Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| hiv-1 epidemic and public health threat in central african republic. | preliminary sampling among the population of the central african republic suggested a wide genetic variation of hiv-1 subtypes, which indicated multiple introductions of human immunodeficiency virus (hiv) into the country. in response to these findings, dr. timothy j. dondero of the u.s. centers for disease control and prevention led a multicenter group that examined the epidemiologic patterns of hiv-1 in the central african republic. 2250 individuals from 17 sites in 10 cities were tested and ... | 1996 | 12291508 |
| hormone receptor regulation of the human immunodeficiency virus type 1 and type 2 long terminal repeats. | both host cell and viral transcription factors regulate the long terminal repeat (ltr) of human immuno-deficiency virus (hiv) activity and viral replication. using transient transfection, ligand-activated thyroid hormone and 9-cis-retinoic acid receptors (t(3)r and rxr) were found to stimulate hiv-1 and hiv-2 ltr activities. they also stimulated hiv-1 viral production. drosophila sl2 cells that lack sp1 and t(3)r were used to study hiv-1 and hiv-2 ltr activities. both activities were stimulated ... | 1996 | 11725114 |
| prevalence of hiv-2 infection in europe. | the hiv/aids pandemic is primarily caused by hiv-1. another type of virus, hiv-2, is found mainly in certain west african countries in europe, most of the cases of hiv-2 infection described have been in people from africa. the objective of this study was | 1996 | 12631849 |
| transmission electron microscopy on simian immunodeficiency virus-infected cocultures of vervet monkeys. | healthy african green monkeys are the natural reservoirs for certain hiv-related sivs. more research is now focused on these nonhuman primates that are asymptomatic, so as to answer questions of origins, pathogenesis and therapy with respect to hiv in man. the present study involves the isolation and subsequent co-cultivation of siv variants from two healthy vervet monkeys (cercopithecus aethiops pygerythrus). western blots (new lav blot 1 and new lav blot 2, pasteur) revealed sero cross-reactiv ... | 1996 | 17451298 |
| rnas selected in vitro by the hiv-2 tat protein. | the tat proteins of human immunodeficiency virus types 1 (hiv-1) and 2 (hiv-2), termed tat-1 and tat-2, respectively, are essential for efficient viral replication. tat proteins activate viral transcription by binding to the tar rna stem-loop structure at the 5' end of viral transcripts. we used an in vitro selection procedure to identify rnas present in a large sequence pool that are able to bind to purified tat-2 protein. the sequences of the selected rnas demonstrated a consensus feature: 20 ... | 1997 | 11725130 |
| [the detection of human immunodeficiency virus type 1/2 antibody using synthetic peptides]. | four peptides of human immunodeficiency virus (hiv) located in the regions of gp41, gp120, p24 of hiv-1 and gp36 of hiv-2 have been synthesized according to the published amino acid sequences and the positions of antigenetic determinants of viruses by a solid-phase method. an indirect elisa for detecting antibody against hiv 1/2 was established using these synthetic peptides as the coating antigens. we detected 41 control sera provided by national institute for the control of pharmaceutical and ... | 1997 | 15619912 |
| stavudine:pharmacology,clinical use and future role. | stavudine is a nucleoside analogue reverse transcriptase inhibitor of hiv-1 and hiv-2 and demonstrates in vitro activity with an acceptable therapeutic index in a range of t-lymphocyte and haematopoietic precursor cell lines. it is additive or synergistic in vitro with a range of other antiretrovirals, including the proteinase inhibitor saquinavir, in two- and three-way combinations and is active against zidovudine (zdv)-resistant virus. it exhibits excellent oral bioavailability, with cerebrosp ... | 1997 | 15989602 |
| specificity of retroviral proteinases based on substrates containing tyrosine and proline at the site of cleavage. | the retroviral proteinase (pr) plays crucial roles in the viral life cycle, therefore it is a target for chemotherapy. however, resistance rapidly develops due to frequent mutations. studies to determine the common features of the specificity of different retroviral prs may help to design broad spectrum inhibitors and reduce the possibility of viable mutants. we have studied the specificity of various retroviral proteinases including those the pr of hiv-1, hiv-2, equine infectious anemia virus a ... | 1997 | 11173643 |
| the role of stavudine in the management of adults with hiv infection. | combinations of two nucleoside analogue reverse transcriptase inhibitors plus a third agent represent the current standard for antiretroviral therapy. stavudine is a nucleoside analogue that demonstrates in vitro activity against human immunodeficiency virus type 1 (hiv-1) and hiv-2 within an acceptable therapeutic index in a range of t lymphocyte and haematopoietic precursor cell lines. it is additive or synergistic in vitro with a number of other antiretrovirals including protease inhibitors i ... | 1997 | 11327440 |
| anti-hiv activity of n-1-adamantyl-4-aminophthalimide. | the discovery of new leads acting via novel modes of action in the treatment of the human immunodeficiency virus (hiv), the causative agent of aids, remains a challenge. along this line we synthesized and evaluated a series of n-substituted 4-aminophthalimides which were designed according to the models of thalidomide, phenytoin (pht) and ameltolide. from a series of 24 compounds only n-1-adamantyl-4-aminophthalimide was endowed with anti-hiv-1 and -hiv-2 activity in cem cell cultures. | 1997 | 9863507 |
| an hiv type 2 dna vaccine induces cross-reactive immune responses against hiv type 2 and siv. | we have previously reported on the generation of specific functional immune responses after inoculation of animals with expression vectors encoding hiv-1 genes. this article provides the details of the first application of this new technology to induce immune responses against hiv-2. this virus is molecularly and serologically distinct from hiv-1 and is in fact more closely related to the simian immunodeficiency virus (siv). anti-hiv-2 and siv antibodies were induced in mice of three different h ... | 1997 | 9430248 |
| [antigenicity of nine synthetic peptides of human immunodeficiency virus]. | to establish a elisa method to detect the infection of human immunodeficiency virus (hiv), we synthesized nine peptides ranging in length between 10-27 amino acid (aa) of hiv located in the regions of gp41, p24 of hiv-1 and gp36 of hiv-2, according to the published amino acid sequence and the position of antigenic determinants of viruses, by a solid-phase method. we detected 10 positive sera of hiv-1 and 4 positive sera of hiv-2 by a indirect elisa using these synthetic peptides as the coating a ... | 1997 | 9812570 |
| infection of primary human placental fibroblasts with hiv-1, hiv-2, and siv. | cells with fibroblast-like features were isolated from the villous tissue of normal term human placentas. immunocytochemical characterization of the cells showed that they were vimentin-positive but negative for factor-viii, cd14 and cd4. thus, the cells are mesenchymal and are not endothelial cells, macrophages or trophoblast. these cells were exposed to nine different cell-free virus isolates, including seven isolates of human immunodeficiency virus type 1 (hiv-1), one hiv-2 isolate and one si ... | 1997 | 9672589 |
| diagnostic challenges for rapid human immunodeficiency virus assays. performance using hiv-1 group o, hiv-1 group m, and hiv-2 samples. | we sought to determine the ability of seven rapid assays for human immunodeficiency virus (hiv) to detect antibodies in a panel of sera from individuals infected with different types and groups of hiv. | 1997 | 10195230 |
| prevalence of the human immunodeficiency virus among patients with tuberculosis in sierra leone, established from dried blood spots on filter paper. | sierra leone national tuberculosis programme. | 1997 | 9487445 |
| sensitization of rhabdo-, lenti-, and spumaviruses to human serum by galactosyl(alpha1-3)galactosylation. | vesicular stomatitis virus, human immunodeficiency virus type 2, and human foamy virus, which were produced by cell lines expressing galactosyl(alpha1-3)galactosyl (alphagal) sugars, were found to be less stable in human serum than those from alphagal-negative cells, indicating that galactosyl(alpha1-3)galactosylation sensitizes these viruses as well as mammalian type c oncoviruses (rother et al., j. exp. med. 182:1345-1355, 1995; takeuchi et al., nature (london) 379:85-88, 1996) to complement k ... | 1997 | 9223512 |
| expression cloning of new receptors used by simian and human immunodeficiency viruses. | several members of the chemokine-receptor family serve, in conjunction with cd4, as receptors for the entry of human immunodeficiency virus type i (hiv-1) into cells. the principal receptor for entry of macrophage-tropic (m-tropic) hiv-1 strains is ccr5, whereas that for t-cell-line-tropic (t-tropic) strains is cxcr4. unlike hiv-1, infection with either m-tropic or t-tropic strains of simian immunodeficiency virus (siv) can be mediated by ccr5, but not cxcr4. siv strains will also infect cd4+ ce ... | 1997 | 9230441 |
| conversion of 2',3'-dideoxyadenosine (dda) and 2',3'-didehydro-2',3'-dideoxyadenosine (d4a) to their corresponding aryloxyphosphoramidate derivatives markedly potentiates their activity against human immunodeficiency virus and hepatitis b virus. | 2',3'-dideoxyadenosine (dda), 2',3'-didehydro-2',3'-dideoxyadenosine (d4a) and their lipophilic 5'-monophosphate triester (aryloxyphosphoramidate) prodrugs were evaluated for their anti-retrovirus and anti-hepatitis b virus activity in various cell culture models. the aryloxyphosphoramidate derivatives of dda (cf 1093) and d4a (cf 1001) showed markedly superior (100-1000-fold) efficacies than the parent drugs against human immunodeficiency virus type 1 (hiv-1), hiv-2, simian immunodeficiency vir ... | 1997 | 9237655 |
| anonymous testing of newborn infants for hiv antibodies as a basis for estimating prevalence of hiv in childbearing women: the 1991-1994 study in spain. | during 1991-1994, anonymous screening of newborn infants for maternal antibody to human immunodeficiency virus (hiv) was carried out in three regions of spain: valencia, galicia and sevilla. the newborn infants whose heel-stick blood eluates were satisfactory for hiv antibody tests were a consecutive series of 104 876, representing 99.3% of all newborn infants undergoing routine metabolic screening and estimated as comprising at least 98% of all births in the three regions. enzyme immunoassay (e ... | 1997 | 9240862 |
| p24 antigen capture assay for quantification of human immunodeficiency virus using readily available inexpensive reagents. | antigen capture enzyme-linked immunosorbent assay (elisa) for quantitation of the p24 gag protein of human immunodeficiency virus type-1 (hiv-1) is currently the most common method used to demonstrate virus replication both in vivo and in vitro. the present paper describes an elisa employing readily available inexpensive reagents and gives detailed suggestions for optimizing the variables for specific purposes. the assay is as sensitive as commercial kits (25 pg/ml) and has a linear dose respons ... | 1997 | 9245608 |
| the fidelity of 3' misinsertion and mispair extension during dna synthesis exhibited by two drug-resistant mutants of the reverse transcriptase of human immunodeficiency virus type 1 with leu74-->val and glu89-->gly. | the relatively low fidelity of dna synthesis characteristic to the reverse transcriptases (rts) of the aids-causing viruses, human immunodeficiency viruses types 1 and 2 (hiv-1 and hiv-2, respectively) was implicated as a dominant factor that contributes to the genetic hypervariability of these viruses. the formation of 3'-mispaired dna and the subsequent extension of this dna were shown to be key determinants that lead to the error proneness of these rts. as part of our goal to study the struct ... | 1997 | 9249032 |
| differentiation of dual seropositivity to hiv 1 and hiv 2 in ghanaian sera using line immunoassay (innolia). | two hundred serum samples from aids-like patients, blood donors and miscellaneous patients were screened by elisa for hiv 1-2. repeatedly positive samples were confirmed using the western blot (wb). twenty samples that were dual positive were further analysed by innolia, which contains synthetic or recombinant antigens in hiv-1 and hiv-2. only 5 of the samples were dual positive. the need for further analysis of dual wb results is re-emphasized. | 1997 | 9257539 |
| envelope glycoproteins from human immunodeficiency virus types 1 and 2 and simian immunodeficiency virus can use human ccr5 as a coreceptor for viral entry and make direct cd4-dependent interactions with this chemokine receptor. | several members of the chemokine receptor family have recently been identified as coreceptors, with cd4, for entry of human immunodeficiency virus type 1 (hiv-1) into target cells. in this report, we show that the envelope glycoproteins of several strains of hiv-2 and simian immunodeficiency virus (siv) employ the same chemokine receptors for infection. envelope glycoproteins from hiv-2 use ccr5 or cxcr4, while those from several strains of siv use ccr5. our data indicate also that some viral en ... | 1997 | 9261346 |
| shared usage of the chemokine receptor cxcr4 by the feline and human immunodeficiency viruses. | feline immunodeficiency virus (fiv) induces a disease state in the domestic cat that is similar to aids in human immunodeficiency virus (hiv)-infected individuals. as with hiv, fiv can be divided into primary and cell culture-adapted isolates. adaptation of fiv to replicate and form syncytia in the crandell feline kidney (crfk) cell line is accompanied by an increase in the net charge of the v3 loop of the envelope glycoprotein, mirroring the changes observed in the v3 loop of hiv gp120 with the ... | 1997 | 9261358 |
| human immunodeficiency virus types 1 and 2 and simian immunodeficiency virus nef use distinct but overlapping target sites for downregulation of cell surface cd4. | although the nef proteins encoded by human immunodeficiency virus type 1 (hiv-1) and simian immuno-deficiency virus (siv) are known to induce the efficient internalization and degradation of cell surface cd4, it remains unclear whether this process involves a direct interaction between nef and cd4. here, we report that cd4 downregulation by hiv-1 and siv nef requires distinct but overlapping target sites within the cd4 intracytoplasmic domain. in particular, mutation of a glutamic acid residue l ... | 1997 | 9261398 |
| human immunodeficiency virus matrix tyrosine phosphorylation: characterization of the kinase and its substrate requirements. | during virus assembly, a subset of human immunodeficiency virus (hiv) matrix (ma) molecules is phosphorylated on c-terminal tyrosine. this modification facilitates infection of nondividing cells by allowing for the recruitment of the karyophilic ma into the viral core and preintegration complex. ma tyrosine phosphorylation is accomplished by a cellular protein kinase which is incorporated into virions. in this study, we have investigated the nature of this enzyme as well as the determinants of m ... | 1997 | 9261408 |
| the fidelity of misinsertion and mispair extension throughout dna synthesis exhibited by mutants of the reverse transcriptase of human immunodeficiency virus type 2 resistant to nucleoside analogs. | the aids-causing retroviruses, human immunodeficiency virus types 1 and type 2 (hiv-1 and hiv-2, respectively) undergo extensive genetic variations, which effect their pathogenesis and resistance to drug therapy. it was postulated that this genetic hypervariability results from high rates of viral replication in conjugation with a relatively low fidelity of dna synthesis [typical to the reverse transcriptases (rt) of these retroviruses]. as part of studying structure/function relationship in hiv ... | 1997 | 9431997 |
| hiv-testing study of immigrants with pulmonary tuberculosis. | the increasing prevalence of tuberculosis (tb) and human immunodeficiency virus (hiv), particularly in africa and asia, led us to investigate the prevalence of hiv infection in immigrants with pulmonary tb at the time of arrival in the uk. we performed anonymous hiv testing of stored sera from 39/65 immigrants referred to our unit between january 1991 and december 1994, who had culture-positive pulmonary tb. none of the 39 patients tested was positive for either hiv-1 or hiv-2, and the character ... | 1997 | 9435032 |
| the prevalence of human immunodeficiency virus among drug-dependent patients in jeddah, saudi arabia. | this study was carried out to determine the prevalence of hiv among drug-dependent patients in jeddah. between january 1 1995 and may 31 1996, all the patients admitted into the al amal hospital for drug dependence were screened for hiv by enzyme immunoassay (eia) and confirmed by western blot. those positive by the two tests were questioned about exposure to the risk factors for hiv infection and examined for clinical evidence of acquired immunodeficiency syndrome (aids). of 2628 admitted, 5 te ... | 1997 | 9437619 |
| tuberculosis and human immunodeficiency virus infection in west burkina faso: clinical presentation and clinical evolution. | to study the relationship between human immunodeficiency virus (hiv) infection and tuberculosis (tb) in a west african country. | 1997 | 9441062 |
| t-lymphocytopaenia, opportunistic infections and pathological findings in ghanaian aids patients and their sexual partners. | ninety-nine patients at center for disease control (cdc) clinical stage iv were studied. twelve (12.12%) of these patients turned out to be hiv seronegative. ten out of the 12 hiv negative patients were immunocompetent whereas the other two had proportional decreases in both cd4+ and cd8+ t-lymphocytes. hiv-1, hiv-2, and dual infection, were detected in 51.5%, 2%, and 22.2% respectively of clinical aids patients. the other 12.12% of clinical aids patients were indeterminate for hiv antibodies. a ... | 1997 | 9557423 |
| inhibition of hiv-1, hiv-2 and siv envelope glycoprotein-mediated cell fusion by calmodulin. | calmodulin, an ef-hand protein, inhibited the fusion between cd4+ human cells and cells stably expressing hiv-1 envelope proteins. fusion was also inhibited when hiv-1, hiv-2 or siv envelope glycoproteins were expressed by vaccinia virus (vv) recombinants, but calmodulin did not inhibit syncytia formation induced by measles virus glycoproteins. calmodulin also inhibited fusion induced by vpe17, a vv-recombinant expressing a truncated form of hiv-1gp160 which lacks the two known calmodulin-bindin ... | 1997 | 9282777 |
| production and characterization of monoclonal antibodies to simian immunodeficiency virus envelope glycoproteins. | twelve monoclonal antibodies (mabs), tb1 to tb12, were produced against a soluble vaccinia recombinant envelope glycoprotein (gp140) from simian immunodeficiency virus sivmac251. these mabs recognized siv gp140 with a relatively high affinity (k0.5 from 6.7 x 10(-8) to 4 x 10(-9) m). all the mabs except tb9, tb11, and tb12 cross-reacted with hiv-2 envelope glycoproteins, but none of the 12 mabs recognized those from hiv-1. using a panel of 87 overlapping synthetic peptides containing 20 amino ac ... | 1997 | 9282816 |
| association of human immunodeficiency virus nef protein with actin is myristoylation dependent and influences its subcellular localization. | human immunodeficiency virus (hiv) nef functions are thought to be mediated via interactions with cellular proteins. utilizing zone velocity sedimentation in glycerol gradients we found that recombinant hiv-1 nef non-covalently associates with actin forming a high-molecular-mass complex of 150-300 kda. this nef/actin complex was present in human b and t lymphocytes but not in insect cells and was dependent on the n-terminal myristoylation of nef, whereas the sh3-binding proline motif of nef was ... | 1997 | 9288906 |
| bicyclams, a class of potent anti-hiv agents, are targeted at the hiv coreceptor fusin/cxcr-4. | bicyclams are a novel class of antiviral compounds which are highly potent and selective inhibitors of the replication of hiv-1 and hiv-2. the prototype compound, amd3100, has an ic50 of 1-10 ng/ml, which is a least 100,000 fold lower than the cytotoxic concentration. amd3100 does not inhibit virus binding to the cd4 receptor and based on time-of-addition experiments, has been assumed to interact with the hiv fusion-uncoating process. resistance of hiv-1 strains to amd3100 is associated with the ... | 1997 | 9298754 |
| maintenance of an unusual polypurine tract in hiv-2: stability to passage in culture. | a stretch of purine residues, the polypurine tract (ppt), is found in all retroviruses and is used to initiate plus-strand dna synthesis. while the ppt of most lentiviruses is a homogeneous sequence of purine residues, the ppt of some isolates of the human and simian immunodeficiency viruses is interrupted with a single pyrimidine residue. the rod strain of human immunodeficiency virus type 2 (hiv-2) has such a pyrimidine-containing variant ppt. virus generated from an infectious molecular clone ... | 1997 | 9299633 |
| prevalence of transmissible blood infections among blood donors at the university of maiducuri teaching hospital, maiduguri, nigeria. | before the advent of the acquired immune deficiency syndrome (aids), many countries of the world transfused blood without seriously considering the potential risks of transmission of infectious agents. even after it was shown that the human immunodeficiency virus(hiv) could be transmitted through blood and blood products, many hospitals and clinics in nigeria still continue to transfuse unscreened blood. this study was therefore initiated to highlight the risks of transmitting infectious agents ... | 1997 | 9299819 |
| synthetic-peptide-based enzyme-linked immunosorbent assay for screening human serum or plasma for antibodies to human immunodeficiency virus type 1 and type 2. | a synthetic-peptide-based enzyme-linked immunosorbent assay (eia) capable of screening for antibodies to both human immunodeficiency virus type 1 (hiv-1) and hiv-2 has been developed for use in blood banks and diagnostic laboratories. microtiter wells are coated with two synthetic peptides, one corresponding to the highly conserved envelope region of hiv-1 and another corresponding to the conserved envelope region of hiv-2. overall, sensitivity was 100% in 303 individuals diagnosed with aids and ... | 1997 | 9302212 |
| use of human immunodeficiency virus (hiv) type 1 and 2 recombinant strip immunoblot assay to resolve enzyme immunoassay anti-hiv-2-repeatably reactive samples after anti-hiv-1/2 combination enzyme immunoassay screening. | with the implementation of combination human immunodeficiency virus types 1 and 2 (hiv-1/2) antibody enzyme immunoassay (eia) in donor screening in 1992, the supplemental testing algorithm changed to require the use of a food and drug administration (fda)-licensed hiv-1 western blot (wb) or immunofluorescence assay, as well as an fda-licensed hiv-2 eia. when hiv-2 eia-reactive specimens are identified, further testing to confirm hiv-2 infection is recommended. currently, a licensed hiv-2 supplem ... | 1997 | 9308638 |
| functional analysis of vif genes derived from various primate immunodeficiency viruses. | replication property in cells of human and simian immunodeficiency viruses (hivs and sivs) lacking intact vif gene was evaluated. of 10 vif mutants constructed in vitro of the major four hiv/siv groups, only those derived from hiv-1 and hiv-2/sivmac displayed replication defect. the cell lines non-permissive for the vif mutants of hiv-1 and sivmac were found to be different. to determine whether vif is exchangeable between hiv-1 and sivmac, chimeric virus clones with respect to the vi gene were ... | 1997 | 9311564 |
| rantes and mcp-3 inhibit the replication of t-cell-tropic human immunodeficiency virus type 1 strains (sf-2, mn, and he). | the effects of the c-c chemokines rantes (regulation upon activation normal t-cell expressed and secreted) and mcp-3 (monocyte chemotactic protein 3) on human immunodeficiency virus (hiv) replication in normal human peripheral blood mononuclear cells (pbmc) activated in vitro with phytohemagglutinin (pha) were investigated. the following t-cell line-tropic (t-tropic) hiv strains were tested: hiv type 1 (hiv-1) sf-2, hiv-1 iiib, hiv-1 mn, hiv-1 ndk, hiv-1 he, hiv-1 nl4-3, hiv-2 rod, and hiv-2 eho ... | 1997 | 9311806 |
| the sequence and structure of the 3' arm of the first stem-loop of the human immunodeficiency virus type 2 trans-activation responsive region mediate tat-2 transactivation. | human immunodeficiency virus type 2 (hiv-2) causes aids, but generally after a much longer asymptomatic period than that which follows infection with hiv-1. at the molecular level, hiv-2 is much more closely related to the simian immunodeficiency viruses than to hiv-1 and our previous studies have demonstrated that hiv-2 and hiv-1 enhancer stimulation is mediated by different sets of cellular proteins following t-cell activation. similar to hiv-1, hiv-2 encodes a transactivating protein, tat, wh ... | 1997 | 9311903 |
| generation of neutralizing antibody to the reverse transcriptase of human immunodeficiency virus type 1 by immunizing of mice with an infectious vaccinia virus recombinant. | antibodies inhibiting the reverse transcriptase (rt) of human immunodeficiency virus type-1 (hiv-1) were found to be generated in the serum of mice repeatedly infected with a vaccinia virus recombinant, wrrt, expressing the enzyme. a monoclonal antibody (mab), 7c4, which specifically and almost completely inhibits the rna-dependent dna polymerase activity of hiv-1 rt was produced from a mouse repeatedly immunized with wrrt. 7c4 seems to be specific for hiv-1 among retroviruses: 7c4 inhibited rt ... | 1997 | 9328586 |
| superinfection with human immunodeficiency virus type 2 can reactivate virus production in baboons but is contained by a cd8 t cell antiviral response. | an animal model was used to assess whether resistance to superinfection by human immunodeficiency virus (hiv) can exist in vivo. asymptomatic baboons (papio cynocephalus), previously infected with hiv-2, were first challenged with homologous virus (hiv-2uc2 or hiv-2uc14) and later with heterologous virus (hiv-2uc12). after both virus inoculations, either resistance to viral infection or a transient viremia was observed. the original virus was recovered in 3 baboons, suggesting that reactivation ... | 1997 | 9333153 |
| inhibition of t-tropic hiv strains by selective antagonization of the chemokine receptor cxcr4. | bicyclams are a novel class of antiviral compounds that are highly potent and selective inhibitors of the replication of hiv-1 and hiv-2. surprisingly, however, when the prototype compound amd3100 was tested against m-tropic virus strains such as bal, ada, jr-csf, and sf-162 in human peripheral blood mononuclear cells, the compound was completely inactive. because of the specific and potent inhibitory effect of amd3100 on t-tropic viruses, but not m-tropic viruses, it was verified that amd3100 i ... | 1997 | 9334378 |
| site-specific phosphorylation of the human immunodeficiency virus type-1 rev protein accelerates formation of an efficient rna-binding conformation. | phosphorylation is important in the regulation of many cellular processes, yet the precise role of protein phosphorylation for many rna-binding protein substrates remains obscure. in this report, we demonstrate that phosphorylation of a recombinant human immunodeficiency virus type-1 rev protein promotes rapid formation of an efficient rna-binding state. the apparent dissociation constant for ligand binding is enhanced 7-fold for the protein following phosphorylation; however, phosphate addition ... | 1997 | 9341215 |
| prevalence and risk factors for htlv-ii infection in 913 injecting drug users in stockholm, 1994. | the prevalence and risk factors for acquisition of human t-cell lymphotropic virus type i and ii (htlv-i and ii) were investigated in a prospective study of 913 injecting drug users (idus) in stockholm in 1994. epidemiologic data were recorded, and blood samples were tested for antibodies against htlv-i and htlv-ii; human immunodeficiency virus (hiv) types 1 and 2; and hepatitis a (hav), b (hbv), c (hcv), and d (hdv). positive serologic results for htlv were confirmed by western blot (wb) and po ... | 1997 | 9342259 |
| usage of the coreceptors ccr-5, ccr-3, and cxcr-4 by primary and cell line-adapted human immunodeficiency virus type 2. | the chemokine receptors ccr-5 and cxcr-4, and possibly ccr-3, are the principal human immunodeficiency virus type 1 (hiv-1) coreceptors, apparently interacting with hiv-1 envelope, in association with cd4. cell lines coexpressing cd4 and these chemokine receptors were infected with a panel of seven primary hiv-2 isolates passaged in peripheral blood mononuclear cells (pbmc) and three laboratory hiv-2 strains passaged in t-cell lines. the ccr-5, ccr-3, and cxcr-4 coreceptors could all be used by ... | 1997 | 9343175 |
| promiscuous use of cc and cxc chemokine receptors in cell-to-cell fusion mediated by a human immunodeficiency virus type 2 envelope protein. | the cc chemokine receptors ccr5, ccr2, and ccr3 and the cxc chemokine receptor cxcr4 have been implicated as cd4-associated cofactors in the entry of primary and cell line-adapted human immunodeficiency virus type 1 (hiv-1) strains. cxcr4 is also a receptor for t-cell-line-adapted, cd4-independent strains of hiv-2. with the exception of this latter example, little has been reported on the entry cofactors used by hiv-2 strains. here we show that a cd4-dependent, t-cell-line-adapted hiv-2 strain u ... | 1997 | 9343197 |
| susceptibility of human immunodeficiency virus type 1 group o isolates to antiretroviral agents: in vitro phenotypic and genotypic analyses. | we investigated the phenotypic and genotypic susceptibility of 11 human immunodeficiency virus type 1 (hiv-1) group o strains to nucleoside and nonnucleoside reverse transcriptase (rt) inhibitors and protease inhibitors in vitro. phenotypic susceptibility was determined by using a standardized in vitro assay of rt inhibition, taking into account the replication kinetics of each strain. hiv-1 group m and hiv-2 isolates were used as references. dna from cocultured peripheral blood mononuclear cell ... | 1997 | 9343254 |
| human immunodeficiency virus type 2 envelope glycoprotein binds to cd8 as well as to cd4 molecules on human t cells. | we report here that human immunodeficiency virus type 2 (hiv-2) envelope glycoprotein (gp105), but not hiv-1 gp120, can bind to cd8 molecules as well as to cd4 molecules on human t cells. this phenomenon may lead to differences in the life cycles of hiv-1 and hiv-2, and it may be related to the differences in disease manifestations of hiv-1 and hiv-2 infection, including longer survival of hiv-2-infected patients. | 1997 | 9343259 |
| expression of naturally occurring antisense rna inhibits human immunodeficiency virus type 1 heterologous strain replication. | recently, the presence of human immunodeficiency virus type 1 (hiv-1) rna transcripts with negative-strand polarity has been shown in tissue culture models of acute and persistently infected cells. one of these transcripts encodes a 189 amino acid open reading frame. this highly conserved antisense sequence is complementary to the structured rev-responsive element and extends through the cleavage site of the env protein. we tested the ability of this antisense rna to modulate hiv-1 replication a ... | 1997 | 9349471 |
| dual infection with hepatitis c and b viruses: clinical and histological study in saudi patients. | the purpose of this study was to assess the clinical and histological significance of dual infection with hepatitis c virus and hepatitis b virus. | 1997 | 9356863 |
| early postinfection antiviral treatment reduces viral load and prevents cd4+ cell decline in hiv type 2-infected macaques. | reports of significant reductions in plasma viral load by anti-hiv drugs have raised the possibility that antiviral therapy, if initiated sufficiently early, may result in sustained control of infection and prolonged clinical benefits. we evaluated the effects of intervention coincident with infection using an antiviral nucleoside, d4t, in macaca nemestrina infected with a highly pathogenic isolate of hiv-2 (hiv-2[287]). infection with this virus reproducibly results in high viremia and rapid cd ... | 1997 | 9359657 |
| in vivo evolution of hiv-1 co-receptor usage and sensitivity to chemokine-mediated suppression. | following the identification of the c-c chemokines rantes, mip-1alpha and mip-1beta as major human immunodeficiency virus (hiv)-suppressive factors produced by cd8+ t cells, several chemokine receptors were found to serve as membrane co-receptors for primate immunodeficiency lentiretroviruses. the two most widely used co-receptors thus far recognized, ccr5 and cxcr4, are expressed by both activated t lymphocytes and mononuclear phagocytes. ccr5, a specific rantes, mip-1alpha and mip-1 receptor, ... | 1997 | 9359702 |
| the solution structure of the amino-terminal hhcc domain of hiv-2 integrase: a three-helix bundle stabilized by zinc. | integrase mediates a crucial step in the life cycle of the human immunodeficiency virus (hiv). the enzyme cleaves the viral dna ends in a sequence-dependent manner and couples the newly generated hydroxyl groups to phosphates in the target dna. three domains have been identified in hiv integrase: an amino-terminal domain, a central catalytic core and a carboxy-terminal dna-binding domain. the amino-terminal region is the only domain with unknown structure thus far. this domain, which is known to ... | 1997 | 9368756 |
| utilization of chemokine receptors, orphan receptors, and herpesvirus-encoded receptors by diverse human and simian immunodeficiency viruses. | human immunodeficiency virus type 1 (hiv-1) requires both cd4 and a coreceptor to infect cells. macrophage-tropic (m-tropic) hiv-1 strains utilize the chemokine receptor ccr5 in conjunction with cd4 to infect cells, while t-cell-tropic (t-tropic) strains generally utilize cxcr4 as a coreceptor. some viruses can use both ccr5 and cxcr4 for virus entry (i.e., are dual-tropic), while other chemokine receptors can be used by a subset of virus strains. due to the genetic diversity of hiv-1, hiv-2, an ... | 1997 | 9371556 |
| identification of the v1 region as a linear neutralizing epitope of the simian immunodeficiency virus sivmac envelope glycoprotein. | the sequence variability of viral structure polypeptides has been associated with immune escape mechanisms. the v1 region of simian immunodeficiency virus (siv) is a highly variable region of the sivmac env gene. here, we describe the v1 region as a linear neutralizing epitope. v1 region-specific neutralizing antibodies (nab) were first demonstrated in a rabbit infected with a recombinant vaccinia virus carrying the env gene of human immunodeficiency virus type 2 strain ben (hiv-2ben). since we ... | 1997 | 9371609 |
| human immunodeficiency virus type 1 vpr interacts with hhr23a, a cellular protein implicated in nucleotide excision dna repair. | the human immunodeficiency virus type 1 (hiv-1) vpr gene is an evolutionarily conserved gene among the primate lentiviruses hiv-1, hiv-2, and simian immunodeficiency viruses. one of the unique functions attributed to the vpr gene product is the arrest of cells in the g2 phase of the cell cycle. here we demonstrate that vpr interacts physically with hhr23a, one member of an evolutionarily conserved gene family involved in nucleotide excision repair. interaction of vpr with hhr23a was initially id ... | 1997 | 9371639 |
| hiv and siv envelope glycoproteins induce phospholipase a2 activation in human and macaque lymphocytes. | we investigated the early interactions between hiv-1, hiv-2, and simian immunodeficiency virus (siv) envelope glycoproteins gp120(iiib), gp105(rod), and gp120(mac251), and human and macaque cells of the lymphocytic series. our results demonstrate that the soluble viral glycoproteins induce a specific phospholipase a2 (pla2) activation in lymphocytes through cd4. this pla2 activation was induced after envelope glycoprotein-cd4 interaction and, because of its local membrane-destabilizing effect, m ... | 1997 | 9377118 |
| the use of multiple antigenic peptide (map) in the immunodiagnosis of human immunodeficiency virus infection. | in order to develop an elisa system for the antibody detection of hiv-1 or hiv-2 infections, maps for hiv-1 gp41(584-618) and hiv-2 gp36(574-602) corresponding to the immunodominant regions of hiv-1 gp41 and hiv-2 gp36 were used as coating antigens in the elisa. the maps were synthesized by the solid phase method using fmoc-lys(fmoc)-oh and their molecular weights were confirmed by tricine gel electrophoresis. the maps reacted with all hiv positive sera (64 samples), but did not react with hiv n ... | 1997 | 9385431 |
| intracellular immunization of rhesus cd34+ hematopoietic progenitor cells with a hairpin ribozyme protects t cells and macrophages from simian immunodeficiency virus infection. | evaluation of candidate genes for stem cell gene therapy for acquired immunodeficiency syndrome (aids) has been limited by the difficulty of supporting in vitro t-cell differentiation of genetically modified hematopoietic progenitor cells. using a novel thymic stromal culture technique, we evaluated the ability of a hairpin ribozyme specific for simian immunodeficiency virus (siv) and human immunodeficiency virus type 2 (hiv-2) to inhibit viral replication in t lymphocytes derived from transduce ... | 1997 | 9389699 |
| seroprevalence of hiv-1, hiv-2, and hiv-1 group o in nigeria: evidence for a growing increase of hiv infection. | to determine current data on hiv infection and to further confirm the presence of hiv-1 group o infection in nigeria, 2300 samples from five states were tested for the presence of hiv antibody. a convenience sampling was obtained from pregnant women, tuberculosis (tb) patients, commercial sex workers (csws), blood donors, patients with sexually transmitted diseases (stds), patients with skin diseases, male clients of csws, outpatients suspected to have aids, truck drivers, and community dwellers ... | 1997 | 9390573 |
| expression of human immunodeficiency virus genes using baculovirus expression system. | the structural protein genes of hiv-1 and hiv-2 have been expressed in spodoptera frugiperda (sf) cells using baculovirus expression system. the noncoding flanking sequences of hiv structural genes were removed and a putative ribosome binding site was placed in front of the open reading frame of each gene by using crossover linker mutagenesis. the coding sequences of the gag, pol, env, and vif proteins were inserted into autographa californica nuclear polyhedrosis virus (acnpv) so that hiv genes ... | 1997 | 9406188 |
| detection of human immunodeficiency virus type 1 and type 2 in the female genital tract: implications for the understanding of virus transmission. | risk of perinatal or female to male sexual transmission of hiv is likely to be associated with whether, and at what concentration, the virus is present in the cervical and vaginal secretions of the hiv-infected woman. examining correlates of cervical and vaginal hiv shedding is, therefore, essential for the development of strategies to interrupt hiv transmission. this article presents the rationale for using detection of hiv in the female genital tract as a marker of infectivity, and briefly des ... | 1997 | 9140133 |
| potency comparison of peptidomimetic inhibitors against hiv-1 and hiv-2 proteinases: design of equipotent lead compounds. | hiv-1 and hiv-2 proteinases (pr) are responsible for the processing of viral polyproteins, a step that is crucial for the formation of infectious virus particles. pr represents one of the most important targets for antiviral chemotherapy. inhibitors of hiv-1 pr usually exhibit a 10- to 100-fold weaker affinity for hiv-2 pr. in order to design subnanomolar inhibitors for both hiv-1 and hiv-2 prs, we prepared a series of compounds varying in the type of scissile bond replacement as well as in the ... | 1997 | 9143353 |
| predominance of hiv-1 among patients with aids and aids-related complex in ghana. | we determined the prevalence of hiv among aids and aids-related complex (arc) patients seen within one year in two hospitals in southern ghana. subjects were screened by an elisa procedure for anti-hiv antibodies. specific identification of the hiv type was done with a particle agglutination (pa) kit. all pa-determined dual specimens were then confirmed by western blotting and pepti-lav 1/2 monoepitope kit. virus isolation was attempted from symptomatic patients by co-culturing patient periphera ... | 1997 | 9145571 |
| antiviral properties of palinavir, a potent inhibitor of the human immunodeficiency virus type 1 protease. | palinavir is a potent inhibitor of the human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) proteases. replication of laboratory strains (hiv-1, hiv-2, and simian immunodeficiency virus) and hiv-1 clinical isolates is inhibited by palinavir with 50% effective concentrations ranging from 0.5 to 30 nm. the average cytotoxic concentration of palinavir (35 microm) in the various target cells indicates a favorable therapeutic index. potent antiviral activity is retained with increased doses ... | 1997 | 9145853 |
| conservation and host specificity of vpr-mediated cell cycle arrest suggest a fundamental role in primate lentivirus evolution and biology. | the human immunodeficiency virus type 1 (hiv-1) vpr protein prevents infected cells from passing through mitosis by arresting them in the g2 phase of the cell cycle. vpr is conserved among all primate lentiviruses, suggesting an important role in the virus life cycle. moreover, in this study we show that the ability to cause cell cycle arrest is also conserved in vpr proteins from a wide variety of both tissue culture-passaged and uncultured human (hiv-1 and hiv-2), sooty mangabey (simian immuno ... | 1997 | 9151821 |
| cd4-independent infection by human immunodeficiency virus type 2 strain rod/b: the role of the n-terminal domain of cxcr-4 in fusion and entry. | the human immunodeficiency virus type 2 (hiv-2) strain rod/b can efficiently use the 7tm chemokine receptor cxcr-4 as a primary receptor to enter cd4-negative cells. we have stably expressed cxcr-4 on mink lung mv-1-lu and feline kidney ccc cells (normally restrictive to hiv entry) and have shown efficient fusion, entry, and replication of rod/b. mutation of the two n-linked glycosylation sites on cxcr-4 (n11-->i, and n176-->q) or pretreatment of ccc or mv-1-lu cells expressing wild-type cxcr-4 ... | 1997 | 9151832 |
| role of the first and third extracellular domains of cxcr-4 in human immunodeficiency virus coreceptor activity. | the cxcr-4 chemokine receptor and cd4 behave as coreceptors for cell line-adapted human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2) and for dual-tropic hiv strains, which also use the ccr-5 coreceptor. the cell line-adapted hiv-1 strains lai and ndk and the dual-tropic hiv-2 strain rod were able to infect cd4+ cells expressing human cxcr-4, while only lai was able to infect cells expressing the rat homolog of cxcr-4. this strain selectivity was addressed by using human-rat cxcr-4 chim ... | 1997 | 9151868 |
| growth ability of auxiliary gene mutants of human immunodeficiency virus types 1 and 2 in unstimulated peripheral blood mononuclear cells. | mutational studies on the vif, vpr, vpu, vpx, and nef genes of human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2) were performed to evaluate their biological functions in natural target cells. for this purpose, replication properties of mutant viruses derived from hiv-1 nl strain and hiv-2 gh strain in unstimulated peripheral blood mononuclear cells were determined. vif- viruses of both hiv-1 and hiv-2 did not grow at all in these cells. similarly, no replication of hiv-2 vpx- mutant w ... | 1997 | 9155882 |
| basolateral sorting of the hiv type 2 and siv envelope glycoproteins in polarized epithelial cells: role of the cytoplasmic domain. | in polarized epithelial cell lines, enveloped viruses are directionally released by asymmetric viral budding at specific plasma membrane domains. previous studies have shown that hiv-1 budding and gp160 expression occur on basolateral membranes whereas the release of hiv-1 gag particles, in the absence of the env glycoproteins, is nonpolarized. we have examined the directional transport and surface expression of hiv-2 and siv envelope glycoproteins using vaccinia virus recombinants in vero c1008 ... | 1997 | 9168235 |
| in vitro induction of human immunodeficiency virus type 1 variants resistant to 2'-beta-fluoro-2',3'-dideoxyadenosine. | 2'-beta-fluoro-2',3'-dideoxyadenosine (f-dda) is an acid-stable purine dideoxynucleoside analog active against a wide spectrum of human immunodeficiency virus type 1 (hiv-1) and hiv-2 strains in vitro. f-dda is presently undergoing a phase i clinical trial at the national cancer institute. we induced hiv-1 variants resistant to f-dda by exposing wild-type hiv-1 (hiv-1lai) to increasing concentrations of f-dda in vitro. after 18 passages, the virus was fourfold less sensitive to f-dda than hiv-1l ... | 1997 | 9174190 |
| evolution of hiv-1 coreceptor usage through interactions with distinct ccr5 and cxcr4 domains. | the chemokine receptor cxcr4 functions as a fusion coreceptor for t cell tropic and dual-tropic hiv-1 strains. to identify regions of cxcr4 that are important for coreceptor function, cxcr4-cxcr2 receptor chimeras were tested for the ability to support hiv-1 envelope (env) protein-mediated membrane fusion. receptor chimeras containing the first and second extracellular loops of cxcr4 supported fusion by t tropic and dual-tropic hiv-1 and hiv-2 strains and binding of a monoclonal antibody to cxcr ... | 1997 | 9177234 |
| identification of a chemokine receptor encoded by human cytomegalovirus as a cofactor for hiv-1 entry. | the human cytomegalovirus encodes a beta-chemokine receptor (us28) that is distantly related to the human chemokine receptors ccr5 and cxcr4, which also serve as cofactors for the entry into cells of human immunodeficiency virus-type 1 (hiv-1). like ccr5, us28 allowed infection of cd4-positive human cell lines by primary isolates of hiv-1 and hiv-2, as well as fusion of these cell lines with cells expressing the viral envelope proteins. in addition, us28 mediated infection by cell line-adapted h ... | 1997 | 9188536 |
| protection of human immunodeficiency virus type 2-exposed seronegative macaques from mucosal simian immunodeficiency virus transmission. | at present it is not known which form of immunity would be most effective against infection with human immunodeficiency virus (hiv). to evaluate the possible role of cellular immunity, we examined whether four hiv type 2-exposed but seronegative macaques developed cellular immune responses and determined whether these exposed macaques were resistant to mucosal transmission of simian immunodeficiency virus (siv). following intrarectal challenge with siv, 2 monkeys were protected against detectabl ... | 1997 | 9188561 |
| vpr of simian immunodeficiency virus of african green monkeys is required for replication in macaque macrophages and lymphocytes. | the genomes of simian immunodeficiency viruses isolated from african green monkeys (sivagm) contain a single accessory gene homolog of human immunodeficiency virus type 1 (hiv-1) vpr. this genomic organization differs from that of sivsm-sivmac-hiv-2 group viruses, which contain two gene homologs, designated vpr and vpx, which in combination appear to share the functions of hiv-1 vpr. the in vitro role of the sivagm homolog was evaluated with molecularly cloned, pathogenic sivagm9063-2. these stu ... | 1997 | 9188633 |
| human immunodeficiency virus type 1 and 2 envelope glycoproteins oligomerize through conserved sequences. | hetero-oligomerization between human immunodeficiency virus type 2 (hiv-2) envelope glycoprotein (env) truncation mutants and epitope-tagged gp160 is dependent on the presence of gp41 transmembrane protein (tm) amino acids 552 to 589, a putative amphipathic alpha-helical sequence. hiv-2 env truncation mutants containing this sequence were also able to form cross-type hetero-oligomers with hiv-1 env. hiv-2/hiv-1 hetero-oligomerization was, however, more sensitive to disruption by mutagenesis or i ... | 1997 | 9188654 |
| defective hiv-1 provirus encoding a multitarget-ribozyme inhibits accumulation of spliced and unspliced hiv-1 mrnas, reduces infectivity of viral progeny, and protects the cells from pathogenesis. | a hela t4 cell line containing a defective human immunodeficiency virus type 1 (hiv-1) dna (hd4) was isolated. after transactivation with tat, the hd4 dna was transcribed into a single 3.7-kb mrna that encodes a chimeric cd4/env protein and a multitarget-ribozyme directed against multiple sites within the gp120 coding region of hiv-1 rna (chen et al., 1992). early steps in hiv infection such as entry, reverse transcription, and proviral dna formation were not affected in hd4 cells, and hd4 was e ... | 1997 | 9189769 |
| herpesvirus saimiri-immortalized human t-cells support long-term, high titred replication of human immunodeficiency virus types 1 and 2. | herpesvirus saimiri strain c488 transforms human cd4+ t-lymphocytes to continuous interleukin-2-dependent growth. unlike human t-cell lines derived from tumours or those transformed by human t-lymphotropic virus 1, herpesvirus saimiri-immortalized t-cells (hvs t-cells) retain many functions of primary activated t-lymphocytes. we have characterized the course of human immunodeficiency virus types 1 and 2 (hiv-1/-2) infection in three hvs t-cell lines. our results confirm that hvs t-cells are high ... | 1997 | 9191937 |
| controlling elements in replication of the human immunodeficiency virus type 1. | we have reviewed the genetic structure of hiv-1 from the perspective of understanding viral and cellular regulatory factors that affect viral replication. comparisons are drawn, as appropriate, with other human retroviruses, such as hiv-2, in regard to our understanding of pathogenesis. the synthesis of viral protein and the manner in which viral assembly takes place is also discussed. | 1997 | 9193800 |
| genetic analysis of an hiv type 2 subtype b virus from a spanish individual with aids. | 1997 | 9197384 | |
| human immunodeficiency virus type 2 infection in children. | human immunodeficiency virus type 2 infection is rare in children. this virus can be acquired through transfusion and also by the maternofetal route, especially when the mother becomes infected during pregnancy. diagnosis based on specific serologic tests is simple after the age of 18 months. in the perinatal period, however, viral isolation by culture or polymerase chain reaction dna amplification or both appears to be less sensitive than in the case of human immunodeficiency virus type 1. dise ... | 1997 | 9202626 |
| mode of inhibition of hiv reverse transcriptase by 2-hexaprenylhydroquinone, a novel general inhibitor of rna-and dna-directed dna polymerases. | a natural compound from the red sea sponge ircinia sp., 2-hexaprenylhydroquinone (hph), has been shown to be a general inhibitor of retroviral reverse transcriptases (from hiv-1, hiv-2 and murine leukaemia virus) as well as of cellular dna polymerases (escherichia coli dna polymerase i, and dna polymerases alpha and beta). the pattern of inhibition was found to be similar for all dna polymerases tested. thus the mode of inhibition was studied in detail for hiv-1 reverse transcriptase. hph is a n ... | 1997 | 9210394 |
| the n-terminal arg-rich region of human immunodeficiency virus types 1 and 2 and simian immunodeficiency virus nef is involved in rna binding. | comparison of the amino acid sequences of human immunodeficiency virus (hiv) nef protein and several rna-binding proteins shows similarities in some regions of these proteins. thus, poliovirus protein 2c, an rna-binding protein, shares with nef the sequence yxqq...mdd...dxxd. in addition, both proteins contain an arg-rich motif that, in the case of poliovirus 2c, is involved in rna-binding activity. moreover, the rna-binding, anti-terminator n proteins of lambda, phi21 and p22 phages show sequen ... | 1997 | 9210463 |
| discovery of cyanovirin-n, a novel human immunodeficiency virus-inactivating protein that binds viral surface envelope glycoprotein gp120: potential applications to microbicide development. | we have isolated and sequenced a novel 11-kda virucidal protein, named cyanovirin-n (cv-n), from cultures of the cyanobacterium (blue-green alga) nostoc ellipsosporum. we also have produced cv-n recombinantly by expression of a corresponding dna sequence in escherichia coli. low nanomolar concentrations of either natural or recombinant cv-n irreversibly inactivate diverse laboratory strains and primary isolates of human immunodeficiency virus (hiv) type 1 as well as strains of hiv type 2 and sim ... | 1997 | 9210678 |
| physical interactions between ets and nf-kappab/nfat proteins play an important role in their cooperative activation of the human immunodeficiency virus enhancer in t cells. | the transcriptional regulatory elements of many inducible t-cell genes contain adjacent or overlapping binding sites for the ets and nf-kappab/nfat families of transcription factors. similar arrays of functionally important nf-kappab/nfat and ets binding sites are present in the transcriptional enhancers of human immunodeficiency viruses types 1 and 2 (hiv-1 and hiv-2), suggesting that this pattern of nuclear protein binding sites reflects an evolutionarily conserved mechanism for regulating ind ... | 1997 | 9094628 |
| human immunodeficiency virus type 2 (hiv-2) seroprevalence and characterization of a distinct hiv-2 genetic subtype from the natural range of simian immunodeficiency virus-infected sooty mangabeys. | the extent of zoonotic infections in rural sierra leone, where both feral and pet sooty mangabeys harbor divergent members of the human immunodeficiency virus type 2 (hiv-2)-sooty mangabey simian immunodeficiency virus (sivsm) family, was tested in blood samples collected from 9,309 human subjects in 1993. using hiv-1- and hiv-2-specific enzyme immunoassays and confirmatory western blot analysis to test for antibodies to sivsm-related lentiviruses, we found only nine subjects (0.096%) who tested ... | 1997 | 9094672 |
| location of cis-acting signals important for rna encapsidation in the leader sequence of human immunodeficiency virus type 2. | we used a series of deletion mutations in the untranslated leader region of human immunodeficiency virus type 2 (hiv-2) to seek cis-acting packaging signals. sequences between the 5' major splice donor and the gag initiation codon, where such signals have been identified in hiv-1, appear to make a measurable but very minor contribution to genomic rna packaging, and deletions here had little effect on viral replication in vitro. immediately 5' to the splice donor, two regions were identified whic ... | 1997 | 9094696 |
| [serotypes of the human immunodeficiency virus type 1 in madrid]. | hiv-1 shows high genetic variability, mainly in the genomic region codifying the envelope proteins, which are the most immunogenic. this fact explains the high heterogeneity of antibodies against hiv-1 epitopes. both genetic and serologic diversity has allowed to classify hiv-1 variants in several subtypes (genotypes and serotypes, respectively). the clinical and epidemiological significance of infection caused by each subtype remains to be clarified. | 1997 | 9102487 |
| probing interactions between viral dna and human immunodeficiency virus type 1 integrase using dinucleotides. | retroviral integrases are essential for viral replication and represent an attractive chemotherapeutic target. in the current study, we demonstrated the activity of micromolar concentrations of dinucleotides against human immunodeficiency virus type 1 (hiv-1), hiv type 2 (hiv-2), simian immunodeficiency virus, and feline immunodeficiency virus integrases. the structure-activity relationship indicates that 5'-phosphorylation enhances potency and that phosphodiester and sugar modifications affect ... | 1997 | 9106620 |
| seroprevalence and coprevalence of hiv and hbsag in nigerian children with/without protein energy malnutrition. | in order to assess the seroprevalence and coprevalence of hepatitis-b surface antigen (hbsag), human immunodeficiency virus-1 and -2 (hiv-1 and -2) antibodies in nigerian children with/without protein energy malnutrition (pem), we studied plasma specimens of 206 children with pem and 200 apparently healthy reference children aged between 1 and 3 years by enzyme-linked immunosorbent assays (elisa). hiv-seropositive cases were confirmed by immunoblotting (ib). of the children studied, eight (4%) o ... | 1997 | 9107364 |
| human immunodeficiency virus (hiv)-resistant cd4+ ut-7 megakaryocytic human cell line becomes highly hiv-1 and hiv-2 susceptible upon cxcr4 transfection: induction of cell differentiation by hiv-1 infection. | recent findings have shown that the expression of the seven trans-membrane g-protein-coupled cxcr4 (the receptor for the stromal cell-derived factor [sdf]-1 chemokine) is necessary for the entry of t-lymphotropic human immunodeficiency virus (hiv) strains, acting as a coreceptor of the cd4 molecule. in the human system, the role of cxcr4 in hiv infection has been determined through env-mediated cell fusion assays and confirmed by blocking viral entry in cd4+/cxcr4+ cells by sdf-1 pretreatment. w ... | 1997 | 9108384 |
| measurement of levels of human immunodeficiency virus type 1 reverse transcriptase (rt) and rt activity-blocking antibody in human serum by a new standardized colorimetric assay. | standardization and calibration of a new colorimetric assay for detection of reverse transcriptase (rt) was carried out for optimal detection of rt activity-blocking antibody (rtb-ab) in serum. a total of 99 of 100 swedish and 54 of 54 african human immunodeficiency virus type 1 (hiv-1) antibody-positive individuals had rtb-ab. the one rtb-ab-negative hiv-1 serum sample from a swedish individual was obtained early during seroconversion. five of 615 hiv-1-negative sera from tumor patients, pregna ... | 1997 | 9114385 |
| cell cycle inhibitory effects of hiv and siv vpr and vpx in the yeast schizosaccharomyces pombe. | the vpr gene of human immunodeficiency virus type 1 and type 2 (hiv-1, hiv-2) and simian immunodeficiency virus (siv) encodes a small nuclear protein which is virion-associated and assists nuclear transport of the preintegration complex. expression of hiv-1 vpr has been shown to induce differentiation and prevent proliferation of human cells. hiv-1 vpr has also been shown to arrest cell growth and cause morphological defects in yeast. in contrast, the vpx gene of hiv-2 and siv, which shares sequ ... | 1997 | 9126266 |
| the 80's loop (residues 78 to 85) is important for the differential activity of retroviral proteases. | the abundance of structural data available for retroviral proteases affords a unique opportunity to investigate structure activity relationships. our approach attempts to genetically engineer an hiv (human immunodeficiency virus)-1 protease that is functionally equivalent to the hiv-2 and the siv (simian immunodeficiency virus) enzymes and conversely to engineer an hiv-2 protease that is functionally equivalent to the hiv-1 enzyme. for this purpose, the hiv-2 and siv proteases were cloned and ch ... | 1997 | 9126830 |
| solution structure of the hiv-2 tar-argininamide complex. | the trans-activating region (tar) rna-tat protein interaction is important for activation of transciption in the human immunodeficiency virus (hiv). a model complex for this interaction composed of the two base bulge hiv-2 tar and the amide derivative of arginine was studied by multidimensional heteronuclear nmr. because of the improved spectral properties of the hiv-2 tar complex, a larger number of noes in the bulge region were observed than in earlier studies of the hiv-1 tar-argininamide com ... | 1997 | 9126842 |
| cd8+ cytotoxic t lymphocytes of a cynomolgus macaque infected with simian immunodeficiency virus (siv) mac32h-j5 recognize a nine amino acid epitope in siv gag p26. | a detailed analysis of simian immunodeficiency virus (siv)-specific cytotoxic t lymphocyte (ctl) responses and the identification of the proteins and epitopes they target may improve the design of immunotherapeutic interventions and provide insights into aids pathogenesis. here, we identified a new ctl epitope in the siv gag protein, recognized by cd8+ and mhc class i-restricted ctl clones from a long-term asymptomatic cynomolgus macaque (macaca fascicularis) infected with sivmac32h-j5. using ov ... | 1997 | 9129654 |
| human submandibular saliva specifically inhibits hiv type 1. | studies from a number of laboratories have shown the presence of factor(s) in whole, parotid, and submandibular human saliva capable of inhibiting hiv-1 infectivity in vitro. data from our laboratory suggested that the level of anti-hiv-1 activity is higher in submandibular than parotid or whole saliva. previous results obtained with pooled submandibular saliva from seronegative individuals included a filtration step following saliva-virus interaction. in this article, we present data on the hiv ... | 1997 | 9075477 |