| inhibition of bovine immunodeficiency virus by anti-hiv-1 compounds in a cell culture-based assay. | the bovine immunodeficiency virus (biv) and human immunodeficiency virus types 1 and 2 (hiv-1 and -2) are members of the lentivirus genus of retroviruses. although dna sequences of these viruses have diverged considerably, the biv genome organization, function of structural and regulatory genes, and replication cycle are very similar to that of hiv-1, making biv a potentially useful model to study compounds with anti-hiv-1 activity. a cell culture-based antiviral assay was developed to test comp ... | 1996 | 8955850 |
| bovine lentivirus induces early transient b-cell proliferation in experimentally inoculated cattle and appears to be pantropic. | bovine immunodeficiency-like virus (biv) was first isolated in 1972 (m. j. vandermaaten et al., j. natl. cancer inst. 49:1649-1657, 1972). much work has been done on the molecular characterization of biv in studies using the original biv r29 isolate; however, r29 is believed to be attenuated since it no longer causes either mononuclear cell number increases or detectable enlargement of lymphatic nodules in experimentally infected cattle. the host cell tropism and changes in host peripheral blood ... | 1997 | 8985394 |
| enhancement of monocyte migration and phagocytosis by the bovine immunodeficiency-like virus gag proteins. | supernatants from bovine immunodeficiency-like virus (biv)-infected cells have been previously shown to affect monocyte random migration, chemotaxis, phagocytosis, and antibody-dependent cell-mediated cytotoxicity (adcc) in vitro. the experiments in this report demonstrate that the biv gag (core) proteins can enhance monocyte random migration, chemotaxis, and phagocytosis. supernatants from biv-infected cells contained 10-30 and 30-50 kda proteins, which significantly (p < 0.05) increased monocy ... | 1997 | 8989206 |
| targeting the tat-binding site of bovine immunodeficiency virus tar rna with a shape-selective rhodium complex. | the tat-binding site of the bovine immunodeficiency virus tar rna hairpin has been targeted by rh(phen)2phi3+ (phen = phenanthroline, phi = 9,10-phenanthrenequinone diimine), a photochemical probe of rna tertiary structure. the primary site cleaved by the rhodium complex, upon photoactivation, is u24, a base which participates in the novel base triple (with bases a13 and u10) characteristic of this folded rna. delta-rh(phen)2phi3+ binds to this site with an affinity of 2 x 10(6) m-1. upon mutati ... | 1997 | 9222507 |
| bovine immunodeficiency virus and analogies with human immunodeficiency virus. | after describing the results of biv research during the past years experimental data are presented which indicate that biv does not cause any clinical symptoms after infection and that no correlation exists with the other widely spread retrovirus in the bovine, the bovine leukosis virus (blv). since contact obviously did not lead to a horizontal transmission it is suggested that transmission occurs, as in the cat, vertically from dam to offspring. it was also found that a long period of time aft ... | 1999 | 10232381 |
| detection of proviral dna of bovine immunodeficiency virus in bovine tissues by polymerase chain reaction (pcr) and pcr in situ hybridization. | in this study, experiments were designed to investigate the distribution of bovine immunodeficiency virus (biv) proviral dna in the tissues and cells of infected calves by solution-phase polymerase chain reaction (sp-pcr) and pcr in situ hybridization (pcr-ish). total dna samples extracted from tissues of 10 biv-infected and 5 uninfected calves were amplified by sp-pcr with the primers directed to the biv conserved pol gene segment. the identity of the sp-pcr product was confirmed by southern hy ... | 1997 | 9325232 |
| rna recognition by a bent alpha-helix regulates transcriptional antitermination in phage lambda. | a novel rna recognition motif is characterized in an arginine-rich peptide. the motif, derived from lambda transcriptional antitermination protein n, regulates an rna-directed genetic switch. its characterization by multidimensional nuclear magnetic resonance (nmr) demonstrates specific rna-dependent folding of n- and c-terminal recognition helices separated by a central bend. the biological importance of the bent alpha-helix is demonstrated by mutagenesis: binding is blocked by substitutions in ... | 1997 | 9335528 |
| detection of bovine immunodeficiency virus antibodies in cattle by western blot assay with recombinant gag protein. | a western blot assay using purified recombinant bovine immunodeficiency virus gag protein has been developed for detection of bovine immunodeficiency virus antibodies in bovine serum samples. the test was standardized with known bovine immunodeficiency virus positive and negative bovine serum samples and the monoclonal antibody to gag protein. both naturally and experimentally infected cattle sera demonstrated positive test results. the result of western blot assay was compared with polymerase c ... | 1997 | 9376421 |
| distribution of bovine immunodeficiency virus in the organs of experimentally infected cows. | the distribution of bovine immunodeficiency virus (biv) in the organs of experimentally infected cows was investigated by use of nested polymerase chain reaction (pcr). two cows (nos. 1 and 2) experimentally infected with biv were alive without any clinical symptoms of biv infection for 28 months. viral and proviral genomes of biv were continuously detected from peripheral blood leukocytes in those cows by nested pcr. proviral genomes of biv were also detected in liver, lung, and spleen cells in ... | 1997 | 9433017 |
| sequence data analysis reveals a relationship between lsr2, the recombinant fusion protein mimicing m. leprae and vif of bovine immunodeficiency virus (biv). | in the course of computer simulation study looking for active sites for the interaction between mhc ii and t7--a 12 residue long peptide of lsr2--a recombinant fusion protein mimicing the native bacillus m.leprae--an interesting relationship between the antigenicity of lsr2 and vif of bif has come to light. computer analysis study has revealed this stretch of residue from 36 to 48 of lsr2 is highly antigenic. the experimental observation seems to confirm the role of this 12 residue peptide in an ... | 1997 | 9440006 |
| natural and experimental bovine immunodeficiency virus infection in cattle. | since 1989, the lsu dairy herd, with its high seroprevalence of biv, was recognized to have a high incidence of common diseases that reduced the economic viability of the dairy. the herd had a high percentage of cows with encephalitis associated with depression and stupor, alteration of the immune system associated with secondary bacterial infections, and chronic inflammatory lesions of the feet and legs. the occurrence of disease problems was associated with the stresses of parturition and earl ... | 1997 | 9071752 |
| food animal and poultry retroviruses and human health. | in summary, studies reported to date have largely failed to demonstrate human infection with animal and poultry retroviruses or an association between human diseases and these viruses. a number of studies, most of them serologic, have attempted to demonstrate human infection with these viruses. the lack of antibodies in apparently exposed groups of persons suggests an absence of infection. however, another possible explanation is that humans may be immunologically unresponsive to infection with ... | 1997 | 9071753 |
| detection of bovine immunodeficiency-like virus infection in experimentally infected calves. | detection of biv virus infection by serological means, pcr and virus isolation in experimentally infected calves is described. viral sequences were specifically detected by pcr in peripheral blood mononuclear cells (pbmcs), with primer systems located in the gag, pol and tat regions of the viral genome. an enzyme-linked oligosorbent assay (elosa) in microtiter plates is described, for the detection of pcr products, the sensitivity of which was shown to be comparable to that of membrane hybridiza ... | 1998 | 9505976 |
| infection of bovine immunodeficiency virus and bovine leukemia virus in water buffalo and cattle populations in pakistan. | a survey of antibodies to bovine immunodeficiency virus (biv) known as bovine lentivirus and bovine leukemia virus (blv) was conducted with samples from water buffalo and cattle populations in pakistan. a total of 370 water buffaloes and 76 cattle were tested, and 10.3% and 15.8%, respectively, were found positive for anti-biv p26 antibodies determined by western blotting, while 0.8% of water buffaloes and no cattle were positive for anti-blv antibodies determined by immunodiffusion test. biv-se ... | 2000 | 10770609 |
| equine infectious anemia virus transactivator is a homeodomain-type protein. | lentiviral transactivator (tat) proteins are essential for viral replication. tat proteins of human immunodeficiency virus type 1 and bovine immunodeficiency virus form complexes with their respective rna targets (tat responsive element, tar), and specific binding of the equine anemia virus (eiav) tat protein to a target tar rna is suggested by mutational analysis of the tar rna. structural data on equine infectious anemia virus tat protein reveal a helix-loop-helix-turn-helix limit structure ve ... | 1998 | 9545368 |
| prevalence of bovine immunodeficiency-like virus in bulls as determined by serology and proviral detection. | we found the rate of bovine immunodeficiency-like virus (biv) infection among bulls to be 9.6% using serology and 12.6% when tested by the polymerase chain reaction (pcr) for the presence of biv provirus in peripheral blood leukocytes. previously, we determined the frequency of biv infection among the general dairy cow population in ontario to be 5.5% based on serological analysis. apparently, serological testing detects only 77% of biv-infected bulls. since almost a quarter of biv-infected bull ... | 1998 | 9684054 |
| altering the context of an rna bulge switches the binding specificities of two viral tat proteins. | the bovine immunodeficiency virus (biv) tat protein binds with high affinity to its tar rna site through a large set of specific rna-protein contacts whereas human immunodeficiency virus (hiv) tat makes relatively few contacts to hiv tar and requires the assistance of a cellular protein to bind with high affinity. the two tar sites are structurally very similar, but biv tat appears unable to make the same set of high-affinity contacts to hiv tar. to determine the basis of this discrimination, we ... | 1998 | 9692971 |
| effects of long-term infection with bovine immunodeficiency virus and/or bovine leukemia virus on antibody and lymphocyte proliferative responses in cattle. | immune responses were examined in cattle between 3-5 years after experimental inoculation with bovine immunodeficiency virus (big) and/or bovine leukemia virus (blv). lymphocyte proliferative responses to con a or to allogeneic lymphocytes with foreign major histocompatibility complex molecules (allo mhc) were determined by 3h-thymidine incorporation assays. antigen-specific antibody and lymphocyte proliferative responses were measured following vaccination with tetanus toxoid (tt) and bovine he ... | 1998 | 9730220 |
| recombinant jembrana disease virus proteins as antigens for the detection of antibody to bovine lentiviruses. | jembrana disease virus (jdv) is a recently identified bovine lentivirus causing an acute severe disease syndrome in banteng cattle (bos javanicus) and a milder disease syndrome in bos taurus cattle in indonesia. the virus is closely related genetically to the previously identified bovine lentivirus, bovine immunodeficiency virus (biv). recombinant clones were produced which contained the capsid (ca) and transmembrane (tm) subunits of the respective gag and env open reading frames of jdv. the pro ... | 1998 | 9763127 |
| investigation of the cellular tropism of bovine immunodeficiency-like virus. | bovine immunodeficiency-like virus (biv) was first isolated from an animal showing transient leucocytosis, lymphadenopathy, lesions in the central nervous system and progressive weakness and emaciation. similar signs are observed in other immunosuppressive lentiviral infections. biv, like other lentiviruses, has been isolated from peripheral blood mononuclear cells and lymphoid tissue of infected animals. however, the in vivo cellular tropism of biv remains unclear although initial studies indic ... | 1998 | 9769070 |
| failure to detect bovine immunodeficiency virus contamination of stud bull spermatozoa, blood leukocytes, or semen leukocytes in samples supplied by artificial insemination centers. | to determine whether bovine immunodeficiency virus (biv) infection could be detected in spermatozoa, blood leukocytes, or semen leukocytes from stud bulls in artificial insemination centers. | 2000 | 10895906 |
| seroprevalence to bovine immunodeficiency virus and lack of association with leukocyte counts in italian dairy cattle. | we report herein on the first serological detection of antibodies to bovine immunodeficiency virus (biv) in italy. according to criteria of a stratified-random sampling of dairy cattle reared in the parma area (a province in the po valley, northern italy), sera from 3166 cows belonging to 272 herds were collected. in addition, sera of 138 bulls from eight artificial-insemination (ai) centres were sampled. seventy-eight cows (2.5%) from 16 herds (5.8%) and seven bulls (5.1%) from two ai centres w ... | 1998 | 9879588 |
| infection of rabbits with r29 strain of bovine immunodeficiency virus: virulence, immunosuppression, and progressive mesenteric lymphadenopathy. | to assess the value of bovine immunodeficiency virus (biv) infection as a model for human immunodeficiency virus (hiv) infection in man, we studied the impairment of certain immunologic functions in new zealand white rabbits experimentally infected with an uncloned virulent isolate of the virus, biv r29. serum samples were tested by western blot for the presence and persistence of antibody production. the t- and b-lymphocyte function was studied by evaluation of the blastogenic responsiveness to ... | 1998 | 9918407 |
| the antibody response of cattle infected with bovine immunodeficiency virus to peptides of the viral transmembrane protein. | the development of the antibody response to peptides of the transmembrane glycoprotein of bovine immunodeficiency virus (biv) was followed over a period of 50 weeks in six cattle experimentally infected with the biv(fl112) isolate. antibody was detected by an enzyme immunoassay using either a linear or a cyclized peptide with structural features common to an immunodominant region of other lentiviruses. the assay was specific for biv, detecting antibody in bovine sera to biv(fl112) or biv(r29) bu ... | 1999 | 9934707 |
| adaptive recognition in rna complexes with peptides and protein modules. | recently, progress has been made towards the structural characterization of the novel folds of rna-bound arginine-rich peptides and the architecture of their peptide-binding rna pockets in viral and phage systems. these studies are based on an approach whereby the peptide and rna components are minimalist modular domains that undergo adaptive structural transitions upon complex formation. such complexes are characterized by recognition alignments in which the tertiary fold of the rna generates b ... | 1999 | 10047585 |
| structural model of the hiv-1 tat(46-58)-tar complex. | the trans-activator protein (tat) of human immunodeficiency virus type 1 (hiv-1) binds to an uridine-rich bulge of an rna target (tar; trans-activation responsive element) predominantly via its basic sequence domain. the structure of the tat(46-58)-tar complex has been determined by a novel modeling approach relying on structural information about one crucial arginine residue and crosslink data. the strategy described here solely uses this experimental data without additional "modeling" assumpti ... | 1998 | 10052624 |
| bovine immunodeficiency virus in experimentally infected rabbit: tropism for lymphoid and nonlymphoid tissues. | the bovine immunodeficiency virus (biv)/new zealand (oryctolagus cuniculus) rabbit model was used to study events that underlie the early and chronic stages of viral replication, routes and time course of viral dissemination and the distribution of the virus in the lymphoid. nonlymphoid and mucosa associated tissues. the results indicated that biv, a lentivirus with genetic relatedness to the hiv, induced changes of clinical (anorexia, weight loss, muscular wasting, diarrhea, hypoalgesia, tortic ... | 2001 | 11131038 |
| development of a western blot assay for detection of bovine immunodeficiency-like virus using capsid and transmembrane envelope proteins expressed from recombinant baculovirus. | a 120-amino-acid polypeptide selected from the transmembrane protein region (ttm) and the major capsid protein p26 of bovine immunodeficiency-like virus (biv) were expressed as fusion proteins from recombinant baculoviruses. the antigenic reactivity of both recombinant fusion proteins was confirmed by western blot with bovine and rabbit antisera to biv. biv-negative bovine sera and animal sera positive for bovine syncytial virus and bovine leukemia virus failed to recognize the recombinant fusio ... | 1999 | 10066648 |
| natural selection of the pol gene of bovine immunodeficiency virus. | genetic variability is a salient feature of lentiviruses, contributing to the pathogenesis of these viruses by enabling them to persist in the host and to resist anti-retroviral treatment. bovine immunodeficiency virus (biv), a lentivirus of unknown pathology, infects cattle in the united states and worldwide. genetic diversity of biv that is associated with naturally infected cattle is not well studied. we examined the genetic diversity and natural selection of a segment of the biv pol gene amp ... | 1999 | 10069955 |
| aids campaigner on trial for testing vaccine on people. | the founder of the indian health organisation, ishwar gilada, was arrested in april 1999 for administering manisyl, a bovine immunodeficiency virus vaccine, to aids patients in 1994 (3 of these patients have since died). the investigation into gilada's practices began in september 1995, when a patient took gilada to court and the drug controller of india testified that gilada had not received the mandatory clearance to conduct patient trials using manisyl. the developer of the vaccine, us-base ... | 1999 | 10335804 |
| seroprevalence of bovine immunodeficiency virus in dairy and beef cattle herds in korea. | infection of bovine immunodeficiency virus (biv), a lentivirus, is thought to sporadically occur throughout the world, but seroepidemiological surveys concerning the incidence of biv are limited and have not been undertaken in korea. a total of 266 sera from different twenty dairy (holstein) and twenty-six korean native beef (hanwoo) farms of the south-western part of korea was analyzed for the presence of anti-biv antibodies by western blotting. thirty five percent and 33% of dairy and beef cat ... | 1999 | 10379949 |
| serological evidence of an australian bovine lentivirus. | recombinant 26 kda capsid (ca) proteins of bovine lentiviruses, bovine immunodeficiency virus (biv) and jembrana disease virus (jdv), were expressed in escherichia coli and utilised as antigens for an enzyme-linked immunosorbent assay (elisa) and a western immunoblot (wib) procedure for the detection of antibody in dairy cattle in western australia. a total of 690 serum samples, 30 from each of 23 farms, were tested by elisa with a jdv ca protein antigen, and antibody was detected in 3.8% (p<0.0 ... | 1999 | 10501174 |
| detection of bovine immunodeficiency virus dna in the blood and semen of experimentally infected bulls. | five 18- to 24-month-old bulls were inoculated with either a cell suspension containing bovine immunodeficiency virus (biv-fl112; 3 bulls) or a biv-free cell suspension (2 bulls). blood and semen specimens were collected once a week for 14 weeks, and seroconversion was confirmed by indirect immunofluorescent antibody (ifa) testing. the presence of biv in blood and semen was determined by virus isolation and/or polymerase chain reaction (pcr) assays. antibodies to biv were detected in the 3 exper ... | 1999 | 10591494 |
| anchoring an extended htlv-1 rex peptide within an rna major groove containing junctional base triples. | the rex protein of the human t cell leukemia virus type 1 (htlv-1) belongs to a family of proteins that use arginine-rich motifs (arms) to recognize their rna targets. previously, an in vitro selected rna aptamer sequence was identified that mediates mrna transport in vivo when placed in the primary binding site on stem-loop iid of the rex response element. we present the solution structure of the htlv-1 arginine-rich rex peptide bound to its rna aptamer target determined by multidimensional het ... | 1999 | 10647177 |
| jembrana disease virus tat can regulate human immunodeficiency virus (hiv) long terminal repeat-directed gene expression and can substitute for hiv tat in viral replication. | jembrana disease virus (jdv) is a bovine lentivirus genetically similar to bovine immunodeficiency virus; it causes an acute and sometimes fatal disease in infected animals. this virus carries a very potent tat that can strongly activate not only its own long terminal repeat (ltr) but also the human immunodeficiency virus (hiv) ltr. in contrast, hiv tat cannot reciprocally activate the jdv ltr (h. chen, g. e. wilcox, g. kertayadnya, and c. wood, j. virol. 73:658-666, 1999). this indicates that i ... | 2000 | 10684286 |
| a viral transmembrane recombinant protein-based enzyme-linked immunosorbent assay for the detection of bovine immunodeficiency virus infection. | the expression of bovine immunodeficiency virus (biv) truncated transmembrane envelope protein (designated hereafter ttm) in insect cells has been described previously (abed, y., st-laurent, g., zhang, h., jacobs, r.m., archambault, d., 1999. development of a western blot assay for detection of bovine immunodeficiency-like virus using capsid and transmembrane proteins expressed from recombinant baculovirus. clin. diagn. lab. immunol. 6, 168-172). in this study, a ttm-based enzyme-linked immunoso ... | 2000 | 10716344 |
| natural transplacental infection of dairy calves with bovine immunodeficiency virus and estimation of effect on neonatal health. | many experimental infection studies with bovine immunodeficiency virus (biv) have been conducted, but neither virus transmission under natural conditions nor longitudinal clinical effects of naturally occurring infections in non-experimental populations are well explored. we tested the hypotheses that biv is transmitted across the placenta during gestation and that intragestionally infected calves are at increased risk of neonatal disease. a cohort of 59 dairy cows on one farm were enrolled at p ... | 2000 | 10718493 |
| functional differences between human and bovine immunodeficiency virus tat transcription factors. | transcriptional transactivation of the human immunodeficiency virus type 1 (hiv-1) long terminal repeat (ltr) promoter element by the essential viral tat protein requires recruitment of positive transcription elongation factor b (p-tefb) to the viral tar rna target. the recruitment of p-tefb, which has been proposed to be necessary and sufficient for activation of viral gene expression, is mediated by the highly cooperative interaction of tat and cyclin t1, an essential component of p-tefb, with ... | 2000 | 10775603 |
| clinical response and immunomodulation following experimental challenge of calves with type 2 noncytopathogenic bovine viral diarrhea virus. | eight calves between 16 and 18 weeks of age that were seronegative to bovine viral diarrhea virus (bvdv), bovine leucosis virus and bovine immunodeficiency-like virus were infected (day 0) intranasally with the type 2 noncytopathogenic canadian 24515 field isolate of bvdv in order to evaluate the effect of bvdv infection on certain clinical, hematological and immunological parameters. all virus-exposed animals developed fever and showed a significant (p < 0.05, 0.01 or 0.001) drop in the number ... | 2000 | 10779200 |
| viral contamination of embryos cryopreserved in liquid nitrogen. | despite the worldwide application of embryo-freezing technology as the means of preserving germplasm of mammalian species, there is no information available on the possible transmission of infectious agents to cryopreserved embryos via contaminated liquid nitrogen (ln). recently, it has been reported that new methods of cryopreservation which employ ultrarapid freezing or vitrification require direct contact between the freezing medium containing oocytes or embryos and liquid phase nitrogen (lpn ... | 2000 | 10788310 |
| antigenic and genetic stability of bovine immunodeficiency virus during long-term persistence in cattle experimentally infected with the biv(r29) isolate. | experimental infection of cattle with bovine immunodeficiency virus (biv) is characterized by persistent, low levels of virus replication in the absence of clinical disease. a virus neutralization (vn) assay was developed to examine the role of vn antibodies in controlling virus replication in cattle experimentally infected with the biv(r29) isolate of biv. all animals developed vn antibody, but there was no correlation between vn titres and restriction of virus replication in vivo. biv infectio ... | 2000 | 10811930 |
| binding of tat to tar and recruitment of positive transcription elongation factor b occur independently in bovine immunodeficiency virus. | transcriptional transactivators (tat) from many lentiviruses interact with their cognate transactivation response rna structures (tar) to increase rates of elongation rather than initiation of transcription. for several of them, the complex of tat and a species-specific cyclin t1 must be formed before the binding to tar can occur with high affinity and specificity. in sharp contrast, tat from the bovine immunodeficiency virus (biv) binds to its tar without the help of the cyclin t1. this binding ... | 2000 | 10846086 |
| bovine immunodeficiency virus in relation to embryos fertilized in vitro. | the association of bovine immunodeficiency virus (biv) with embryos derived by in vitro fertilization from oocytes of experimentally infected heifers or oocytes/embryos exposed to the virus in vitro was investigated. using a nested-pcr assay, proviral dna of biv was not detected in follicular fluid or in embryos derived from biv-infected donors. in vitro exposure of oocytes to biv during maturation or insemination with biv-infected semen resulted in zona pellucida-intact embryos testing negative ... | 2001 | 11767012 |
| cloning of the bovine immunodeficiency virus gag gene and development of a recombinant-protein-based enzyme-linked immunosorbent assay. | an enzyme-linked immunosorbent assay (elisa) was established for the rapid detection of specific bovine immunodeficiency virus (biv) antibodies in cattle, using recombinant gag protein as an antigen. the gag coding region from biv was cloned into an expression vector, pqe32, which expressed high levels of recombinant protein from escherichia coli. the elisa was standardized by a checkerboard titration against known biv-positive and -negative sera from cattle and a monoclonal antibody to the gag ... | 2000 | 10882651 |
| seroprevalence of bovine immunodeficiency virus and bovine leukemia virus in draught animals in cambodia. | since bovine immunodeficiency virus (biv), known as bovine lentivirus, has been detected in dairy and beef cattle in various countries around the world, a prevalence study of antibodies to biv and bovine leukemia virus (blv) was conducted in draught animals in five provinces in cambodia, where protozoan parasite infections were suspected in some animals. to clarify the status of draught animals including haryana, brahman, mixed-breed, local breed cattle and muscle water buffaloes, a total of 544 ... | 2000 | 10945301 |
| rna bulge entropies in the unbound state correlate with peptide binding strengths for hiv-1 and biv tar rna because of improved conformational access. | for the binding of peptides to wild-type hiv-1 and biv tar rna and to mutants with bulges of various sizes, changes in the deltadelta g values of binding were determined from experimental k d values. the corresponding entropies of these bulges are estimated by enumerating all possible rna bulge conformations on a lattice and then applying the boltzmann relationship. independent calculations of entropies from fluctuations are also carried out using the gaussian network model (gnm) recently introd ... | 1998 | 9801321 |
| viral infections and bovine mastitis: a review. | this review deals with the role of viruses in the aetiology of bovine mastitis. bovine herpesvirus 1, bovine herpesvirus 4, foot-and-mouth disease virus, and parainfluenza 3 virus have been isolated from milk from cows with clinical mastitis. intramammary inoculations of bovine herpesvirus 1 or parainfluenza 3 virus-induced clinical mastitis, while an intramammary inoculation of foot-and-mouth disease virus resulted in necrosis of the mammary gland. subclinical mastitis has been induced after a ... | 2002 | 12119136 |
| lectins from bulbs of the chinese daffodil narcissus tazetta (family amaryllidaceae). | the isolation of three lectins with similar n-terminal amino acid sequences from the bulbs of the chinese daffodil narcissus tazetta was achieved. the isolation protocol involved ion exchange chromatography on deae-cellulose, affinity chromatography on mannose-agarose, and fast protein liquid chromatography-gel filtration on superose 12. the lectins were all adsorbed on mannose-agarose and demonstrated a single band with a molecular weight of 13 kda in sds-polyacrylamide gel electrophoresis and ... | 2000 | 11012085 |
| detection of genetic diversity among bovine immunodeficiency virus population by single-strand conformation polymorphism analysis. | serial virus specimens rescued from rabbits, experimentally infected with bovine immunodeficiency (biv) strain r29, were monitored for changes in quasispecies population, using the single-strand conformation polymorphism (sscp) analysis. the generation of characteristic sscp patterns enables the rapid differentiation of biv variants derived from the conserved part on the env region of the biv genome, reducing the need for expensive and time-consuming direct sequencing analyses. our results showe ... | 2000 | 11016600 |
| malignant catarrhal fever: polymerase chain reaction survey for ovine herpesvirus 2 and other persistent herpesvirus and retrovirus infections of dairy cattle and bison. | using a polymerase chain reaction (pcr) test for sequences of ovine herpesvirus 2 (ohv2), this virus was shown to be significantly associated with sheep-associated malignant catarrhal fever (sa-mcf) in terminal cases of disease in 34 cattle and 53 bison. ovine herpesvirus 2 was not detected in cattle (38) and bison (10) that succumbed to other diseases. other persistent herpesviruses, retroviruses, and pestivirus, some of which have been previously isolated from cases of sa-mcf, were not associa ... | 2000 | 11021426 |
| an rna-binding chameleon. | the arginine-rich rna binding motif is found in a wide variety of proteins, including several viral regulatory proteins. although related at the primary sequence level, arginine-rich domains from different proteins adopt different conformations depending on the rna site recognized, and in some cases fold only in the context of rna. here we show that the rna binding domain of the jembrana disease virus (jdv) tat protein is able to recognize two different tar rna sites, from human and bovine immun ... | 2000 | 11106746 |
| binding of a cyclic biv beta-tat peptide with its tar rna construct. | the ability of rna structures to adopt diverse yet complex tertiary structures has resulted in numerous fascinating rna-protein recognition events. it was recently reported that a close relative of the hiv rev peptide, namely a 17 residue tat peptide from bovine immuno-deficiency virus (biv), is able to bind to the 28 nucleotide biv tar rna construct. here we report that by simply converting the 17 residue beta-ribbon peptide structure to a 19 residue cyclopeptide, the binding affinity (kd) of t ... | 2001 | 11140729 |
| overexpression and purification of an immunologically reactive his-biv capsid fusion protein. | the gene of the capsid protein of bovine immunodeficiency virus (biv) was linked to a sequence encoding for six histidines and expressed as the (his)6 p26 capsid fusion protein. the fusion protein was strongly expressed as both soluble and insoluble forms after induction by isopropylthio-beta-d-galactoside. purification was based on interaction of the hexa-histidine polypeptide with metal ions. expression could represent 11% of the total protein in escherichia coli, allowing more than 20 mg of h ... | 1999 | 10092485 |
| detection of bovine retrospumavirus by the polymerase chain reaction. | a polymerase chain reaction (pcr) assay was developed for detection of bovine retrospumavirus (bovine syncytial virus; bsv) provirus dna. two different sets of oligonucleotide primers complementary to sequences located in the gag and the pol/env gene regions were used and compared for their ability to amplify the targeted bsv sequences by pcr. the results obtained from this study have shown that it is possible to amplify the bsv provirus dna sequences not only from total dna of bsv-infected cell ... | 1999 | 10204710 |
| experimental collection and transfer of embryos from bovine immunodeficiency virus (biv) infected cattle. | three experiments were conducted to determine whether the lentivirus, bovine immunodeficiency virus (biv) is likely to be transmitted via embryo transfer. in the first experiment, embryos collected from biv-negative heifers were exposed in vitro to biv for 24 h, washed and then tested for the presence of the provirus. in the second experiment, embryos obtained from biv-negative heifers were transferred to the uterine horns of biv-infected heifers; 24 h later these embryos were recovered and test ... | 2001 | 11233789 |
| differentiation of two bovine lentiviruses by a monoclonal antibody on the basis of epitope specificity. | bovine immunodeficiency virus (biv) and jembrana disease virus (jdv) are bovine lentiviruses that are closely related genetically. a recombinant fusion protein containing the capsid protein of biv expressed in escherichia coli was used to immunize mice and produce monoclonal antibodies. six hybridomas specific for biv capsid protein were identified, and one antibody, designated 10h1, was characterized further. competitive binding assays were performed to analyze the topography of antigenic deter ... | 2001 | 11238209 |
| construction and molecular analysis of gene transfer systems derived from bovine immunodeficiency virus. | because lentiviruses are able to infect nondividing cells, these viruses might be utilized in gene therapy applications where the target cell does not divide. however, it has been suggested that the introduction of primate lentivirus sequences, particularly those of human immunodeficiency virus, into human cells may pose a health risk for the patient. to avoid this concern, we have constructed gene transfer systems based on a nonprimate lentivirus, bovine immunodeficiency virus. a panel of vecto ... | 2001 | 11238863 |
| an atypical lymphoma of t-cell lineage in the thorax of an aged cow. | an aged beef cow was presented for signs of thoracic disease. a complete clinical and diagnostic workup suggested neoplasia. postmortem examination revealed a lymphoma of t-cell lineage confined solely to the thoracic cavity, predominantly in lung tissue. the diagnosis was based on light and electron microscopy, immunohistochemistry, and negative bovine leukemia virus and bovine immunodeficiency virus results. | 2001 | 11289212 |
| evidence for the presence of two bovine lentiviruses in the cattle population of bali. | antibodies directed against two bovine lentiviruses, jembrana disease virus (jdv) and bovine immunodeficiency virus (biv), were detected in balinese cattle sera using two new enzyme-linked immunosorbent assays (elisas) based on the combination of capsid (ca) protein and transmembrane (tm) peptides derived from jdv or biv sequences. twenty eight of the 77 sera tested on the jdv elisa showed anti-jdv antibodies with an unequal distribution of seropositive animals throughout the different districts ... | 2001 | 11348768 |
| [construction and analysis of activity of an hiv-1/bovine immunodeficiency virus chimeric clone cdna]. | chimeric human/bovine immunodeficiency virus (hbiv) cdna was constructed by replacing hiv tat and ltr with bovine immunodeficiency virus (biv) tat and ltr to study the activity of biv tat and ltr in the chimerae. | 2003 | 12869996 |
| molecular dynamics and binding specificity analysis of the bovine immunodeficiency virus biv tat-tar complex. | we have performed molecular dynamics (md) simulations, with particle-mesh ewald, explicit waters, and counterions, and binding specificity analyses using combined molecular mechanics and continuum solvent (mm-pbsa) on the bovine immunodeficiency virus (biv) tat peptide-tar rna complex. the solution structure for the complex was solved independently by patel and co-workers and puglisi and co-workers. we investigated the differences in both structures and trajectories, particularly in the formatio ... | 2001 | 11371457 |
| phylogenetic relationships of bovine immunodeficiency virus in cattle and buffaloes based on surface envelope gene sequences. brief report. | isolates of bovine immunodeficiency virus (biv) exhibit a striking genomic diversity, most of which are located in the viral envelope gene. since this property of the biv group of viruses may play an important role in the pathobiology of the virus, the surface envelope gene, particularly the conserved (c) 2, hypervariable (v) 1, v2 and c3 regions, of eleven different isolates from different environments with different bovine breeds naturally infected with biv, including dairy cows in japan, buff ... | 2001 | 11448023 |
| in vivo transcription of bovine leukemia virus and bovine immunodeficiency-like virus. | cellular tropism and transcription of bovine leukemia virus (blv) and bovine immunodeficiency-like virus (biv) were investigated using peripheral blood mononuclear cells (pbmc) collected from a cow infected with both viruses. each pbmc subset, purified by magnetic cell sorting, was subjected to pcr and rt-pcr for detection of their integrated proviruses and transcript mrnas. both blv and biv genomes were detected by nested pcr in cd3(+), cd4(+), cd8(+) and gammadelta t cells, b cells and monocyt ... | 2003 | 14602199 |
| prevalence of bovine immunodeficiency virus infection in cattle in great britain. | | 2001 | 11688750 |
| cis-acting sequences may contribute to size variation in the surface glycoprotein of bovine immunodeficiency virus. | genetic recombination is an important mechanism of retrovirus variation and diversity. size variation in the surface (su) glycoprotein, characterized by duplication and insertion, has been observed during in vivo infection with several lentiviruses, including bovine immunodeficiency virus (biv), equine infectious anaemia virus (eiav) and human immunodeficiency virus type 1. these duplication/insertion events are thought to occur through a mechanism of template switching/strand transfer during re ... | 2001 | 11714975 |
| vertical transmission of bovine leukemia virus and bovine immunodeficiency virus in dairy cattle herds. | vertical transmission of bovine leukemia virus (blv) and bovine immunodeficiency virus (biv) was investigated in five dairy cattle herds in hokkaido, where 36.1 and 17.0% of cattle were blv and biv seropositive, respectively, and 9.9% of dams were co-infected with both biv and blv. twenty six cases of offspring born from dams infected with only blv (17 cases) or with both biv and blv (9 cases) were examined for the presence of blv and biv before and after colostrum feeding by polymerase chain re ... | 2002 | 11731179 |
| envelope glycoprotein cytoplasmic domains from diverse lentiviruses interact with the prenylated rab acceptor. | lentivirus envelope glycoproteins have unusually long cytoplasmic domains compared to those of other retroviruses. to identify cellular binding partners of the simian immunodeficiency virus (siv) envelope transmembrane protein (gp41) cytoplasmic domain (cd), we performed a yeast two-hybrid screen of a phytohemagglutinin-activated human t-cell cdna library with the siv gp41 cd. the majority of positive clones (50 of 54) encoded the prenylated rab acceptor (pra1). pra1 is a 21-kda protein associat ... | 2002 | 11739697 |
| construction and characterization of a chimeric virus (biv/hiv-1) carrying the bovine immunodeficiency virus gag-pol gene. | hiv-1(hxb2) 5'ltr region, most of biv(r29) gag-pol segment and hiv-1(hxb2) pol in-3'ltr region were respectively amplified. a chimeric clone, designated as phbiv(3753), was constructed by cloning three fragments sequentially into puc18. mt4 cells were transfected with phbiv3753. the replication and expressions of the chimeric virus (hbiv3753) were monitored by rt activity and ifa. the results firstly demonstrated that it is possible to generate a new type of the biv/hiv-1 chimeric virus containi ... | 2002 | 11741171 |
| confirmation of vertical transmission of bovine immunodeficiency virus in naturally infected dairy cattle using the polymerase chain reaction. | the purpose of this study was to determine whether bovine immunodeficiency virus (biv) is vertically transmitted in naturally infected dairy cattle. twenty-two dam/calf pairs from a mississippi agriculture and forestry experiment station dairy were the study group. blood samples were collected following delivery of calves, the peripheral blood leukocytes were purified from these samples, and the leukocyte dna was used in polymerase chain reactions targeting the pol gene region of the biv proviru ... | 2002 | 11939331 |
| tat protein expression in mdbk cells does not confer susceptibility to bovine immunodeficiency virus. | the ability of biv strain r29 to infect bovine cell lines in the presence or absence of a functional lentiviral tat protein is described. jembrana disease virus (jdv) tat protein was stably expressed in mdbk cells. no viral replication could be detected in this cell line after infection with biv r29. transfection of mdbk cells and mdbk tat expressing cells with biv r29 proviral dna established that biv r29 could not replicate in mdbk cells. whether viral entry into mdbk cells is also a block to ... | 2002 | 11958463 |
| a synthetic rev-independent bovine immunodeficiency virus-based packaging construct. | replication competent lentivirus (rcl) has been the major safety concern associated with applications of lentivirus-based gene transfer systems for human gene therapy. minimization and elimination of overlaps between the packaging and the transfer vector constructs are expected to reduce the potential to generate rcl. we previously developed second- and third-generation bovine immunodeficiency virus (biv)-based gene transfer systems. however, some sequence homologies between the vector and gag/p ... | 2004 | 15353041 |
| bovine immunodeficiency virus expression in vitro is reduced in the presence of beta-chemokines, mip-1alpha, mip-1beta and rantes. | the inhibition of hiv expression in vitro by a cocktail of the beta-chemokines mip-1alpha, mip-1beta and rantes provided the initial evidence that hiv utilizes chemokine receptors as co-receptors for infection of cells. bovine immunodeficiency virus (biv), a lentivirus, infects a wide variety of leukocyte populations, but the cellular receptor(s) utilized by this virus for infection of cells is not known. the purpose of this study was to determine whether mip-1alpha, mip-1beta and rantes affect ... | 2002 | 12090295 |
| bovine leukemia virus su protein interacts with zinc, and mutations within two interacting regions differently affect viral fusion and infectivity in vivo. | bovine leukemia virus (blv) and human t-cell lymphotropic virus type 1 (htlv-1) belong to the genus of deltaretroviruses. their entry into the host cell is supposed to be mediated by interactions of the extracellular (su) envelope glycoproteins with cellular receptors. to gain insight into the mechanisms governing this process, we investigated the ability of su proteins to interact with specific ligands. in particular, by affinity chromatography, we have shown that blv su protein specifically in ... | 2002 | 12134000 |
| development of second- and third-generation bovine immunodeficiency virus-based gene transfer systems. | lentivirus-based gene transfer systems have demonstrated their utility in mediating gene transfer to dividing and nondividing cells both in vitro and in vivo. an early-generation gene transfer system developed from bovine immunodeficiency virus (biv) has been described (berkowitz et al., j. virol. 2001;75:3371-3382). in this paper, we describe the development of second-generation (three-plasmid) and third-generation (four-plasmid) biv-based systems. all accessory genes (vif, vpw, vpy, and tmx) a ... | 2002 | 12162812 |
| sustained transduction of ocular cells with a bovine immunodeficiency viral vector. | human immunodeficiency viral (hiv) vectors mediate long-term transduction of many types of nondividing cells in vivo. bovine immunodeficiency virus (biv) is a lentivirus that shares many characteristics with hiv, but does not cause human disease. in this study, we investigated the potential of biv vectors for ocular gene therapy. an enhanced green fluorescent protein (egfp)-encoding reporter gene was packaged in recombinant biv vector (biv.egfp). adult c57bl/6 mice were given an intravitreous (5 ... | 2002 | 12162813 |
| seroprevalence and molecular evidence for the presence of bovine immunodeficiency virus in brazilian cattle. | data on the worldwide distribution of bovine immunodeficiency virus (biv) and bovine leukemia virus (blv) is limited. a prevalence study of antibodies to biv and blv was conducted in six different cattle herds in brazil. out of a total of 238 sera analyzed, 11.7% were found positive for anti-biv p26 antibodies as determined by western blot analysis, 2.1% were positive for anti-blv gp51 antibodies as detected by immunodiffusion test. peripheral blood mononuclear cells from biv seropositive cattle ... | 2002 | 12201018 |
| illegal aids vaccine causes concern in india. | sylka, a florida-based company, financed the illegal clinical trial of bovine immunodeficiency vaccine (biv) in human subjects. in march 1994, 10 people infected with hiv in mumbai, india, were administered their first dose of biv. a booster dose was given 1 month later. before the third round, however, the trial was abruptly abandoned. one patient has since died, one patient is dying of leukemia, and two of the remaining eight could not be traced. this experiment was not approved by the dr ... | 1996 | 12320587 |
| structure-based design of a dimeric rna-peptide complex. | the arginine-rich rna-binding domain of bovine immunodeficiency virus (biv) tat adopts a beta-hairpin conformation upon binding to the major groove of biv tar. based on its nmr structure, we modeled dimeric arrangements in which two adjacent tar sites might be recognized with high affinity by a dimeric peptide. some dimeric rnas efficiently bound two unlinked biv tat peptides in vitro, but could not bind even one monomeric peptide in vivo, as monitored by transcriptional activation of human immu ... | 2001 | 11226168 |
| very low prevalence of bovine immunodeficiency virus infection in western canadian cattle. | bovine immunodeficiency virus (biv) is a lentivirus that causes disease in cattle. despite the large cattle industry in western canada, the presence of biv has not been examined to date. genomic dna, derived from semen and buffy coat samples, was analyzed by nested polymerase chain reaction (pcr) using specific primers for the gag, pol, and env genes of biv. despite utilizing a procedure that detected a minimum of 10 proviral copies, biv sequences were not amplified in any of 317 buffy coat and ... | 2001 | 11227201 |
| natural bovine lentiviral type 1 infection in holstein dairy cattle. i. clinical, serological, and pathological observations. | clinical, serological, and pathological abnormalities observed in holstein cows naturally infected with bovine lentivirus 1 bovine immunodeficiency virus (biv) and other infections were progressive and most commonly associated with weight loss, lymphoid system deficiency, and behavioral changes. clinical evidence of meningoencephalitis was dullness, stupor, and occasional head or nose pressing postures. the polymerase chain reactions associated the biv provirus with the lesions in the central ne ... | 2003 | 12493490 |
| replication of human immunodeficiency viruses engineered with heterologous tat-transactivation response element interactions. | human immunodeficiency viruses (hivs) and the related bovine lentiviruses bovine immunodeficiency virus (biv) and jembrana disease virus (jdv) utilize the viral tat protein to activate viral transcription. the arginine-rich rna-binding domains of the tat proteins bind to their cognate transactivation response element (tar) rna hairpins located at the 5' ends of the viral mrnas, resulting in enhanced processivity of rna polymerase ii. it has previously been shown that hiv type 1 (hiv-1) tat requi ... | 2003 | 12525632 |
| natural bovine lentivirus type 1 infection in holstein dairy cattle. ii. lymphoid tissue lesions. | bovine immunodeficiency virus (biv) in holstein cows was associated with morphologic evidence of lymphoid organ deficiency. cows were subjected to normal management practices including parturition and lactation without adverse environmental stresses. during the clinical disease process there was marked weight loss and wasting with frequent and severe concurrent infections. lymphoid follicular hyperplasia and dysplasia in lymph nodes, and hypertrophy and hyperplasia in hemal lymph nodes were char ... | 2003 | 12602682 |
| the catalytic properties of the recombinant reverse transcriptase of bovine immunodeficiency virus. | bovine immunodeficiency virus (biv) is a lentivirus with no proven pathogenesis in infected cattle. yet, in experimentally infected rabbits, it causes an aids-like disease. consequently, we expressed two recombinant isoforms of biv reverse transcriptase (rt), which differ in their c-termini, and studied their catalytic properties. both isoforms prefer mg(+2) over mn(+2) with most dna polymerase and ribonuclease-h substrates. the processivity of dna synthesis by the biv rts is higher than that of ... | 2006 | 16631225 |
| from mice to macaques--animal models of hiv nervous system disease. | lentiviral diseases of animals have been recognized for over a century, long before hiv was recognized as the cause of aids. all lentiviruses cause neurological disease and productive virus replication in the cns occurs exclusively in cells of macrophage lineage. the ability to molecularly engineer the inoculum virus, to sample the brain at many different time points from acute through terminal infection and to correlate in vivo with in vitro findings are significant advantages of animal models ... | 2006 | 16842082 |
| seroprevalence of bovine immunodeficiency virus and bovine leukemia virus in dairy and beef cattle in hokkaido. | serological survey of bovine immunodeficiency virus (biv) and bovine leukemia virus (blv) infection was conducted in dairy cattle from 10 different regions of hokkaido, japan. among 390 cattle, 11.0% of cattle were biv-seropositive and 3.3% were blv-seropositive. moreover, in two dairy farms, where bovine leukosis has been reported, prevalence of biv infections were 6.4 and 9.1%, respectively. in contrast, among 150 beef cattle, 16.6% were biv-seropositive while none was blv-seropositive. dual i ... | 2003 | 12655131 |
| evidence of bovine immunodeficiency virus in cattle in turkey. | a seroepidemiological study of bovine immunodeficiency virus (biv) and bovine leukemia virus (blv) infections was conducted in four different cattle herds in turkey. a total of 300 blood samples were analyzed and 12.3% were found to be positive for anti-biv p26 antibodies by western blot analysis and 1.6% positive for anti-blv gp51 antibodies by an immunodiffusion test. biv infection was confirmed with the detection of biv-provirus dna using the nested polymerase chain reaction. this is the firs ... | 2003 | 12921344 |
| estimation of sensitivity and specificity of two diagnostics tests for bovine immunodeficiency virus using bayesian techniques. | the validation of assays for bovine immunodeficiency virus (biv) in cattle is hampered by the absence of a gold standard. two tests that often are used to detect biv are the indirect fluorescent-antibody assay (ifa) and the nested-set polymerase chain-reaction assay (pcr). ifa detects an antibody response whereas pcr detects the provirus in white blood cells. using bayesian techniques performed simultaneously on animals from two different dairy herds, we estimated the performance of the ifa and ... | 2003 | 14519338 |
| design of a cyclic peptide that targets a viral rna. | the tat protein controls transcription in lentiviruses such as hiv. a cyclic peptide analog of the rna binding domain of the bovine immunodeficiency virus (biv) tat protein is shown to bind specifically to its target rna stem loop. nmr data indicate a similar mode of binding of linear and cyclic peptides. | 2003 | 14677935 |
| important role for the ca-nc spacer region in the assembly of bovine immunodeficiency virus gag protein. | lentiviral gag proteins contain a short spacer sequence that separates the capsid (ca) from the downstream nucleocapsid (nc) domain. this short spacer has been shown to play an important role in the assembly of human immunodeficiency virus type 1 (hiv-1). we have now extended this finding to the ca-nc spacer motif within the gag protein of bovine immunodeficiency virus (biv). mutation of this latter spacer sequence led to dramatic reductions in virus production, which was mainly attributed to th ... | 2004 | 14694086 |
| sensitive and specific detection of bovine immunodeficiency virus and bovine syncytial virus by 5' taq nuclease assays with fluorescent 3' minor groove binder-dna probes. | sensitive assays are required to detect bovine retroviruses in donor cattle used for the in vivo preparation of australian tick fever vaccines. 5' taq nuclease assays using 3' minor groove binder dna probes (taqman)mgb) were developed and compared to conventional pcr assays for the sensitive detection of bovine syncytial virus (bsv) and bovine immunodeficiency virus (biv). seven beef and dairy herds were screened to evaluate these tests. comparative sensitivities of pcr tests were determined by ... | 2004 | 14715301 |
| selection of tar rna-binding chameleon peptides by using a retroviral replication system. | the interaction between the arginine-rich motif (arm) of the human immunodeficiency virus (hiv) tat protein and tar rna is essential for tat activation and viral replication. two related lentiviruses, bovine immunodeficiency virus (biv) and jembrana disease virus (jdv), also require tat arm-tar interactions to mediate activation, but the viruses have evolved different rna-binding strategies. interestingly, the jdv arm can act as a "chameleon," adopting both the hiv and biv tar binding modes. to ... | 2004 | 14722301 |
| evidence for conformational flexibility in the tat-tar recognition motif of cyclin t1. | cyclin t1 (cyct1) is a cellular transcription elongation factor that also participates in tat-mediated activation of several lentiviral promoters. in human immunodeficiency virus (hiv), cyct1 is required for tat to bind tightly to tar and interacts in the ternary complex via its tat-tar recognition motif (trm). in the related bovine immunodeficiency virus (biv), tat recognizes its cognate tar element with high affinity and specificity in the absence of cyct1. at both promoters, cyct1 recruits th ... | 2004 | 14972556 |
| molecular basis of the internalization of bovine immunodeficiency virus tat protein. | bovine immunodeficiency virus (biv) is a nonacute, pathogenic, and horizontally transmitted lentivirus. it shares the parallel properties in morphology and genetics with human immunodeficiency virus type 1 and other lentiviruses. biv encodes its own transactivator (btat), which transactivates its cognate long terminal repeat (ltr). however, the mechanism involved in the transactivation is different from that in hiv and other lentiviruses. we determined the mechanisms of btat internalization by c ... | 2008 | 17952584 |
| structural mimicry of retroviral tat proteins by constrained beta-hairpin peptidomimetics: ligands with high affinity and selectivity for viral tar rna regulatory elements. | an approach is described to the design of beta-hairpin peptidomimetic ligands for bovine immunodeficiency virus (biv) tat protein, which inhibit binding to its transactivator response element (tar) rna. a library of peptidomimetics was derived by grafting onto a hairpin-inducing d-pro-l-pro template sequences related to the rna recognition element in tat. one hairpin mimetic was identified that binds tightly (k(d) approximately 150 nm) to biv tar, and another that binds also to hiv-1 tar rna (k( ... | 2004 | 15174860 |
| evidence for bovine immunodeficiency virus infection in cattle in zambia. | we report herein on the first evidence for the presence of bovine immunodeficiency virus (biv) in zambia. serological surveillance of biv and bovine leukemia virus (blv) was conducted in traditional cattle herds in zambia. out of a total of 262 sera analyzed, 11.4% were found positive for anti-biv p26 antibodies as determined by western blot analysis, while 5.0% were positive for anti-blv gp51 antibodies as detected by immunodiffusion test. peripheral blood mononuclear cells from biv seropositiv ... | 2004 | 15253302 |
| a comparative binding study of modified bovine immunodeficiency virus tar rna against its tat peptide. | besides generating novel binding peptides or small molecules to their rna target, successful design of chemically modified rna constructs capable of tighter binding with their binding peptides is also of significant importance. herein, the synthesis and binding studies of a series of both wt and mutant bovine immunodeficiency virus (biv) tar rna constructs against its tat peptide are reported. understanding the requirements that enable rna construct binding properties, especially at the hairpin ... | 2004 | 15546738 |
| a comparative binding study of biv tat peptide against its tar rna duplex, rna-dna heteroduplex and dna duplex. | association between rna and dna strands to form rna-dna heteroduplex is important in many biological processes such as transcription, dna replication and reverse transcription. herein, binding affinities of a 17-mer biv tat peptide is compared with tar dna duplex, tar rna-dna heteroduplex and tar rna duplex. it was observed that binding affinities of tat peptide is comparable against dna-rna heteroduplex and rna duplex, whereas dna duplex binding is decidedly poor. | 2005 | 15582425 |
| prevalence of antibodies to bovine respiratory viruses in cattle infected with bovine immunodeficiency virus. | | 2008 | 18487588 |
| recombinant jembrana disease virus gag proteins identify several different antigenic domains but do not facilitate serological differentiation of jdv and nonpathogenic bovine lentiviruses. | in indonesia, it is suspected that there are two bovine lentiviruses circulating in the cattle population: a pathogenic jembrana disease virus (jdv), and a nonpathogenic bovine immunodeficiency-like virus (biv). both viruses cross-react antigenically and cannot be differentiated by current serological tests using jdv antigens. to identify possible type-specific epitopes, a series of recombinant protein constructs including the matrix, capsid and nucleocapsid proteins were produced from jdv gag a ... | 2004 | 15664061 |
| characterization of biv env core: implication for mechanism of biv-mediated cell fusion. | entry of lentiviruses, such as human immunodeficiency virus type 1 (hiv-1) and simian immunodeficiency virus (siv), requires folding of two heptad repeat regions (hr1 and hr2) of gp41 into a trimer-of-hairpins, which subsequently brings virus and cell membrane into fusion. this motif is a generalized feature of viral fusion proteins and has been exploited in generating antiviral fusion agents. in the present paper, we report structural characters of env protein from another lentivirus, bovine im ... | 2005 | 15737628 |