| productive infection of primary cultures of endothelial cells from the cat liver sinusoid with the feline immunodeficiency virus. | given the similarities between the two viruses, the feline immunodeficiency virus (fiv) is becoming an interesting animal model for human immunodeficiency virus (hiv) studies. to explore the still controversial role of the liver in the development of hiv infection, sinusoidal endothelial cells (sec) were isolated, and primary cultures were infected with the fiv villefranche iffa strain. the isolated cells were characterized by their typical fenestrations, the presence of von willebrand factor (v ... | 1996 | 8621176 |
| the mutation frequency of feline immunodeficiency virus enhanced by 3'-azido-3'-deoxythymidine. | we have developed a host range system to measure the mutation frequency of feline immunodeficiency virus (fiv), the feline homologue of human immunodeficiency virus type 1 (hiv-1). when wild-type fiv was grown in the presence of a known mutagen, 5-bromo-2'-deoxyuridine (budr), a dose-dependent increase of host range mutants was detected. using this system, we have evaluated the effects of antiviral drugs upon the mutation frequency of fiv. subinhibitory concentrations of 3'-azido-3'-deoxythymidi ... | 1996 | 8624757 |
| neutralization sensitivity and accessibility of continuous b cell epitopes of the feline immunodeficiency virus envelope. | antibodies elicited during natural infection of domestic cats by the feline immunodeficiency virus (fiv) recognize continuous epitopes in nine domains of the virus envelope glycoproteins. whereas antibodies directed against the v3 envelope region can neutralize laboratory-adapted virus, neutralization of fiv has been shown to depend upon cellular substrate, and virus adaptation to laboratory cell lines may alter sensitivity to neutralizing antibodies. we therefore undertook a systematic analysis ... | 1996 | 8627265 |
| frequent perinatal transmission of feline immunodeficiency virus by chronically infected cats. | vertical transmission of feline immunodeficiency virus (fiv) was studied in cats infected with either of two fiv clinical isolates (fiv-b-2542 or fiv-ab-2771) prior to breeding and conception. queens infected 4 to 30 months (mean = 14 months) prior to conception transmitted fiv to 59 of 83 (71%) kittens; 50.6% were virus positive on the day of birth. to examine potential routes of fiv transmission from mother to offspring, kittens were delivered via either vaginal or cesarean birth and nursed by ... | 1996 | 8627764 |
| molecularly cloned feline immunodeficiency virus ncsu1 jsy3 induces immunodeficiency in specific-pathogen-free cats. | a full-length feline immunodeficiency virus ncsu1 (fiv-ncsu1) genome (jsy3) was cloned directly from fiv-ncsu1-infected feline cd4+ lymphocyte (fcd4e) genomic dna and identified by pcr amplification with 5' long terminal repeat, gag, env, and 3' long terminal repeat primer sets. supernatant from fcd4e cells cocultured with jsy3-transfected crandell feline kidney (crfk) cells was used as an inoculum. cell-free jsy3 virus was cytopathogenic for fcd4e lymphocytes but did not infect crfk cells in vi ... | 1996 | 8627777 |
| synthesis and targeted delivery of an azidothymidine homodinucleotide conferring protection to macrophages against retroviral infection. | the infectivity and replication of human (hiv-1), feline (fiv), and murine (lp-bm5) immunodeficiency viruses are all inhibited by several nucleoside analogues after intracellular conversion to their triphosphorylated derivatives. at the cellular level, the main problems in the use of these drugs concern their limited phosphorylation in some cells (e.g., macrophages) and the cytotoxic side effects of nucleoside analogue triphosphates. to overcome these limitations a new nucleoside analogue homodi ... | 1996 | 8633079 |
| allogeneic marrow transplantation in a cat with acute myeloid leukemia. | a listless, anorectic 2-year-old cat was found to have a normocytic, nonregenerative anemia. a diagnosis of acute myeloid leukemia type m6er was made. because the cat was young, had negative felv and feline immunodeficiency virus test results, had a sibling that could be used as a bone marrow donor, had received only 1 transfusion, and was in good health other than being anemic, allogeneic bone marrow transplantation (bmt) was attempted using marrow from the cat's sibling. the most life-threaten ... | 1996 | 8635972 |
| inhibitory rna ligand to reverse transcriptase from feline immunodeficiency virus. | high-affinity, high-specificity rna ligands for reverse transcriptase from feline immunodeficiency virus (fiv) were isolated from an rna library by the selex (systematic evolution of ligands by exponential enrichment) procedure. the selected rna ligands bound to fiv reverse transcriptase with dissociation constants in the nanomolar range. one of the ligands was a potent inhibitor of the rna-dependent dna polymerase activity of both the recombinant and the virion-derived fiv reverse transcriptase ... | 1996 | 8639644 |
| evidence for cd8+ antiviral activity in cats infected with feline immunodeficiency virus. | human immunodeficiency virus (hiv) causes a long, asymptomatic infection characterized by normal to elevated numbers of circulating cd8+ cells and a progressive decline in cd4+ cells. it has been speculated that hiv-specific antiviral activity driven by cd8+ t cells may control viral replication during this period and maintain the clinically asymptomatic stage of disease. the disease induced in cats by feline immunodeficiency virus (fiv) is similar to hiv in that it is characterized by a long as ... | 1996 | 8642675 |
| plasma viral rna load predicts disease progression in accelerated feline immunodeficiency virus infection. | viral rna load has been shown to indicate disease stage and predict the rapidity of disease progression in human immunodeficiency virus type 1 (hiv-1)-infected individuals. we had previously demonstrated that feline immunodeficiency virus (fiv) rna levels in plasma correlate with disease stage in infected cats. here we expand upon those observations by demonstrating that plasma virus load is 1 to 2 logs higher in cats with rapidly progressive fiv disease than in long-term survivors. differences ... | 1996 | 8642679 |
| [vaccination against feline retrovirus infections]. | feline leukemia virus (felv) and feline immunodeficiency virus (fiv), both of veterinary importance, their antigenic and genetic variability as well as their pathogenicity are described. disease following felv infection is interpreted as a consequence of genetic recombination, as a result of viral evolution in vivo. the principles and efficacy of vaccines are discussed. | 1996 | 8650690 |
| inhibition of feline immunodeficiency virus infection in vitro by envelope glycoprotein synthetic peptides. | sixty-six 20- to 23-amino-acid synthetic peptides, partially overlapping by 10-12 amino acids, spanning the entire sequence of the envelope su and tm glycoproteins of the petaluma isolate of fiv, have been used to investigate the env domains involved in viral infection. peptides 5 to 7, spanning amino acids 225e-p264 located in a conserved region of the su protein, and peptides 58 to 61, spanning amino acids 767n-p806 and encompassing hypervariable region 8 of tm protein, exhibited a remarkable ... | 1996 | 8661378 |
| a longitudinal study of feline immunodeficiency virus-specific cytotoxic t lymphocytes in experimentally infected cats, using antigen-specific induction. | the evolution of the virus-specific cytotoxic t-lymphocyte response in two cats experimentally infected with feline immunodeficiency virus (fiv) was monitored. effector cells were derived from peripheral blood lymphocytes during the acute and chronic phases of infection (0 to 21 and 62 to 127 weeks, respectively) and from the spleen and lymph nodes at 127 weeks after infection. lymphocytes were restimulated in vitro with paraformaldehyde-fixed, autologous lymphoblasts which had been infected wit ... | 1996 | 8709246 |
| the feline herpesvirus type 1 icp4 down-regulates feline immunodeficiency virus long terminal repeat (ltr)-directed gene expression via the c/ebp site in the ltr. | we investigated effects of feline herpesvirus type 1 (fhv-1) icp4 on feline immunodeficiency virus (fiv) long terminal repeat (ltr)-directed gene expression by transient transfection assay in crandell feline kidney cells. we demonstrated that fhv-1 icp4 significantly stimulates the fiv ltr after introduction of site-specific mutation of the c/ebp site in the ltr, and the c/ebp site is sufficient to confer inhibitory effects by fhv-1 icp4 on a heterologous promoter. these results indicate that fh ... | 1995 | 8720064 |
| [quantification of proviral fiv dna using competitive pcr]. | quantification of provirus copies is important in the context of different biological questions. the most reliable approach for dna quantification is a pcr based on coamplification of two templates of similar length, the target sequence and the reference template, sharing the same primer recognition sequences. during the amplification, the two templates compete for the same primer set (competitive pcr, or cpcr) and consequently amplify at the same rate independently of the number of cycles. the ... | 1996 | 8720733 |
| suppression of virus burden by immunization with feline immunodeficiency virus env protein. | whole inactivated virus (wiv) vaccines derived from the fla cell line protect cats against challenge with feline immunodeficiency virus (fiv). to discover whether the protective effects of wiv could be reproduced by the isolated env component, either wiv or immunoaffinity-purified fiv gp120 from the fl4 cell line was administered to cats. although both vaccines induced high levels of virus neutralizing antibodies, purified env was much less effective than wiv in protecting cats against viraemia. ... | 1996 | 8735552 |
| regulatory properties of the integrated long terminal repeat of the feline immunodeficiency virus. | to examine the regulatory properties of feline immunodeficiency virus (fiv) long terminal repeat (ltr) integrated into host chromatin, crandell feline kidney cells were stably transfected with the fiv ltr that directs the bacterial chloramphenicol acetyltransferase (cat) gene. using these cells, we examined the effects of treatment with several chemical agents, infection with feline viruses, or transfection with effector plasmids expressing fiv gene products on fiv ltr-directed gene expression. ... | 1996 | 8738180 |
| histologic classification and immunophenotype of lymphosarcomas in cats with naturally and experimentally acquired feline immunodeficiency virus infections. | lymphosarcoma (malignant lymphoma) is the commonest hematopoietic tumor in the cat. many cases are associated with feline leukemia virus (felv) infection, but epidemiologic and experimental data suggest that feline immunodeficiency virus (fiv) may also have a role in lymphomagenesis. in this paper, we describe the clinical presentation, histologic classification, and immunophenotype of lymphosarcoma in eight domestic cats with natural or experimental fiv infections. the tumors were often of unus ... | 1996 | 8740699 |
| evaluation of subunit vaccines against feline immunodeficiency virus infection. | subunit vaccines prepared against feline immunodeficiency virus (fiv) infection were evaluated in two trials. first, cats were immunized with bacterial expression products of an envelope fragment that contained the v3 neutralization domain of the fiv surface protein fused to either galactokinase (k-su3) or glutathione-s-transferase (g-su3). quantitative and qualitative differences in the humoral immune response were observed with three adjuvants of which quil a was the best in terms of total and ... | 1996 | 8744554 |
| coadaptation and immunodeficiency virus: lessons from the felidae. | the emergence of pathogenic viruses in new species offers an unusual opportunity to monitor the coadaptation of viruses and their hosts in a dynamic ongoing process of intense biological selection. tracking lentivirus epidemics in man, monkeys and cats reveals genomic struggles at three levels: quasispecies divergence within an individual; coadaptation of virus and host genomes subsequent to disease outbreaks; and transmission, spread and pathogenesis in related host species. aspects of each lev ... | 1995 | 8745072 |
| development of a simple, rapid and accurate in vitro whole blood technique for the detection and semi-quantification of fiv cellular viremia. | a new, simple, rapid and accurate culture technique is described for a semi-quantitative analysis of cellular viremia in fiv-infected cats. this assay can be carried out with small amounts of whole blood, and is based on the detection of fiv core gag antigen, which is released in culture supernatants. the amount of core antigen produced is measured with an enzyme-linked immunoassay using specific monoclonal antibodies. this whole blood technique (wb method) was compared with a culture method usi ... | 1995 | 8748548 |
| a characteristic bent conformation of rna pseudoknots promotes -1 frameshifting during translation of retroviral rna. | the structures of four different rna pseudoknots that provide one of the signals required for ribosomal frameshifting in mouse mammary tumor virus have been determined by nmr. the rna pseudoknots have similar sequences and assume similar secondary structures, but show significantly different frameshifting efficiencies. the three-dimensional structures of one frameshifting and one non-frameshifting rna pseudoknot had been determined previously by our group. here we determine the structures of two ... | 1996 | 8759314 |
| molecular biology of the feline immunodeficiency virus auxiliary genes. | | 1996 | 8760407 |
| feline immunodeficiency virus can infect a human cell line (molt-4) but establishes a state of latency in the cells. | infectivity of feline immunodeficiency virus (fiv) in feline and human lymphoblastoid cell lines was examined using homogeneous populations of fiv derived from infectious molecular clones of strains tmz and petaluma, and two recombinant chimeric clones carrying gag, pol, vif and orf-a from the heterologous virus. fiv from the clones with the env region of the petaluma strain was shown to infect and establish provirus in a human lymphoid cell line (molt-4), although the fiv-infected cells did not ... | 1996 | 8760408 |
| proviral burden and infection kinetics of feline immunodeficiency virus in lymphocyte subsets of blood and lymph node. | feline immunodeficiency virus (fiv) is similar to human immunodeficiency virus type 1 virologically and induces a clinical syndrome in cats comparable to human immunodeficiency virus type 1 syndrome in humans. to determine the lymphoid target cells of fiv, populations of cd4+ lymphocytes, cd8+ lymphocytes, and cd21+ lymphocytes (b cells) were enriched to more than 96.5% purity and then analyzed for fiv provirus by semiquantitative dna amplification. we found fiv provirus in cd4+, cd8+, and b lym ... | 1996 | 8764024 |
| studies and comparison of pterin patterns in the plasma of dogs and cats and their alteration in various neoplasias and virus infections. | physiological pterin levels were evaluated in plasma samples of healthy dogs and cats. biopterin and 7-xanthopterin were determined quantitatively by hplc after partial purification by ion exchange chromatography. neopterin, pterin and 6-hydroxymethylpterin were not detectable in plasma samples. pterin levels in plasma of dogs with neoplasias and cats with neoplasias or viral infections (felv, fiv, fip) were determined. dogs with various tumours did not show qualitative but distinct quantitative ... | 1996 | 8767729 |
| immunohistochemical findings in eyes of cats serologically positive for feline immunodeficiency virus (fiv). | in this study the eyes of 15 cats in the terminal stage of fiv infection were examined. the findings were compared to those in cats, which were euthanized because of other infectious diseases for for non-infectious reasons. thirteen fiv-infected cats showed an anterior uveitis by means of light microscopy. no accumulation of retinal lesions were found in fiv-infected cats compared to the other cats examined. additionally, there were no indications of lesions caused by opportunistic infections. i ... | 1996 | 8779812 |
| uveitis in dogs and cats: guidelines for the practitioner. | uveitis is a commonly misdiagnosed ophthalmic condition with a wide aetiological base and often the cause cannot be established. uveitis can be associated with systemic diseases like feline infectious peritonitis, feline immunodeficiency virus, feline leukaemia virus, lymphoma, toxoplasmosis and canine ehrlichiosis. the classification and general clinical signs of uveitis are discussed. applicable clinical cases, manifestations and diagnostic methods of the selected diseases are mentioned, and a ... | 1996 | 8786609 |
| [dendritic cells in dogs and cats: models of study in human pathology]. | langerhans' cells (lc) are epidermal bone-marrow-derived dendritic cells. they represent in mankind 1 to 6% of the epidermal cells from which they can be distinguished by specific phenotype (membrane receptors and antigens related to the immune function) and by ultrastructural specific organelles: the birbeck granules. in dogs and cats, such cells were recently described; they display a phenotype very similar to that of human lc (cd1, cd8, cd11/18, cd45 and mhc ii positive for canine lc, and cd1 ... | 1995 | 8786898 |
| proficiency testing of selected antigen and antibody tests for use in dogs and cats. | to determine the correlation of seroimmunologic test results between reference and nonreference laboratories. | 1996 | 8790539 |
| co-infection of toxoplasma gondii with other pathogens: pathogenicity and chemotherapy in animal models. | | 1996 | 8791703 |
| genetic and phylogenetic divergence of feline immunodeficiency virus in the puma (puma concolor). | feline immunodeficiency virus (fiv) is a lentivirus which causes an aids-like disease in domestic cats (felis catus). a number of other felid species, including the puma (puma concolor), carry a virus closely related to domestic cat fiv. serological testing revealed the presence of antibodies to fiv in 22% of 434 samples from throughout the geographic range of the puma. fiv-pco pol gene sequences isolated from pumas revealed extensive sequence diversity, greater than has been documented in the d ... | 1996 | 8794304 |
| effect of fiv infection on lung inflammatory cell populations recovered by bronchoalveolar lavage. | human immunodeficiency virus (hiv) and ovine progressive pneumonia virus have been associated with lymphocytic pneumonitis. pulmonary cell populations in cats infected with feline immunodeficiency virus (fiv) were evaluated by bronchoalveolar lavage (bal) to identify changes associated with lentivirus infection in this species. bronchoalveolar lavage was performed through an endotracheal tube using 15 ml kg-1 body weight of sterile 0.9% sodium chloride solution. results of bal fluid cytologic an ... | 1996 | 8797273 |
| changes of glutathione metabolism during feline immunodeficiency virus infection. | | 1996 | 8797692 |
| clinical and serologic evaluation of cats with cryptococcosis. | to evaluate the long-term clinical outcomes and serologic changes in cryptococcal antigen and antibody titers in cats with confirmed cryptococcus neoformans infection. | 1996 | 8800258 |
| apoptosis and cd4+ lymphocyte depletion following feline immunodeficiency virus infection of a t-lymphocyte cell line. | an interleukin-2-dependent feline t-lymphocyte cell line (fcd4-d), of which 65% of cells express cd4, was inoculated with the ncsu-1 isolate of feline immunodeficiency virus (fiv(ncsu-1)) and subsequently monitored for percentage of viable cells, percentage of apoptotic cells, percentage of cd4-expressing cells, and virus production. a decrease in viability from 91% to 12% over an 11-day postinoculation period was associated with an increase in the percentage of cells with nuclear morphology sug ... | 1996 | 8801713 |
| genetic diversity of argentine isolates of feline immunodeficiency virus. | we report the nucleotide sequence and genetic diversity of part of the envelope (env) gene of four strains of feline immunodeficiency virus (fiv) isolated from argentine domestic cats. the dna encoding the v3 to v5 regions of the env gene of the fiv isolates were amplified by pcr, cloned and sequenced. phylogenetic analysis revealed that the argentine isolates did not cluster into a single group; one isolate clustered with subtype b fiv isolated in the usa and japan, whereas the others formed a ... | 1996 | 8811000 |
| initiation of (-) strand dna synthesis from trna(3lys) on lentiviral rnas: implications of specific hiv-1 rna-trna(3lys) interactions inhibiting primer utilization by retroviral reverse transcriptases. | initiation of minus (-) strand dna synthesis was examined on templates containing r, u5, and primer-binding site regions of the human immunodeficiency virus type 1 (hiv-1), feline immunodeficiency virus (fiv), and equine infectious anemia virus (eiav) genomic rna. dna synthesis was initiated from (i) an oligoribonucleotide complementary to the primer-binding sites, (ii) synthetic trna(3lys), and (iii) natural trna(3lys), by the reverse transcriptases of hiv-1, fiv, eiav, simian immunodeficiency ... | 1996 | 8816751 |
| pulmonary and mediastinal metastases of a vaccination-site sarcoma in a cat. | sarcomas at vaccination sites in cats were first reported in 1992. recent retrospective studies have confirmed an association between these vaccination-site sarcomas (vss) and feline leukemia virus (felv) and/ or rabies vaccines. in most cases, vss are locally invasive fibrosarcomas that tend to recur but rarely metastasize. we report the mediastinal and pulmonary metastases of a vss in a felv-and feline immunodeficiency virus-negative, 8-year-old, domestic short-haired cat. the primary sarcoma ... | 1996 | 8817854 |
| incubation time for feline immunodeficiency virus cultures. | in a recent report, fiscus et al. (s. a. fiscus, s. l. welles, s. a. spector, and j. l. lathey, j. clin. microbiol. 33:246-247, 1995) have shown that qualitative human immunodeficiency virus cultures can be terminated at day 21 with minimal false-negative results. we have evaluated a large number of qualitative and quantitative feline immunodeficiency virus (fiv) isolations to determine how long fiv cultures should be incubated to obtain reasonably certain results. the rate at which fiv cultures ... | 1996 | 8818909 |
| caring for the retrovirus infected cat. | no commercial vaccine [correction of vacine] exists for feline immunodeficiency virus (fiv), and although feline leukemia virus (felv) vaccines are available, they are neither 100% effective nor used in all cats. these realities clearly indicate the veterinarian will be required to treat either felv- or fiv-positive cats for some time to come. the management of fiv- or felv-positive cats may require supportive therapies as well as virus-specific therapies such as zidovudine (azt; retrovir, burro ... | 1995 | 8820595 |
| hematologic abnormalities associated with retroviral infections in the cat. | feline patients with unexplained peripheral blood cytopenias, circulating immature or neoplastic cells, dysplastic or dysmorphic bone marrow abnormalities, and/or lymphoid tumors are likely suffering from an underlying retroviral infection with feline leukemia virus (felv) and/or feline immunodeficiency virus (fiv). cytopenic hematologic disorders are often caused by the direct or indirect hematosuppressive effects of these retroviruses. alternatively, secondary infections, nutritional deficienc ... | 1995 | 8820596 |
| opportunistic infections associated with retroviral infections in cats. | naturally occurring infection of cats with feline leukemia virus and feline immunodeficiency virus is common. a wide variety of clinical manifestations occur in retrovirus-infected cats including gastrointestinal tract disease, respiratory tract disease, central nervous system disease, ophthalmic disease, hepatic disease, urogenital tract disease, dermatologic disease, hematologic disease, and musculoskeletal disease. clinical signs are often directly attributable to the primary viral infection, ... | 1995 | 8820599 |
| feline lentivirus infection in nondomestic felids. | human immunodeficiency virus and feline immunodeficiency virus are both lentiviruses that cause immunosuppressive disease. similarities between these diseases have promoted the study of feline immunodeficiency virus as a model for human immunodeficiency virus. not only have lentiviruses been found in domestic cats but they have been found in nondomestic felids as well. florida panthers, african lions, and other nondomestic felids have been found to have antibodies directed against lentiviruses a ... | 1995 | 8820600 |
| vertical transmission of feline immunodeficiency virus. | we studied vertical transmission of feline immunodeficiency virus (fiv) to determine whether it might provide a model with which to study intervention strategies for mother-to-offspring transmission of human immunodeficiency virus (hiv). we found that pregnant cats acutely infected with fiv (fiv-csu-2771) transmitted the virus to their offspring via both prenatal and postnatal routes. in utero transmission led to several pathogenic consequences including arrested fetal development, abortion, sti ... | 1995 | 8820602 |
| reduced sensitivity to strain-specific neutralization of laboratory-adapted feline immunodeficiency virus after one passage in vivo: association with amino acid substitutions in the v4 region of the surface glycoprotein. | | 1996 | 8834468 |
| selection and characterization of a mutant of feline immunodeficiency virus resistant to 2',3'-dideoxycytidine. | we have selected and plaque purified a mutant of feline immunodeficiency virus (fiv) that is resistant to 2',3'-dideoxycytidine (ddc). this mutant was selected in cultured cells in the continuous presence of 25 microm ddc. the mutant, designated dcr-5c, was fourfold resistant to ddc, threefold resistant to 2',3'-dideoxyinosine, and more than fourfold resistant to phosphonoformic acid. dcr-5c displayed little or no resistance to (-)-beta-2',3'-dideoxy-3'-thiacytidine, 3'-azido-3'-deoxythymidine, ... | 1996 | 8849258 |
| safety of 9-(2-phosphonylmethoxyethyl)adenine (pmea) in patients with human immunodeficiency virus infection: a pilot study. | the compound 9-(2-phosphonylmethoxyethyl)adenine (pmea) is a potent inhibitor of a number of viruses in vitro such as human immunodeficiency virus types 1 and 2, herpes simplex virus types 1 and 2, hepatitis b virus, cytomegalovirus, and epstein-barr virus. pmea also proved to be effective in vivo against feline immunodeficiency virus in cats and simian immunodeficiency virus in rhesus monkeys. in an open, non-placebo-controlled trial, the safety of weekly doses of pmea in 10 patients with acqui ... | 1996 | 8861829 |
| comparative properties of feline immunodeficiency virus (fiv) and human immunodeficiency virus type 1 (hiv-1) proteinases prepared by total chemical synthesis. | the aspartyl proteinase (pr) encoded by the feline immunodeficiency virus (fiv) was prepared by total chemical synthesis. the 116-amino-acid polypeptide chain was assembled in a stepwise fashion using a boc chemistry solid-phase peptide synthesis approach and subsequently folded into the biologically active dimeric proteinase. the synthetic enzyme showed proteolytic activity against a variety of different peptide substrates corresponding to putative cleavage sites of the gag and gag-pol polyprot ... | 1996 | 8862421 |
| blood cell markers. | cytochemistry and immunocytochemistry are important adjunctive technologies to the morphologic characterization of blood cells and hematopoietic neoplasms. although cytochemistry is briefly discussed, the emphasis of this article is on the clinical application of flow cytometry and leukocyte monoclonal antibodies in veterinary medicine. classification and significance of immunophenotyping in canine and feline lymphomas and immunodeficiencies such as feline immunodeficiency virus and feline leuke ... | 1996 | 8863390 |
| neuropathology of early hiv-1 infection. | early hiv-1 invasion of the central nervous system has been demonstrated by many cerebrospinal fluid studies; however, most hiv-1 carriers remain neurologically unimpaired during the so called "asymptomatic" period lasting from seroconversion to symptomatic aids. therefore, neuropathological studies in the early pre-aids stages are very few, and the natural history of central nervous system changes in hiv-1 infection remains poorly understood. examination of brains of asymptomatic hiv-1 positive ... | 1996 | 8866743 |
| vaginal and rectal infection of cats with feline immunodeficiency virus. | the objective of this study was to examine the potential of vaginal and rectal mucosal routes for feline immunodeficiency virus (fiv) uptake and infection, as a model of mucosal hiv infection, and to determine the fate of virus at these mucosal sites following transmission of infection. spf cats were exposed to fiv isolates (pet, gl-8, t637), administered as either cell-associated or cell-free inocula, via the rectum or vagina. establishment of infection was confirmed by isolation of infectious ... | 1996 | 8870185 |
| felv, fiv testing recommendations issued. | | 1996 | 8870719 |
| env-specific ctl predominate in cats protected from feline immunodeficiency virus infection by vaccination. | animal models of hiv-1 have a key role to play in elucidation of the cellular mechanisms responsible for protective immunity. vaccination of domestic cats with whole inactivated feline immunodeficiency virus (fiv) elicits virus-neutralizing abs and virus-specific ctl in the peripheral blood and lymphoid organs and affords protection from homologous virus challenge. in the present study we confirm the induction of virus-specific ctl following immunization with whole inactivated fiv vaccine and de ... | 1996 | 8871667 |
| prevalence of antibodies to feline parvovirus, calicivirus, herpesvirus, coronavirus, and immunodeficiency virus and of feline leukemia virus antigen and the interrelationship of these viral infections in free-ranging lions in east africa. | while viral infections and their impact are well studied in domestic cats, only limited information is available on their occurrence in free-ranging lions. the goals of the present study were (i) to investigate the prevalence of antibodies to feline calicivirus (fcv), herpesvirus (fhv), coronavirus (fcov), parvovirus (fpv), and immunodeficiency virus (fiv) and of feline leukemia virus (felv) antigen in 311 serum samples collected between 1984 and 1991 from lions inhabiting tanzania's national pa ... | 1996 | 8877134 |
| mutants of feline immunodeficiency virus resistant to 2',3'-dideoxy-2',3'-didehydrothymidine. | we selected mutants of feline immunodeficiency virus (fiv) that are resistant to 2',3'-dideoxy-2',3'-didehydrothymidine (d4t). two mutants were selected in cultured cells with a stepwise increase in d4t concentration, resulting in mutants able to replicate in 100 microm d4t. these mutants were three- to sixfold more resistant to d4t than wild-type fiv. they were also cross-resistant to 3'-azido-3'-deoxythymidine (azt), 3'-fluoro-2',3'-dideoxythymidine, 2',3'-dideoxycytidine, 2',3'-dideoxyinosine ... | 1996 | 8878567 |
| the relevance of feline retroviruses to the development of vaccines against hiv. | | 1996 | 8882315 |
| vaccination of cats with recombinant envelope glycoprotein of feline immunodeficiency virus: decreased viral load after challenge infection. | | 1996 | 8882327 |
| accelerated viremia in cats vaccinated with recombinant vaccinia virus expressing envelope glycoprotein of feline immunodeficiency virus. | | 1996 | 8882329 |
| fiv monitoring project. | | 1996 | 8883354 |
| primary and secondary toxoplasma gondii infection in normal and feline immunodeficiency virus-infected cats. | normal and asymptomatic feline immunodeficiency virus (fiv)-infected adult cats were inoculated orally with toxoplasma gondii tissue cysts to assess differences in clinical disease, t. gondii serologic test results, hematologic results, and oocyst shedding. there was no difference between fiv-naive and fiv-infected cats in terms of clinical illness and duration of oocyst shedding following primary exposure. both groups of cats developed significant decreases in neutrophil counts following primar ... | 1996 | 8885881 |
| the value of primate models for studying human immunodeficiency virus pathogenesis. | research on human immunodeficiency virus (hiv) infection is compromised by the obvious limitation in having for study only virus-infected individuals or those exposed to the virus. steps involved in transmission or pathogenesis require planned experimentation. the identification of animal models of acquired immunodeficiency syndrome (aids) has therefore been helpful for evaluating phases of hiv pathogenesis. of the seven subgenera of lentiviruses now recognized, two share the characteristics wit ... | 1996 | 8892037 |
| feline immunodeficiency virus vaccination: characterization of the immune correlates of protection. | whole inactivated virus (wiv) vaccines derived from the fl4 cell line protect cats against challenge with feline immunodeficiency virus (fiv). to investigate the correlates of protective immunity induced by wiv, we established an immunization regimen which protected a proportion of the vaccinates against challenge. a strong correlation was observed between high virus neutralizing antibody titers and protection following challenge. to investigate further the immune mechanisms responsible for immu ... | 1996 | 8892875 |
| transmission of feline immunodeficiency virus in domestic cats via artificial insemination. | the objective of this study was to determine whether semen from male domestic cats infected with feline immunodeficiency virus (fiv) can transmit virus to females. twelve inseminations were performed by an intrauterine laparoscopic technique with fresh or cryopreserved electroejaculates from asymptomatic males chronically infected with the ncsu1 strain of fiv. of six inseminations performed with fresh semen, three resulted in infection of queens, as indicated by seroconversion, expression of fiv ... | 1996 | 8892958 |
| detection of apoptosis induced in peripheral blood lymphocytes from cats infected with feline immunodeficiency virus. | peripheral blood lymphocytes (pbl) from cats infected with feline immunodeficiency virus (fiv) were examined for the occurrence of apoptosis after short-term culture. in the pbl from fiv-infected cats, changes in flow-cytometry scattergram, morphological characteristics of apoptosis and nucleosomal dna fragmentation were observed. percentages of apoptotic cells by flowcytometry analysis in pbl from fiv-infected cats (22.4% +/- 9.4%) were significantly higher than those in pbl from uninfected con ... | 1996 | 8893788 |
| quasispecies and naturally occurring superinfection in feline immunodeficiency virus infection. | analysis of individual clones containing the v1 and v2 domains of the segment of the fiv env gene present in a naturally infected cat (t) was carried out. the polymerase chain reaction (pcr) was used to amplify proviral fiv dna extracted from peripheral blood mononuclear cells (pbmcs) obtained in october 1994 from this cat. the pcr products were cloned and the dna sequences determined for 11 clones. sequences obtained were aligned with sequences corresponding to fiv isolates (t90, t91, t92) prev ... | 1996 | 8893792 |
| a longitudinal study of lymphocyte subsets in a cohort of cats naturally-infected with feline immunodeficiency virus. | despite the potential of feline immunodeficiency virus (fiv) as an animal model for human immunodeficiency virus (hiv) studies, the long term effects of naturally-occurring infection have not been determined. hiv infection causes an ongoing deterioration in immune function which directly correlates with disease, in particular acquired immunodeficiency syndrome (aids). however, it is not known whether fiv-induced immunosuppression is progressive or related to the clinical condition. this study ex ... | 1996 | 8893992 |
| oral administration of bovine lactoferrin for treatment of intractable stomatitis in feline immunodeficiency virus (fiv)-positive and fiv-negative cats. | to study the effects of oral administration of bovine lactoferrin (lf) on intractable stomatitis in feline immunodeficiency virus (fiv)-positive and fiv-negative cats, and phagocytosis of neutrophils in healthy and ill cats, simultaneously. | 1996 | 8896681 |
| persistence of high virus neutralizing antibody titers in cats experimentally infected with feline immunodeficiency virus. | the development of virus neutralizing (vn) antibody is one of the most effective host defense mechanisms against virus infection. in the present study, we developed a new vn assay against feline immunodeficiency virus (fiv) using a feline t-lymphoblastoid cell line, mya-1 cells, based on inhibition of viral reverse transcriptase production. this assay is applicable to strains of fiv which can not infect crfk cells. by using the assay, we examined long-term responses of vn antibody in cats experi ... | 1996 | 8898296 |
| inhibition of the human immunodeficiency virus type 1 integrase by guanosine quartet structures. | an oligonucleotide (t30177) composed entirely of deoxyguanosine and thymidine has previously been shown to fold upon itself in the presence of potassium into a highly stable four-stranded dna structure containing two stacked deoxyguanosine quartets (g4s). t30177 also protects host cells from the cytopathic effects of human immunodeficiency virus type 1 (hiv-1). we report that this g4 oligonucleotide is the most potent inhibitor of hiv-1 integrase identified to date, with ic50 values in the nanom ... | 1996 | 8901518 |
| expression of feline immunodeficiency virus (fiv) gag gene in vaccinia virus vector. | the selected part of gag gene (nucleotide sequences at position 618 to 1724) coding for p24 and p15 proteins of feline immunodeficiency virus (fiv) was expressed in vaccinia virus vector under control of 7.5 kda vaccinia virus transtriptional signal (p 7.5 vaccinia virus early/late promoter). the vaccinia virus recombinant (denoted vv-g(1)) was generated by homologous recombination following cv-1 cells transfection with a newly prepared vaccinia virus insertion vector -- pwkr75. | 1995 | 8906935 |
| does coinfection of bartonella henselae and fiv induce clinical disorders in cats? | it was found that bartonella henselae (b. henselae) may induce clinical disorders in cats in natural conditions from a comparison of the serological status for b. henselae with the serostatus for feline immunodeficiency virus (fiv) and several clinical characteristics in 170 domestic cats. seropositivity for b. henselae was not significantly different between fiv antibody-positive and -negative cats (18.4% vs 16.0%). the incidence of clinical characteristics were compared among four cat groups d ... | 1996 | 8908605 |
| quantitation of feline immunodeficiency proviruses in doubly infected cats using competitive pcr and a fluorescence-based rflp. | a nested polymerase chain reaction assay, which amplifies a region of the gag gene, was developed for the direct detection of feline immunodeficiency virus (fiv) dna sequences in the blood of infected cats. this method detects as few as ten copies of a plasmid containing the whole genome of the fiv-pet isolate on agarose gel. to distinguish two fiv isolates in double infected cats, we devised an rflp analysis on pcr amplified products exploiting sequence differences in the gag gene of the two st ... | 1996 | 8910645 |
| immunogenicity of a peptide from a major neutralising determinant of the feline immunodeficiency virus surface glycoprotein. | the third variable region (v3) of the feline immunodeficiency virus (fiv) surface glycoprotein is predicted to have similar physical properties to that of hiv and has been shown to contain immunodominant and neutralizing epitopes. immunological characteristics of this region were investigated further using a peptide corresponding to the middle of the putative fiv v3 loop. the peptide was recognized in elisa by sera from the majority of naturally fiv-infected cats, and absorbed a significant frac ... | 1996 | 8911003 |
| antiretrovirus specificity and intracellular metabolism of 2',3' -didehydro-2',3'-dideoxythymidine (stavudine) and its 5'-monophosphate triester prodrug so324. | 2',3'-didehydro-2',3'-dideoxythymidine (d4t) and its lipophilic 5'-monophosphate triester prodrug, so324, were evaluated for their antiretroviral and metabolic properties in four different animal species cell lines. the antiretrovirus activity of so324 was approximately 4-10-fold greater than that of d4t against human immunodeficiency virus types 1 and 2 and simian immunodeficiency virus in human t lymphocyte cem and mt-4 cells and against feline immunodeficiency virus in feline crandell kidney ... | 1996 | 8913352 |
| molecular characterization of feline immunodeficiency virus genome obtained directly from organs of a naturally infected cat with marked neurological symptoms and encephalitis. | feline immunodeficiency virus (fiv) was first isolated from cats with immunodeficiency syndrome. recently, neurological abnormalities and brain lesions were shown in cats infected with fiv. to investigate the fiv genome associated with central nervous system (cns) lesions, proviral dna sequences from the v3-v6 region of the fiv env gene were directly amplified from uncultured necropsy tissues of a 2-year-old naturally fiv-infected cat with marked neurological symptoms and encephalitis. by in sit ... | 1996 | 8920826 |
| natasha's story: seeking an fiv diagnosis. | | 1996 | 8921014 |
| comparison of t-cell subpopulations in cats naturally infected with feline leukaemia virus or feline immunodeficiency virus. | t-cell subsets were studied by flow cytometry in 58 feline leukaemia virus (felv)-positive cats with naturally acquired felv infection to determine whether the changes in cd4+ or cd8+ t cell populations differed from those observed in 55 feline immunodeficiency virus (fiv)-positive cats with naturally acquired fiv infection. the sole criterion for inclusion into the study was seropositivity. mean (sd) cd4+ t cell values of felv positive cats were decreased to 31.1 (8.0) per cent and their cd8+ t ... | 1996 | 8938851 |
| two related strains of feline infectious peritonitis virus isolated from immunocompromised cats infected with a feline enteric coronavirus. | two groups of cats were experimentally infected orally with the cat-passaged rm strain of feline enteric coronavirus (fecv-rm). one group of cats (n = 19) had been chronically infected with feline immunodeficiency virus (fiv) for over 6 years, while a second control group (n = 20) consisted of fiv-naive siblings. fecal virus shedding of fecv occurred in both groups starting on day 3 postinfection, nearly ceased by 4 weeks in fiv-uninfected cats, but remained at high levels in fiv-infected animal ... | 1996 | 8940468 |
| fiv, felv, and fipv: interpretation and misinterpretation of serological test results. | serological testing is a common method of diagnosis of felina viral infections, including feline immunodeficiency virus (fiv), feline leukemia virus (felv), and feline infectious peritonitis virus (fipv). infections with these viruses can be difficult to diagnose by clinical signs alone and are sometimes clinically inapparent for months after initial exposure. serological testing to confirm a tentative diagnosis or as a screening tool for infection can be invaluable. however, serological tests m ... | 1996 | 8942210 |
| encephalitis associated with giant cells in a cat with naturally occurring feline immunodeficiency virus infection demonstrated by in situ hybridization. | this report describes the clinical, pathological, immunocytochemical, and in situ hybridization characteristics of encephalitis associated with feline immunodeficiency virus (fiv) infection in a 4-year-old domestic cat. lesions were identified throughout the brain, affecting the cerebrum, medulla, and cervical spinal cord. perivascular lymphocytic cuffing, gliosis, and white matter vacuolation were most severe in the cerebrum, affecting the white matter and the deep laminae of the grey matter. g ... | 1996 | 8952030 |
| vaccination with fixed feline immunodeficiency virus (fiv) infected cells: protection, breakthrough and specificity of response. | infection of cats with feline immunodeficiency virus (fiv), a naturally occurring lentivirus infection of cats which causes an aids-like disease, has generated considerable interest as an animal model for hiv vaccination. this paper reports on experiments performed to examine the potential of a fixed infected cell vaccine to confer protection against intraperitoneal challenge with cell-free fiv. the cell vaccine was highly immunogenic and elicited antibody responses to virus core antigen, p24, h ... | 1996 | 8961513 |
| relationship of lower urinary tract signs to seropositivity for feline immunodeficiency virus in cats. | a group of 41 cats with signs of lower urinary tract disease was compared to a group of 41 cats without any history of disease for prevalence of seropositivity for feline immunodeficiency virus (fiv). the group of healthy cats was similar in age and gender to the group of cats with signs of lower urinary tract disease. three of the cats with lower urinary tract disease and one control cat were seropositive for fiv. this difference was not statistically significant. the most common cause of lower ... | 1996 | 8965266 |
| roles of the auxiliary genes and ap-1 binding site in the long terminal repeat of feline immunodeficiency virus in the early stage of infection in cats. | to examine the roles of auxiliary genes and the ap-1 binding site in the long terminal repeat of feline immunodeficiency virus (fiv) in vivo, three mutant viruses, which are defective in the vif gene ([delta]vif), orf-a gene (deltaorf-a), and ap-1 binding site (deltaap-1), and wild-type virus as a positive control were separately inoculated into three specific-pathogen-free cats. these cats were assessed by measuring the number of proviral dna copies in peripheral blood mononuclear cells (pbmcs) ... | 1996 | 8970975 |
| virus load and neuropathology in the fiv model. | the fiv (feline immunodeficiency virus) induces in cats brain changes presenting similarities with those observed in human immunodeficiency virus infection. this fiv model was used to study the relationship between viral load in brain, in lymphoid organs and central nervous system (cns) changes during the early and late stages of infection. early brain changes were analyzed in animals experimentally infected with two different fiv isolates and sacrificed at 7 and 15 days, 1, 2, 6, and 12 months ... | 1996 | 8972419 |
| neurologic dysfunctions caused by a molecular clone of feline immunodeficiency virus, fiv-ppr. | fiv is a lentivirus of domestic cats that causes a spectrum of diseases that is remarkably similar to the clinical syndrome produced by hiv infection in people. both hiv and fiv has been shown to cause neurologic dysfunction. specific pathogen-free (spf) cats were placed into one of three groups: fiv-ppr infected; du-fiv-ppr (a dutpase mutant of the fiv-ppr clone) infected; or an age-matched control group. in both infected groups, the general clinical signs of infection included lymphadenopathy, ... | 1996 | 8972420 |
| crystal structure of dutp pyrophosphatase from feline immunodeficiency virus. | we have determined the crystal structure of dutp pyrophosphatase (dutpase) from feline immunodeficiency virus (fiv) at 1.9 a resolution. the structure has been solved by the multiple isomorphous replacement (mir) method using a p6(3) crystal form. the results show that the enzyme is a trimer of 14.3 kda subunits with marked structural similarity to e. coli dutpase. in both enzymes the c-terminal strand of an anti-parallel beta-barrel participates in the beta-sheet of an adjacent subunit to form ... | 1996 | 8976551 |
| clinical evaluation of cats with nonobstructive urinary tract diseases. | to identify the underlying cause of clinical signs in cats with nonobstructive diseases of the bladder and urethra. | 1997 | 8977647 |
| diagnostic evaluation of cats with seizure disorders: 30 cases (1991-1993). | to investigate causes of seizure disorders in cats. | 1997 | 8977651 |
| [quantification of feline immunodeficiency virus (fiv) rna in the plasma of infected cats]. | a competitive reverse transcription-polymerase chain reaction (rt-pcr) was used to quantify rna of feline immunodeficiency virus (fiv) in cats. the assay uses in vitro synthesized rna as a competitive internal control. the synthesized rna has a 22-base deletion with respect to the wild-type sequence. pcr products were quantitated by densitometric analysis of a digitized image of the ethidium bromide stained gel. viral rna concentrations in the plasma of two cats experimentally infected with fiv ... | 1996 | 9005834 |
| parameters of disease progression in long-term experimental feline retrovirus (feline immunodeficiency virus and feline leukemia virus) infections: hematology, clinical chemistry, and lymphocyte subsets. | after several years of latency, feline immunodeficiency virus (fiv) and feline leukemia virus (felv) cause fatal disease in the cat. the aim of this study was to determine laboratory parameters characteristic of disease progression which would allow a better description of the asymptomatic phase and a better understanding of the pathogenesis of the two infections. therefore, experimentally infected cats (fiv and/or felv positive) and control animals were observed over a period of 6.5 years under ... | 1997 | 9008278 |
| molecular characterization of virus-specific rna produced in the brains of flavivirus-susceptible and -resistant mice after challenge with murray valley encephalitis virus. | natural resistance to flaviviruses in mice is controlled by a single genetic locus, fiv, on chromosome 5. although the mechanism of this resistance is not fully understood, it is believed to operate at the level of virus replication rather than the immune response. it has been hypothesized that enhanced production of viral defective interfering (di) particles is responsible for a substantial reduction in the titres of infectious virus in resistant mice. however, this has never been established a ... | 1997 | 9010281 |
| common mechanism of infection by lentiviruses. | | 1997 | 9024654 |
| proviral organization and sequence analysis of feline immunodeficiency virus isolated from a pallas' cat. | the nucleotide sequence and genomic organization have been determined for a highly cytopathic feline immunodeficiency virus (fiv) isolated from a pallas' cat. the 9747-bp provirus of this virus, fiv-oma, has typical lentivirus organization with ltrs, gag, pol, and env open reading frames (orfs), putative vif and rev orfs, and an orf similar to orf2/orfa of domestic cat fiv isolates. although the fiv-oma provirus is 300 to 600 bp longer than other fiv proviruses, these additional bases are distri ... | 1997 | 9024812 |
| detection of proviruses and viral rna in the early stages of feline immunodeficiency virus infection in cats: a possible model of the early stage of hiv infection. | feline immunodeficiency virus (fiv) infection in cats has been reported to be a useful animal model for human aids studies, especially in the early stages of infection. we examined the temporal changes in provirus detection in peripheral blood mononuclear cells (pbmc) and the distribution of fiv-dna and rna in feline tissues by the polymerase chain reaction at 10, 35, 70 days after intravenous inoculation of fiv. viral dna in the pbmc was detected three to four weeks after infection and its fluc ... | 1997 | 9027469 |
| a novel met-to-thr mutation in the ymdd motif of reverse transcriptase from feline immunodeficiency virus confers resistance to oxathiolane nucleosides. | variants of feline immunodeficiency virus (fiv) that possess a unique methionine-to-threonine mutation within the ymdd motif of reverse transcriptase (rt) were selected by culturing virus in the presence of inhibitory concentrations of (-)-beta-l-2',3'-dideoxy-5-fluoro-3'-thiacytidine [(-)-ftc]. the mutants were resistant to (-)-ftc and (-)-beta-l-2',3'-dideoxy-3'-thiacytidine (3tc) and additionally exhibited low-level resistance to 2',3'-dideoxycytidine (ddc). dna sequence analysis of the rt-en ... | 1997 | 9032372 |
| evidence of infection with feline immunodeficiency virus among danish cats between 1970 and 1974. | | 1997 | 9032911 |
| [liberation into the wild of wild felines--danger of the release of virus infections]. | there are several felidae amongst the numerous endangered species. means of aiding survival are the reintroduction to the wild of animals bred under the auspices of man and their relocation from densely populated to thinly populated areas. it is unlikely that the dangers of such reintroduction or relocation projects have been examined sufficiently in respect to the risks of virus infections confronting individuals kept in zoos or similar situations. this report presents three examples to illustr ... | 1996 | 9045289 |
| inhibition of feline immunodeficiency virus infection by cd9 antibody operates after virus entry and is independent of virus tropism. | a monoclonal antibody which blocks infection with feline immunodeficiency virus (fiv) was found previously to react with the cell surface molecule cd9, implicating cd9 in the process of virus entry. we report here that inhibition by anti-cd9 antibody does not operate at the level of virus entry but at a subsequent stage in the virus life-cycle. moreover, inhibition of infection is independent of the passage history of the virus or the virus subtype. inhibition of fiv infection by anti-cd9 antibo ... | 1997 | 9049412 |
| detection of feline immunodeficiency virus transcripts by quantitative reverse transcription-polymerase chain reaction. | we developed a quantitative reverse transcription-polymerase chain reaction (rt-pcr) procedure to estimate replication status of feline immunodeficiency virus (fiv) in peripheral blood mononuclear cells (pbmcs) of cats. primers used for the rt-pcr were designed to detect only multiple spliced transcripts of fiv and allowed us to detect the specific transcripts with high specificity. by using limiting-cell-dilution rt-pcr, we demonstrated that the specific transcripts were quantitatively detected ... | 1996 | 9054129 |