| selective inhibition of human immunodeficiency viruses by racemates and enantiomers of cis-5-fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine. | 2',3'-dideoxy-5-fluoro-3'-thiacytidine (ftc) has been shown to be a potent and selective compound against human immunodeficiency virus type 1 in acutely infected primary human lymphocytes. ftc is also active against human immunodeficiency virus type 2, simian immunodeficiency virus, and feline immunodeficiency virus in various cell culture systems, including human monocytes. the antiviral activity can be prevented by 2'-deoxycytidine, but not by other natural nucleosides, suggesting that ftc mus ... | 1992 | 1283296 |
| isolation and partial characterization of infectious molecular clones of feline immunodeficiency virus obtained directly from bone marrow dna of a naturally infected cat. | replication-competent molecular clones of feline immunodeficiency virus (fiv) were isolated directly from the dna of bone marrow cells of a naturally fiv-infected cat. after transfection in a feline kidney cell line (crfk) and subsequent cocultivation with peripheral blood mononuclear cells (pbmc), the viral progeny of the clones was infectious for pbmc but not for crfk cells. pbmc infected with these clones showed syncytium formation, a decrease in cell viability, and gradual loss of cd4+ cells ... | 1992 | 1309891 |
| expression of feline immunodeficiency virus gag gene in escherichia coli. | the gag gene of a japanese feline immunodeficiency virus (fiv) isolate, designated as fiv tm 2, was expressed in escherichia coli as a fusion protein with trpe. using this expressed protein, an enzyme-linked immunosorbent assay was developed for detection of antibodies to fiv gag protein in feline sera. with serum samples from a cat experimentally infected with fiv, it was demonstrated that the period of seroconversion detected by this method corresponded to that by western blotting. | 1992 | 1309999 |
| identification and analysis of the gag-pol ribosomal frameshift site of feline immunodeficiency virus. | the pol genes of retroviruses are translated as gag-pol fusion proteins by ribosomal frameshifting within the gag-pol overlap region. during the ribosomal frameshift event, the gag open reading frame is shifted -1 nt to allow in-phase reading of the pol open reading frame. a consensus frameshift signal sequence of gggaaac within the gag-pol overlap region of feline immunodeficiency virus (fiv) has been identified followed by a sequence that has the potential for a pseudoknot tertiary structure. ... | 1992 | 1310175 |
| regulation of gene expression directed by the long terminal repeat of the feline immunodeficiency virus. | the long terminal repeat (ltr) of a retrovirus contains sequence elements that constitute a promoter for controlling viral gene expression in infected cells. we have examined regulation of ltr-directed gene expression in feline immunodeficiency virus (fiv), a t-lymphocytopathic lentivirus associated with a fatal aids-like disease in domestic cats. two independent virus isolates, designated fiv-petaluma and fiv-ppr, have been molecularly cloned and show greater than 85% sequence homology. both cl ... | 1992 | 1310554 |
| decline in cd4+ cell numbers in cats with naturally acquired feline immunodeficiency virus infection. | t-cell subsets were studied by fluorescence-activated cell sorter analysis in 57 feline immunodeficiency virus (fiv)-seropositive cats with naturally acquired fiv infection to see whether cd4(+)-cd8+ alterations were comparable to those observed in human immunodeficiency virus-infected patients. cd4+ values were decreased and cd8+ values were increased. the cd4+/cd8+ ratio was reduced to 1.6, compared with 3.3 in 33 fiv-seronegative control cats. variance analysis of data showed a significant in ... | 1992 | 1310760 |
| distinct subsets of retroviruses encode dutpase. | the nonprimate lentiviruses feline immunodeficiency virus, equine infectious anemia virus, visna virus, and caprine encephalitis virus contain a gene segment in the polymerase gene that is lacking in the primate lentiviruses. a related sequence has been noted in other retroviruses, most notably the type d retroviruses. computer searches have indicated a relatedness between this unique gene segment, termed proteaselike element and elements of both the aspartate proteinase and the dutpase enzyme f ... | 1992 | 1310783 |
| molecular characterization and heterogeneity of feline immunodeficiency virus isolates. | we have molecularly cloned the complete genomic dna of tm2 strain of feline immunodeficiency virus (fiv) isolated in japan and compared its nucleotide and the deduced amino acid sequence with those of previously described u.s. isolates, fiv petaluma and fiv ppr. the infectious molecular clone of fiv tm2 is different from fiv petaluma in host cell range; the clone can not infect crandell feline kidney cells which were permissive for fiv petaluma. the amino acid sequence homologies, in gag, pol, a ... | 1992 | 1312825 |
| feline immunodeficiency virus and tests for hiv. | | 1992 | 1313615 |
| detection of feline immunodeficiency proviral dna in peripheral blood lymphocytes by the polymerase chain reaction. | feline immunodeficiency virus (fiv) proviral dna was detected by the polymerase chain reaction method (pcr). pcr products were detected by gel electrophoresis and ethidium bromide staining. the p-10, p-15 and p-24 regions of the gag gene of fiv were chosen as the target sequences for amplification, and three primer pairs were prepared. the pcr products subjected to amplification with each primer pair were found to possess sites of digestion by a restriction enzyme, as hypothesized. they did not ... | 1992 | 1313618 |
| further characterization of a feline t-lymphoblastoid cell line (mya-1 cells) highly sensitive for feline immunodeficiency virus. | | 1992 | 1313703 |
| comparison of the viral promoter activities in feline cell lines (crfk and fcwf-4 cells). | | 1992 | 1313705 |
| detection of feline immunodeficiency virus by a nested polymerase chain reaction. | a specific and sensitive polymerase chain reaction (pcr) procedure for the detection of feline immunodeficiency virus (fiv) in peripheral blood mononuclear cells (pbmc) was developed. pbmc from both blood samples and cultures were digested by proteinase k in a lysis buffer, and after heat inactivation of the proteinase, the resultant material was used in a two step amplification protocol using nested sets of primers. two independent amplifications, from the gag and pol genes respectively, were p ... | 1992 | 1313823 |
| cell-specific envelope glycosylation distinguishes fiv glycoproteins produced in cytopathically and noncytopathically infected cells. | feline immunodeficiency virus (fiv) infection induces syncytium formation and cell death in primary feline astrocyte cultures but persistently and noncytopathically infects crandell feline kidney cells (crfk). because viral envelope glycoproteins are implicated in cell fusion events we evaluated the astrocyte-produced fiv surface glycoprotein for properties that might distinguish it from that produced in crfk cells. the surface glycoprotein from astrocytes migrated faster on sds-page and contain ... | 1992 | 1314453 |
| prevalence of feline leukemia virus and antibodies to feline immunodeficiency virus in cats in norway. | serum samples from 224 norwegian cats were analyzed for the presence of feline leukemia virus (felv) p27 common core antigen, and for antibodies to feline immunodeficiency virus (fiv). ninety specimens originated from the serum bank at the central referral clinic at the norwegian college of veterinary medicine, which had been collected during the years 1983-1989; 67 sera were submitted from veterinarian practitioners; while 67 sera originated from cats presented for euthanasia. the cats were cla ... | 1992 | 1316024 |
| prevalence of feline immunodeficiency virus and other retroviral infections in sick cats in italy. | two hundred and seventy-seven sick pet cats living in italy were tested for antibodies to feline immunodeficiency virus (fiv) and for feline leukemia virus (felv) antigen. overall, 24% of the cats resulted positive for anti-fiv antibody and 18% for felv antigen. fiv was isolated from the peripheral mononuclear blood cells of ten out of 15 seropositive cats examined and from one out of eight saliva samples. no fiv isolations were obtained from six serum samples cultured. feline syncytium forming ... | 1992 | 1317073 |
| lymphosarcoma in experimentally induced feline immunodeficiency virus infection [corrected]. | a cat experimentally infected with feline immunodeficiency virus (fiv) but known to be free of feline leukaemia virus (felv) developed lymphosarcoma. the lesions in the liver and kidneys were present nine months after infection, when the cat was 21 months old. the cat had no overt signs of immunodeficiency and it is suggested that the b cell activation induced shortly after fiv infection produced a large pool of proliferating lymphocytes from which the malignant cells emerged. | 1992 | 1317615 |
| a survey of fiv antibodies and felv antigens in free-roaming cats in the capital area of finland. | feline immunodeficiency virus (fiv) was first isolated and identified in 1986. since then it has been shown to have a worldwide distribution, and the infection generally appears to have reached a state of endemicity. this is the 1st study of fiv-prevalence in finland. serum samples of 196 free-roaming cats were tested for antibodies to fiv and felv antigens (feline leukemia virus). with a combined enzyme-linked immunosorbent assay (elisa), 13 of the cats (6.6%) turned out to be positive for fiv ... | 1992 | 1317991 |
| detection of feline immunodeficiency virus (fiv) nucleic acids in fiv-seronegative cats. | a study was undertaken to determine the rate of viral transmission among naive specific-pathogen-free (spf) cats living in close contact with feline immunodeficiency virus (fiv)-infected cats. twenty spf cats were housed in the same rooms with experimentally fiv-infected seropositive and virus culture-positive cats for 2 to 4 years and were monitored for the presence of fiv nucleic acids and antibodies. only 1 of the 20 cats became seropositive and virus culture positive and developed signs of d ... | 1992 | 1318395 |
| detection of anti-gag antibodies of feline immunodeficiency virus in cat sera by enzyme-linked immunosorbent assay. | using gag protein of feline immunodeficiency virus (fiv) expressed in escherichia coli, an enzyme-linked immunosorbent assay (elisa) system was developed for detection of antibodies to fiv gag protein in cat sera. with serum samples from cats experimentally infected with several strains and an infectious molecular clone of fiv, increases of the antibody titers to fiv gag protein were observed in all cases by the elisa at early stage of infection. when we examined a total of 415 field cat sera wh ... | 1992 | 1318710 |
| production of feline immunodeficiency virus in feline and non-feline non-lymphoid cell lines by transfection of an infectious molecular clone. | an infectious molecular clone of the tm1 strain of feline immunodeficiency virus (fiv) was transfected into each of one feline (crfk), two simian (cos and vero) and two human (sw480 and hela) non-lymphoid cell lines, and virus production was assayed on feline t lymphoblastoid mya-1 cells by monitoring reverse transcriptase activity. infectious virus was produced in crfk, vero and hela cells, but not in cos and sw480 cells. when the basal promoter activity of the fiv long terminal repeat (ltr) wa ... | 1992 | 1318947 |
| [trichomonad infections of the oral cavity in cats in south germany]. | in this investigation trichomonads were isolated from the oral cavity in 21 of 110 examined cats, and only from those which were simultaneously felv, fiv or fip positive. by means of scanning electron microscopy the trichomonads were shown to be round or piriform parasites which were on average 7.9 microns long and 6.2 microns wide at maximum width. they had 4 anterior flagella, which were on average 9.4 microns long, an undulating membrane measuring 6.7 microns with no trailing flagellum as wel ... | 1992 | 1319091 |
| comparison of early and late feline immunodeficiency virus encephalopathies. | the study of the early and late stages of encephalopathy following infection by the feline immunodeficiency virus (fiv) was carried out with laboratory and naturally infected cats. | 1992 | 1319717 |
| papillomavirus associated skin lesions in a cat seropositive for feline immunodeficiency virus. | a cat was presented with skin lesions consisting of slightly raised pigmented plaques, 2-7 mm in diameter with a rough slightly verrucous surface. histologically these lesions were identified as papillomas. a papillomavirus infection was demonstrated: virus-like particles were present in the nuclei of cells within the lesions, and staining with an anti-bovine papillomavirus (bpv-1) antibody was obtained. an infection with feline immunodeficiency virus was diagnosed in this cat; this condition ha ... | 1992 | 1320786 |
| macrophage functions in cats experimentally infected with feline immunodeficiency virus and toxoplasma gondii. | it was suspected that feline immunodeficiency virus (fiv) infection would affect the function of feline macrophages, and that the concomitant infection of cats with fiv and toxoplasma gondii would cause even greater changes in macrophage function. sixteen specific-pathogen-free kittens, four per group, were infected either with fiv, t. gondii, both pathogens, or neither pathogen. after the cats had been infected with fiv for 14 weeks (8 weeks after t. gondii infection), peritoneal macrophages we ... | 1992 | 1321533 |
| simple in vitro methods for titrating feline immunodeficiency virus (fiv) and fiv neutralizing antibodies. | the feline immunodeficiency virus (fiv) readily produced syncytia in crandell feline kidney (crfk) cells adapted to a medium containing 0.5% fetal calf serum, a variety of growth factors and other supplements. this finding has been exploited to develop simple and sensitive virus titration and neutralization assays. high titre neutralizing antibodies were detected in cats infected naturally and experimentally with fiv, but not in uninfected animals. | 1992 | 1321834 |
| [kittens and felv]. | | 1992 | 1322571 |
| replicative difference in early-passage feline brain cells among feline immunodeficiency virus isolates. | the susceptibility of early-passage feline brain cells and crandell feline kidney (crfk) cells to infection with three isolates of feline immunodeficiency virus (fiv) was investigated. the petaluma strain of fiv could well infect both the feline brain cells and crfk cells. the kyo-1 strain could well infect the feline brain cells but the replication in crfk cells was demonstrated only by coculturing fresh feline t-lymphoblastoid cells with the infected cells. on the other hand, the tm1 strain co ... | 1992 | 1322657 |
| altered surface antigen expression on peripheral blood mononuclear cells in cats infected with feline immunodeficiency virus. | expression of cd4, cd8, il-2 receptor alpha chain (il-2r alpha), and mhc class ii (mhc-ii) on peripheral blood mononuclear cells were examined in cats infected with feline immunodeficiency virus (fiv). cd4/cd8 t cell ratio in fiv-infected cats was slightly decreased, as compared with that in specific-pathogen-free (spf) cats. however, there was no statistical differences between them. the number of circulating il-2r alpha+ cells in fiv-infected cats was higher than that in healthy cats, whereas ... | 1992 | 1322715 |
| humoral immune response to feline immunodeficiency virus in cats with experimentally induced and naturally acquired infections. | sera from cats with naturally acquired and experimentally induced feline immunodeficiency virus (fiv) infections were tested by immunoblot analysis, radioimmunoprecipitation assay (ripa), and a complex trapping/blocking elisa. in sequentially obtained samples from experimentally inoculated cats, antibodies against the envelope protein gp120 and the core protein p15 were the first to appear, as indicated by results of ripa, using lysates of fiv-infected lymphocytes. antibodies could be detected a ... | 1992 | 1323226 |
| detection of salivary antibodies in cats infected with feline immunodeficiency virus. | the saliva of cats infected with feline immunodeficiency virus was examined for total immunoglobulin content and antiviral antibodies. seropositive cats showed an increase in salivary immunoglobulin g levels, which was only partly attributable to the enhanced prevalence of oral inflammatory lesions, compared with the levels in seronegative cats. immunoglobulin g, but not immunoglobulin m, levels in serum were also increased. salivary antibodies were determined by indirect immunofluorescence and ... | 1992 | 1323574 |
| induction of feline immunodeficiency virus-specific cytolytic t-cell responses from experimentally infected cats. | we have examined the in vitro induction and activity of feline immunodeficiency virus (fiv)-specific cytolytic t cells obtained from cats experimentally infected for 7 to 17 weeks or 20 to 22 months with the petaluma isolate of fiv. normal or fiv-infected autologous and allogeneic t lymphoblastoid cells were used as target cells in chromium-51 or indium-111 release assays. when effector cells consisted of either fresh peripheral blood mononuclear cells or concanavalin a- and interleukin-2-stimul ... | 1992 | 1323704 |
| identification of the rev transactivation and rev-responsive elements of feline immunodeficiency virus. | spliced messages encoded by two distinct strains of feline immunodeficiency virus (fiv) were identified. two of the cdna clones represented mrnas with bicistronic capacity. the first coding exon contained a short open reading frame (orf) of unknown function, designated orf 2. after a translational stop, this exon contained the l region of the env orf. the l region resides 5' to the predicted leader sequence of env. the second coding exon contained the h orf, which began 3' to env and extended in ... | 1992 | 1323707 |
| mycological findings in feline immunodeficiency virus-infected cats. | thirty-five fiv-seropositive cats and 55 fiv-seronegative matched cats were examined for yeasts (oropharyngeal swabs) and dermatophytes (hair brushings). the frequency of isolation of candida albicans and cryptococcus neoformans was significantly higher in the former group. the only dermatophyte isolated was microsporum canis. its prevalence was three times higher among fiv-infected cats than among control animals. | 1992 | 1325555 |
| analysis of the amino terminal presequence of the feline immunodeficiency virus glycoprotein: effect of deletions on the intracellular transport of gp95. | the envelope glycoprotein of feline immunodeficiency virus (fiv) consists of two noncovalently associated subunits, the surface glycoprotein (su; gp95) and the transmembrane glycoprotein (tm; gp40). an unusual feature of the open reading frame (orf) encoding the fiv glycoprotein is the presence of an unusually long amino terminal sequence (149 amino acids, "l" region or n-region of the signal sequence) preceding the predicted hydrophobic signal sequence. to examine the role of this n-region in t ... | 1992 | 1325696 |
| major core proteins, p24s, of human, simian, and feline immunodeficiency viruses are partly expressed on the surface of the virus-infected cells. | we have previously shown the expression of human immunodeficiency virus type 1 (hiv-1) major gag protein, p24, on the surface of persistently hiv-1-infected cells by using murine monoclonal antibodies (mab). we now report that the cell surface gag p24 antigen expression is a universal phenomenon among hiv-1, simian immunodeficiency virus (siv), and feline immunodeficiency virus (fiv). the mabs prepared by immunization with purified hiv-1 particles were used as antibodies cross-reactive to hiv-1 ... | 1992 | 1326145 |
| sequences within the feline immunodeficiency virus long terminal repeat that regulate gene expression and respond to activation by feline herpesvirus type 1. | we constructed a series of deletion mutants of feline immunodeficiency virus (fiv) long terminal repeat (ltr) to identify the regions that regulate gene expression and are responsive to trans-activation of fiv ltr by feline herpes-virus type 1 (fhv-1). we demonstrated that sequences between -124 and -79, and between -21 and -32 (relative to the cap site) are essential for gene expression of fiv in felis catus whole fetus 4 (fcwf-4) cells. further, we demonstrated that the sequence between -63 an ... | 1992 | 1326814 |
| feline immunodeficiency virus--aids in cats? | | 1992 | 1330199 |
| feline immunodeficiency virus: a brief review. | feline immunodeficiency virus (fiv), previously known as feline t-lymphotropic lentivirus (ftlv), was first described by pedersen et al. (1987) who isolated the virus from cats with a variety of clinical signs suggestive of immunodeficiency. since then fiv has become one of the most studied feline viruses, not least because of its similarity to human immunodeficiency viruses (hiv) which cause acquired immunodeficiency syndrome (aids) in man. | 1992 | 1330201 |
| antibody responses to toxoplasma gondii antigens in aqueous and cerebrospinal fluids of cats infected with t. gondii and fiv. | antibodies to antigens of toxoplasma gondii were measured in the aqueous and cerebrospinal fluid (csf) of 16 specific-pathogen free kittens experimentally infected with feline immunodeficiency virus (fiv), t. gondii, or both pathogens. the results indicated that all cats infected with t. gondii had antibody responses to antigens of t. gondii in both aqueous fluids and csf. co-infection with fiv did not affect antibody levels. aqueous fluids from eyes of cats with toxoplasmic retinochoroiditis di ... | 1992 | 1330426 |
| retrospective serologic survey for the presence of feline immunodeficiency virus antibody: a comparison of elisa and ifa techniques. | a total of 878 samples from the new york state diagnostic laboratory (nysdl), dating from january 1984 to may 1987, were examined to detect antibodies to feline immunodeficiency virus (fiv). we used 2 screening methods; an indirect immunofluorescence assay (ifa) and an enzyme-linked immunosorbent assay (elisa). of these, 211 samples were from cats that tested negative for feline leukemia virus (felv) and exhibited disease signs consistent with immunodeficiency disease; 19 (9.0%) serum samples we ... | 1992 | 1330430 |
| serologic prevalence of selected infectious diseases in cats with uveitis. | serologic evidence of infection by toxoplasma gondii, feline leukemia virus, feline coronaviruses, or feline immunodeficiency virus (fiv) is commonly found in cats with uveitis. serum samples from 124 cats with uveitis were assayed by use of elisa for the detection of t gondii-specific immunoglobulin m (igm), igg, and circulating antigens (ag), as well as an elisa for feline leukemia virus ag, an elisa for antibodies to fiv, and an indirect fluorescent antibody assay for antibodies to feline cor ... | 1992 | 1330998 |
| no evidence of vertical transmission of naturally acquired feline immunodeficiency virus infection. | a naturally occurring feline immunodeficiency virus (fiv) infection in a closed breeding colony of cats, was studied for a period of 9 months. the colony consisted of 25 adult cats, of which six proved to be infected with fiv as judged by serological examination and virus isolation. in all, 48 kittens were monitored for levels of antibodies against fiv during their first 6 months of life. all the kittens (n = 30) born of fiv-infected queens showed maternal antibodies against fiv, although these ... | 1992 | 1332250 |
| anti-human immunodeficiency virus (hiv) agents are also potent and selective inhibitors of feline immunodeficiency virus (fiv)-induced cytopathic effect: development of a new method for screening of anti-fiv substances in vitro. | the ability of several known anti-hiv substances to inhibit feline immunodeficiency virus (fiv) was tested. the results showed that fiv infection of feline t-cells was almost completely blocked in the presence of all of the agents tested. however, fiv-induced syncytium formation between a human t-cell line (mt-2 cells) and a fiv-infected feline lymphocyte cell line (3201/fiv) was inhibited only by dextran sulfate and pradimicin a. the assay used to measure syncytium inhibition was rapid and did ... | 1992 | 1332602 |
| cryptococcosis in two cats seropositive for feline immunodeficiency virus. | | 1992 | 1333667 |
| feline immunodeficiency virus: quantification in peripheral blood mononuclear cells and isolation from plasma of infected cats. | the titer of feline immunodeficiency virus in peripheral blood mononuclear cells (pbmc) and the presence of infectious virus in plasma was investigated over 20 week period in 8 experimentally infected cats, 3 uninfected cats and 2 naturally infected cats by end point dilution cultures using a feline t-lymphoblastoid cell line (mya-1). fiv was isolated from pbmc of all infected cats, but not from the uninfected cats. fiv was also isolated consistently from 100 microliters plasma from most of the ... | 1992 | 1333753 |
| toxoplasma gondii: an aids enhancing cofactor. | disseminated toxoplasmosis, one of the most severe acquired immune deficiency syndrome (aids)-associated infections in humans, is believed to develop from a latent infection after the cellular immune system is suppressed by human immunodeficiency virus type 1 (hiv-1). however, toxoplasma gondii may serve as a cofactor in enhancing the immunodeficiency induced by hiv-1. this hypothesis is supported by the facts that: 1) co-infection with other pathogens in humans infected with hiv-1 may enhance t ... | 1992 | 1334211 |
| animal immunodeficiency viruses. | feline immunodeficiency virus (fiv) has morphological, physical and biochemical characteristics similar to human immunodeficiency virus (hiv), the cause of aids in man. however, it is antigenically and genetically distinct from hiv; an antigenic relatedness with equine infectious anaemia virus has been demonstrated. fiv has been molecularly cloned and sequenced. diagnostic tests are commercially available and attempts at preparing inactivated, subunit and molecularly engineered vaccines are bein ... | 1992 | 1336243 |
| identification and evaluation of new primer sets for the detection of lentivirus proviral dna. | we have developed sets of degenerate oligonucleotides designed to detect pol gene sequences from any member of the lentivirus subfamily when used as primers in amplification techniques such as the polymerase chain reaction (pcr). this pan-lentivirus-specific primer set (plsps) consists of primers, lv1, lv2, and lv3, based on conserved regions common to lentiviruses only. our protocol is based on primary amplification with lv1 and lv2 followed by secondary amplification with a nested primer set b ... | 1992 | 1337258 |
| a recombinant-based feline immunodeficiency virus antibody enzyme-linked immunosorbent assay. | we have developed an antibody detection enzyme-linked immunosorbent assay (elisa) for the identification of animals infected by feline immunodeficiency virus (fiv). the elisa solid-phase antigen consists of recombinant fiv gag proteins expressed in bacteria. the proteins are purified from bacterial lysates as insoluble inclusion bodies. in the case of bacterially expressed p24gag, it is shown that all of the linear, sequential epitopes presented by viral p24 during infection are retained. purifi ... | 1992 | 1337392 |
| a recombinant feline immunodeficiency virus envelope fusion protein stimulates peripheral blood lymphocytes from naive cats to proliferate in vitro. | a region of feline immunodeficiency virus (fiv)/glasgow-8 external envelope glycoprotein (env) incorporating the third and fourth variable regions (v3/v4) was cloned, inserted into the pgex vector and expressed in escherichia coli to yield milligram quantities of the recombinant polypeptide as a fusion protein with glutathione s-transferase. the fusion protein v3/v4gst was used in lymphocyte proliferation assays, where it consistently caused peripheral blood lymphocytes from naive cats to prolif ... | 1992 | 1337393 |
| long-term clinical observations on feline immunodeficiency virus infected asymptomatic carriers. | eleven feline immunodeficiency virus (fiv) infected asymptomatic carrier (ac) cats were observed for 2 years for development of acquired immunodeficiency syndrome (aids). four of the 11 (36.4%) showed progression of the clinical stage. persistent generalized lymphadenopathy was noted in three cats as the first sign of illness after the ac phase, while the other showed lymphadenopathy with signs of aids-related complex. in all four cats the aids-related complex stage lasted for 10 months or longe ... | 1992 | 1337394 |
| evaluation of 9-(2-phosphonylmethoxyethyl) adenine therapy for feline immunodeficiency virus using a quantitative polymerase chain reaction. | to determine the efficacy of 9-(2-phosphonylmethoxyethyl)adenine (pmea) as a prophylactic chemotherapeutic agent for the treatment of lentivirus infections, three groups of specific pathogen free cats were treated with 0, 3, or 6 mg kg-1 twice daily doses of pmea beginning 24 h prior to virus challenge with feline immunodeficiency virus petaluma strain. treatment was continued for 7 weeks post challenge. during this time cats were monitored for drug toxicity, virus specific antibody response, ci ... | 1992 | 1337395 |
| pilot study of the effect of acemannan in cats infected with feline immunodeficiency virus. | acemannan, a complex carbohydrate shown to stimulate interleukin-1, tumor necrosis factor alpha and prostaglandin e2 production by macrophages, has also demonstrated antiviral activity in vitro against human immunodeficiency virus, newcastle disease virus and influenza virus. a pilot study was undertaken to determine acemannan's effect in 49 feline immunodeficiency virus (fiv) infected cats with clinical signs of disease (stage 3, 4 or 5), 23 of which had severe lymphopenia. cats received aceman ... | 1992 | 1337396 |
| enhancement after feline immunodeficiency virus vaccination. | cats were vaccinated with one of the three preparations: purified feline immunodeficiency virus (fiv) incorporated into immune stimulating complexes (iscoms), recombinant fiv p24 iscoms, or a fixed, inactivated cell vaccine in quil a. cats inoculated with the fiv iscoms or the recombinant p24 iscoms developed high titres of antibodies against the core protein p24 but had no detectable antibodies against the env protein gp120 or virus neutralising antibodies. in contrast, all of the cats inoculat ... | 1992 | 1337397 |
| retrovirus infections in non-domestic felids: serological studies and attempts to isolate a lentivirus. | an african lioness from the zoo of zurich had to be euthanized because of an inoperable tumor. the serum tested negative for feline leukemia virus (felv) p27 antigen by enzyme-linked immunosorbent assay (elisa) but was strongly positive for feline immunodeficiency virus (fiv) antibodies by elisa and western blot. when her only offspring and mate were tested for fiv, high antibody titers to fiv were also found in their serum. lymphocytes were prepared from these two lions on different occasions a ... | 1992 | 1337398 |
| feline immunodeficiency virus neurotropism: evidence that astrocytes and microglia are the primary target cells. | to investigate the neuropathogenesis of feline immunodeficiency virus (fiv) infection in vitro, we have utilized three populations of cultured feline neural cells (astrocytes, microglia, brain endothelium) to assess the relative susceptibility to fiv infection, ability to produce viral antigens, and effects of infection on cell survival. astrocytes appeared to be the most susceptible to infection, followed by microglia, whereas brain endothelial cells were relatively resistant to infection. astr ... | 1992 | 1337399 |
| clinical and pathological findings in feline immunodeficiency virus experimental infection. | a study is described of the clinical and pathological findings in 20 specific pathogen free cats infected when 1 year old with feline immunodeficiency virus and monitored over 12 months. cats were divided into two groups (a and b). the clinical and clinicopathological features were studied in group a. in group b, at 1, 2, 4, 9 and 12 months post infection two cats were necropsied. clinically all cats developed generalised lymphadenopathy, six cats were neutropenic and five cats lymphopenic. thre ... | 1992 | 1337400 |
| detection of feline immunodeficiency virus infection in bone marrow of cats. | natural or experimental feline immunodeficiency virus (fiv) infection in cats is often associated with hematologic abnormalities which are similar to those observed in human immunodeficiency virus (hiv) infected patients. to determine if cells in bone marrow are infected with fiv and whether severity of hematopoietic disorder is correlated with the level of viral infection, bone marrow tissues from ten experimentally and two naturally fiv infected cats were examined by in situ hybridization for ... | 1992 | 1337401 |
| decreased mitogen responsiveness and elevated tumor necrosis factor production in cats shortly after feline immunodeficiency virus infection. | we present the results of an investigation into the effects of feline immunodeficiency virus (fiv) infection on the response to mitogens and cytokine production in the first month of infection. we were able to demonstrate a depression of response of peripheral blood mononuclear cells to the mitogens concanavalin a, phytohaemagglutinin and pokeweed mitogen, with the response to pokeweed mitogen being most severely affected. the response of the cells of the spleen were affected by 10 days post inf ... | 1992 | 1337402 |
| tumor necrosis factor alpha levels in cats experimentally infected with feline immunodeficiency virus: effects of immunization and feline leukemia virus infection. | tumor necrosis factor alpha (tnf alpha) levels were determined by enzyme-linked immunosorbent assay (elisa) and by cell culture bioassay in supernatants of lipopolysaccharide-stimulated feline monocyte cultures and in cat serum samples. there was a good correlation between the results obtained by the two methods. from the fact that tnf alpha was neutralized quantitatively by antibodies to human tnf alpha in feline monocyte supernatants and in feline sera, it was concluded that feline tnf alpha i ... | 1992 | 1337403 |
| transmission of feline immunodeficiency virus from infected queens to kittens. | this study demonstrates the transmission of feline immunodeficiency virus (fiv) from infected queens to kittens in two separate litters. queen 1 was infected by intravenous administration of fiv at 22 days prior to parturition. two out of three kittens from the litter were found to be viremic at 10 weeks of age as detected by culture isolation and polymerase chain reaction detection of fiv dna in peripheral blood mononuclear leukocytes. the third kitten remained aviremic through 40 weeks of age. ... | 1992 | 1337404 |
| incidence of feline immunodeficiency virus reactive antibodies in free-ranging lions of the kruger national park and the etosha national park in southern africa detected by recombinant fiv p24 antigen. | lion sera from the kruger national park (knp) dating back to 1977 and from the etosha national park (enp), obtained from 1989 to 1991, have been analysed by elisa and western blot analyses using a genetically engineered antigen representing the p24 structural protein of feline immunodeficiency virus (fiv). it was concluded that some 83% of 98 knp lion sera reacted with the p24 antigen, while none of 28 enp lion sera reacted. a few other knp felids (cheetahs and genets) gave samples that did not ... | 1992 | 1338477 |
| diseases of the european wildcat (felis silvestris schreber, 1777) in great britain. | the author describes an examination conducted in collaboration with the nature conservancy council of great britain into the status with regard to disease, conservation and genetics of the european wildcat (felis silvestris). feline leukaemia virus (felv) infection was detected by positive enzyme-linked immunosorbent assay in blood from 2 of 23 wildcats and was tested and confirmed by felv isolation in one of the two cats. this is the first time the virus has been clearly demonstrated in a free- ... | 1992 | 1339067 |
| immunological changes in cats with concurrent toxoplasma gondii and feline immunodeficiency virus infections. | to examine the immunological changes in cats concurrently infected with feline immunodeficiency virus (fiv) and toxoplasma gondii, kittens (four per group) were inoculated with fiv, t. gondii, both agents, or no pathogens. blood mononuclear cells and plasma were collected weekly for lymphocyte assays and serology. at week 14, spleen and lymph node cells were used for lymphocyte assays; brains and mesenteric lymph nodes were used for isolation of t. gondii. more t. gondii organisms were present i ... | 1992 | 1346403 |
| feline immunodeficiency virus. proceedings of an international conference. davis, california, 4-7 september 1991. | | 1992 | 1363006 |
| effect of primary phase feline immunodeficiency virus infection on cats with chronic toxoplasmosis. | the effect of primary phase feline immunodeficiency virus (fiv) infection on clinical signs, hematological values, toxoplasma gondii oocyst shedding, t. gondii-specific serology, t. gondii-specific cell-mediated immune responses, non-specific cell-mediated immune responses, and lymphocyte subpopulations from cats with experimentally induced chronic toxoplasmosis was studied. no significant clinical or hematologic abnormalities were noted following inoculation with fiv. t. gondii-specific igm was ... | 1992 | 1363007 |
| use of two virustatica (azt, pmea) in the treatment of fiv and of felv seropositive cats with clinical symptoms. | in the present study the therapeutic efficacy and the side effects of two antiretroviral compounds used in human acquired immunodeficiency syndrome (aids) research, 3'-azido-2',3'-dideoxythymidine (azt, zidovudine, retrovir) and 9-(2-phosphonylmethoxyethyl)adenine (pmea), were investigated in the treatment of cats naturally infected with feline immunodeficiency virus (fiv) and cats naturally infected with feline leukemia virus (felv). azt was administered subcutaneously at a dose of 5 mg kg-1 bo ... | 1992 | 1363008 |
| immunization-induced decrease of the cd4+:cd8+ ratio in cats experimentally infected with feline immunodeficiency virus. | in a previous experiment a group of 15 specified pathogen free (spf) cats were experimentally infected with a swiss isolate of feline immunodeficiency virus (fiv). a group of 15 spf cats served as fiv negative controls. nine cats of each group were vaccinated with a recombinant feline leukemia virus (felv) vaccine, six cats in each group with a placebo vaccine. all vaccinated cats developed high antibody titers to felv and were protected against subsequent felv challenge infection. in both contr ... | 1992 | 1363009 |
| persistent upregulation of mhc class ii antigen expression on t-lymphocytes from cats experimentally infected with feline immunodeficiency virus. | a significant elevation in the percentage of cd4+ and cd8+ t-lymphocytes expressing major histocompatibility complex (mhc) class ii antigens was observed in the blood of cats shortly after they were experimentally infected with feline immunodeficiency virus (fiv). in addition to an increase in the relative proportion of t-lymphocytes expressing class ii antigens, there was an increase in the density of class ii antigens on the cell surface. these elevations were still evident at the completion o ... | 1992 | 1363010 |
| interaction of acute feline herpesvirus-1 and chronic feline immunodeficiency virus infections in experimentally infected specific pathogen free cats. | cats with or without chronic feline immunodeficiency virus (fiv) infection were exposed to feline herpesvirus, type 1 (fhv-1). fiv infected cats became sicker than non-fiv infected cats and required more supportive treatment. however, there were no differences in the length of their illness or in the levels and duration of fhv-1 shedding. fhv-1 infection caused a transient neutrophilia at day 7 with a rapid return to preinfection levels. the neutrophilia coincided with a transient lymphopenia th ... | 1992 | 1363011 |
| impaired t-cell priming and proliferation in cats infected with feline immunodeficiency virus. | cats naturally infected with feline immunodeficiency virus (fiv) are particularly susceptible to infection with opportunistic pathogens, suggesting that these animals are unable to develop an effective immune response against the pathogen. previous studies have used cd4+:cd8+ lymphocyte ratios and mitogen blastogenesis to identify immunological abnormalities in fiv-infected cats. however, these studies provide limited information for understanding the nature of the cellular dysfunction in fiv-in ... | 1992 | 1348945 |
| association between feline immunodeficiency virus antibodies and host characteristics in finnish cats. | toward the end of 1989 the largest private veterinary laboratory in finland (vet/lab) began using a commercial combined elisa test for feline immunodeficiency virus (fiv) antibodies and feline leukemia virus (felv) antigens (cite combo). the overall proportion of fiv seropositive feline samples was 5% during the 22 month study period. the number of tests performed increased slowly while the positive test results decreased with time (7% in 1990 and 4% in 1991). the decrease in prevalence was assu ... | 1992 | 1336930 |
| rnase h activity associated with reverse transcriptase from feline immunodeficiency virus. | reverse transcription of retroviral genomes requires the action of an rnase h for template switching and primer generation. in this report, we compare enzymatic properties of the rnase h associated with the reverse transcriptase (rt) from feline immunodeficiency virus (fiv) and that from human immunodeficiency virus (hiv). both enzymes displayed substrate preference for poly[3h](rg) . poly(dc) hybird over poly[3h](ra) . poly(dt) and cation preference for mg2+ over mn2+. activity of the fiv rnase ... | 1992 | 1370549 |
| altered cell tropism and cytopathicity of feline immunodeficiency viruses in two different feline cd4-positive, cd8-negative cell lines. | two interleukin-2-dependent feline cd4-positive and cd8-negative cell lines, mya-1 and the newly established fel-039, were used as host cells for infection with feline immunodeficiency virus (fiv). all fiv strains used, the petaluma strain and several new isolates, were highly cytopathic to mya-1. in contrast, the kinetics of fiv replication in fel-039 differed greatly depending on the strain tested, i.e., noninfectious strain, highly cytopathic strain, and less cytopathic strain producing a per ... | 1992 | 1374812 |
| localisation of three epitopes of the env protein of feline immunodeficiency virus. | the envelope protein of the feline immunodeficiency virus (fiv) was analyzed using several epitope prediction programs based on profiles of hydrophilicity, antigenicity, and probability of residues to lie on the protein surface. tentative homologies with the immunodominant epitope sites in simian virus (siv) or human immunodeficiency virus (hiv) such as the v3 loop, the site of cleavage between surface envelope protein (su) and transmembrane envelope protein (tm), and sites of n-glycosylation we ... | 1992 | 1374840 |
| in vitro properties and experimental pathogenic effect of three strains of feline immunodeficiency viruses (fiv) isolated from cats with terminal disease. | three strains of virus isolated from peripheral blood mononuclear cells (pbmc) of sick cats were identified as feline immunodeficiency virus (fiv) on the basis of in vitro cytopathic effect, t-lymphotropism, ultrastructural morphology and magnesium-dependent reverse-transcriptase activity. the pathogenic properties of two isolates were studied in 13 experimentally infected cats. the primary phase of infection was characterised by a range of haematological (neutropenia, lymphopenia, presence of a ... | 1992 | 1377438 |
| immunologic responses in healthy random-source cats fed n,n-dimethylglycine-supplemented diets. | the immunomodulatory capacities of n,n-dimethylglycine (dmg) were examined in random-source cats. blood mononuclear leukocytes of healthy adult cats that had negative results to tests for felv and feline immunodeficiency virus were exposed in vitro to various concentrations of dmg (10 to 1,000 micrograms/ml) and were evaluated for proliferative responses to t- or b-cell phytomitogens. although increased, mean lymphocyte blastogenic responses to phytolectins in dmg-treated cultures did not differ ... | 1992 | 1381880 |
| worldwide prevalence of lentivirus infection in wild feline species: epidemiologic and phylogenetic aspects. | the natural occurrence of lentiviruses closely related to feline immunodeficiency virus (fiv) in nondomestic felid species is shown here to be worldwide. cross-reactive antibodies to fiv were common in several free-ranging populations of large cats, including east african lions and cheetahs of the serengeti ecosystem and in puma (also called cougar or mountain lion) populations throughout north america. infectious puma lentivirus (plv) was isolated from several florida panthers, a severely endan ... | 1992 | 1382145 |
| identification of a feline immunodeficiency virus gene which is essential for cell-free virus infectivity. | feline immunodeficiency virus (fiv) contains at least three small open reading frames (orfs) in the genome, in addition to the three structural genes. two of these orfs (putative vif and orf-a) have unknown functions. northern (rna) blot analysis of mrnas from an fiv-infected cell line showed that the putative-vif-specific mrna was expressed as a 5.2-kb species. to examine the function of the putative vif gene, we constructed mutants carrying a deletion in either the vif-like gene or the rev gen ... | 1992 | 1382146 |
| highly conserved epitope domain in major core protein p24 is structurally similar among human, simian and feline immunodeficiency viruses. | linear b cell epitopes were mapped on the major core protein p24 of human immunodeficiency virus type 1 (hiv-1), simian immunodeficiency virus (sivagm) and feline immunodeficiency virus (fiv) using a fusion protein-based method and murine monoclonal antibodies reactive against the p24 antigens expressed on the surface of hiv-1- and fiv-infected cells. the results suggest that the sites identified here are encoded at similar positions in the three virus genomes and consist of highly conserved epi ... | 1992 | 1383411 |
| inhibition of reverse transcriptase from feline immunodeficiency virus by analogs of 2'-deoxyadenosine-5'-triphosphate. | the replication of feline immunodeficiency virus (fiv) in cultured cells was inhibited by 2',3'-dideoxyadenosine (dda) and by 9-(2-phosphonylmethoxyethyl)adenine (pmea) with ic50 values of 0.98 and 0.95 microm, respectively. the effects of the presumed active forms of these inhibitors, ddatp and pmea-diphosphate (pmeapp), upon the fiv reverse transcriptase (rt) were examined with two different template-primer systems. both of these compounds were potent inhibitors of the fiv rt in reactions with ... | 1992 | 1384501 |
| pharmacokinetics of potential anti-aids agents thiofoscarnet and foscarnet in the cat. | the pharmacokinetics of thiophosphonoformate (tpfa) and phosphonoformate (foscarnet, pfa) were studied in normal adult cats, a species susceptible to feline immunodeficiency virus (fiv) infection. parent drugs and metabolites were quantitated by high-performance liquid chromatography (hplc). tpfa had a mean terminal plasma half-life of 42 min, a total clearance of 4.58 ml/min/kg, and a renal clearance of 1.24 ml/min/kg (n = 4). tpfa underwent in vivo metabolism to pfa and thiophosphonic acid (tp ... | 1992 | 1387417 |
| treatment of mandibular squamous cell carcinoma in cats by use of mandibulectomy and radiotherapy: seven cases (1987-1989). | seven cats with squamous cell carcinoma involving the mandible were treated by surgery and radiotherapy. surgery consisted of hemimandibulectomy or combined rostral and hemimandibulectomy, gastrostomy tube placement, and submandibular lymph node excisional biopsy. radiotherapy (orthovoltage or 60co) commenced 2 weeks after surgery. histologically, the tumor invaded surgical margins in 6 of 7 cats. nerve infiltration was histologically identified in 2 cats. all cats had stage-3 disease with radio ... | 1992 | 1399785 |
| characterization of morphologic changes and lymphocyte subset distribution in lymph nodes from cats with naturally acquired feline immunodeficiency virus infection. | lymph nodes were collected at biopsy or necropsy from 18 cats with naturally acquired symptomatic feline immunodeficiency virus (fiv) infection and from 18 seronegative cats. thirty-five of the cats were domestic shorthairs and one was a persian cross. the cats ranged from 7 months to 16 years of age and were mainly obtained from california veterinary practitioners, a california cattery, and a veterinary teaching hospital. based on clinical signs present at tissue collection, ten fiv-infected ca ... | 1992 | 1413406 |
| enzyme-linked immunosorbent assays for the detection of toxoplasma gondii-specific antibodies and antigens in the aqueous humor of cats. | serum and aqueous humor samples, collected from 14 clinically normal cats and 96 cats with clinical evidence of intraocular inflammation, were assayed with elisa for toxoplasma gondii-specific immunoglobulin m (igm), t gondii-specific igg, t gondii-specific antigens, total igg, and total igm. additionally, serum was assayed with elisa for feline leukemia virus p27 antigen and antibodies against the feline immunodeficiency virus as well as with an immunofluorescent antibody assay for antibodies a ... | 1992 | 1429123 |
| elevation of feline interleukin 6-like activity in feline immunodeficiency virus infection. | the involvement of feline interleukin 6 (il-6)-like activity in polyclonal b-cell activation in feline immunodeficiency virus (fiv) infection was investigated by using the proliferative response of hybridoma cell clone b3b1. cats spontaneously infected with fiv had hyperimmunoglobulinemia, as shown by increases in the percentage of gamma-globulin and the plasma igg concentration and decrease in the albumin/globulin (a/g) ratio. because il-6 plays an essential role in the differentiation of activ ... | 1992 | 1451326 |
| an early defect in primary and secondary t cell responses in asymptomatic cats during acute feline immunodeficiency virus (fiv) infection. | as in hiv infection of humans, cats infected with fiv are particularly susceptible to secondary infection by opportunistic pathogens, suggesting an impaired ability to elicit an effective immune response against foreign antigens. in order to investigate the development of immunity in fiv-infected cats, we have used an autologous culture system to directly measure priming of naive cd4+ t cells to soluble protein antigen, in vitro. using this assay, we showed previously that cats infected with fiv ... | 1992 | 1458687 |
| siv and fiv vaccine studies at uc davis: 1991 update. | | 1992 | 1334682 |
| animal cell culture and the aids problem. | | 1990 | 1369270 |
| use of hollow fiber technology for large scale production of viruses and viral antigens. | | 1990 | 1369281 |
| evaluation of feline immunodeficiency virus and feline leukemia virus transmembrane peptides for serological diagnosis. | the general model for retrovirus transmembrane (tm) proteins proposed by gallaher et al. (w. r. gallaher, j. m. ball, r. f. garry, m. c. griffin, and r. c. montelaro, aids res. hum. retroviruses 5:431-440, 1989) suggests that all retrovirus tm proteins may contain an immunodominant domain (imd-tm peptide) located at the apex of the tm polypeptide. although this imd-tm peptide has been shown to be immunodominant in a variety of lentivirus infections, there has not been a detailed serological anal ... | 1992 | 1629349 |
| naturally occurring animal models of the acquired immune deficiency syndrome (aids). | | 1991 | 1645558 |
| analyses of the requirements for the synthesis of virus-like particles by feline immunodeficiency virus gag using baculovirus vectors. | feline immunodeficiency virus (fiv) gag gene was expressed in baculovirus vectors to investigate its potential for the assembly of virus-like particles. the unprocessed 50-kda fiv gag precursor made in infected insect cells by recombinant acfivgag-1 was myristoylated, assembled at the cell surface into virus-like particles (with diameters of approximately 100 nm), and efficiently released into the culture supernatant fluids. the presence of the complete viral-coded protease component of the fiv ... | 1991 | 1647071 |
| transmission of feline immunodeficiency virus from mother to kitten. | | 1991 | 1648280 |
| prevention of retrovirus infection after injury with contaminated instruments: an experimental study. | owing to similarities between human immunodeficiency virus and feline retroviruses, the feline model was chosen for the study to investigate the efficacy of timely topical treatment of accidental human immunodeficiency virus infection in the operating room. cats were subcutaneously inoculated with either feline leukemia virus or feline immunodeficiency virus. an effort was made to neutralize the virus in loco either by infiltration of the inoculation site with povidone-iodine or with monoclonal ... | 1991 | 1648894 |
| identification of feline immunodeficiency virus rev gene activity. | we constructed 16 deletion mutants from an infectious molecular clone of feline immunodeficiency virus (fiv) and a reporter plasmid carrying the bacterial chloramphenicol acetyltransferase (cat) gene to identify the rev transactivator activity of the virus. cotransfections of various mutants and the rev reporter clone bearing a portion of fiv env in addition to the cat gene revealed that the sequence important for the augmentation of cat production was located in three separate parts of the viru ... | 1991 | 1649349 |
| isolation in italy of feline immunodeficiency virus (fiv). | the authors report the isolation in italy of feline immunodeficiency virus (fiv) from a cat inoculated with whole blood from a naturally fiv infected cat. the virus was isolated in feline circulating leucocytes cultured in rpmi medium and stimulated with concanavalin-a and recombinant human interleukin-2. the infected cultures showed a characteristic cytopathic effect (ballooning degeneration, giant cell formation, cell death) and a specific fuorescence using fiv-positive cat serum and monoclona ... | 1991 | 1649960 |
| humoral immune response to t cell dependent and independent antigens in cats infected with feline immunodeficiency virus. | | 1991 | 1650604 |
| activation of feline immunodeficiency virus long terminal repeat by feline herpesvirus type 1. | by transfection of a recombinant plasmid containing the feline immunodeficiency virus (fiv) long terminal repeat (ltr) linked to the chloramphenicol acetyltransferase (cat) gene followed by infection of feline herpesvirus type 1 (fhv-1) into crandell feline kidney cells and felis catus whole fetus 4 cells, enhancement of cat activity was demonstrated. furthermore, individual feline t-lymphocytes were productively co-infected with both fiv and fhv-1 in vitro as determined by two-color immunofluor ... | 1991 | 1651603 |