene induces a cross-reactive immune response against hiv. | most of the recent hiv studies have focused on the clade b virus subtype. however, it is estimated that half the hiv patients in developing countries are infected with virus belonging to clade c. therefore, a vaccine against hiv clade c is urgently required. in this study, we evaluate the immunogenicity and protective immunity of an adenovirus vector (ad) in balb/c mice and cynomolgus monkeys. we developed an hiv vaccine containing the hiv clade c gag gene using a replication-defective chimeric ... | 2007 | 17386962 |
| tumor necrosis factor activates a conserved innate antiviral response to hepatitis b virus that destabilizes nucleocapsids and reduces nuclear viral dna. | tumor necrosis factor (tnf) is critical for the control of hepatitis b virus (hbv) in the clinical setting and in model systems. tnf induces noncytopathic suppression and clearance of hbv in animal models, possibly through reduction of viral nucleocapsids, but the mechanism is not well described. here, we demonstrate the molecular mechanism and broad host range for tnf action against hbv. we show that tnf rapidly blocks hbv replication by promoting destabilization of preexisting cytoplasmic vira ... | 2007 | 17475655 |
| a vectored measles virus induces hepatitis b surface antigen antibodies while protecting macaques against measles virus challenge. | hepatitis b virus (hbv) acute and chronic infections remain a major worldwide health problem. towards developing an anti-hbv vaccine with single-dose scheme potential, we engineered infectious measles virus (mv) genomic cdnas with a vaccine strain background and expression vector properties. hepatitis b surface antigen (hbsag) expression cassettes were inserted into this cdna and three mvs expressing hbsag at different levels generated. all vectored mvs, which secrete hbsag as subviral particles ... | 2007 | 17634218 |
| serological evidence of hepatitis e virus infection in an indigenous north american population. | hepatitis e virus (hev) infections are thought to be uncommon in north america. recently, hev transmission has been reported following the consumption of deer meat. because deer are closely related to caribou and caribou meat is a staple of the canadian inuit and the american eskimo diet, the present study explored the seroprevalence of hev infection in an isolated canadian inuit community. | 2007 | 17637946 |
| chemoimmunotherapy of chronic hepatitis b virus infection in the woodchuck model overcomes immunologic tolerance and restores t-cell responses to pre-s and s regions of the viral envelope protein. | treatment of chronic hepatitis b virus (hbv) infection could combine potent antiviral drugs and therapeutic vaccines to overcome immunological tolerance and induce the recovery phenotype to protect against disease progression. conventional vaccination of woodchucks chronically infected with the woodchuck hepatitis virus (whv) elicited differential t-cell response profiles depending on whether or not carriers were treated with the potent antiviral drug clevudine (clv), which significantly reduces ... | 2007 | 17652398 |
| therapeutic vaccination in chronic hepatitis b: preclinical studies in the woodchuck model. | interferon-alpha and nucleoside analogues are available for the treatment of chronic hepatitis b virus (hbv) infection but do not lead to a satisfactory result. new findings about the immunological control of hbv during acute infection suggest the pivotal role of t-cell mediated immune responses. several preclinical and clinical trials were undertaken to explore the possibility of stimulating specific immune responses in chronically infected animals and patients by vaccination. however, vaccinat ... | 2007 | 17958643 |
| antiviral effect of orally administered (-)-beta-d-2-aminopurine dioxolane in woodchucks with chronic woodchuck hepatitis virus infection. | (-)-beta-d-2-aminopurine dioxolane (apd) is a nucleoside prodrug that is efficiently converted to 9-(beta-d-1,3-dioxolan-4-yl)guanine (dxg). dxg has antiviral activity in vitro against hepatitis b virus (hbv) but limited aqueous solubility, making it difficult to administer orally to hbv-infected individuals. apd is more water soluble than dxg and represents a promising prodrug for the delivery of dxg. a placebo-controlled, dose-ranging efficacy and pharmacokinetic study was conducted with woodc ... | 2007 | 17606676 |
| prevalence of antibody reaction with cercopithecine herpesvirus 1 antigen in macaca cyclopis, macaca fascicularis, and papio anubis in taiwan. | a total of 284 non-human primate sera were collected between december 2004 and september 2005 and tested by a commercially available dot immunobinding assay for the antibodies to cercopithecine herpesvirus 1, an alphaherpesvirus with high mortality for infected humans. | 2007 | 17976038 |
| natural iminosugar derivatives of 1-deoxynojirimycin inhibit glycosylation of hepatitis viral envelope proteins. | a silkworm (bombyx mori l.) extract known to contain naturally occurring iminosugars, including 1-deoxynojirimycin (1-dnj) derived from the mulberry tree (morus alba l.), was evaluated in surrogate hcv and hbv in vitro assays. antiviral activity of the silkworm extract and one of its purified constituents, 1-dnj, was demonstrated against bovine viral diarrhea virus (bvdv) and gb virus-b (gbv-b), both members of the flaviviridae family, and against woodchuck hepatitis virus (whv) and hepatitis b ... | 2007 | 17978803 |
| development of a novel mouse model to evaluate drug candidates against hepatitis b virus. | woodchuck hepatitis virus (whv)-infected woodchucks have been used for preclinical development of drugs against hepatitis b virus (hbv). however, there is no simple in vivo model to evaluate small amounts of compounds against hbv. to develop such a model, hepad38 cells, in which hbv replication is regulated by tetracycline (tet), were grown as subcutaneous tumours in nude mice. mice developing viraemia were then left untreated or given tet in the drinking water. in some of the mice given tet, it ... | 2007 | 17907379 |
| [common linear b-cell epitopes in human hepatitis b virus core protein and woodchuck hepatitis virus core protein]. | to search for and verify some common b cell epitopes in the core proteins of woodchuck hepatitis virus and human hepatitis b virus. | 2007 | 17711632 |
| vaccination of chicks with live attenuated subtype b avian metapneumovirus vaccines: protection against challenge and immune responses can be unrelated to vaccine dose. | live attenuated subtype b avian metapneumovirus (ampv) vaccines from two different commercial sources (vac 1 and vac 2) were used to vaccinate two groups of day-old specific-pathogen-free chicks. the chicks were challenged at 21 or 49 days of age with a virulent subtype b virus. parameters compared were persistence of vaccine viruses, their ability to induce humoral antibody responses, and the protection they offered against virulent challenge. vac 1 virus was detectable for at least 14 days aft ... | 2007 | 17992934 |
| viral and cellular determinants involved in hepadnaviral entry. | hepadnaviridae is a family of hepatotropic dna viruses that is divided into the genera orthohepadnavirus of mammals and avihepadnavirus of birds. all members of this family can cause acute and chronic hepatic infection, which in the case of human hepatitis b virus (hbv) constitutes a major global health problem. although our knowledge about the molecular biology of these highly liver-specific viruses has profoundly increased in the last two decades, the mechanisms of attachment and productive en ... | 2007 | 17206752 |
| bicistronic woodchuck hepatitis virus core and gamma interferon dna vaccine can protect from hepatitis but does not elicit sterilizing antiviral immunity. | the immunity elicited against nucleocapsid of hepatitis b virus (hbv) and closely related woodchuck hepatitis virus (whv) has been shown to be important in resolution of hepatitis and protection from infection. further, activity of gamma interferon (ifn-gamma), which may directly inhibit hepadnavirus replication, promotes antiviral defense and favors t helper cell type 1 (th1) response, which is seemingly a prerequisite of hbv clearance. in this study, to enhance induction of protective immunity ... | 2007 | 17079319 |
| changes in the titer of anti-b virus antibody in captive macaques (macaca fuscata, m. mulatta, m. fascicularis). | changes in levels of antibody to b virus (cercopithecine herpesvirus 1; bv) were examined in bv-positive macaques by elisa. we observed increases in anti-bv igg titers in a bv-infected cynomolgus monkey after overseas transportation by air and in a rhesus monkey after transfer from an outdoor group cage to an indoor individual cage. although shedding of infectious virus was not examined, the increase in antibody titer suggested reactivation of bv. interestingly, we also found an increase in anti ... | 2007 | 17348300 |
| entry of duck hepatitis b virus into primary duck liver and kidney cells after discovery of a fusogenic region within the large surface protein. | hepatitis b viruses exhibit a narrow host range specificity that is believed to be mediated by a domain of the large surface protein, designated l. for duck hepatitis b virus, it has been shown that the pre-s domain of l binds to carboxypeptidase d, a cellular receptor present in many species on a wide variety of cell types. nonetheless, only hepatocytes become infected. it has remained vague which viral features determine host range specificity and organotropicity. by using chymotrypsin to trea ... | 2007 | 17360753 |
| the woodchuck as an animal model for pathogenesis and therapy of chronic hepatitis b virus infection. | this review describes the woodchuck and the woodchuck hepatitis virus (whv) as an animal model for pathogenesis and therapy of chronic hepatitis b virus (hbv) infection and disease in humans. the establishment of woodchuck breeding colonies, and use of laboratory-reared woodchucks infected with defined whv inocula, have enhanced our understanding of the virology and immunology of hbv infection and disease pathogenesis, including major sequelae like chronic hepatitis and hepatocellular carcinoma. ... | 2007 | 17206759 |
| the role of the woodchuck model in the treatment of hepatitis b virus infection. | experimental studies of animals with chronic hepadnavirus infection could provide valuable insight into optimal therapeutic strategies for individuals with chronic hbv infection. in this review, we focus on the contributions of the woodchuck model to our understanding of hbv biology and on its role in the development of antiviral drug. furthermore, we consider the implications of studies focusing on the natural history of whv infection for the management of hbv and the capacity of treatment to p ... | 2007 | 17981226 |
| immunosuppression reactivates viral replication long after resolution of woodchuck hepatitis virus infection. | resolution of hepatitis b virus (hbv) infection is characterized by coordinated humoral and cellular immune responses. immunity is durable over decades, protecting the host from reinfection and potential activation of residual hbv. woodchucks infected at birth with woodchuck hepatitis virus (whv) cleared viremia and developed antibodies to surface antigen (anti-whs). woodchucks became seronegative for anti-whs 3-6 years later, but in some, whv dna was detected in serum, liver, and/or peripheral ... | 2007 | 17326155 |
| human monoclonal antibody against hepatitis b virus surface antigen (hbsag). | hepatitis b virus (hbv) is one of the main pathogens responsible for hepatitis and hepatocellular carcinoma. human plasma-derived hepatitis b immune globulin (hbig) is being used for prophylactic and liver transplantation currently. however, it may be necessary to replace a hbig with a recombinant one because of limited availability of human plasma with high anti-hbsag antibody titer and possible contamination of human pathogens. a chinese hamster ovary (cho) cell line, hb-c7a, was established w ... | 2007 | 17343928 |
| woodchuck dendritic cells generated from peripheral blood mononuclear cells and transduced with recombinant human adenovirus serotype 5 induce antigen-specific cellular immune responses. | woodchucks infected with the woodchuck hepatitis virus (whv) is the best available animal model for testing the immunotherapeutic effects of dendritic cells (dcs) in the setting of a chronic infection, as woodchucks develop a persistent infection resembling that seen in humans infected with the hepatitis b virus. in the present study, dcs were generated from woodchuck peripheral blood mononuclear cells (wdcs) in the presence of human granulocyte macrophage colony-stimulating factor (hgm-csf) and ... | 2007 | 17385694 |
| evidence-based strategies to improve immunization compliance of postgraduate medical trainees at large academic-medical facilities. | the purpose of this evaluation is to assess the effectiveness of the modifications made by the university of toronto postgraduate medical education to improve medical trainee compliance with the immunization standards set forth in national guidelines, provincial regulations and protocols and university policy. trainee compliance with immunization requirements were evaluated as of january 2003, 2004 and 2005. statistically significant increases in compliance rates for all required immunizations-- ... | 2007 | 17491572 |
| immunomodulation as an option for the treatment of chronic hepatitis b virus infection: preclinical studies in the woodchuck model. | new therapeutic approaches for chronic hepatitis b virus infection based on immunomodulation are now under investigation. the woodchuck model for hepatitis b virus infection has emerged as a useful animal model for the evaluation of such approaches, after developing necessary assays and reagents for immunologic studies in this model. conventional and novel vaccines such as dna vaccines were tested in woodchucks for their ability to induce protective immune responses against challenge infection w ... | 2007 | 17501692 |
| complete-genome analysis of hepatitis b virus from wild-born chimpanzees in central africa demonstrates a strain-specific geographical cluster. | in order to determine whether geographical or species clustering accounts for the distribution of hepatitis b virus (hbv) in subspecies of chimpanzees in africa, four complete chimpanzee hbv (chhbv) genome sequences were obtained from eight hepatitis b surface antigen-positive wild-born chimpanzees from cameroon, republic of congo and gabon. the serological profiles of these chimpanzees corresponded to the acute or chronic highly replicative phase of hbv infection, as confirmed by high plasma hb ... | 2007 | 17872519 |
| differential distribution of antibodies to different viruses in young animals in the free-ranging rhesus macaques of cayo santiago. | the breeding colony of free-ranging rhesus macaques was established in 1938 in cayo santiago (cs) with animals collected in northern india. the seroprevalence to cercopithecine herpesvirus type 1 (b virus) and simian retroviruses has been studied previously. | 2006 | 17214665 |
| a randomized placebo-controlled, dose-finding study of oral lb80380 in hbeag-positive patients with chronic hepatitis b. | lb80380 is potent antiviral agent against hepatitis b virus (hbv) in vitro and in the woodchuck model. it has an excellent preclinical safety profile including lower potential for renal toxicity than adefovir. it is effective against both wild-type and ymdd mutant hbv. lb80380 is converted to its parent drug, lb80331, after oral absorption, and further metabolized to its active form, lb80317. | 2006 | 17302367 |
| hepatitis b virus replication and liver disease progression: the impact of antiviral therapy. | chronic hepatitis b virus (hbv) infection is a serious health issue worldwide. the presence of hbv replication markers--hepatitis b e antigen (hbeag) or hbv dna--is associated with continuing hepatitis activity or intermittent hepatitis flares and subsequent disease progression, including hepatic decompensation and development of liver cirrhosis or hepatocellular carcinoma (hcc). long-term (>10 years) prospective studies in patients >30 years of age have shown that hbeag seropositivity is associ ... | 2006 | 17310811 |
| is the anti-sarcoma and anti-viral cytokine "plasma factor" a novel chicken y-box protein? | a line of research beginning in the early 1960s with the observation that west nile virus and, later, several strains of rabies virus could inhibit the development of the rous sarcoma virus-induced tumor in the wing-web of chicken (a "sarcoma-blockade") eventually culminated in the characterization of a 14-kda circulating anti-sarcoma and anti-viral activity christened "plasma factor" (pf) which, unlike the interferons, inhibited the replication of diverse rna-containing viruses, but not of any ... | 2006 | 17131907 |
| 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 |
| 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 |
| 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 |
| 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 |
| immunology of hdv infection. | hepatitis delta virus (hdv) infection may occur as coinfection with hepatitis b virus (hbv) or as superinfection of a chronically hbv-infected patient. a strong antibody response is mounted, which persists for many years; however, it is not able to modulate the course of infection. in most cases the superinfection takes a chronic course. in patients with inactive disease (hdv pcr negative) an oligospecific t-helper cell immune response and a cytotoxic t-cell response were found, which were absen ... | 2006 | 16903227 |
| clevudine: a potent inhibitor of hepatitis b virus in vitro and in vivo. | clevudine (clv) is a nucleoside analog of the unnatural l-configuration that has potent anti-hepatitis b virus (hbv) activity in vitro and in vivo with a favorable toxicity profile in all species tested. in cell culture, clv is readily phosphorylated to the corresponding 5'-triphosphate form of the compound. the mechanism of action of clv involves the inhibition of the hbv polymerase by clv 5'-triphosphate. in vivo efficacy studies performed in the duck and woodchuck models showed marked, rapid ... | 2006 | 17009935 |
| [inhibition of hepatitis b and duck hepatitis b virus replication by apobec3g]. | to investigate the effect of apolipoprotein b mrna-editing enzyme catalytic polypeptide-like 3g (apobec3g) mediated antiviral activity against hepatitis b virus (hbv) and duck hepatitis b virus (dhbv). | 2006 | 17064466 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| rapid identification of small interfering rna that can effectively inhibit the replication of multiple influenza b virus strains. | influenza b virus is a cause of substantial morbidity and mortality in humans and current vaccination strategies and antiviral drugs only provide limited protection. here, we report the evaluation of small interfering rna (sirna) for repression of viral replication in cultured cells as well as in chicken embryos. several sirnas targeting conserved regions of the virus (in chemically synthesized or plasmid-encoded forms) were found to effectively block the replication of the influenza b virus. th ... | 2006 | 16856616 |
| 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 |
| 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 |
| 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 |
| 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 |