| identification and characterization of an hiv-2 antibody-positive blood donor in the united states. | as of june 1, 1992, the food and drug administration recommended that all donated blood be screened for antibodies specific to hiv-2. despite broad serologic surveillance, only two cases of hiv-2 infection had been detected among potential blood and plasma donors since the implementation of the test. | 1998 | 9531953 |
| clinical pattern of human immunodeficiency virus infection (hiv) in pulmonary tuberculosis patients in jos, nigeria. | a study of determine the seroprevalence rate and clinical presentation of hiv-associated pulmonary tuberculosis was carried out in jos between october 1990 and september 1991. out of the 180 newly diagnosed pulmonary tuberculosis patients, 11(6.1%) were confirmed seropositive for hiv-1 and 2. the peak age range for both tuberculosis and hiv infection in both sexes is 20-40 years. the risk of hiv infection was associated with multiple sex partners and blood transfusion. there was no significant d ... | 1996 | 9532299 |
| the role of cytotoxic t-cells in hiv infection. | hiv-specific cytotoxic t lymphocytes (ctl) are believed to play a major role in controlling virus levels through the asymptomatic period of hiv infection. for the rational design of an hiv vaccine, we need to know whether protective immunity can ever develop following hiv exposure in people who remain uninfected. we have detected hiv-specific ctl in 5/6 repeatedly exposed, persistently seronegative female sex-workers in the gambia. their ctl, repeatedly detected over two years, recognise epitope ... | 1998 | 9554277 |
| evaluation of an expanded two-elisa approach for confirmation of reactive serum samples in an hiv-screening programme for pregnant women. | serum specimens were collected from 31,232 pregnant women in amsterdam between 1988 and 1995 in a screening programme for human deficiency virus (hiv) infection. the sera of 56 (0.179%) women tested were confirmed as positive for hiv. a total of 67 sera reacted positive or borderline by the screening enzyme-linked immunosorbent assay (elisa) and indeterminate or negative by hiv-1 western blot; 42 of these specimens were available for evaluation of the strategy for diagnosis of hiv infection. a t ... | 1998 | 9557294 |
| transport of viruses through fetal membranes: an in vitro model of perinatal transmission. | a model system for perinatal transmission of viral infections was developed and transport of infectious virus particles through fetal membranes was investigated. viruses of different families known to cause serious intrauterine infections were selected, including relevant and model viruses: the dna-viruses hsv-1 and -2 as well as the animal herpes viruses bhv-1 and shv-1, the rna-virus bvdv as a model for hepatitis c virus, hiv-1 and -2, and ppv as a model for parvovirus b19. migration of infect ... | 1998 | 9557298 |
| 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 |
| cross-reactions between the cytotoxic t-lymphocyte responses of human immunodeficiency virus-infected african and european patients. | the great variability of protein sequences from human immunodeficiency virus (hiv) type 1 (hiv-1) isolates represents a major obstacle to the development of an effective vaccine against this virus. the surface protein (env), which is the predominant target of neutralizing antibodies, is particularly variable. here we examine the impact of variability among different hiv-1 subtypes (clades) on cytotoxic t-lymphocyte (ctl) activities, the other major component of the antiviral immune response. ctl ... | 1998 | 9557634 |
| structured-tree topology and adaptive evolution of the simian immunodeficiency virus sivsm envelope during serial passage in rhesus macaques according to likelihood mapping and quartet puzzling. | species-specific strains of simian immunodeficiency virus (siv) are nonpathogenic in african primates. the siv strain most closely related to human immunodeficiency virus type 2 (hiv-2) is sivsm, the strain specific to the sooty mangabey (cercocebus atys). infection of asian primates with siv causes aids and allows the study of the adaptive evolution of a lentivirus to replicate efficiently in a new host, providing a useful animal model of hiv infection and aids in humans. serial passage of sivs ... | 1998 | 9557648 |
| simian immunodeficiency virus replicates to high levels in sooty mangabeys without inducing disease. | a serologic survey of primates living in a french zoo allowed identification of three cases of infection with simian immunodeficiency virus in sooty mangabeys (cercocebus atys) (sivsm). viral isolates, which were designated sivsmfr66, sivsmfr74, and sivsmfr85, were obtained after short-term culture of mangabey lymphoid cells. phylogenetic analysis of gag and env sequences amplified directly from mangabey tissues showed that the three sivsmfr were genetically close and that they constituted a new ... | 1998 | 9557672 |
| mutational scan of the human immunodeficiency virus type 2 integrase protein. | retroviral integrase (in) cleaves linear viral dna specifically near the ends of the dna (cleavage reaction) and subsequently couples the processed ends to phosphates in the target dna (integration reaction). in vitro, in catalyzes the disintegration reaction, which is the reverse of the integration reaction. ideally, we would like to test the role of each amino acid in the in protein. we mutagenized human immunodeficiency virus type 2 in in a random way using pcr mutagenesis and generated a set ... | 1998 | 9557677 |
| a broad range of chemokine receptors are used by primary isolates of human immunodeficiency virus type 2 as coreceptors with cd4. | like human immunodeficiency virus type 1 (hiv-1) and simian immunodeficiency virus (siv), hiv-2 requires a coreceptor in addition to cd4 for entry into cells. hiv and siv coreceptor molecules belong to a family of seven-transmembrane-domain g-protein-coupled receptors. here we show that primary hiv-2 isolates can use a broad range of coreceptor molecules, including ccr1, ccr2b, ccr3, ccr4, ccr5, and cxcr4. despite broad coreceptor use, the chemokine ligand sdf-1 substantially blocked hiv-2 infec ... | 1998 | 9557695 |
| prevalence of infection with hiv, hepatitis b and c viruses, in four high risk groups in eritrea. | little is known about the prevalence of infections in different population groups in africa, and about the influence of living conditions on the spread of infections. this study is the first of its kind in the state of eritrea and is expected to serve as an evaluation of the situation in the country. | 1998 | 9562856 |
| mechanism of nef-induced cd4 endocytosis: nef connects cd4 with the mu chain of adaptor complexes. | the nef protein of primate lentiviruses down-regulates the cell surface expression of cd4 and probably mhc i by connecting these receptors with the endocytic machinery. here, we reveal that nef interacts with the mu chains of adaptor complexes, key components of clathrin-coated pits. for human immunodeficiency virus type 2 (hiv-2) and simian immunodeficiency virus (siv) nef, this interaction occurs via tyrosine-based motifs reminiscent of endocytosis signals. mutating these motifs prevents the b ... | 1998 | 9564030 |
| multiply spliced env and nef transcripts of simian immunodeficiency virus from west african green monkey (sivagm-sab). | we have characterized the spliced transcripts of nef and envelope genes of sivagm from african green monkey of the sabaeus subspecies. most of the transcripts we have studied, representing the most abundant mrna species in our assay, have undergone a specific splicing event that removes a part of the trans-activation response (tar) element. this region is predicted to form a stable secondary structure (four stem-loop elements in sivagm-sab) that affects the trans-activation of viral gene express ... | 1998 | 9566554 |
| construction of the chimeric reverse transcriptase of simian immunodeficiency virus sensitive to nonnucleoside reverse transcriptase inhibitor. | a number of structurally diverse compounds have been shown to be potent inhibitors of the dna polymerase activity of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt). the compounds can be grouped into two broad classes; nucleoside analogs and nonnucleoside rt inhibitors. the nonnucleoside rt inhibitors are quite specific for hiv-1 rt but not human immunodeficiency virus type 2 (hiv-2) and simian immunodeficiency virus (siv) rt. we have investigated the property of siv/hiv-1 ... | 1998 | 9570285 |
| mapping the genetic determinants of human immunodeficiency virus type 2 for cell tropism and replication efficiency. | two distinct infectious molecular clones of human immunodeficiency type 2 (hiv-2) were analyzed for their biological properties in six cell lines. fourteen chimeric and ten mutant viruses were constructed from these two viral genomes to localize the genetic determinants responsible for the phenotypes. growth property of the viruses in the cell lines, together with the biochemical data, showed that a major determinant for the viral tropism resides in the env gene. in addition, in some cell lines, ... | 1998 | 9572552 |
| human immunodeficiency virus type 2 vpx-gag interaction. | incorporation of vpx into human immunodeficiency virus type 2 (hiv-2) virus-like particles is mediated by the gag polyprotein. we have identified residues 15 to 40 of gag p6 and residues 73 to 89 of vpx as being necessary for virion incorporation. in addition, we show enhanced in vitro binding of vpx to a chimeric hiv-1/hiv-2 gag construct containing residues 2 to 49 of hiv-2 p6 and demonstrate that the presence of residues 73 to 89 of vpx allows for in vitro binding to hiv-2 gag. | 1998 | 9573303 |
| ccr5 coreceptor utilization involves a highly conserved arginine residue of hiv type 1 gp120. | the seven-transmembrane ccr5 was recently found to double as a coreceptor for a genetically diverse family of human and nonhuman primate lentiviruses. paradoxically, the main region of the envelope protein believed to be involved in ccr5 utilization was mapped to hypervariable region 3, or v3, of the envelope glycoprotein gp120. in this study, we addressed the question of whether functional convergence in ccr5 utilization is mediated by certain v3 residues that are highly conserved among hiv typ ... | 1998 | 9576954 |
| [importance of molecular biology in retrovirus and herpesvirus infections]. | molecular biology has long been used as a tool for basic research in virology. its medical use is recent and has been supported both by numerous technical improvements and the discovery of new human viruses. this is illustrated by the emergence of human immunodeficiency virus (hiv)-1, hiv-2, human t-cell leukemia virus (htlv)-i/ii, and human herpesviruses (hhv) 6, 7 and 8. polymerase chain reaction (pcr) gave a major boost to an extended use of molecular biology techniques. this resulted in a be ... | 1998 | 9577878 |
| htlv-1 infection in a population-based cohort of older persons in guinea-bissau, west africa: risk factors and impact on survival. | in 1989, a population-based cohort of persons aged > or = 50 years was established in an urban area of guinea-bissau, west africa. overall, 346 persons were interviewed in detail about risk behaviors and had capillary blood drawn. among women, 12.4% were htlv-1 seropositive, compared with 4.6% in men. no htlv-2 was found. seropositivity varied considerably according to place of birth and ethnic group. in women, but not in men, htlv-1 seropositivity was strongly associated with early sexual debut ... | 1998 | 9579561 |
| cross-clade recognition of p55 by cytotoxic t lymphocytes in hiv-1 infection. | to evaluate cross-clade recognition of p55 antigen by cytotoxic t lymphocytes (ctl) in persons infected with diverse clades of hiv-1; to facilitate the development of a ctl-inducing vaccine to prevent transmission of multiple clades of hiv-1. | 1998 | 9583596 |
| a serosurvey of haemophilus ducreyi, syphilis, and herpes simplex virus type 2 and their association with human immunodeficiency virus among female sex workers in lagos, nigeria. | to determine the prevalence rates of serological reactivity of haemophilus (h.) ducreyi, treponema pallidum, and herpes simplex virus type 2 (hsv-2) antibodies among female sex workers (fsws) and their association with human immunodeficiency virus (hiv) antibody status. | 1998 | 9587174 |
| human papillomavirus and human immunodeficiency virus infections: relation with cervical dysplasia-neoplasia in african women. | our study assessed the factors associated with cervical squamous intra-epithelial lesions (sils) and invasive cervical cancer, with special attention to human immunodeficiency virus (hiv) and human papillomavirus (hpv) infections. women from 3 outpatient gynecology clinics of abidjan, côte d'ivoire, were screened for cervical abnormalities: 151 women with low-grade sils and 151 controls, 60 with high-grade sils and 240 controls, and 13 with invasive cancer and 65 controls were enrolled in 3 case ... | 1998 | 9590121 |
| cytomegalovirus enteritis: a highly lethal condition requiring early detection and intervention. | cytomegalovirus infection causing symptomatic enteritis is most usually associated with immunosuppressed transplant patients or patients positive for human immunodeficiency virus. most reports studying this illness are small and do not clearly define the risk factors or mortality rates. | 1998 | 9593246 |
| antigenicity of linear and cyclic peptides mimicking the disulfide loops in hiv-2 envelope glycoprotein: synthesis, reoxidation and purification. | the external envelope glycoprotein (gp125) of human immunodeficiency virus type 2 (hiv-2) contains 22 cysteine residues. the positions of the 11 disulfide bridges in hiv-2 gp125 were determined by analogy with the experimental position of the disulfide bonds found in the gp120 of hiv-1. peptides expected to mimic all 11 disulfide-bonded domains containing from 13 to 47 amino acids were synthesized by the solid-phase method according to 9-fluorenylmethoxycarbonyl strategy, except for peptide 5, w ... | 1998 | 9606017 |
| detection of human immunodeficiency virus type 1 (hiv-1) rna in pools of sera negative for antibodies to hiv-1 and hiv-2. | a total of 234 pools were prepared from 10,692 consecutive serum samples negative for antibodies to human immunodeficiency virus type 1 (hiv-1) and hiv-2 collected at five virological laboratories (average pool size, 45 serum samples). pools were screened for the presence of hiv-1 rna by a modified commercial assay (amplicor hiv-1 monitor test) which included an additional polyethylene glycol (peg) precipitation step prior to purification of viral rna (peg amplicor assay). the sensitivity of thi ... | 1998 | 9620372 |
| genetically divergent strains of human immunodeficiency virus type 2 use multiple coreceptors for viral entry. | several members of the seven-transmembrane chemokine receptor family have been shown to serve, with cd4, as coreceptors for entry by human immunodeficiency virus type 1 (hiv-1). while coreceptor usage by hiv-1 primary isolates has been studied by several groups, there is only limited information available concerning coreceptor usage by primary hiv-2 isolates. in this study, we have analyzed coreceptor usage of 15 primary hiv-2 isolates, using lymphocytes from a donor with nonfunctional ccr5 (ccr ... | 1998 | 9620997 |
| role of the sh3-ligand domain of simian immunodeficiency virus nef in interaction with nef-associated kinase and simian aids in rhesus macaques. | the nef gene of the human and simian immunodeficiency viruses (hiv and siv) is dispensable for viral replication in t-cell lines; however, it is essential for high virus loads and progression to simian aids (saids) in siv-infected adult rhesus macaques. nef proteins from hiv type 1 (hiv-1), hiv-2, and siv contain a proline-xaa-xaa-proline (pxxp) motif. the region of nef with this motif is similar to the src homology region 3 (sh3) ligand domain found in many cell signaling proteins. in virus-inf ... | 1998 | 9621042 |
| nonreciprocal packaging of human immunodeficiency virus type 1 and type 2 rna: a possible role for the p2 domain of gag in rna encapsidation. | the ability of human immunodeficiency virus types 1 (hiv-1) and 2 (hiv-2) to cross-package each other's rna was investigated by cotransfecting helper virus constructs with vectors derived from both viruses from which the gag and pol sequences had been removed. hiv-1 was able to package both hiv-1 and hiv-2 vector rna. the unspliced hiv-1 vector rna was packaged preferentially over spliced rna; however, unspliced and spliced hiv-2 vector rna were packaged in proportion to their cytoplasmic concen ... | 1998 | 9621049 |
| coreceptor usage of human immunodeficiency virus type 2 primary isolates and biological clones is broad and does not correlate with their syncytium-inducing capacities. | entry of human immunodeficiency virus type 1 (hiv-1) into target cells is mediated by binding of the surface envelope glycoprotein to the cd4 molecule. interaction of the resulting cd4-glycoprotein complex with alpha- or beta-chemokine receptors, depending on the biological phenotype of the virus, then initiates the fusion process. here, we show that primary hiv-2 isolates and biological clones, in contrast to those of hiv-1, may use a broad range of coreceptors, including ccr-1, ccr-3, ccr-5, a ... | 1998 | 9621102 |
| human immunodeficiency virus-2 infection in baboons is an animal model for human immunodeficiency virus pathogenesis in humans. | to assess disease progression in baboons (papio cynocephalus) that were infected with two human immunodeficiency virus-2 (hiv-2) isolates. | 1998 | 9625420 |
| squamous intraepithelial lesions of the cervix, invasive cervical carcinoma, and immunosuppression induced by human immunodeficiency virus in africa. dyscer-ci group. | squamous intraepithelial lesions (sils) of the cervix are associated with human immunodeficiency virus (hiv) infection, but multiple risk factors must be considered in this context. the authors performed a cross-sectional study to assess the prevalence of and the factors associated with sils and invasive cervical carcinoma (icc). | 1998 | 9635533 |
| differential association of uracil dna glycosylase with sivsm vpr and vpx proteins. | the hiv-1 vpr protein is a virion-associated protein which has been shown to facilitate infection of nondividing macrophages and additionally to alter cell cycle and proliferation status of the infected host cell. hiv-1 vpr also was recently shown to associate with the dna repair enzyme uracil dna glycosylase (udg). this association with a dna repair enzyme is intriguing given that nonprimate lentiviruses encode a dutpase, which, like udg, minimizes the misincorporation of uracil into dna and is ... | 1998 | 9636373 |
| hypervariable epitope constructs representing variability in envelope glycoprotein of siv induce a broad humoral immune response in rabbits and rhesus macaques. | using synthetic peptides, we developed an approach to account for protein epitope variability. we have prepared, in a single synthesis, a cocktail of peptides we have designated a hypervariable epitope construct (hec), which collectively represents much of the in vivo variability seen in an epitope. eight hecs representing the in vivo variability seen throughout the envelope glycoprotein of the simian immunodeficiency virus (siv) were designed and synthesized. the constructs were collectively co ... | 1998 | 9643375 |
| human immunodeficiency virus type 2 lentivirus vectors for gene transfer: expression and potential for helper virus-free packaging. | in addition to the long-term expression of the transgene provided by all retroviral vectors, lentiviruses present the opportunity to transduce nondividing cells and potentially achieve regulated expression. the development of lentiviral vectors requires the design of transfer vectors to ferry the transgene with efficient encapsidation of the transgene rna and with full expression capability, and of a packaging vector to provide packaging machinery in trans but without helper virus production. fo ... | 1998 | 9650621 |
| primary sivsm isolates use the ccr5 coreceptor from sooty mangabeys naturally infected in west africa: a comparison of coreceptor usage of primary sivsm, hiv-2, and sivmac. | genetically divergent strains of simian immunodeficiency virus (siv) from macaques (mac), chimpanzees, and sooty mangabeys (sm) efficiently used rhesus and human ccr5 (r5), but not cxcr4 (xr4), for cell entry. thus far, however, no studies have characterized primary sivsm strains for their use of coreceptors derived from their own natural host. coreceptor usage of two primary, blood-derived sivsm isolates, sivsmsl92b and sivsmfns from naturally infected sooty mangabeys, was determined. primary s ... | 1998 | 9656999 |
| determinants for sensitivity of human immunodeficiency virus coreceptor cxcr4 to the bicyclam amd3100. | the bicyclam amd3100 is a potent and selective inhibitor of the replication of human immunodeficiency virus type 1 and type 2 (hiv-1 and hiv-2). it was recently demonstrated that the compound inhibited hiv entry through cxcr4 but not through ccr5. selectivity of amd3100 for cxcr4 was further indicated by its lack of effect on hiv-1 and hiv-2 infection mediated by the ccr5, ccr3, bonzo, bob, and us28, coreceptors. amd3100 completely blocked hiv-1 infection mediated by a mutant cxcr4 bearing a del ... | 1998 | 9658078 |
| the second extracellular loop of cxcr4 determines its function as a receptor for feline immunodeficiency virus. | the feline homolog of the alpha-chemokine receptor cxcr4 has recently been shown to support cell-cell fusion mediated by cxcr4-dependent strains of human immunodeficiency virus (hiv) and strains of feline immunodeficiency virus (fiv) that have been selected for growth in the crandell feline kidney (crfk) cell line. in this report we demonstrate that expression of cxcr4 alone is sufficient to render cells from diverse species permissive for fusion with fiv-infected cells, suggesting that cxcr4 is ... | 1998 | 9658090 |
| identification of a human immunodeficiency virus type 2 (hiv-2) encapsidation determinant and transduction of nondividing human cells by hiv-2-based lentivirus vectors. | although previous lentivirus vector systems have used human immunodeficiency virus type 1 (hiv-1), hiv-2 is less pathogenic in humans and is amenable to pathogenicity testing in a primate model. in this study, an hiv-2 molecular clone that is infectious but apathogenic in macaques was used to first define cis-acting regions that can be deleted to prevent hiv-2 genomic encapsidation and replication without inhibiting viral gene expression. lentivirus encapsidation determinants are complex and inc ... | 1998 | 9658096 |
| reduction of diagnostic window by new fourth-generation human immunodeficiency virus screening assays. | in order to reduce the diagnostic window between the time of human immunodeficiency virus (hiv) infection and laboratory diagnosis, new screening enzyme-linked immunosorbent assays (elisas) which permit the simultaneous detection of hiv antigen and antibody have been developed. two fourth-generation assays, hiv duo (biomérieux) and hiv combi (boehringer mannheim), for the combined detection of hiv antigen and antibody, were compared with a third-generation assay (hiv-1/hiv-2 3rd generation plus ... | 1998 | 9665998 |
| virion encapsidation of trna(3lys)-ribozyme chimeric rnas inhibits hiv infection. | retroviruses require a specific host cellular trna primer for initiation of first-strand dna synthesis. this primer is bound by viral proteins and copackaged into virions. we have exploited this property in the design and testing of an antiviral ribozyme fused to trna(3lys), the primer used for lentiviral replication, including human immunodeficiency virus (hiv-1 and hiv-2). the chimera consists of trna(3lys) covalently attached to a hammerhead ribozyme, which is targeted to the region immediate ... | 1998 | 9669656 |
| 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 |
| suppression of hiv-2 replication by hiv-1 gag mutants. | gag gene mutants of human immunodeficiency virus type 1 (hiv-1) were analyzed for their potentials of inhibiting the replication of wild-type (wt) hiv-2, the second aids virus, in a single-round of viral replication. of twenty-two hiv-1 gag mutants examined, seven were found to efficiently interfere with the replication of wt hiv-2. some mutants, which can suppress the replication of wt hiv-1, did not show this inhibitory effect. these mutants were defective at the late phase of viral replicatio ... | 1998 | 9675152 |
| the second extracellular loop of cxcr4 is involved in cd4-independent entry of human immunodeficiency virus type 2. | human immunodeficiency virus type 2 (hiv-2) strains that infect cells in the absence of cellular cd4 emerge spontaneously in vitro after culture in cd4+ t-cell lines. the hiv-2rod/b strain can use the cxcr4 chemokine receptor for efficient entry into cd4+ cells. here we have shown that the rat homologue of cxcr4, in the absence of cd4, failed to mediate cd4-independent entry by rod/b. furthermore, using rat-human chimeric cxcr4 receptors we have demonstrated that the second extracellular loop (e ... | 1998 | 9680144 |
| mapping the rna binding sites for human immunodeficiency virus type-1 gag and nc proteins within the complete hiv-1 and -2 untranslated leader regions. | encapsidation of hiv-1 genomic rna is mediated by specific interactions between the rna packaging signal and the gag protein. during maturation of the virion, the gag protein is processed into smaller fragments, including the nucleocapsid (nc) domain which remains associated with the viral genomic rna. we have investigated the binding of glutathione- s -transferase (gst) gag and nc fusion proteins from hiv-1, to the entire hiv-1 and -2 leader rnaencompassing the packaging signal. we have mapped ... | 1998 | 9685481 |
| highly potent synthetic polyamides, bisdistamycins, and lexitropsins as inhibitors of human immunodeficiency virus type 1 integrase. | alignment of the available human immunodeficiency virus type 1 (hiv-1) viral dna termini [u5 and u3 long terminal repeats (ltrs)] shows a high degree of conservation and the presence of a stretch of five or six consecutive adenine and thymine (at) sequences approximately 10 nucleotides away from each ltr end. a series of at-selective minor-groove binders, including distamycin and bisdistamycins, bisnetropsins, novel lexitropsins, and the classic monomeric dna binders hoechst 33258, 4'-diamino-2- ... | 1998 | 9687569 |
| a novel complex of proteins binds the hiv-1 promoter upon virus interaction with cd4. | hiv-1lai13em is a mutant isolate which is less sensitive than the parental hiv-1lai strain to an in vitro treatment with 13b8-2 anti-cd4 monoclonal antibody (mab) that generally inhibits transcription of hiv-1 and hiv-2. in contrast to other clade b viruses, this isolate carries a point mutation g > a at position -188 of the viral promoter. the fact that hiv-1ndk, a clade d virus insensitive to 13b8-2 mab, also carries an a nucleotide at this position has brought our attention to the sequence su ... | 1998 | 9691221 |
| structural role of the 30's loop in determining the ligand specificity of the human immunodeficiency virus protease. | the structural basis of ligand specificity in human immunodeficiency virus (hiv) protease has been investigated by determining the crystal structures of three chimeric hiv proteases complexed with sb203386, a tripeptide analogue inhibitor. the chimeras are constructed by substituting amino acid residues in the hiv type 1 (hiv-1) protease sequence with the corresponding residues from hiv type 2 (hiv-2) in the region spanning residues 31-37 and in the active site cavity. sb203386 is a potent inhib ... | 1998 | 9692985 |
| human immunodeficiency virus seroprevalence among adults treated for out-of-hospital cardiac arrest in seattle, washington, 1989-1993. | to estimate the potential risk of hiv exposure for those providing emergency care for out-of-hospital cardiac arrest in seattle, washington, by surveying the seroprevalence of hiv in the patient population. | 1998 | 9701296 |
| design and evaluation of an in-house hiv-1 (group m and o), sivmnd and sivcpz antigen capture assay. | an enzyme-linked immuno-sorbent assay (elisa) for the detection of human immunodeficiency virus type 1 (hiv-1) and simian immunodeficiency virus (sivcpz/sivmnd) antigens was designed using immunoreagents from naturally infected individuals, and compared to the commercially available vironostika hiv-1 antigen microelisa system (organon teknika). the in-house assay proved to be specific for hiv-1 isolates belonging to group m (a-h) and group o and for sivcpz and sivmnd isolates, but was less sensi ... | 1998 | 9705176 |
| validation of a new immunoblot assay (liatek hiv iii) for confirmation of human immunodeficiency virus infection. | used as a supplemental assay, new anti-human immunodeficiency virus (hiv) immunoblots, employing recombinant and synthetic antigens, appeared to resolve the majority of samples with false-reactive western blot results. would it be possible to completely replace the western blot by an immunoblot for confirmation and exclusion of hiv infection? | 1998 | 9709787 |
| specific interaction of conformational polypeptides derived from hiv gp120 with human t lymphocyte cd4 receptor. | specifically cross-linked peptides (peptomers) have been prepared from the repeating sequences of the c4 domains of glycoproteins 120 present in different isolates of human immunodeficiency virus (hiv). in order to investigate if the hiv c4 peptomers could function as gp120 protein, we have used a novel protein-binding assay to examine if and which components of the peptomers could interact with cd4 receptor in vitro. here, we demonstrate that all the polymeric components of the hiv-1 c4 peptome ... | 1998 | 9719435 |
| the amino terminus of human ccr5 is required for its function as a receptor for diverse human and simian immunodeficiency virus envelope glycoproteins. | the chemokine receptor ccr5 plays a key role in the cd4-dependent entry of human and simian immunodeficiency viruses into target cells. we have mapped the interaction sites on ccr5 for a number of novel anti-ccr5 monoclonal antibodies and have used these to study the role of the ccr5 n-terminal ectodomain in viral entry and to demonstrate differential ccr5 epitope expression on different cell types. deletions of the ccr5 amino terminal domain or substitution with equivalent regions from other ch ... | 1998 | 9721244 |
| hiv-2 and t cell recognition. | hiv-2 is less pathogenic and less transmissible than hiv-1. recent research in relation to deletions in the hiv nef gene and to immune cross-reactions between infections by hiv-2, hiv-1 and simian immunodeficiency virus suggests that t cell recognition and the control of viral replication may be more efficient in hiv-2 infection than in hiv-1 infection. these insights may be crucial to the design of effective vaccines. | 1998 | 9722912 |
| improved detection of hiv-2 proviral dna in dually seroreactive individuals by pcr. | to improve the detection rate of hiv-2 proviral dna in primary uncultured peripheral blood mononuclear cells (pbmc) of hiv-2-seroreactive and hiv-1-hiv-2 dually seroreactive individuals. | 1998 | 9727562 |
| genetic variation in a human immunodeficiency virus type 2 live-virus macaca nemestrina vaccine model. | four pigtailed macaques were inoculated with an infectious, apathogenic human immunodeficiency virus type 2 (hiv-2) molecular clone (hiv-2kr) and subsequently challenged with a highly pathogenic strain, hiv-2287, together with two naive control animals. after challenge, two animals inoculated with a high dose of the immunizing strain were protected from cd4 decline and immunodeficiency. to examine the role of genetic heterogeneity in protection, fragments of the env gene were amplified from peri ... | 1998 | 9733824 |
| mortality among human immunodeficiency virus type 2-positive villagers in rural guinea-bissau is correlated with viral genotype. | we present the results of a 6-year study of 131 human immunodeficiency virus (hiv) type 2 (hiv-2)-infected individuals from a rural population in guinea-bissau. proviral dna sequences 1.3 kb in length were obtained from each individual and, together with clinical data, including proviral load and cd4 and cd8 levels, were used to assess whether viral genotype influences clinical outcome. with a phylogenetic model, a correlation was found between viral genotype and mortality; this correlation was ... | 1998 | 9733826 |
| an orphan seven-transmembrane domain receptor expressed widely in the brain functions as a coreceptor for human immunodeficiency virus type 1 and simian immunodeficiency virus. | both cd4 and an appropriate coreceptor are necessary for infection of cells by human immunodeficiency virus type 1 (hiv-1) and most strains of hiv-2. the chemokine receptors ccr5 and cxcr4 are the major hiv-1 coreceptors, although some virus strains can also utilize alternative coreceptors such as ccr3 to infect cells. in contrast, most if not all simian immunodeficiency virus (siv) strains use ccr5 as a coreceptor, and many siv strains can use ccr5 independently of cd4. in addition, several orp ... | 1998 | 9733831 |
| interaction of hiv-1 nef with the cellular dileucine-based sorting pathway is required for cd4 down-regulation and optimal viral infectivity. | the hiv-1 nef protein is important for pathogenesis, enhances viral infectivity, and regulates the sorting of at least two cellular transmembrane proteins, cd4 and major histocompatibility complex (mhc) class i. although several lines of evidence support the hypothesis that the nef protein interacts directly with the cellular protein sorting machinery, the sorting signal in hiv-1 nef has not been identified. by using a competition assay that functionally discriminates between dileucine-based and ... | 1998 | 9736718 |
| antibodies to the hiv type 2 core protein p26 and vpx: association with disease progression. | a longitudinal cohort study was conducted to define the prevalence and temporal pattern of antibody response to the hiv-2 virion-associated proteins p26gag and vpx. one hundred and forty-one asymptomatic hiv-2-infected women were enrolled, and followed for up to 11 years. eighty-one percent of the subjects had antibodies to p26, and 51% to vpx; response to these two antigens was not correlated. the response to both proteins was determined early in infection, and remained stable over time. the ab ... | 1998 | 9737587 |
| hiv seronegativity in an infant with the acquired immunodeficiency syndrome. | we report the case of an infant with progressive human immunodeficiency virus (hiv) infection and persistent seronegativity. the child had pneumocystis carinii pneumonia at 4 months of age and was documented to be hiv-infected by hiv-1 deoxyribonucleic acid (dna) polymerase chain reaction (pcr), but enzyme-linked immunosorbent assay (elisa) and western blot tests for hiv-1 and hiv-2 specific antibodies remained negative until the infant was 10 months old. this case should increase awareness abou ... | 1998 | 9743066 |
| the simian immunodeficiency virus mnd(gb-1) strain uses cxcr4, not ccr5, as coreceptor for entry in human cells. | the simian immunodeficiency virus (siv) mnd(gb-1) strain, isolated from a mandrill, replicates in a human t cell line, cem cells, and is inhibited by the cxc-chemokines, stromal cell-derived factor 1alpha and 1beta (sdf-1alpha/sdf-1beta), the natural ligands for cxcr4. the ic50 was around 70-80 ng/ml, which corresponds to the ic50 of sdf-1alpha/sdf-1beta for t-tropic human immunodeficiency virus type 1 (hiv-1) and hiv-2. the specific anti-cxcr4 mab 12g5 inhibited replication of sivmnd at an ic50 ... | 1998 | 9747729 |
| sequence diversity of siv(mne) nef in vivo and in vitro. | we have compared nef gene sequences isolated by pcr from peripheral blood lymphocyte dna of macaques which had been inoculated with either biologically or molecularly cloned siv(mne). two samples from each animal obtained either early after infection (week 2-8) or after significant cd4+ depletion (week 21-137) were analyzed. three substitutions in the predicted nef amino acid sequence were seen in all animals at the late time point, and two more in all but one. two of the common exchanges are lo ... | 1998 | 9747946 |
| [left ventricular aneurysm in human immunodeficiency virus infection: a case report]. | the authors report the case of a 30 year old man with a left ventricular aneurysm who was seropositive to hiv 1 and hiv 2. the patient was stage ivc 1 (aids related complex) by the "center for disease control" classification. the clinical presentation was pyrexia, loss of weight, micropolyadenopathy and cardiac failure. the electrocardiogramme showed low voltage in the peripheral leads with a qs morphology in s2, s3 and avf and abrasion, of the r wave in the precordial leads. doppler echocardiog ... | 1998 | 9749229 |
| evaluation of screening kits for the detection of anti-human immunodeficiency virus type 1 and 2 (hiv-1/2) antibodies. | hiv-1/hiv-2 3rd generation (abbott), wellcozyme hiv 1 + 2 (murex), enzygnost anti-hiv 1/-hiv 2 (behring), and genelavia mixt (sanofi diagnostics pasteur) are currently registered by authorities as enzyme immunoassays (eias) for detecting hiv-1/2 infection. the present study dissects these reagents by means of the major antigenic components, assay principles and their actual performance. the performances have been evaluated by their test results in international panels of seroconversion, mixed ti ... | 1995 | 9774997 |
| phosphorylation of triciribine is necessary for activity against hiv type 1. | triciribine (tcn) is a tricyclic nucleoside with known antineoplastic and antiviral activity. it is a potent and selective inhibitor of hiv-1 and hiv-2, including strains known to be resistant to azt or tibo. tcn is phosphorylated to its 5'-monophosphate (tcn-p) by intracellular adenosine kinase (ak), but is not converted to di- or triphosphates. we now report that 5'-phosphorylation is requisite for the activity of tcn against hiv-1. cem cells incubated with tcn at concentrations ranging from 0 ... | 1998 | 9788672 |
| mitogen-activated protein kinase phosphorylates and regulates the hiv-1 vif protein. | the human immunodeficiency virus type 1 (hiv-1) vif protein plays a critical role in virus replication and infectivity. here we show that vif is phosphorylated and regulated by p44/42 mitogen-activated protein kinase (mapk). vif phosphorylation by mapk was demonstrated in vitro as well as in vivo and was shown to occur on serine and threonine residues. two-dimensional tryptic phosphopeptide mapping indicated that vif is phosphorylated by mapk on the same sites in vitro and in vivo. radioactive p ... | 1998 | 9792705 |
| inactivation of viruses by beta-propiolactone in human cryo poor plasma and igg concentrates. | virus inactivation by cold treatment with beta-propiolactone (bpl) was investigated in human cryo poor plasma and purified igg concentrates spiked with relevant human viruses or appropriate animal model viruses. the samples were treated with 0.1 or 0.25% bpl for 300 or 480 min, respectively. residual infectivity was determined by standard microtitration assays on tissue culture cells. the inactivation of all viruses tested was more effective in igg than in plasma. igg: r1=4-5.5 log10 for vesicul ... | 1998 | 9811521 |
| a dileucine motif in hiv-1 nef acts as an internalization signal for cd4 downregulation and binds the ap-1 clathrin adaptor. | human immunodeficiency virus 1 (hiv-1) nef downregulates surface expression of cd4, an integral component of the functional hiv receptor complex, through accelerated endocytosis of surface receptors and diminished transport of cd4 from the golgi network to the plasma membrane. hiv-1 nef also diminishes surface expression of major histocompatibility complex (mhc) class i antigens. in the case of hiv-2 and simian immunodeficiency virus 1 (siv-1) nef, aminoterminal tyrosine-based motifs mediate the ... | 1998 | 9811606 |
| zeta chain of the t-cell receptor interacts with nef of simian immunodeficiency virus and human immunodeficiency virus type 2. | a truncated version of the nef gene of simian immunodeficiency virus sivmac239 capable of encoding amino acids 98 to 263 was used as bait to screen a cdna library from activated lymphocytes in a yeast two-hybrid system. the zeta chain of the t-cell receptor (tcrzeta) was found to interact specifically not only with truncated siv nef in yeast cells but also with full-length glutathione s-transferase (gst)-sivnef fusion protein in vitro. coimmunoprecipitation of tcrzeta with full-length siv nef wa ... | 1998 | 9811718 |
| [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 |
| candidate vaccines protect macaques against primate immunodeficiency viruses. | the preclinical evaluation of the efficacy of potential vaccines against aids requires challenge models. the experimental infection of macaques with simian immunodeficiency virus, human immunodeficiency virus type 2 (hiv-2) or chimeric viruses have proven to be most valuable. the progress made using simian models to assess the efficacy and identify the correlates or mechanism of protection by whole inactivated virus, live attenuated virus or recombinant sub-unit vaccines is reviewed. it is possi ... | 1998 | 9814954 |
| hiv-1 and hiv-2 infections among u.s. peace corps volunteers returning from west africa. | background: the risk of acquiring hiv-1 and hiv-2 infections among expatriates in, and travelers to, west africa is not known. the objective of the study was to examine the risk of human immunodeficiency virus type 1 and type 2 (hiv-1 and hiv-2) infections among peace corps volunteers in west africa. methods: a cross-sectional serosurvey was carried out in 18 west african countries. subjects were 2491 returning peace corps volunteers. the main outcome measure was seropositivity for hiv-1 and hiv ... | 1995 | 9815380 |
| rapid assay for simultaneous detection and differentiation of immunoglobulin g antibodies to human immunodeficiency virus type 1 (hiv-1) group m, hiv-1 group o, and hiv-2. | a rapid immunodiagnostic test that detects and discriminates human immunodeficiency virus (hiv) infections on the basis of viral type, hiv type 1 (hiv-1) group m, hiv-1 group o, or hiv-2, was developed. the rapid assay for the detection of hiv (hiv rapid assay) was designed as an instrument-free chromatographic immunoassay that detects immunoglobulin g (igg) antibodies to hiv. to assess the performance of the hiv rapid assay, 470 hiv-positive plasma samples were tested by pcr and/or western blot ... | 1998 | 9817891 |
| reduction of the diagnostic window with a new combined p24 antigen and human immunodeficiency virus antibody screening assay. | in order to reduce the window phase between time of human immunodeficiency virus (hiv) infection and laboratory diagnosis, new fourth generation screening assays which permit a simultaneous detection of hiv antigen and antibody have been developed. in a multicenter study, a new automated fourth generation assay, enzymun-test hiv combi (boehringer mannheim gmbh) was compared to third generation assay, p24 antigen tests and western blot. a total of 37 seroconversion panels, samples of the early in ... | 1998 | 9820572 |
| binding of hiv-2 envelope glycoprotein to cd8 molecules and related chemokine production. | we recently found that human immunodeficiency virus (hiv)-2 envelope glycoprotein, but not that of hiv-1, could bind to cd4 and cd8 molecules on t cells, and that the binding site of hiv-2 envelope glycoprotein was located on the alpha-chain (but not the beta-chain) of cd8. this study showed that the binding of hiv-2 envelope glycoprotein could induce phosphorylation of protein tyrosine kinase p56lck in cd8+ t cells. we also found that production of beta-chemokines in response to hiv-2 envelope ... | 1998 | 9824478 |
| polyanion inhibitors of hiv and other viruses. 7. polyanionic compounds and polyzwitterionic compounds derived from cyclodextrins as inhibitors of hiv transmission. | new polyanionic compounds were obtained from radical addition of thiomalic acid and mercaptopropionic acid onto perallylated cyclodextrins (cds) under uv irradiation with a catalytic amount of alpha,alpha'-azobis(isobutyronitrile). all these polyanions, bearing 18-48 carboxylate groups, inhibited human immunodeficiency virus type 1 (hiv-1) strain iiib replication in mt-4 cells at a 50% inhibitory concentration (ic50) of 0.1-2.9 microm, while not being toxic to the host cells at concentrations up ... | 1998 | 9836609 |
| natural infection of a homozygous delta24 ccr5 red-capped mangabey with an r2b-tropic simian immunodeficiency virus. | a homozygous 24-bp deletion (delta24) was found in the cc chemokine receptor 5 (ccr5) of 11 out of 15 red-capped mangabeys (rcms), cercocebus torquatus torquatus, both in africa and in an american zoo. the ccr5 delta24 defect encompassed eight amino acids in frame in the fourth transmembrane region. unexpectedly, rcm-009, one of 11 homozygotes (delta24ccr5/ delta24ccr5), was found to be naturally infected with a divergent simian immunodeficiency virus (siv) strain, which was not r5-tropic, but u ... | 1998 | 9841919 |
| [7 new cases of hiv-2 infection recognized in madrid in 1996 and 1997]. | the infection with human immunodeficiency virus type-2 (hiv-2) is endemic in western africa, where it is responsible for many of aids cases. in spain, 72 cases with hiv-2 until december 1997 had been reported, mainly in african immigrants. seven of these cases (4 males and 3 females) were identified during 1996 and 1997. five came from western africa and other two were spanish, one from alicant and the other from vigo. only one out of the seven patients presented clinical manifestations (pneumoc ... | 1998 | 9844454 |
| "hidden" dutpase sequence in human immunodeficiency virus type 1 gp120. | a coding region homologous to the sequence for essential eukaryotic enzyme dutpase has been identified in different genomic regions of several viral lineages. unlike the nonprimate lentiviruses (caprine arthritis- encephalitis virus, equine infectious anemia virus, feline immunodeficiency virus, and visna virus), where dutpase is integrated into the pol coding region, this enzyme has never been demonstrated to be present in the primate lentivirus genomes (human immunodeficiency virus type 1 [hiv ... | 1999 | 9847382 |
| lack of effect of cytoplasmic tail truncations on human immunodeficiency virus type 2 rod env particle release activity. | in addition to its role in receptor binding, the envelope glycoprotein of certain human immunodeficiency virus type 2 (hiv-2) isolates, including rod10, exhibits a biological activity that enhances the release of hiv-2, hiv-1, and simian immunodeficiency virus particles from infected cells. the present study aims at better defining the functional domains involved in this biological activity. to this end, we have characterized the envelope protein of the rod14 isolate of hiv-2, which, despite 95% ... | 1999 | 9847387 |
| chemokine receptor (ccr5) expression in human kidneys and in the hiv infected macaque. | the chemokine receptor, ccr5, has been identified as an essential co-receptor with cd4, which permits entry of human immunodeficiency virus (hiv) into mammalian cells. this receptor may also mediate leukocyte and parenchymal responses to injury by virtue of its binding to locally released chemokines such as rantes, mip-1 alpha and mip-1 beta during inflammation. the localization of ccr5 in human or primate kidney is unknown. in this study we sought to identify sites of ccr5 synthesis through loc ... | 1998 | 9853259 |
| suppression of hiv replication by dominant negative mutants of hiv-1 (review). | various gag mutants of human immunodeficiency virus type 1 (hiv-1) generated in vitro were evaluated for their potentials to suppress the replication of wild-type (wt) virus. a single-round of wt virus replication in the presence of various mutant proteins was quantitatively monitored by transfection and infection experiments. out of 38 mutants examined, 15 were demonstrated to interfere with the replication of wt hiv-1 at early and/or late viral replication phase. some of these mutants were als ... | 1998 | 9855705 |
| dissecting the mode of action of various hiv-inhibitor classes in a stable cellular system. | we describe a stable and sensitive hiv evaluation system, which discriminates hiv-specific membrane fusion and early transcription events and is suitable for high-throughput inhibitor screening. a human lymphocytic line, constitutively producing infectious hiv-1, serves as env-positive donor. a second indicator cell line carries a silent hiv-1 ltr lacz reporter plasmid. a bicellular cocultivation setup allows titration and standardization of "fusion-induced gene stimulation (figs)" events. with ... | 1998 | 9856097 |
| functional roles of hiv accessory proteins for viral replication (review). | numerous lentiviruses, including human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2) of causative agents of human aids as representative, have been recently isolated from various species of primates. the fundamental and most prominent feature of the viruses is the presence of a number of accessory genes in their genomes. extensive biological and biochemical studies have demonstrated that the accessory gene products are not essential for viral replication at least in certain types of cel ... | 1998 | 9857229 |
| infection with the human immunodeficiency virus type 2: epidemiology and transmission (review). | human immunodeficiency virus type 2 (hiv-2) is known to be one of the agents that causes acquired immunodeficiency syndrome (aids). it has been present in west africa since the 1960s and is currently epidemic there. compared with human immunodeficiency virus type 1 (hiv-1), hiv-2 is genomically different. furthermore, it is less prevalent worldwide than hiv-1. in west africa, seropositive rates of hiv-2 are higher in urban versus rural communities, however, there are no gender differences. sexua ... | 1998 | 9858654 |
| 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 |
| live attenuated simian immunodeficiency virus (siv)mac in macaques can induce protection against mucosal infection with sivsm. | to investigate whether vaccination of macaques with attenuated simian immunodeficiency virus (siv)macc8 could induce long-term protective immunity against rectal exposure to sivsm and intravenous exposure to the more divergent hiv-2. | 1998 | 9863867 |
| incidence of human immunodeficiency virus antibody in a prenatal population at a community hospital. | prenatal human immunodeficiency virus (hiv) screening may reduce vertical hiv transmission. we screened 4,419 prenatal sera and found 38 repeatedly reactive specimens with an hiv-1-hiv-2 enzyme-linked immunosorbent assay. western blot analysis confirmed four of these specimens as positive for hiv-1 antibodies. screening detects previously unidentified hiv infections, but false-positive results may also occur. | 1999 | 9874679 |
| in vitro evaluation and characterization of newly designed alkylamidophospholipid analogues as anti-human immunodeficiency virus type 1 agents. | our laboratories first reported two novel classes of complex synthetic lipids, including alkylamidophosphocholines (pc lipid; cp-51) and alkylamidophosphate ester-linked lipid-azt conjugates (lipid-azt conjugates; cp-92), with selective and potent activity against human immunodeficiency virus type 1 (hiv-1). to extend these observations, we synthesized additional pc lipids and lipid-azt conjugates (ink and ink-azt conjugate) to evaluate their structure-activity relationships by testing for selec ... | 1998 | 9875387 |
| broad-spectrum antiviral activity and mechanism of antiviral action of the fluoroquinolone derivative k-12. | the fluoroquinolone derivatives have been shown to inhibit human immunodeficiency virus (hiv) replication at the transcriptional level. we confirmed the anti-hiv activity of the most potent congener, 8-difluoromethoxy-1-ethyl-6-fluoro-1,4-dihydro-7-[4-(2- methoxyphenyl)-1-piperazinyl]-4-quinolone-3-carboxylic acid (k-12), in both acutely and chronically infected cells. k-12 was active against different strains of hiv-1 (including azt- and ritonavir-resistant hiv-1 strains), hiv-2 and simian immu ... | 1998 | 9875393 |
| an approach towards the synthesis of potential metal-chelating tsao-t derivatives as bidentate inhibitors of human immunodeficiency virus type 1 reverse transcriptase. | novel derivatives of the potent human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt) inhibitor tsao-t have been designed, synthesized and tested for their in vitro antiretroviral activity against hiv. these tsao-t derivatives have been designed as potential bidentate inhibitors of hiv-1 rt, which combine in their structure the functionality of a non-nucleoside rt inhibitor (tsao-t) and a bivalent ion-chelating moiety (a beta-diketone moiety) linked through an appropriate spacer ... | 1998 | 9875394 |
| synthesis, structure and in vitro anti-human immunodeficiency virus activity of novel 3-methyl-1h,3h-thiazolo[3,4-a]benzimidazoles. | a series of novel 1-aryl-3-methyl-1h,3h-thiazolo[3,4-a]benzimidazoles, tbz analogues, were synthesized and investigated as anti-human immunodeficiency virus (hiv) agents in order to study the effects of structural modifications on antiviral activity and cytotoxicity. they were proved to inhibit significantly hiv-1 replication in vitro without showing inhibitory activity on hiv-2 or simian immunodeficiency virus. their potency was influenced by the presence of suitable substituents in the phenyl ... | 1998 | 9875396 |
| imidazo[1,5-b]pyridazine-d4t conjugates: synthesis and anti-human immunodeficiency virus evaluation. | in an attempt to combine the human immunodeficiency virus type 1 (hiv-1)-inhibitory capacity of 2',3'-dideoxy-2',3'-didehydronucleoside analogues [nucleoside reverse transcriptase (rt) inhibitors; nrti] and non-nucleoside rt inhibitors (nnrti), we have designed, synthesized and evaluated for their anti-hiv activity several heterodimers of the general formula [d4t]-nh-(ch2)n-nh-[imidazo[1,5-b]pyridazine]. the synthesis of these heterodimers was conducted in three parts. the first part focused on ... | 1998 | 9875400 |
| detection of jc virus in two african cases of progressive multifocal leukoencephalopathy including identification of jcv type 3 in a gambian aids patient. | progressive multifocal leukoencephalopathy (pml) is a fatal demyelinating central nervous system (cns) infection, affecting mainly oligodendrocytes, but also occasional astrocytes. in the usa, europe and asia, pml is caused by the human polyomavirus jc virus (jcv) and in autopsy series occurs in about 4-7% of aids patients. in africa, the prevalence of pml in aids patients is uncertain and the causative agent is unknown. this study reports immunocytochemical and pcr confirmation of pml in the cn ... | 1998 | 9877195 |
| the connection domain is implicated in metalloporphyrin binding and inhibition of hiv reverse transcriptase. | we have shown that heme and zinc protoporphyrin inhibit both human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) reverse transcriptases (rts) and, in combination with other nucleoside and non-nucleoside inhibitors, exert an additive effect on hiv-1 rt inhibition. screening of a phage peptide library against heme resulted in the isolation of a peptide with sequence similarity to sequence 398-407 from the connection subdomain of both hiv-1 and hiv-2 rts, suggesting that this highly cons ... | 1999 | 9880532 |
| regulation of virus release by the macrophage-tropic human immunodeficiency virus type 1 ad8 isolate is redundant and can be controlled by either vpu or env. | the human immunodeficiency virus type 1 (hiv-1) vpu and env proteins are expressed from a bicistronic mrna. to address the biological significance of the coordinated expression of vpu and env, we compared the relative effects on particle release of hiv-1 isolates containing an intact vpu gene or carrying point mutations in its initiation codon or internal deletions, respectively. we found that the primary ad8 isolate, which is unable to express vpu due to a mutation in its translation initiation ... | 1999 | 9882289 |
| characterization of a novel simian immunodeficiency virus (siv) from l'hoest monkeys (cercopithecus l'hoesti): implications for the origins of sivmnd and other primate lentiviruses. | the human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2) appear to have originated by cross-species transmission of simian immunodeficiency virus (siv) from asymptomatically infected african primates. few of the sivs characterized to date efficiently infect human primary lymphocytes. interesting, two of the three identified to infect such cultures (sivsm and sivcpz) have appeared in human populations as genetically related hivs. in the present study, we characterized a novel siv isolate ... | 1999 | 9882304 |
| [effect of hiv envelope glycoprotein on the induction of immune dysregulation in hiv infection]. | the envelope glycoprotein of human immunodeficiency virus (hiv) has been know to play an important role in the induction of immune dysregulation of hiv infection. recent evidence suggests that hiv requires the chemokine receptors as a coreceptor. in addition, we found that hiv-2 (but not hiv-1) envelope glycoprotein can bind to not only cd 4 but also cd 8 molecules on human t cells. based upon these findings, we discuss the effect of hiv envelope glycoprotein on the pathogenic role of hiv infect ... | 1998 | 9884546 |
| changes in neuron size in cynomolgus macaques infected with various immunodeficiency viruses and poliovirus. | human immunodeficiency virus (hiv) infection leads to clinically significant neuronal pathology, but the underlying mechanism remains unclear. infection of rhesus macaques with the simian immunodeficiency virus sivmac251 has been shown to cause atrophy of hippocampal pyramidal cells. the aim of the current investigation was to determine whether sivmac251 and other viruses with differing abilities to cause immune suppression or encephalitis could cause neuronal atrophy in cynomolgus macaques. ani ... | 1998 | 9888157 |