Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| biochemical properties of a hamster syncytium-forming ("foamy") virus. | a hamster syncytium-forming ("foamy") virus (hfv) was characterized. the hfv sedimented in isopyknic sucrose density gradients at 1.16-1.165 g/ml. it had rna but no dna, its replication was inhibited by actinomycin d, and it contained virion-associated, rna-dependent dna polymerase. analysis of the rna from purified virus showed several species: 62s, 40s, 28-30s, 18-20s, and 4-7s. | 1975 | 47398 |
| the foamy viruses. | 1975 | 51620 | |
| [induction, by 5-bromo-2'-deoxyuridine, of a "foamy" virus previously undetected in hamster cells transformed by sv40]. | tsv5 clone 2 cells in normal conditions of culture contain only an expressed rna virus (r-type virus). however, exposure of the cells to 5-bromo-2'-deoxyuridine with dexamethasone, induced synthesis of a syncitium-forming ("foamy") virus. in other hamster cell lines, the same treatment fails to induce a "foamy" virus. the origin of this "foamy" virus is discussed. | 1975 | 55314 |
| isolation of foamy viruses from baboon (papio cynocephalus) tissues. | fourty per cent of baboon kidney cell cultures were found to contain foamy virus contaminants regardless of sex of the animal, source or time of year. the older the animal, however, the higher the incidence. fifty percent of placentas examined contained foamy virus, with first and second trimester specimens more likely to be positive. foamy virus isolates from baboon lymphocytes were also more frequent as the age of the animal increased. freezing and thawing these lymphocytes prevented foamy vir ... | 1975 | 168767 |
| pathogenesis of simian foamy virus infection in natural and experimental hosts. | inoculation of simian foamy virus type 1 into new zealand white rabits resulted in an infection which was very similar to that observed in naturally infected nonhuman primates. both intraperitoneal and intranasal inculations were found to be efficient procedures for the establishment of the infection in rabbits. infection by the nasal route was found to be the best method, whereas no infection could be established by feeding virus in the drinking water. once infection was established, virus pers ... | 1975 | 170201 |
| isolation of foamy virus from rhesus, african green and cynomolgus monkey leukocytes. | foamy virus (fv) was recovered regularly from the leukocyte of rhesus and cynomolgus monkeys and somewhat less often from african green monkey leukocytes. virus was found in virtually all organs of experimentally infected rhesus monkeys. no illness or pathologic abnormalities were noted in these animals or in any of the naturally infected animals in spite of the prolonged period of viral persistence in various organs and tissues. | 1975 | 171409 |
| viral spread in the presence of neutralizing antibody: mechanisms of persistence in foamy virus infection. | several viruses were categorized on the basis of their ability to spread from cell to contiguous cell and form plaques in the presence of antiviral antibody. herpes simplex virus, cytomegalovirus, and vaccinia, measles, and foamy viruses were able to spread in the presence of neutralizing antibody, whereas coxsackievirus, encephalomyocarditis virus, vesicular stomatitis virus, mumps virus, and simian virus 5 failed to spread. a detailed study of one of these virus groups (simian foamy viruses) s ... | 1976 | 185150 |
| isolation and characterization of lymphocyte associated foamy virus from a red uakari monkey (cacajao rubicundus). | a syncytium-forming virus was isolated from the lymphocytes of a uakari monkey 70 days after establishing a lymphocyte/owl monkey kidney coculture in the wild. the morphology and morphogenesis of the virus, plus its physicochemical characteristics indicate that the agent is a foamy virus. an unusal cell alteration found in cultures infected with this foamy was the formation of eosinophilic intracytoplasmic inclusion in association with the syncytia. the agent was found to be antigenically distin ... | 1976 | 191616 |
| virological studies of baboon (papio hamadryas) lymphoma: isolation and characterization of foamyviruses. | in accordance with a memorandum of understanding in cancer research between scientists in the ussr and the usa, virological studies were performed on two baboons from the russian colony at the institute of experimental pathology and therapy at sukhumi where several cases of leukemia have been observed over the past few years. foamyvirus isolations were made from lymphoid cells of both of these monkeys, one of which had a confirmed case of lymphoma. the isolates were similar to each other serolog ... | 1976 | 58063 |
| establishment of cell substrates for nonhuman primates. | 1976 | 201524 | |
| enhancement of ige-mediated histamine release from human basophils by viruses: role of interferon. | human leukocytes maintained in culture are induced to release histamine when exposed to ragweed antigen e or anti-ige. leukocyte cultures incubated with virus (i.e. hsv-1, influenza a, and adeno-1) but not exposed to ragweed antigen e or anti-ige fail to release histamine. if, however, leukocyte cultures are first exposed to virus and then to ragweed antigen e or anti-ige, significant enhancement of histamine release occurs. both infectious and inactivated virus enhance histamine release and the ... | 1977 | 67173 |
| reverse transcriptase of foamy virus. purification of the enzymes and immunological identification. | reverse transcriptase from foamy virus, strain h4188 was estimated and purified. the enzyme has the following characteristics: 1. the reaction utilized preferentially oligo (dt) poly (ra) as a primer-template; however, the synthetic primer-template oligo (dt) poly (da) could also be used to some extent. 2. the reaction utilized oligo (dg) poly (rc) as a primer-template with very low efficiency. 3. the crude virus preparation had a detectable endogenous reaction using the four deoxyribonucleotide ... | 1977 | 74244 |
| further biological properties of the human syncytial virus. | some biological properties of the human syncytial virus have been examined. a 13-day plaque assay in whole human embryo fibroblasts (hef) has been developed using a liquid (growth medium) overlay. the plaques were 0.7-2 mm in diameter and often showed a clear central zone with irregular edges. pretreatment of hef monolayers with the polycation deae-dextran for either 30 min or 1 h was found to enhance plaque formation by a factor of from 2- to 7-fold. the plaque assay procedure required cell cul ... | 1977 | 194865 |
| infectious dna from cells infected with feline syncytium-forming virus (spumavirinae). | dna isolated from cells infected with fsfv (a foamy virus) is infectious when tested on susceptible cells. the virus produced by this infectious dna is identical to the original infecting virus in terms of plaque and virion morphology and serology. | 1977 | 199699 |
| pelvic endometriosis and simian foamy virus infection in a pigtailed macaque. | pelvic endometriosis and simian foamy virus infection occurred in a pigtailed macaque. diffuse omental, peritoneal, and intestinal implantation of endometrium resulted in massive adhesions between adjacent abdominal and pelvic viscera, with formation of a large mass in the right caudal quadrant of the abdomen. simian foamy virus type 1 was isolated from ectopic endometrium and from the uterine wall but was considered to be merely epiphenomenal. | 1977 | 200594 |
| a haemagglutination assay for the primate syncytium-forming (foamy) viruses. | preparations of highly concentrated simian foamy virus type 1 (sfv1)agglutinate guinea pig red blood cells. the agglutination occurs both at 22 degrees and 37 degrees c. it is inhibited by specific antisera against sfv1 but also by antisera prepared against several other types of simian foamy viruses. | 1977 | 188979 |
| possible role of infectious simian foamy virus dna in persistent infection. | simian foamy virus type 7 (sfv-7) can persist in peripheral blood leukocytes of sfv-7-infected rabbits. rabbit peripheral blood leukoyctes cultured in vitro did not support the growth of sfv-7, but low titer of virus could be detected after 4 to 5 days incubation. the dna derived from sfv-7 infected primary rabbit kidney cells is infectious. the presence of sfv-7 dna provirus in infected rabbit kidney cells during replication may contribute one of the mechanisms of persistance. | 1977 | 211013 |
| antigenic relationship of human foamy virus to the simian foamy viruses. | a foamy virus isolated by achong et al. from a human nasopharyngeal carcinoma was studied to determine its antigenic relationship to the eight known simiam foamy viruses (sfv). using reciprocal cross-immunofluorescent and cross-neutralization techniques, we found the human isolate to be closely related to sfv type 6. in a seroepidemiological survey, neutralizing antibody to the human foamy virus was not detected in the sera of animal caretakers or laboratory personnel who routinely handled a wid ... | 1978 | 78897 |
| isolation of foamy virus from patient with dialysis encephalopathy. | 1978 | 80725 | |
| some infectious diseases of wild vervet monkeys (cercopithecus aethiops pygerythrus) in south africa. | our surveys indicate that nearly all batches of vervet monkeys arriving at the national institute for virology from various areas of south africa, are infected with foamy viruses and there is evidence that intra-urterine infection also occurs. monkeys from certain areas of south africa are apparently infected with the protozoal parasite entopolypoides macaci in a sub-clinical state which becomes active when the monkeys are splenectomised. serological studies indicate that infections with schisto ... | 1978 | 218005 |
| human foamy virus: further characterization, seroepidemiology, and relationship to chimpanzee foamy viruses. | a foamy virus present in human nasopharyngeal carcinoma tissue was studied for a number of biological properties, including range of cellular susceptibility, growth curve, evolution of cytopathic effect in relation to cellular fusion and intracellular viral distribution, reverse transcriptase activity, and buoyant density. the virus was also studied immunologically and found to be closely related to the chimpanzee foamy viruses, particularly simian foamy virus type 6, with which it shares common ... | 1978 | 206631 |
| [foamy viruses in baboons and macaques]. | the occurrence of foamy viruses among baboons and macaca monkeys in sukhumi monkey farm was investigate;. the monkeys were shown to be carriers mainly of foamy virus type ii. the frequency of virus isolation increased with the age of the animals and reached 88.8-100% in adult specimens. the virus behaviour in cell cultures is described. the morphological characteristics of the virus are based on electron microscopic examinations of ultrathin sections of primary and inoculated cell cultures. | 1978 | 208305 |
| [isolation of foamy virus type ii out of haematopoetic cells from baboons with haematoblastoses and from healthy animals (author's transl)]. | foamy virus type ii persists in the haematopoetic organs of 75 percent of baboons in the suchumi flock. a mixed infection with foamy virus types i and ii seems to be possible. foamy viruses are isolated as well from monkeys with haemoblastoses as from healthy animals. new information concerning the intrauterine transmission of foamy viruses were obtained. | 1978 | 210734 |
| feline syncytium-forming virus: dna provirus size and structure. | an infectious dna assay has been used to investigate the size and structure of the genome of feline syncytium-forming virus (fsfv). the dose response between dna extracted from fsfv-infected cells and plaque number on feline embryo cells followed two-hit kinetics and the mol. wt. of the proviral dna was estimated as approx. 6 x 10(6). | 1979 | 227986 |
| comparison of the antigens produced by foamy virus in a cytolytic and a persistent infection of hep2 cells. | the antigens from cytolytic infections of hep2 cells by type i simian foamy virus produced two multicomponent precipitation lines when tested by immunodiffusion with the homologous hyperimmune rabbit antiserum. the antigens obtained from a non-productive infection of mk5 virus in hep2 cells produced only those precipitation lines which corresponded with the inner lines obtained from the cytolytic infection. similarly, hyperimmune rabbit antiserum against antigens extracted from the persistent in ... | 1979 | 227994 |
| simian foamy virus-induced immunosuppression in rabbits. | 1979 | 230289 | |
| isolation and characterization of a new simian foamy virus serotype from lymphocytes of a papio cynocephalus baboon. | a new type of syncytium-forming (foamy) virus was isolated from peripheral lymphocytes of a papio cynocephalus baboon after cocultivation with a rhesus monkey cell line. the isolate was characterized by cytopathogenic effect, host range, electron microscopy, reverse transcriptase activity and physical and chemical properties. seroneutralization tests indicate that the new isolate is antigenically distinct from the other nine known simian foamy virus serotypes. | 1979 | 231658 |
| factors affecting the growth and titration by immunofluorescence of simian foamy virus. | this paper presents some observations concerned with the growth of simian foamy virus and some modifications which should be introduced to the fluorescence assay of foamy virus. the modified procedure is the most sensitive method described for the titration of foamy virus. examination of the optimal conditions for the growth and titration by fluorescence assay of simian foamy virus showed that the virus was particularly sensitive to changes in virus and cell concentration. at the low cell concen ... | 1979 | 231947 |
| isolation of foamy virus from patients with de quervain thyroiditis. | 1979 | 89378 | |
| attempt to isolate infectious agent from bone-marrow of patients with multiple sclerosis. | 1979 | 89467 | |
| feline syncytium-forming virus: identification of a virion associated reverse transcriptase and electron microscopical observations of infected cells. | the maturation of feline syncytium-forming virus (fsfv), a member of the foamy virus sub-family (spumavirinae), has been studied by electron microscopy of thin sections of infected feline embryo (fea) cells. the initial event observed was formation of crescent-shaped nucleoids at the plasma membrane. as budding progressed, the nucleoid became circular in outline with an electron-lucent centre in fully mature extracellular particles. these observations suggested that the maturation of fsfv in ful ... | 1979 | 90117 |
| antibody responses to herpesvirus papio antigens in baboons with lymphoma. | an epstein-barr virus-related herpesvirus, termed herpesvirus papio (hvp), was isolated from baboons (papio hamadryas) at the institute of experimental pathology and therapy, sukhumi, ussr, where there is a continuing outbreak of lymphoma. in the present study sera from diseased baboons and from age- and sex-matched control animals were examined for antibodies to hvp antigens. results showed that animals with lymphoid disease had antibodies to hvp virus capsid, early, soluble, and nuclear antige ... | 1979 | 216640 |
| the prevalence of naturally occurring antibodies to human syncytial virus in east african populations. | a seroepidemiological study of naturally occurring antibodies to the human syncytial virus has been carried out by means of an indirect immunofluorescence test on 639 east africans, consisting of 493 normal ugandans, 66 kenyan patients with nasopharyngeal carcinoma (npc), and 80 kenyan and tanzanian patients with various other tumours or non-cancerous conditions. it was found that 3.4% of the normal individuals had antibodies to the virus and serial serum samples were available from 14 of these, ... | 1980 | 6245177 |
| seroepidemiology of human syncytial virus: antibody prevalence in the pacific. | a seroepidemiological survey of the human syncytial (foamy) virus was done by means of an indirect immunofluorescence test on 1,717 sera from nine different pacific island territories. the specificity of the reaction was verified by neutralization tests. the study indicated that the virus is ubiquitous in this part of the world, with no region being entirely free of antibody. the antibody prevalence ranged from a low of 1.2% in ponape to a high of 15.6% in the cook islands. the average prevalenc ... | 1980 | 6246030 |
| [spontaneous contamination of primary green monkey kidney cell cultures by foamy virus]. | examinations of 1653 batches of green monkey kidney cell cultures revealed contamination with foamy virus (fv) in 243 (16%) batches. from some of these cultures 65 strains of virus belonging to two serotypes were isolated. tests on sera from 1122 monkeys revealed antibody to fv in 985 (87.8%) animals. no correlation between the presence of antibody in the serum and virus recovery from monkey kidney cell cultures was observed, however. this might be due either to the lack of the virus in the kidn ... | 1980 | 6254265 |
| replication of human syncytium-forming virus in human cells: effect of certain biological factors and selective chemicals. | the growth characteristics of the human syncytium-forming virus (hsfv) were examined in several human cell lines of normal and malignant origins and composing of either fibroblastic or epithelial-like cells. virus production occurred only in the fibroblastic diploid cell lines: hef (human embryonic cells, flow #5,000) and hfdl #645 (human fetal diploid lung), but not in the epithelial-like heteroploid cell lines: ra (a continuous line of human amnion), #999 (human bone marrow), and kb (carcinoma ... | 1981 | 6264025 |
| the rna of the human syncytium-forming (foamy) virus. | human syncytium-forming (foamy) virus was labeled with 3h-uridine and banded isopycnically in sucrose gradients (buoyant density = 1.16 to 1.18 g/cm3). viral rna extracted from the banded virus was analyzed either by rate zonal separation in sucrose gradients or by polyacrylamide-agarose gel electrophoresis. the results indicated that purified hsfv contains a 60s rna component plus several smaller molecular weight rna components. on dissociation with heat, smaller rna structures were released fr ... | 1981 | 6264892 |
| feline respiratory virus carriers in clinically healthy cats. | in two surveys, feline calicivirus was cultured from 19.7% and 15% of 66 and 201 clinically healthy cats respectively. feline viral rhinotracheitis virus was cultured also from 1.5% of oropharyngeal swabs collected in both surveys. feline syncytial virus was isolated from 5.5% oropharyngeal swabs collected in the second survey. the use of serological examination and corticosteroid treatment to stimulate virus shedding demonstrated that 25.8% cats in the first survey were carriers of feline viral ... | 1981 | 6266382 |
| biochemical characterization of simian foamy virus type i. | simian syncitium-forming ("foamy") virus type i (sfv1) was characterized biochemically. rna was extracted from purified virus either with 0.1 per cent sds or by the standard phenol-chloroform method. by both techniques a main component of 65-70s was found. denaturation of the 65-70s rna by heat resulted in a shift of the sedimentation coefficient mainly to a 30-35s component. electrophoresis on a composite polyacrylamide gel demonstrated the existence of three minor rna's: 8s, 5s and 4s respecti ... | 1981 | 6268018 |
| syncytium-forming virus of common marmosets (callithrix jacchus jacchus). | this communication describes the isolation and characterization of a new syncytium-forming virus of common marmosets (callithrix jacchus jacchus). the virus, isolated from skin explants and peripheral leukocytes of healthy animals, induced syncytia and subsequent cytolysis of several human, simian, and rodent fibroblastic cultures and induced a carrier state in mixed fibroblastic-epithelial or epithelial cell lines. cytoplasmic and nuclear viral antigen was demonstrated in infected cells by indi ... | 1981 | 6164648 |
| reverse transcriptase from simian foamy virus serotype 1: purification and characterization. | chromatography on heparin-sepharose, known for its affinity for nucleotide-binding polypeptides, was used to purify the viral rna-dependent dna polymerase (reverse transcriptase) from the core polypeptides of simian foamy virus type 1. this procedure allowed the recovery of highly purified enzyme with a high specific activity. the average molecular weight of this monomeric enzyme is 81,000 and is thus comparable to that found for other known primate retroviruses. reverse transcriptase activity o ... | 1982 | 6183451 |
| simian foamy virus pseudotypes of vesicular stomatitis virus: production and use in sero-epidemiological investigations. | simian foamy virus (sfv) pseudotypes of vesicular stomatitis virus have been successfully produced and their host range characterized. the availability of these pseudotypes has permitted the development of a rapid, quantitative assay to measure neutralizing antibody titres to sfv that has proved useful in a sero-epidemiological study. | 1982 | 6279771 |
| chemical inhibition of foamyvirus in primary baboon (papio cynocephalus) kidney cells. | this report describes the conditions for the use of aluminum chloride (alcl3) in growth and maintenance media for the suppression or inhibition of simian foamyviruses (sfv) in primary baboon kidney (bak) and rabbit kidney (rk) cell cultures. when rk cells were planted in medium containing alcl3, infected with sfv, and passaged, the growth of sfv was suppressed or inhibited by the presence of alcl3. with this method, bak cells yielded higher viral titers after infection with various viruses, thus ... | 1982 | 6286700 |
| [bovine syncytial virus--a review]. | 1983 | 6316867 | |
| characterization of rnase h activity associated with reverse transcriptase in simian foamy virus type 1. | spumavirinae or foamy viruses have been shown to have a characteristic rna-dependent dna polymerase activity. we demonstrate here the existence of an rnase h activity that copurifies with the 81-kilodalton monomeric polypeptide, which carries the rna-dependent dna polymerase activity of simian foamy virus type 1. rnase h degrades rna hybrid substrates; however, it does not solubilize single-stranded rnas. inactivation assays with heat, high levels of bivalent cations, ethidium bromide, and sodiu ... | 1983 | 6191042 |
| characterization of a foamy virus isolated from cercopithecus aethiops lymphoblastoid cells. | a virus derived from cells of a lymphoblastoid line originating from the lymph node of a healthy african green monkey was characterized as a typical member of the foamy virus subgroup of retroviridae by its morphological, physicochemical, biological and biochemical properties (reverse transcriptase activity). besides the usual host range of foamy viruses, the isolated strain revealed a remarkable t-lymphotropism, distinguishing it from the prototypes of foamy viruses previously isolated from afr ... | 1983 | 6193403 |
| isolations and serology of bovine spumavirus. | 1983 | 6615370 | |
| ultrastructural comparison of oncovirinae (type c), spumavirinae, and lentivirinae: three subfamilies of retroviridae found in farm animals. | the successive steps of maturation of seven retroviruses from five species of farm animals and one retrovirus from a mouse were compared in cell cultures. the viruses included three type c oncoviruses, one spumavirus, and three lentiviruses. although members of the 3 subfamilies shared some gross morphologic features such as budding on plasma membranes, core, and surface projections, differences were noted in the ultrastructural detail of these features. type c oncoviruses did not show any struc ... | 1984 | 6325793 |
| human spumavirus replication in human cells. | it was previously reported that the replication of the human syncytium-forming virus (hsfv), a spumavirus, occurred only in fibroblast-like cell lines (human fetal diploid lung #645 [hfdl]) but not in epithelial-like lines (recovered amnion) [ra]. factors that may be involved in such a phenomenon were the subject of this investigation. while both permissive (hfdl) and nonpermissive (ra) cell lines supported the replication of several representative animal viruses and adsorbed hsfv equally well, ... | 1984 | 6502141 |
| purification and characterization of the major envelope glycoprotein of simian foamy virus type 1. | simian foamy virus type 1 (sfv-1), the prototype of the spumavirinae, was subjected to disruption and serial purification procedures. separation of sfv-1 envelope components from viral cores was verified by electron microscopy, density gradient centrifugation and polyacrylamide gel electrophoresis. after affinity chromatography of the envelope polypeptides on a concanavalin a-sepharose column, a highly purified 70 000 mol. wt. protein was recovered. glycosylation of this gp70 was confirmed by gl ... | 1985 | 2410554 |
| isolation of a retrovirus and a herpesvirus from a captive california sea lion. | a non-oncogenic retrovirus was isolated from an explanted skin biopsy from a captive california sea lion (zalophus californianus) with a history of recurring skin lesions. the morphology of the viral particles in electron photomicrographs was characteristic of a foamy virus, a retrovirus in the subfamily spumavirinae. viral cytopathic effects consistent with foamy virus infection were observed in subsequent explants of skin and lymph nodes and co-cultivated peripheral blood leukocytes. the sea l ... | 1986 | 3012127 |
| detection and characterization of infectious dna intermediates of a primary foamy virus. | dna from human t-lymphoid (molt-4) and hamster kidney (bhk-21) cells infected with the t-lymphotropic simian foamy virus lk-3 was shown to be infectious, when assayed by transfection of bhk-21 cells. the proviral genome was further characterized by blot hybridization to a specific cdna probe, which had been prepared by reverse transcription in vitro using viral rna and rna-dependent dna polymerase present in cytoplasmic extracts of infected bhk-21 cells. this probe hybridized to a dna species of ... | 1986 | 3018132 |
| the multifaceted retrovirus. | i have attempted to illustrate the many different properties of retroviruses and their presence in a wide variety of animal species including humans. since the turn of this century, progress in the field of retrovirology has been noteworthy and many new and important scientific observations have been made (table 7). along the way, certain dogmas were replaced with new tenets. the recent recognition of retroviruses associated with human cancer and immunodeficiency places them into consideration a ... | 1986 | 3530440 |
| nucleotide sequence analysis of the env gene and its flanking regions of the human spumaretrovirus reveals two novel genes. | recombinant clones that represent the 3' part of the genome of the human spumaretrovirus (foamy virus) were established from viral dna and from dna complementary to viral rna. the recombinant clones were characterized by blot hybridizations and nucleotide sequence analysis. the deduced protein sequence of the clones at their 5' ends was found to be homologous to the 3' domain of retroviral reverse transcriptases. downstream of a small intergenic pol-env region a long open reading frame of 985 am ... | 1987 | 2820721 |
| characterization of a human lymphoblastoid cell line permanently modified by simian foamy virus type 10. | simian spumavirinae serotype, sfv10, of a papio cynocephalus baboon, was used to infect a human lymphoblastoid cell line, lv2. permanent growth and morphological alterations of infected cells occurred, even though no viral particles were detected. evidence for the presence of viral genomes in the modified cell line is provided indirectly from immunological studies and induction experiments followed by coculture procedures. the permanently modified cell line obtained (lv2-fb10) is an interesting ... | 1987 | 2826791 |
| molecular cloning of the genome of human spumaretrovirus. | dna of human spumaretrovirus (hsrv) was cloned from both cdna and from viral dna into phage lambda and bacterial plasmid vectors. the recombinant plasmids harboring viral dna were characterized by southern blot hybridization and restriction mapping. physical maps were constructed from cdna and found to be colinear with the restriction maps obtained from viral dna. the recombinant clones isolated contained viral dna inserts which range in size from 2.2 kb to 15.4 kb. the recombinant clones allowe ... | 1987 | 2830164 |
| simultaneous isolation of simian foamy virus and htlv-iii/lav from chimpanzee lymphocytes following htlv-iii or lav inoculation. | re-isolation of virus from htlv-iii b and lav-infected chimpanzee also yielded a simian foamy virus. this virus, replicated in htlv-iii b and lav-producing h 9 cells, had identical reverse transcriptase activity and caused similar cytopathic effects in h 9 cells. | 1987 | 2432853 |
| enhanced production of a human spumavirus (retroviridae) in semi-permissive cell cultures after treatment with 5-azacytidine. | infection by a human spumavirus of human foetal diploid lung (hfdl) cells was found to be productive with virus titres ranging from 10(3) to 10(5) p.f.u./ml. in contrast, infection of recovered amnion (ra) aneuploid cells resulted in a persistent infection with less than 100 p.f.u./ml infectious virus produced. the decreased sensitivity of ra cells to the spumavirus was not due to the failure of virus to penetrate into the cell since infectious virus was not produced even after transfection of i ... | 1987 | 2437243 |
| epidemiological studies of bovine spumavirus. | bovine spumavirus (bsv) infection is shown to be endemic in some herds in north queensland. the virus was readily isolated from leucocytes of the majority of mature cattle which were bsv antibody positive (bsv reactors) in the agar gel precipitin test (agpt). calves born to dams which were bsv reactors showed no bsv antibody or circulatory leucocyte-associated bsv (clab) at birth, but became bsv reactors following ingestion of colostrum, and maintained such evidence of passive immunity until 3-5 ... | 1988 | 2833003 |
| detection of immunological tolerance to bovine spumavirus (bsv) with evidence for salivary excretion and spread of bsv from the tolerant animal. | a group of 17 friesian-holstein steers held in individual pens was examined for evidence of infection with bovine spumavirus (bsv). serum was examined for specific antibody by 2 serological procedures, and circulatory leucocytes and throat swabs were examined for the presence of circulatory leucocyte-associated bsv (clab) and saliva-associated bsv (sab). initial tests showed that 7 of the 17 steers had specific antibody to bsv by both serological procedures, and a further steer developed such an ... | 1988 | 2833004 |
| heterogeneity of primate foamy virus genomes. brief report. | dna of the t-lymphotropic simian foamy virus (sfv) lk-3 was cloned in a plasmid vector and used as a probe in comparative dna:dna hybridization studies with primate foamy viruses (sfv serotypes 1, 2, 3, 5, 6, 7, 8, fresh sfv isolates from 12 african green monkeys and one rhesus monkey, as well as human syncytium forming virus). all freshly isolated viruses seemed to be variants of sfv types 2 and 3. especially lk-3 appeared to be closely related to sfv type 3. no hybridization of the lk-3 clone ... | 1988 | 2833201 |
| foamy retroviruses. a virus in search of a disease. | 1988 | 2836735 | |
| evidence for a gapped linear duplex dna intermediate in the replicative cycle of human and simian spumaviruses. | two forms of linear dnas have been found in simian (sfv1) and human (hsrv) spumaviruses: a linear duplex unsensitive to nuclease s1 and a sensitive structure with a single-stranded gap. two nuclease s1 sensitive sites, mapping at the same position for both viruses, have been identified in the gapped structure. using different molecular subgenomic clones of hsrv as probes in southern blot analysis, one s1 site was localized in the 3'ltr and the other near the middle of the molecule at about 6.5 k ... | 1988 | 2847117 |
| animal models for hiv infection and aids: memorandum from a who meeting. | the human immunodeficiency virus is a member of the lentivirus subfamily of the retrovirus family. retroviruses are rna viruses which code for an rna-dependent dna polymerase (reverse transcriptase), which transcribes the rna genome into a dna provirus which, on integration with the host dna, directs the synthesis of new virions. the rna genome consists of a gag gene, which codes for the viral core proteins, a pol gene, which codes for the reverse transcriptase, an env gene, which codes for th ... | 1988 | 2850118 |
| spumaviruses isolated from sources containing agents of non-a, non-b (nanb) hepatitis do not cause nanb hepatitis. | serum and liver tissue containing infective non-a, non-b hepatitis virus were shown to contain a retrovirus-like agent that replicated when inoculated into chimpanzee liver cell cultures in vitro. the virus appeared to assemble its core particles in association with tubular structures reminiscent of those characteristically seen in non-a, non-b hepatitis virus-infected chimpanzee liver in vivo, and produced syncytial cytopathic effects in a number of continuous and a primary mammalian liver cell ... | 1988 | 3130462 |
| latent infection with feline syncytial virus of cell cultures prepared from the kidneys of new-born kittens. | feline syncytial virus infection was detected in 4 out of 30 secondary or tertiary cultures of kidney cells from new-born kittens. such infection was not detected in any primary cell culture. the syncytia-forming virus was readily transmissible by infected cells. one strain was transmissible to heterologous (bovine and canine) secondary cells, but did not infect mdbk and pk-15 cell lines. based on biochemical, untrastructural and serological characteristics, the virus was designated a member of ... | 1988 | 3354195 |
| [pathological findings in lentivirus infected cats]. | this report describes the necropsy findings in 3 cats with a natural t-lymphotropic lentivirus (ftlv) infection. the changes are compared with the "immunodeficiency syndrome" of humans and monkeys. furthermore, the pathogenicity of the ftlv and the significance of a dual infection with ftlv and spumavirus is discussed. | 1989 | 2537529 |
| seroepizootiologic survey of feline syncytial virus infections in domestic cats. | 1989 | 2548027 | |
| serological detection of multiple retroviral infections in cattle: bovine leukemia virus, bovine syncytial virus and bovine visna virus. | individual experimental animals used in our studies on bovine leukemia virus (blv) are routinely screened for the presence of antibodies to the three bovine lymphotropic retroviruses. we utilized these screening methods to examine frozen sera from eight herds for antibodies to blv, bovine visna virus (bvv) and bovine syncytial virus (bsv). serum samples from 235 animals in four dairy and four beef herds were analyzed. detection methods used included indirect fluorescent antibody tests of virus-i ... | 1989 | 2549686 |
| latent simian foamy virus. | 1989 | 2552596 | |
| structural analysis of proviral dna in simian foamy virus (lk-3)-infected cells. | proviral dna of the t-cell lymphotropic simian foamy virus strain lk-3 was characterized. in infected cells, multiple copies of unintegrated linear duplex viral dna of about 13 kbp length are present. nuclease s1 treatment of the dna generated two fragments of 6.5 and 6.0 kbp length that were cloned in phage and plasmid vectors. the proviral dna contains a single-stranded gap of 109 nucleotides. a dna fragment spanning the gap was cloned after completing the double strand by dna synthesis in vit ... | 1989 | 2558626 |
| relationship of the env genes and the endonuclease domain of the pol genes of simian foamy virus type 1 and human foamy virus. | we have molecularly cloned and sequenced a portion of the simian foamy virus type 1 (sfv-1); open reading frames representing the endonuclease domain of the polymerase (pol) and the envelope (env) genes were identified by comparison with the human foamy virus (hfv). unlike the hfv genomic organization, the sfv-1 pol gene overlaps the env gene; thus, the open reading frames reported for hfv between pol and env is not present in sfv-1. comparisons of predicted amino acid sequences of hfv and sfv-1 ... | 1990 | 2152825 |
| transacting transcriptional activation of human spumaretrovirus ltr in infected cells. | the long terminal repeat (ltr) of the human spumaretrovirus (hsrv) was examined with respect to its ability to function as transcriptional promotor in virus-infected and uninfected cells. transient transfections using a plasmid in which the 3' ltr of hsrv was coupled to the bacterial chloramphenicol acetyltransferase (cat) gene revealed that the level of hsrv ltr-directed cat gene expression was markedly increased in hsrv-infected cells compared to uninfected cells. northern blot analysis of cat ... | 1990 | 2158186 |
| identification of the major immunogenic structural proteins of human foamy virus. | we have identified the major immunogenic structural proteins of the human foamy virus (hfv), a distinct member of the foamy virus subfamily of retroviridae. radiolabelled viral proteins were immunoprecipitated from hfv-infected cells by foamy virus antisera of human and non-human primate origin. precipitated viral proteins were in the range of 31k to 170k. labelling of proteins with [14c]glucosamine or with [35s]methionine in the presence of tunicamycin, as well as endo-beta-n-acetylglycosaminid ... | 1990 | 2161055 |
| retroviral infections of the cns of nonhuman primates. | 1990 | 2162289 | |
| existence of feline immunodeficiency virus infection in japanese cat population since 1968. | 1990 | 2168001 | |
| feline retroviruses: a brief review. | representatives of all three retrovirus subfamilies are recognized in the cat: feline leukaemia virus (an oncovirus), feline syncytium-forming virus (a spumavirus) and feline immunodeficiency virus (a lentivirus). each of these is briefly reviewed. | 1990 | 2169669 |
| specific enzyme-linked immunosorbent assay for the detection of antibodies to the human spumavirus. | recombinant plasmid clones were constructed harbouring the central domains of the outer membrane protein and the transmembrane protein of the env gene of human spumaretrovirus (hsrv). the corresponding fusion proteins were expressed in e. coli, purified and used subsequently to produce antibodies against the hsrv env proteins in rabbits. the authenticity of the bacterially produced domain of the hsrv env proteins was shown by radioimmunoprecipitation of the viral env glycoprotein from hsrv-infec ... | 1990 | 2170434 |
| pulmonary lesions induced by 3-methylindole and bovine respiratory syncytial virus in calves. | our objectives were to describe the ultrastructural morphogenesis of pulmonary lesions induced by 3-methylindole in 30- to 45-day-old holstein calves and to determine whether toxic exposure to 3-methylindole exacerbates pulmonary lesions induced by bovine respiratory syncytial virus. administration of 3-methylindole (0.25 g/kg) to calves resulted in interstitial edema and ultrastructural swelling of type-i alveolar epithelial cells and nonciliated bronchiolar epithelial cells as early as 4 to 6 ... | 1990 | 2173450 |
| feline retrovirus infections. | 1990 | 2178110 | |
| simian foamy virus type 1 is a retrovirus which encodes a transcriptional transactivator. | simian foamy viruses, members of the spumavirus subfamily of retroviruses, are found in a variety of nonhuman primates and, as yet, remain to be characterized with respect to genetic structure and regulation of viral gene expression. the genome of simian foamy virus type 1 (sfv-1), an isolate from rhesus macaques, has been molecularly cloned, and the role of the viral long terminal repeat (ltr) in transcriptional control has been investigated. the sfv-1 ltr is 1,621 base pairs long, and sequence ... | 1990 | 2370676 |
| effects of human recombinant alpha and gamma and of highly purified natural beta interferons on simian spumavirinae prototype (simian foamy virus 1) multiplication in human cells. | the present study demonstrates the inhibitory effect of human recombinant interferons (r-hu-ifn) alpha and gamma, and that of highly purified natural human interferon beta on the replication of simian foamy virus type 1 (sfv1) in human av3-cell cultures. all ifn led to strong inhibition of the sfv1 cytopathic effect. electron microscopy showed a 70 to 95% decrease in viral particles. significant inhibition of virus-associated reverse transcriptase activity was found in supernatant fluids of infe ... | 1990 | 1691523 |
| molecular differences between two immunologically related spumaretroviruses: the human prototype hsrv and the chimpanzee isolate sfv6. | a comparative study at the genomic and protein level was performed between two immunologically related spumaretroviruses, the human hsrv and the simian sfv6. cross immunoprecipitation analysis with specific polyclonal and monoclonal antisera indicates shared antigenic determinants. however, restriction analysis of the viral dnas and thermal stability of the hybrids demonstrate that hsrv and sfv6 are two different isolates. | 1990 | 1697180 |
| analysis of splicing patterns of human spumaretrovirus by polymerase chain reaction reveals complex rna structures. | mapping of transcripts of the human foamy virus genome was carried out in permissive human embryonic fibroblast cells by northern blot hybridization and s1 nuclease analysis. since several splice sites that are localized within a relatively narrow genomic region were detected, the polymerase chain reaction (pcr) was employed, and cloning and sequencing of the splice site junctions of the corresponding viral cdnas were subsequently performed. all spumavirus transcripts have a common but relativel ... | 1991 | 1846194 |
| the transcriptional transactivator of human foamy virus maps to the bel 1 genomic region. | the human foamy virus (hfv) genome possesses three open reading frames (bel 1, 2, and 3) located between env and the 3' long terminal repeat. by analogy to other human retroviruses this region was selected as the most likely candidate to encode the viral transactivator. results presented here confirmed this and showed further that a deletion introduced only into the bel 1 open reading frame of a plasmid derived from an infectious molecular clone of hfv abolished transactivation. in contrast, del ... | 1991 | 1846970 |
| the role of passive immunity in bovine respiratory syncytial virus-infected calves. | the role of passive immunity in bovine respiratory syncytial virus (brsv) infections in neonatal calves was evaluated. calves were divided into groups as follows: colostrum-deprived, sham-inoculated; colostrum-deprived, brsv-inoculated; and colostrum-fed, brsv-inoculated. calves were inoculated with a low-passage field isolate of brsv for 4 consecutive days by a combined respiratory tract route and were euthanized 6 days after receiving the last inoculation. arterial oxygen tension (pao2) decrea ... | 1991 | 1847400 |
| further characterization of the gapped dna intermediates of human spumavirus: evidence for a dual initiation of plus-strand dna synthesis. | we recently reported the presence of linear duplex dna intermediates with a gap in the middle of the molecules in the replicative cycle of human (hsrv) and simian (sfv1) spumaviruses. the polypurine tract (ppt), at the 5' boundary of the 3' long terminal repeat, was found to be duplicated in the gap region. by molecular analysis of hsrv proviral dna with region- and strand-specific probes, we have now determined that the gap is located on plus-strand dna and that it is 120 bases long with the 3' ... | 1991 | 1848594 |
| characterization of the transcriptional trans activator of human foamy retrovirus. | the human foamy viruses, or spumaviruses, a distinct subfamily of complex human retroviruses, remain poorly understood both in terms of their pathogenic potential and in terms of the regulatory mechanisms that govern their replication. here, we demonstrate that the human spumaretrovirus shares with other complex human retroviruses the property of encoding a transcriptional trans activator of the homologous viral long terminal repeat. this regulatory protein is encoded by the viral bel-1 open rea ... | 1991 | 1850032 |
| identification of the simian foamy virus transcriptional transactivator gene (taf). | simian foamy virus type 1 (sfv-1), a member of spumavirus subfamily of retroviruses, encodes a transcriptional transactivator that functions to strongly augment gene expression directed by the viral long terminal repeat (ltr). the objective of this study was to identify the viral gene responsible for transactivation. nucleotide sequences between the env gene and the ltr of sfv-1 were determined. the predicted amino acid sequence revealed two large open reading frames (orfs), designated orf-1 (31 ... | 1991 | 1851862 |
| effects of recombinant human alpha a interferon in gnotobiotic calves challenged with respiratory syncytial virus. | the effects of recombinant human alpha a interferon were studied in gnotobiotic calves challenged with respiratory syncytial virus (rsv). gnotobiotic calves given doses of interferon by intramuscular injection over five days showed a marked, dose-related, rise in rectal temperature and depression of circulating leucocytes. differential counts showed decreases in both lymphocytes and neutrophils. no significant pathological differences were found between treated and untreated calves, nor could an ... | 1991 | 1852059 |
| sequence analysis of the simian foamy virus type 1 genome. | we have cloned the simian foamy virus type 1 genome (sfv1) and determined its nucleotide sequence. analysis of this genome reveals, in addition to the usual genes encoding retroviral capsid, reverse transcriptase, and envelope protein (respectively, gag, pol, and env), two open reading frames (orfs) between env and the long terminal repeat with partial homology to the human foamy virus (hfv) bel1 and bel2 genes. the first orf could code for a polypeptide of 312 amino acids (aa) showing 40% homol ... | 1991 | 1647358 |
| distinct cis-acting regions in u3 regulate trans-activation of the human spumaretrovirus long terminal repeat by the viral bel1 gene product. | the human spumaretrovirus (hsrv) genome contains, in addition to coding information for the structural proteins, open reading frames (orfs) for at least three additional genes termed bel1, bel2 and bel3. we report here the localization of the transcriptional activator of hsrv to the bel1 orf. in reporter-based transient expression assays in cos cells utilizing the bacterial cat gene linked to hsrv ltr sequences between -710 and +309 with respect to the transcriptional initiation site, co-express ... | 1991 | 1649456 |
| spumaviruses: a group of complex retroviruses. | 1991 | 1649916 | |
| progressive encephalopathy and myopathy in transgenic mice expressing human foamy virus genes. | transgenic mice carrying the bel region of human foamy retrovirus (hfv) under transcriptional control of its own long terminal repeat expressed the transgene in their central nervous systems and in smooth and striated muscle tissues. the animals developed a progressive degenerative disease of the central nervous system and of the striated muscle. because expression of the transgene was closely correlated with the appearance of structural damage and inflammatory reactions were scanty, the disease ... | 1991 | 1650034 |
| construction of an infectious dna clone of the full-length human spumaretrovirus genome and mutagenesis of the bel 1 gene. | an infectious and full-length molecular clone of genomic human spumaretrovirus (hsrv) dna was constructed. the infectivity of the phsrv13 clone was demonstrated after transfection into susceptible cells by passage of hsrv-specific cytopathic effects as a cell-free culture supernatant, by electron microscopy of hsrv particles in phsrv13 dna-transfected cells, by detection of hsrv transcripts, and by identification of hsrv-encoded proteins with env- and bel-specific antisera in indirect immunofluo ... | 1991 | 1651600 |
| replication and regulation of primate foamy viruses. | 1991 | 1653483 | |
| transcription factor ap-1 modulates the activity of the human foamy virus long terminal repeat. | the human foamy virus (hfv) contains within the u3 region of its long terminal repeat (ltr) three perfect consensus sequences for the binding of the inducible transcription factor ap-1. results of dnase i footprint protection and gel retardation assays demonstrated that proteins in extracts of hela and bhk-21 cells as well as bacterially expressed jun and fos proteins bind to these ap-1 sites. by conducting transient expression assays using chloramphenicol acetyltransferase plasmids carrying ltr ... | 1991 | 1656100 |
| [yearling flu]. | 1991 | 1656545 | |
| structure and transcriptional status of bovine syncytial virus in cytopathic infections. | the genomic structure of bovine syncytial virus (bsv), a virus commonly infecting cattle, was examined in order to gain insights into the nature of viral dna (vdna) intermediates and the transcriptional status of the virus in cytopathic infections. in dog cf2th cells, the dna intermediate of bsv was found to exist predominantly as linear unintegrated vdna (uvd) molecules. the uvd molecules were cloned directly from total cellular dna by addition of ecori linkers and subsequent ligation into the ... | 1991 | 1657718 |
| depression of lymphocyte responses to phytohaemagglutinin in lambs experimentally infected with bovine respiratory syncytial virus. | eight lambs were experimentally infected with bovine respiratory syncytial virus (brsv) and the responses of their peripheral blood lymphocytes to the mitogen phytohaemagglutinin and brsv antigen compared with that of control lambs injected with tissue culture fluid. the lymphocyte transformation responses to phytohaemagglutinin were significantly reduced five and 10 days after experimental infection with brsv (p less than 0.05). it appears that these reductions were associated with cd4+ lymphoc ... | 1991 | 1674620 |