Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| multicenter evaluation of a new, automated enzyme-linked immunoassay for detection of human immunodeficiency virus-specific antibodies and antigen. | a collaborative multicenter study was conducted to evaluate the sensitivity, specificity, and precision of a three-step, fully automated, qualitative microparticle-based enzyme-linked immunoassay (axsym hiv ag/ab combo; abbott laboratories), designed to simultaneously detect (i). antibodies against human immunodeficiency virus type 1 (hiv-1) and/or type 2 (hiv-2) and (ii). hiv p24 antigen. a significant reduction in the hiv seroconversion window was achieved by combining detection of hiv antibod ... | 2004 | 14715727 |
| stampidine prevents mortality in an experimental mouse model of viral hemorrhagic fever caused by lassa virus. | the potential use of microorganisms as agents of biological warfare (bw) is a growing concern. lassa virus, a member of the arenavirus class of hemorrhagic fever (hf) viruses has emerged as a worldwide concern among public health officials. the purpose of the present study was to further elucidate the antiviral activity spectrum of stampidine, a novel nucleoside analog with potent anti-viral activity against the immunodeficiency viruses hiv-1, hiv-2, and fiv, by examining its effects on survival ... | 2004 | 14720304 |
| susceptibility of feline immunodeficiency virus/human immunodeficiency virus type 1 reverse transcriptase chimeras to non-nucleoside rt inhibitors. | to map the determinants of the lack of susceptibility of feline immunodeficiency virus (fiv) reverse transcriptase (rt) to anti human immunodeficiency virus type 1 (hiv-1) non-nucleoside rt inhibitors (nnrtis), a variety of chimeric hiv-1/fiv rts were constructed. the majority of chimeric rts had an affinity (km) for their natural substrates comparable with that of the wild-type hiv-1 and fiv rts, but their catalytic efficacy was decreased. whereas hiv-1 rt could be made entirely insensitive to ... | 2004 | 14722257 |
| isolation of cd4-independent primary human immunodeficiency virus type 1 isolates that are syncytium inducing and acutely cytopathic for cd8+ lymphocytes. | previous studies have established the existence of cd4-independent simian immunodeficiency virus, human immunodeficiency virus type 2 (hiv-2), and laboratory strains of hiv-1. however, whether cd4-independent viruses may also exist in hiv-1-infected patients has remained unclear. we have recently reported the isolation of viruses from an aids patient that were able to infect cd8(+) cells independent of cd4, using cd8 as a receptor. using a similar approach, here we examined viruses from 12 rando ... | 2004 | 14722279 |
| no differences in cellular immune responses between asymptomatic hiv type 1- and type 2-infected gambian patients. | fewer people infected with human immunodeficiency virus (hiv) type 2 progress to acquired immunodeficiency syndrome, compared with those infected with hiv-1. to understand the immune mechanisms leading to slow progression in hiv-2 infection, cell-mediated immune responses were compared between the 2 infections in asymptomatic subjects with a cd4 cell count > or =20%. interferon- gamma release from t lymphocytes and the cytotoxicity of cd8+ t lymphocytes were measured by elispot and 51cr release ... | 2004 | 14745708 |
| conservation of a stepwise, energy-sensitive pathway involving hp68 for assembly of primate lentivirus capsids in cells. | previously we have described a stepwise, energy-dependent pathway for human immunodeficiency virus type 1 (hiv-1) capsid assembly in a cell-free system. in this pathway, gag polypeptides utilize the cellular factor hp68 and assemble into immature capsids by way of assembly intermediates that have defined biochemical characteristics. here we address whether this pathway is universally conserved among primate lentiviruses and can be observed in mammalian cells. we demonstrate that hiv-2 gag associ ... | 2004 | 14747530 |
| chimeric human immunodeficiency virus type 1 (hiv-1) virions containing hiv-2 or simian immunodeficiency virus nef are resistant to cyclosporine treatment. | the viral protein nef and the cellular factor cyclophilin a are both required for full infectivity of human immunodeficiency virus type 1 (hiv-1) virions. in contrast, hiv-2 and simian immunodeficiency virus (siv) do not incorporate cyclophilin a into virions or need it for full infectivity. since nef and cyclophilin a appear to act in similar ways on postentry events, we determined whether chimeric hiv-1 virions that contained either hiv-2 or siv nef would have a direct effect on cyclophilin a ... | 2004 | 14747548 |
| comparative study of adaptive molecular evolution in different human immunodeficiency virus groups and subtypes. | molecular adaptation, as characterized by the detection of positive selection, was quantified in a number of genes from different human immunodeficiency virus type 1 (hiv-1) group m subtypes, group o, and an hiv-2 subtype using the codon-based maximum-likelihood method of yang and coworkers (z. h. yang, r. nielsen, n. goldman, and a. m. k. pedersen, genetics 155:431-449, 2000). the env gene was investigated further since it exhibited the strongest signal for positive selection compared to those ... | 2004 | 14747561 |
| lv2, a novel postentry restriction, is mediated by both capsid and envelope. | the characterization of restrictions to lentivirus replication in cells identifies critical steps in the viral life cycle and potential therapeutic targets. we previously reported that a human immunodeficiency virus type 2 (hiv-2) isolate was restricted to infection in some human cells, which led us to identify a step in the life cycle of hiv-2 detected after reverse transcription but prior to nuclear entry. the block is bypassed with a vesicular stomatitis virus glycoprotein g (vsv-g) envelope ... | 2004 | 14747565 |
| [hiv-2 and htlv-i/ii infections in spain]. | up to december 2002, a total of 56, 566 and 109 cases of human t-lymphotropic virus type 1 (htlv-i), htlv-ii and human immunodeficiency virus type 2 (hiv-2) infection, respectively, were identified in spain. most htlv-i- and hiv-2-infected subjects were immigrants from endemic areas or spaniards who had traveled to, or had sexual contacts with natives from, these areas. in contrast, htlv-ii infection was mainly limited to spanish intravenous drug users (idu) who were frequently coinfected with h ... | 2004 | 14987538 |
| [hiv seroprevalence in ophthalmologic patients of cameroon]. | it is difficult to estimate the exact hiv infection rates in countries such as cameroon because of diagnostic and statistical problems. the majority of people seek help from traditional healers outside the health system. | 2004 | 14999411 |
| evaluation of genetic immunization adjuvants to improve the effectiveness of a human immunodeficiency virus type 2 (hiv-2) envelope dna vaccine. | in an effort to develop a more effective genetic immunization strategy for hiv, we developed an hiv-2 env dna vaccine and evaluated three adjuvant formulations. the gp140 gene from hiv-2(uc2 )was synthesized using mammalian codons and cloned into a plasmid vector that expresses eukaryotic genes at high levels. we found that after three immunizations in mice, a novel cationic liposome formulation (vaxfectin) was superior at inducing systemic and mucosal antibody responses compared to a naked dna, ... | 2004 | 15000750 |
| actinohivin, a novel anti-human immunodeficiency virus protein from an actinomycete, inhibits viral entry to cells by binding high-mannose type sugar chains of gp120. | we searched human immunodeficiency virus (hiv) entry inhibitors and found a novel anti-hiv protein, actinohivin (ah), in a culture filtrate of the newly discovered genus actinomycete longispora albida gen. nov., sp. nov. this paper deals with the mechanism of action of the anti-hiv activity of ah. ah exhibited potent anti-hiv activities against various strains of hiv-1 and hiv-2. ah bound to the glycoprotein gp120 of various strains of hiv-1 and gp130 of simian immunodeficiency virus (siv), but ... | 2004 | 15003531 |
| quantitative real-time pcr on lightcycler for the detection of human immunodeficiency virus type 2 (hiv-2). | similar to hiv-1, the viral load in hiv-2 is a marker of the evolution of infection and the success of therapy. no approved or commercially distributed assay exists to determine the plasma viral load of hiv-2. we therefore developed a quantitative real-time pcr to determine the plasma rna viral load of hiv-2, based on the reference strains rod and eho, which represent subtypes a and b of hiv-2, respectively. after testing several pairs of primers, a set was chosen that recognised the 5'-ltr regi ... | 2004 | 15019261 |
| antiretroviral drug resistance in non-subtype b hiv-1, hiv-2 and siv. | patients infected with hiv-1 of subtype other than b ('non-subtype b') or with hiv-2 are being treated with antiretroviral drugs in increasing numbers. in addition, healthcare providers and laboratory workers working with clinical specimens or animals infected with hiv, siv or shiv are at risk of being exposed to the virus and might require post-exposure prophylactic treatment. thus, it is important to understand the inherent antiviral susceptibility of non-subtype b hiv-1, hiv-2 and siv to curr ... | 2004 | 15040531 |
| susceptibility of hiv-2, siv and shiv to various anti-hiv-1 compounds: implications for treatment and postexposure prophylaxis. | limited information is available on the activity of antiretroviral drugs against human immunodeficiency virus type 2 (hiv-2) and simian immunodeficiency virus (siv) strains to guide their use in treatment or prophylaxis. we evaluated the antiviral activity of 16 approved drugs and one experimental drug, amd3100, against two wild-type hiv-2 (rod and eho) isolates, two strains of siv (mac251 and b670), and two strains of simian-human immunodeficiency virus (shiv) that contain the reverse transcrip ... | 2004 | 15040537 |
| a single amino acid substitution in human apobec3g antiretroviral enzyme confers resistance to hiv-1 virion infectivity factor-induced depletion. | hiv-1 and other retroviruses occasionally undergo hypermutation, characterized by a high rate of g-to-a substitution. recently, the human apolipoprotein b mrna-editing, enzyme-catalytic, polypeptide-like 3g (apobec3g), first identified as cem15, was shown to be packaged into retroviral virions and to deaminate deoxycytidine to deoxyuridine in newly synthesized viral minus-strand dna, thereby inducing g-to-a hypermutation. this innate mechanism of resistance to retroviral infection is counteracte ... | 2004 | 15054139 |
| enigmas and paradoxes: the genetic diversity and prevalence of the primate lentiviruses. | in a comparatively few years a previously unknown virus has spread from its animal host to infect more than 40 million people by the end of 2003, causing an estimated 3 million deaths in that year (world health organization figures). the size of this human immunodeficiency virus (hiv) epidemic and its associated health, social and economic problems make it imperative that we understand how its two types, hiv-1 and hiv-2, have evolved from their simian relatives, the primate lentiviruses (plvs). ... | 2004 | 15078176 |
| anti-hiv-1 gene expressing lentiviral vectors as an adjunctive therapy for hiv-1 infection. | lentiviral based gene therapy may provide a valuable addition to the current anti-hiv arsenal. many lentiviral vector systems have been described including those based on feline immunodeficiency virus (fiv), human immunodeficiency virus 1 (hiv) and 2 (hiv-2/siv) as well as replication incompetent, self-inactivating (sin) vs. conditionally replicating (mobilizable) vectors. lentiviral vectors offer promise in treating hiv-1 infection as they are capable of stably transducing both dividing and non ... | 2004 | 15078182 |
| frequent dual initiation in human immunodeficiency virus-based vectors containing two primer-binding sites: a quantitative in vivo assay for function of initiation complexes. | we previously demonstrated that murine leukemia virus (mlv)-based vectors containing two primer-binding sites (pbss) have the capacity to initiate reverse transcription more than once (y. a. voronin and v. k. pathak, virology 312:281-294, 2003). to determine whether human immunodeficiency virus (hiv)-based vectors also have the capacity to initiate reverse transcription twice, we constructed an hiv type 1 (hiv-1)-based vector containing the hiv-1 pbs, a green fluorescent protein reporter gene (g ... | 2004 | 15113919 |
| prevalence of markers of transfusion transmissible diseases in voluntary and replacement blood donors. | transfusion of safe blood requires a safe donor. the voluntary donor movement encompasses the concept of a donor who is free from transfusion transmissible infections. it is now mandatory to screen blood for hepatitis b surface antigen, antibodies to hiv-1 and hiv-2, antibodies to hepatitis c virus, syphilis and malarial parasites. | 2004 | 15115227 |
| the crystal structure of the monomeric reverse transcriptase from moloney murine leukemia virus. | reverse transcriptases (rts) are multidomain enzymes of variable architecture that couple both rna- and dna-directed dna polymerase activities with an rnase h activity specific for an rna:dna hybrid in order to replicate the single-stranded rna genome of the retrovirus. previous structural work has been reported for the heterodimeric hiv-1 and hiv-2 rts. we now report the first crystal structure of the full-length moloney murine leukemia virus (mmlv) rt at 3.0 a resolution. the structure reveals ... | 2004 | 15130474 |
| current status of the non-nucleoside reverse transcriptase inhibitors of human immunodeficiency virus type 1. | almost fifteen years ago, the first non-nucleoside reverse transcriptase (rt) inhibitor (nnrti) lead compounds have been discovered. nowadays, three nnrtis are approved for treatment of hiv-1-infected individuals and several others are subject of (advanced) clinical trials. although the nnrtis target hiv-1 rt, they are clearly different from the nucleoside rt inhibitors (nrtis). they are highly selective for hiv-1 and do not inhibit hiv-2 or any other (retro)virus. they target hiv-1 rt by a dire ... | 2004 | 15134549 |
| human immunodeficiency virus type 2 dna vaccine provides partial protection from acute baboon infection. | we determined if the genetic adjuvants, granulocyte-macrophage colony stimulating factor (gm-csf) and b7-2, could improve the immunogenicity and efficacy of an hiv-2 dna vaccine. the vaccine consisted of the hiv-2 tat, nef, gag, and env genes synthesized using optimized codons and formulated with cationic liposomes. baboons (papio cynocephalus hamadryas) were immunized by the intramuscular, intradermal, and intranasal routes with these expression constructs and challenged with hiv-2(uc2) by the ... | 2004 | 15149785 |
| a second human antiretroviral factor, apobec3f, is suppressed by the hiv-1 and hiv-2 vif proteins. | the hiv-1 vif protein suppresses the inhibition of viral replication caused by the human antiretroviral factor apobec3g. as a result, hiv-1 mutants that do not express the vif protein are replication incompetent in 'nonpermissive' cells, such as primary t cells and the t-cell line cem, that express apobec3g. in contrast, vif-defective hiv-1 replicates effectively in 'permissive' cell lines, such as a derivative of cem termed cem-ss, that do not express apobec3g. here, we show that a second human ... | 2004 | 15152192 |
| chronic hiv-2 infection protects against total cd4+ cell depletion and rapid disease progression induced by shiv89.6p challenge. | to better understand hiv-1 sexual transmission risk, we have studied the susceptibility of hiv-2-exposed, uninfected (eu) female pig-tailed macaques to intravaginal (ivag) re-challenge with the homologous hiv-2 strain, followed by heterologous shiv89.6p. | 2004 | 15166528 |
| tracking global patterns of n-linked glycosylation site variation in highly variable viral glycoproteins: hiv, siv, and hcv envelopes and influenza hemagglutinin. | human and simian immunodeficiency viruses (hiv and siv), influenza virus, and hepatitis c virus (hcv) have heavily glycosylated, highly variable surface proteins. here we explore n-linked glycosylation site (sequon) variation at the population level in these viruses, using a new web-based program developed to facilitate the sequon tracking and to define patterns (www.hiv.lanl.gov). this tool allowed rapid visualization of the two distinctive patterns of sequon variation found in hiv-1, hiv-2, an ... | 2004 | 15175256 |
| expression and biochemical analysis of the entire hiv-2 gp41 ectodomain: determinants of stability map to n- and c-terminal sequences outside the 6-helix bundle core. | the folding of hiv gp41 into a 6-helix bundle drives virus-cell membrane fusion. to examine the structural relationship between the 6-helix bundle core domain and other regions of gp41, we expressed in escherichia coli, the entire ectodomain of hiv-2(st) gp41 as a soluble, trimeric maltose-binding protein (mbp)/gp41 chimera. limiting proteolysis indicated that the cys-591-cys-597 disulfide-bonded region is outside a core domain comprising two peptides, thr-529-trp-589 and val-604-ser-666. a bioc ... | 2004 | 15178320 |
| hiv type 2 primary isolates induce a lower degree of apoptosis "in vitro" compared with hiv type 1 primary isolates. | to determine whether subtypes of hiv-1 and hiv-2 vary in their ability to induce t cell apoptosis in vitro, human peripheral blood mononuclear cells (pbmc) from healthy donors and cem.nkr-ccr5 cells were infected with a variety of hiv-1 and hiv-2 isolates in vitro. apoptotic cell levels and chemokine and cytokine production were analyzed. significant variations in cytopathic effects following in vitro infection with primary isolates of hiv-1 or hiv-2 subtypes were observed in pbmcs. the percent ... | 2004 | 15186525 |
| current status and potential application of iscoms in veterinary medicine. | the immune stimulating complex (iscom) is a 40 nm nanoparticle used as a delivery system for vaccine antigens, targeting the immune system both after parenteral and mucosal administration. the iscom is made up of saponin, lipids and antigen usually held together by hydrophobic interaction between these three components. the compulsory elements to form the iscom structure are cholesterol and saponin. when the antigen is omitted the iscom-matrix is formed. there are a number of saponins that can f ... | 2004 | 15191787 |
| potent neutralizing serum immunoglobulin a (iga) in human immunodeficiency virus type 2-exposed igg-seronegative individuals. | the mechanisms behind the resistance to human immunodeficiency virus type 2 (hiv-2) infection are still not fully understood. in the present study, we explored the hiv-2-specific humoral serum immunoglobulin a (iga) immune response in hiv-2-exposed igg-seronegative (egsn) individuals. serum samples from heterosexual egsn individuals and their known hiv-2-infected partners, as well as controls originating from guinea-bissau in africa, were studied. antibody reactivity to native and recombinant en ... | 2004 | 15194778 |
| differential regulation of human immunodeficiency virus type 2 and simian immunodeficiency virus promoter activity. | promoter activity of the hiv-1 long terminal repeat (ltr) is largely dependent on intact nf-kb and spi binding sites in the u3 region. in contrast, upstream ltr sequences allow efficient simian immunodeficiency virus (sivmac) transcription in the absence of the core enhancer promoter region. in the present study, we investigated whether the regulation of hiv-2 rod ltr activity is more reminiscent of hiv-1 having the same host or of sivmac239 belonging to the same phylogenetic group. viral promot ... | 2004 | 15207635 |
| hiv-2-infected individuals with undetectable plasma viremia carry replication-competent virus in peripheral blood lymphocytes. | using an optimized hiv co-culture protocol it was possible to isolate infectious hiv-2 variants from 6 hiv-2-infected individuals who had undetectable plasma viremia and maintained high cd4 t-cell numbers for prolonged periods. this shows for the first time that hiv-2-infected individuals with no demonstrable in vivo virus production carry replication-competent virus in peripheral blood mononuclear cells (pbmcs). the frequency of pbmcs with infectious virus was low, ranging from 0.01-0.9 infecti ... | 2004 | 15213560 |
| elevated expression of gm3 in receptor-bearing targets confers resistance to human immunodeficiency virus type 1 fusion. | gm3, a major ganglioside of t lymphocytes, promotes human immunodeficiency virus type 1 (hiv-1) entry via interactions with hiv-1 receptors and the viral envelope glycoprotein (env). increased gm3 levels in t lymphocytes and the appearance of anti-gm3 antibodies in aids patients have been reported earlier. in this study, we investigated the effect of gm3 regulation on hiv-1 entry by utilizing a mouse cell line (b16f10), which expresses exceptionally high levels of gm3. strikingly, b16 cells bear ... | 2004 | 15220409 |
| the phenylmethylthiazolylthiourea nonnucleoside reverse transcriptase (rt) inhibitor msk-076 selects for a resistance mutation in the active site of human immunodeficiency virus type 2 rt. | the phenylmethylthiazolylthiourea (pett) derivative msk-076 shows, besides high potency against human immunodeficiency virus type 1 (hiv-1), marked activity against hiv-2 (50% effective concentration, 0.63 microm) in cell culture. time-of-addition experiments pointed to hiv-2 reverse transcriptase (rt) as the target of action of msk-076. recombinant hiv-2 rt was inhibited by msk-076 at 23 microm. as was also found for hiv-1 rt, msk-076 inhibited hiv-2 rt in a noncompetitive manner with respect t ... | 2004 | 15220416 |
| prevalence and incidence of hiv, hepatitis b virus, and hepatitis c virus infections among males in rhode island prisons. | we evaluated prevalence and intraprison incidence of hiv, hepatitis b virus, and hepatitis c virus infections among male prison inmates. | 2004 | 15226146 |
| highly active antiretroviral therapy and viral response in hiv type 2 infection. | human immunodeficiency virus type 2 (hiv-2), the second human retrovirus known to cause aids, is endemic to west africa but is infrequently found outside this region. we present a case series of 10 hiv-2--infected individuals treated in the united states. physicians applied the principles of highly active antiretroviral therapy (haart), normally used in treating hiv type 1, with modifications considered appropriate for treating hiv-2. cd4+ cell count, hiv-2 virus load, and clinical status were f ... | 2004 | 15227626 |
| identification of a highly divergent hiv type 2 and proposal for a change in hiv type 2 classification. | we report the complete genome sequence of a highly divergent strain of human immunodeficiency virus type 2 (hiv-2), 96fr12034, identified in france from a patient of west african origin. this lineage, h, represents only the third definitive instance of a monkey-to-human transfer of sivsm that has given rise to pathogenic hiv-2. as the different "subtypes" of hiv-2 are analogous to the different groups of hiv-1 we propose that hiv-2 subtypes henceforth by renamed groups in agreement with the hiv ... | 2004 | 15242544 |
| [siv as a source of hiv. on the origin of human immunodeficiency viruses from non-human primates]. | it is assumed that hiv, the human immunodeficiency virus, started its spread after the second world war. molecular analysis of the genome of various hiv-1 types has shown that this virus can be divided into the groups m, n, and o and that these genome sequences fit perfectly to the genomes found in siv of chimpanzees (sivcpz) living in the area of west and central africa. sivcpz is nonpathogenic for chimpanzees indicating that the virus and host have adapted for a long period. hiv-2 genome seque ... | 2004 | 15254823 |
| [seroepidemiological survey of the human immunodeficiency virus, type 2]. | to perform a seroepidemiological study and identify associated factors in a population infected by human immunodeficiency virus, type 2 (hiv-2). a total of 2202 individuals were tested to determine the seroprevalence of this virus. | 2004 | 15941553 |
| an accurate confirmation of human immunodeficiency virus type 1 (hiv-1) and 2 (hiv-2) infections with a dot blot assay using recombinant p24, gp41, gp120 and gp36 antigens. | an immunoblot assay using four recombinant proteins corresponding to human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) gene products was developed to confirm the presence of antibodies to hiv-1 and 2 in sera reactive in screening elisas. serum samples for testing were obtained from healthy seronegative blood donors and from different categories of hiv-infected individuals (asymptomatic hiv-infected, and aids). a positive reaction was defined as reactivity against gag (p24) and at le ... | 2004 | 15912198 |
| evidence for negative selective pressure in hiv-2 evolution in vivo. | hiv-2 sequence divergence and evolution in vivo has not been well characterized so far. to investigate the extent of hiv-2 genetic diversity and better understand how hiv-2 evolves in vivo, env c2-c3 nucleotide sequences were obtained from the plasma and pbmcs virus populations of four hiv-2 patients with different infection periods. phylogenetic analysis showed that three patients were infected with subtype a hiv-2 and the remaining patient was infected with a divergent hiv-2 that could not be ... | 2004 | 15737915 |
| a simple semi-rapid hiv-1&2 confirmatory immunoassay using magnetic particles. | the bionor hiv-1&2 confirmatory test is a semi-rapid simple immunoassay based on magnetic particles for the confirmation of serological status to human immunodeficiency virus (hiv). the specificity and sensitivity of this assay was evaluated by comparison with the diagnostic biotechnology hiv-1 western blot (wb) 2.2 and the hiv-2/sbl-6669 wb. bionor's confirmatory test demonstrated 98% specificity when testing sero-negative blood donors and false positive sera in screening tests compared to 81.5 ... | 2004 | 14667535 |
| enhancement of a human immunodeficiency virus env dna vaccine using a novel polycationic nanoparticle formulation. | in an effort to develop a more effective dna immunization strategy for hiv, we synthesized an hiv-2 env dna vaccine and delivered it in a novel polycationic adjuvant formulation that forms nanoparticles in solution and enhances protein expression. the polycationic adjuvant contained imidazole moieties to facilitate endosomal escape. nanoparticles containing the dna vaccine plasmid were formed by electrostatic condensation with the polycationic adjuvant. we hypothesized that this formulation woul ... | 2003 | 14687705 |
| emergence of the hiv type 1 epidemic in the twentieth century: comparing hypotheses to evidence. | the existence of multiple groups of hiv-1 and hiv-2 suggests that zoonotic transmissions of siv have occurred at a low rate for centuries. hence, an increase in the rate of human-to-human transmission may be necessary and sufficient to explain the emergence of hiv as an epidemic in the twentieth century. three common hypotheses to explain accelerated transmission are (1) social changes accelerated sexual transmission, (2) health care changes accelerated parenteral transmission, and (3) serial pa ... | 2003 | 14709242 |
| comparing modified and plain peptide linked enzyme immunosorbent assay (elisa) for detection of human immunodeficiency virus type-1 (hiv-1) and type-2 (hiv-2) antibodies. | serological diagnosis of human immunodeficiency virus (hiv) based on detection of hiv antibodies is one of the easiest, cheapest and simplest assay. synthetic peptides corresponding to immunodominant regions of envelope glycoprotein (gp41, v3 loop for hiv-1 and gp36 for hiv-2) were used in the present study, to detect the anti-hiv antibodies in sera of sexually transmitted diseases (std), tuberculosis (tb), anti-natal care (anc) patients. about 550 serum samples were tested using enzyme linked i ... | 2003 | 12663143 |
| the cationic amphipathic alpha-helix of hiv-1 viral protein r (vpr) binds to nucleic acids, permeabilizes membranes, and efficiently transfects cells. | viral protein r (vpr) is a small protein of 96 amino acids that is conserved among the lentiviruses human immunodeficiency virus type 1 (hiv-1), hiv-2, and simian immunodeficiency virus. we recently sought to determine whether the karyophilic properties of vpr, as well as its ability to bind nucleic acids, could be used to deliver dna into cells. we have found that the c-terminal domain of vpr-(52-96) is able to efficiently transfect various cell lines. here, we show that the shortest active seq ... | 2003 | 12639957 |
| cross-reaction of anti-simian immunodeficiency virus envelope protein antibodies with human immunoglobulins. | it has been recently established that retroviral envelope proteins (reps) have structural features similar to those of immunoglobulins (igs). in this study, we asked whether anti-rep antibodies cross-react with human igs (higs). to this end, murine monoclonal antibodies (mmoabs) that had been raised against a simian immunodeficiency virus (siv) envelope protein, sivmac251gp120, were screened for their ability to react with human monoclonal igs (hmigs). we show that two hmigs, rfsj2 (a rheumatoid ... | 2003 | 12641652 |
| role of hiv-1 vpr in aids pathogenesis: relevance and implications of intravirion, intracellular and free vpr. | vpr, a 14-kda, 96 amino acid protein, is conserved among the primate lentiviruses hiv-1, hiv-2 and simian immunodeficiency virus supporting the notion that it plays an important role in virus life cycle in vivo. vpr appears to have several functions including cell cycle arrest at g2 stage, apoptosis, nuclear localization, nuclear import of the pre-integration complex, cation selective channel activity and transcriptionally activate hiv-1 ltr and other heterologous promoters. over the years, we h ... | 2003 | 12642033 |
| restriction of multiple divergent retroviruses by lv1 and ref1. | the mouse gene fv1 encodes a saturable restriction factor that selectively blocks infection by n-tropic or b-tropic murine leukemia virus (mlv) strains. despite the absence of an fv1 gene, a similar activity is present in humans that blocks n-mlv infection (ref1). moreover, some non-human primate cell lines express a potentially related inhibitor of hiv-1 and/or sivmac infection (lv1). here, we examine the spectrum of retrovirus-restricting activities expressed by human and african green monkey ... | 2003 | 12554640 |
| cd4-dependent and cd4-independent hiv-2: consequences for neutralization. | hiv-2 is less pathogenic than hiv-1. in contrast to hiv-1, many isolates of hiv-2, including primary isolates, can infect cells independently of cd4. | 2003 | 12556682 |
| expression patterns of phenotypic markers on lymphocytes from human immunodeficiency virus type 2-infected baboons. | the development of aids in hiv-1-infected humans is associated with profound changes in the expression patterns of lymphocyte phenotypic markers associated with increased immune activation and with decreased recall immune responses. in assessing these immunologic changes in an animal model, we characterized the expression patterns of immune activation markers on lymphocyte subsets during the acute, chronic, and end stages of hiv-2 infection in baboons. using flow cytometry, we identified 21 huma ... | 2003 | 12581514 |
| comparison of hiv-1 and hiv-2 infectivity from a prospective cohort study in senegal. | from a prospective cohort study of 1948 initially human immunodeficiency virus (hiv) uninfected female commercial sex workers followed between 1985 and 1999 in dakar, senegal, the authors compared the male to female per infectious sexual exposure transmission probability of hiv types one (hiv-1) and two (hiv-2). new non-parametric competing risks failure time methods were used, which minimized modelling assumptions and controlled for risk factors for hiv infection. the hiv-1 versus hiv-2 infecti ... | 2003 | 12590415 |
| budding and secretion of hiv gag-env virus-like particles from recombinant human adenovirus infected cells. | we have characterized the assembly, budding and extra-cellular release of human immunodeficiency virus (hiv) gag-env virus-like particles (vlps) from human embryonic kidney cells (293 cells expressing the e1a protein of adenovirus) infected with recombinant replication-defective human adenovirus type 5. recombinant human adenovirus vectors expressing the chimeric gag-env protein were constructed by inserting the gag-env fusion gene into the e1a region of the human adenovirus type 5. biochemical ... | 2003 | 12606078 |
| molecular investigation of gb virus c rna in hemodialysis and thalassemics patients from brazil. | the gb virus c (gbv-c)/hepatitis g virus (hgv) is a member of the flaviviridae family. based on the clinical and epidemiological profiles, this virus could be acquired mainly by parenteral transmission through contaminated blood. we therefore investigated the presence of gbv-c/hgv and its relation with the other blood borne viruses as hepatitis b and c viruses (hbv, hcv) in hemodialysis and thalassemic individuals and blood donors from ribeirão preto-brazil. detection of blood borne virus marker ... | 2003 | 12617334 |
| virus inactivation in bone tissue transplants (femoral heads) by moist heat with the 'marburg bone bank system'. | several virus inactivation procedures like heat treatment, gamma irradiation and chemical sterilization are used to increase the safety of bone tissue transplants. in this study we present data on the virus-inactivating effect of heat disinfection on human femoral heads, using the marburg bone bank system 'lobator sd-2'. three enveloped viruses (human immunodeficiency virus type 2 [hiv-2], bovine viral diarrhoea virus as a model for hepatitis c virus [hcv], and the herpesvirus pseudorabies virus ... | 2003 | 12623062 |
| identification of gp120 binding sites on cxcr4 by using cd4-independent human immunodeficiency virus type 2 env proteins. | human immunodeficiency virus (hiv) and simian (siv) immunodeficiency virus entry is mediated by binding of the viral envelope glycoprotein (env) to cd4 and chemokine receptors, ccr5 and/or cxcr4. cd4 induces extensive conformational changes that expose and/or induce formation of a chemokine receptor binding site on gp120. cd4-independent env's of hiv type 1 (hiv-1), hiv-2, and siv have been identified that exhibit exposed chemokine receptor binding sites and can bind directly to ccr5 or cxcr4 in ... | 2003 | 12502809 |
| actinomycin d induces high-level resistance to thymidine analogs in replication of human immunodeficiency virus type 1 by interfering with host cell thymidine kinase expression. | actinomycin d (actd) is a transcription inhibitor and has been used in the treatment of certain forms of cancer. actd has been reported to be a potential inhibitor of human immunodeficiency virus type 1 (hiv-1) replication due to its ability to inhibit reverse transcription. in contrast to what was expected, low concentrations of actd (1 to 10 nm) upregulated hiv-1 replication 8- to 10-fold in mt-2 cells and had no effect on hiv-2 replication or on hiv-1 replication in mt-4, jurkat, or periphera ... | 2003 | 12502817 |
| x-ray absorption spectroscopic studies of zinc in the n-terminal domain of hiv-2 integrase and model compounds. | x-ray absorption spectroscopy (xas), including extended x-ray absorption fine structure (exafs) and x-ray absorption near-edge structure (xanes) analysis, has been carried out at the zn k edge of the n-terminal part of the integrase protein of the human immunodeficiency virus, type 2 (hiv-2), and of some zinc coordination compounds. in the presence of excess beta-mercaptoethanol, which was present in the nmr structure elucidation of the protein [eijkelenboom et al. (1997), curr. biol. 7, 739-746 ... | 2003 | 12511797 |
| introduction of human immunodeficiency virus type 2 infection in the philippines. | the aim of this study was to describe and document the first case of human immunodeficiency virus type 2 (hiv-2) in the philippines by using serological and molecular techniques and to compare the diversity of this strain to that of strains from other countries. with the introduction of hiv-2 into the country and the presence of diversified strains of hiv-1, the use of highly sensitive assays to detect all these strains is recommended. | 2003 | 12517912 |
| increased virus replication and virulence after serial passage of human immunodeficiency virus type 2 in baboons. | similar to human immunodeficiency virus type 1 (hiv-1) infection of humans, the natural history of hiv-2 infection in baboons (papio cynocephalus) is a slow and chronic disease that generally takes several years before an aids-like condition develops. to shorten the amount of time to the development of disease, we performed five serial passages of hiv-2(uc2) in baboons by using blood and bone marrow samples during the acute phase of infection when viral loads were at high levels. after these ser ... | 2003 | 12477812 |
| a structurally disordered region at the c terminus of capsid plays essential roles in multimerization and membrane binding of the gag protein of human immunodeficiency virus type 1. | crystal structures of human immunodeficiency virus type 1 (hiv-1) capsid protein (ca) reveal that the last 11 c-terminal amino acids are disordered. this disordered region contains a glycine-rich sequence 353-gvggp-357 (numbering refers to the initiation methionine of gag) that is highly conserved within the gag proteins of hiv-1, hiv-2, and simian immunodeficiency virus, which suggests the importance of this sequence in virus replication. in the present study, we demonstrate that changing any i ... | 2003 | 12525611 |
| noninvasive detection of new simian immunodeficiency virus lineages in captive sooty mangabeys: ability to amplify virion rna from fecal samples correlates with viral load in plasma. | the sooty mangabey (sm) (cercocebus atys) is the natural host of a simian immunodeficiency virus, termed sivsm, which gave rise to human immunodeficiency virus type 2. data on the geographic distribution, prevalence, and genetic diversity of sivsm in the wild remains limited. to address this issue, noninvasive strategies based on screening sm fecal and urine specimens for sivsm-specific antibodies and virion rna (vrna) were developed, and the results were correlated with viral loads in plasma. t ... | 2003 | 12525656 |
| characterization of a novel rna-binding region of eif4gi critical for ribosomal scanning. | the eukaryotic translation initiation factor eif4gi binds several proteins and acts as a scaffold to promote preinitiation complex formation on the mrna molecule (48s). following mrna attachment this complex scans along the messenger in a 5' to 3' direction until it locates and recognizes the initiation start codon. by using a combination of retroviral and picornaviral proteases (hiv-2 and l respectively) in the reticulocyte lysate system, we have characterized a 40 amino acid (aa) region of eif ... | 2003 | 12682023 |
| performance characteristics of the trugene hiv-1 genotyping kit and the opengene dna sequencing system. | the trugene hiv-1 genotyping kit and opengene dna sequencing system are designed to sequence the protease (pr)- and reverse transcriptase (rt)-coding regions of human immunodeficiency virus type 1 (hiv-1) pol. studies were undertaken to determine the accuracy of this assay system in detecting resistance-associated mutations and to determine the effects of rna extraction methods, anticoagulants, specimen handling, and potentially interfering substances. samples were plasma obtained from hiv-infec ... | 2003 | 12682150 |
| susceptibility of hvs-immortalized lymphocytic hsc-f cells to various strains and mutants of hiv/siv. | susceptibility of hsc-f, a cynomolgus macaque cell line immortalized by herpesvirus saimiri, to infection with various primate immunodeficiency viruses were monitored. while nl432 clone of human immunodeficiency virus type 1 (hiv-1) did not grow at all in hsc-f cells, gh123 and gl-an clones of hiv-2, and ma239 clone of simian immunodeficiency virus isolated from macaque monkeys (sivmac) did grow in these cells. in addition, nm-3 clone of a chimeric simian and human immunodeficiency virus (shiv) ... | 2003 | 12684704 |
| natural variation of the nef gene in human immunodeficiency virus type 2 infections in portugal. | human immunodeficiency virus type 2 (hiv-2) infections cause severe immunodeficiency in humans, although hiv-2 is associated frequently with reduced virulence and pathogenicity compared to hiv-1. genetic determinants that play a role in hiv pathogenesis are relatively poorly understood but nef has been implicated in inducing a more pathogenic phenotype in vivo. however, relatively little is known about the role of nef in hiv-2 pathogenesis. to address this, the genetic composition of 44 nef alle ... | 2003 | 12692296 |
| serum immunoglobulin a (iga)-mediated immunity in human immunodeficiency virus type 2 (hiv-2) infection. | in the present study, we sought to define the importance of serum iga (siga)-mediated immunity in hiv-2 infection. serum samples from a total of 29 hiv-2-infected patients from guinea-bissau (n = 20) and portugal (n = 9) were studied. samples from seronegative individuals were used as controls. antibody reactivity to native and recombinant envelope glycoproteins as well as peptides representing various regions of the envelope glycoproteins was investigated. furthermore, the capacity of purified ... | 2003 | 12706073 |
| comparative in vitro effects of azt and extracts of ocimum gratissimum, ficus polita, clausena anisata, alchornea cordifolia, and elaeophorbia drupifera against hiv-1 and hiv-2 infections. | the effects of ocimum gratissimum (ghx-2), ficus polita (ghx-6), clausena anisata (ghx-7), alchornea cordifolia (ghx-26), elaeophorbia drupifera (ghx-27), and azt on in vitro hiv-1 and hiv-2 replication and cytopathicity were compared. all plant extracts inhibited hiv-1 strain htlviii(b) cytopathicity, the leaves of ghx-2 and the seeds of ghx-26 having high antiviral indices (110 and 90, respectively). against hiv-2 strain gh1, the ec(50) values ranged from <0.005 to 0.075 mg/ml when treatment w ... | 2003 | 12719004 |
| specific g2 arrest of caprine cells infected with a caprine arthritis encephalitis virus expressing vpr and vpx genes from simian immunodeficiency virus. | primate lentivirus (hiv and siv) vpr accessory genes encode 12- to 14-kda proteins which induce cell cycle arrest at the g2 phase of infected cells, preventing them from going through mitosis. members of the hiv-2/sivmac/sivsmm group also encode a second closely related accessory protein called vpx. vpx and hiv vpr are critical for virus replication in nondividing cells due to their participation in nuclear import of the preintegration complex. caprine arthritis encephalitis virus (caev) and mae ... | 2003 | 12726725 |
| naturally occurring amino acid substitutions in the hiv-2 rod envelope glycoprotein regulate its ability to augment viral particle release. | the envelope glycoprotein of hiv-2 rod10 has the intriguing ability to enhance the rate of viral particle release from infected cells. however, not all hiv-2 envelope glycoproteins are active in this regard. indeed, we have previously noted that, despite a high degree of identity with that of rod10, the envelope protein of the rod14 isolate was unable to enhance virus production. in this study, site-directed mutagenesis was employed to reveal that a single naturally occurring alanine-to-threonin ... | 2003 | 12726729 |
| vpx and vpr proteins of hiv-2 up-regulate the viral infectivity by a distinct mechanism in lymphocytic cells. | mutants of human immunodeficiency virus type 2 (hiv-2) carrying a frame-shift mutation in vpx, vpr, and in both genes were monitored for their growth potentials in a newly established lymphocytic cell line, hsc-f. worthy of note, the replication of a vpx single mutant, but not vpr, was severely impaired in these cells, and that of a vpx-vpr double mutant was more damaged. defective replication sites of the vpx single and vpx-vpr double mutants were demonstrated to be mapped, respectively, to the ... | 2003 | 12737994 |
| identification of a subset of human immunodeficiency virus type 1 (hiv-1), hiv-2, and simian immunodeficiency virus strains able to exploit an alternative coreceptor on untransformed human brain and lymphoid cells. | the chemokine receptors ccr5 and cxcr4 are the major coreceptors for human immunodeficiency virus (hiv) and simian immunodeficiency virus (siv). at least 12 other chemokine receptors or close relatives support infection by particular hiv and siv strains on cd4(+) transformed indicator cell lines in vitro. however, the role of these alternative coreceptors in vivo is presently thought to be insignificant. infection of cell lines expressing high levels of recombinant cd4 and coreceptors thus does ... | 2003 | 12743271 |
| hemophilia care in the state of rio de janeiro, brazil. | in the developing countries of the world, few people with hemophilia receive adequate care. nevertheless, brazil has made significant advances in the treatment of hemophilia over the last decade. the provision of factor concentrates imported by the government of brazil is gradually increasing, and patients receive the concentrates for free. a national register was established as well as a coordinated program for comprehensive care. of the 6 297 persons with hemophilia in brazil who were register ... | 2003 | 12744788 |
| a retrospective clinical, laboratory and outcome analysis in 43 cases of acute aseptic meningitis. | forty-three consecutive cases of acute aseptic meningitis (aam) presenting within a 24-months period were retrospectively analysed with respect to clinical symptomatology, cerebrospinal fluid (csf) findings, clinical course, treatment and outcome. nineteen of the 43 aam cases (44%) were caused by enterovirus, one by hiv (2%), two by varicella zoster virus (5%), three due to herpes simplex virus i (7%), two due to herpes simplex virus ii (5%), one due to central european encephalitis virus (2%), ... | 2003 | 12752401 |
| antiretroviral activity of semisynthetic derivatives of glycopeptide antibiotics. | a variety of semisynthetic derivatives of natural antibacterial glycopeptide antibiotics such as vancomycin, eremomycin, ristocetin a, teicoplanin a(2)-2, da-40926, their aglycons, and also the products of their partial degradation with a destroyed or modified peptide core show marked anti-retroviral activity in cell culture. in particular, aglycon antibiotic derivatives containing various substituents of a preferably hydrophobic nature displayed activity against human immunodeficiency virus typ ... | 2003 | 12801238 |
| evolution and diversity of hiv-1 in africa--a review. | the hiv/aids pandemic represents a major development crisis for the african continent, which is the worst affected region in the world. currently, almost 30 of the 42 million people infected with hiv worldwide live in africa. aids in humans is caused by two lentiviruses, hiv-1 and hiv-2, which entered the human population by zoonotic transmissions from at least two different african primate species. extensive phylogenetic analyses of partial and full-length genome sequences have helped to gain i ... | 2003 | 12803467 |
| infection with hepatitis b and c viruses and human retroviruses (htlv-i and hiv) among high-risk lebanese patients. | three groups of lebanese patients (haemophiliacs, patients on cycled cancer chemotherapy who were regularly receiving blood transfusions, and intravenous drug users) and a control group of healthy blood donors were checked for markers of infection with hepatitis viruses (b and c) and human retroviruses (hiv and htlv-i). compared with the controls, all three groups of patients were more likely to be seropositive for antibody to hepatitis c virus (anti-hcv), and the haemophiliacs and cancer patien ... | 2003 | 12803874 |
| human immunodeficiency virus type 2 reverse transcriptase activity in model systems that mimic steps in reverse transcription. | human immunodeficiency virus type 2 (hiv-2) infection is a serious problem in west africa and asia. however, there have been relatively few studies of hiv-2 reverse transcriptase (rt), a potential target for antiviral therapy. detailed knowledge of hiv-2 rt activities is critical for development of specific high-throughput screening assays of potential inhibitors. here, we have conducted a systematic evaluation of hiv-2 rt function, using assays that model specific steps in reverse transcription ... | 2003 | 12805462 |
| diagnosis, antiretroviral therapy, and emergence of resistance to antiretroviral agents in hiv-2 infection: a review. | human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) are the causative agents of aids. hiv-2 is prevalent at moderate to high rates in west african countries, such as senegal, guinea, gambia, and cape verde. diagnosis of hiv-2 is made with a positive hiv-1/hiv-2 elisa or simple/rapid assay, followed by one or two confirmatory tests specific for hiv-2. following cd(4)(+)t cell counts, hiv-2 viral burden and clinical signs and symptoms of immunodeficiency are beneficial in monitoring hiv ... | 2003 | 12807687 |
| mechanisms of cd4+ t lymphocyte cell death in human immunodeficiency virus infection and aids. | aids, caused by the retroviruses human immunodeficiency virus type 1 and type 2 (hiv-1 and hiv-2), has reached pandemic proportions. therefore, it is critical to understand how hiv causes aids so that appropriate therapies can be formulated. primarily, hiv infects and kills cd4(+) t lymphocytes, which function as regulators and amplifiers of the immune response. in the absence of effective anti-retroviral therapy, the hallmark decrease in cd4(+) t lymphocytes during aids results in a weakened im ... | 2003 | 12810858 |
| viral reservoirs/transient infection in hiv/aids: where are we now and where should we go? summary of the june 13-14, 2002 think tank meeting. | highly active antiretroviral therapy in individuals infected with human immunodeficiency virus (hiv) often lowers serum levels of virus to below current detection limits. however, cessation of therapy results in there appearance of virus replication, indicating that hiv-infected cells persist in such individuals. identification, and elimination, of such reservoirs of virus-infected cells are crucial for eradicating hiv from infected individuals. more research studies are needed to devise strateg ... | 2003 | 12816085 |
| greater cd8+ tcr heterogeneity and functional flexibility in hiv-2 compared to hiv-1 infection. | virus-specific cd8(+) t cells are known to play an important role in the control of hiv infection. in this study we investigated whether there may be qualitative differences in the cd8(+) t cell response in hiv-1- and hiv-2-infected individuals that contribute to the relatively efficient control of the latter infection. a molecular comparison of global tcr heterogeneity showed a more oligoclonal pattern of cd8 cells in hiv-1- than hiv-2-infected patients. this was reflected in restricted and con ... | 2003 | 12817012 |
| identification of the nuclear localization signal of human immunodeficiency virus type 2 vpx. | the vpx protein of human immunodeficiency virus type 2 (hiv-2) is a viral accessory protein related to, but distinct from, the vpr protein of hiv-1. vpx is packaged into virions and, as a component of the viral preintegration complex (pic), vpx is required for efficient virus replication in nondividing cells. therefore, the localization of vpx in cells is dynamic and dependent upon discrete domains of the protein. expressed in the absence of other viral proteins, vpx localizes to the nucleus of ... | 2003 | 12832198 |
| clinical progression in early and late stages of disease in a cohort of individuals infected with human immunodeficiency virus-2 in guinea-bissau. | the aim of this study was to assess the rate of clinical progression to early and late stages of human immunodeficiency virus-2 (hiv-2) infection. cd4 cell counts and other potential prognostic markers for disease progression were also evaluated. in january 1990 an open prospective cohort of police officers in guinea-bissau was initiated with yearly serological and clinical follow-up. follow-up ended in june 1998. symptoms were classified according to the world health organization staging system ... | 2003 | 12839157 |
| whole-blood agglutination assay for on-site detection of human immunodeficiency virus infection. | simple and rapid diagnostic tests are needed to curtail human immunodeficiency virus (hiv) infection, especially in the developing and underdeveloped nations of the world. the visible-agglutination assay for the detection of hiv with the naked eye (neva hiv, which represents naked eye visible-agglutination assay for hiv) is a hemagglutination-based test for the detection of antibodies to hiv in whole blood. the neva hiv reagent is a cocktail of highly stable recombinant bifunctional antibody fus ... | 2003 | 12843006 |
| polymorphism of human and primate rantes, cx3cr1, ccr2 and cxcr4 genes with regard to hiv/siv infection. | among genes that influence human susceptibility to hiv (human immunodeficiency virus) infection or aids (acquired immunodeficiency syndrome) progression, chemokine-receptor and chemokine genes were extensively studied because of their role as hiv co-receptors or co-receptor competitors, respectively. we have studied in non-human primates (chimpanzee, gorilla, gibbon, orang-utan, crab-eating and rhesus macaque, baboon and marmoset) the rantes, ccr2 and cx3cr1 gene sequences in regions surrounding ... | 2003 | 12879309 |
| increased risk of high-grade cervical squamous intraepithelial lesions and invasive cervical cancer among african women with human immunodeficiency virus type 1 and 2 infections. | to assess the risk of prevalent high-grade cervical squamous intraepithelial lesions (hsils) or invasive cervical cancer (icc) associated with human immunodeficiency virus (hiv) type 1, hiv-2, and human papillomavirus (hpv) infections, hiv load, and cd4 cell count, we studied 4119 women attending an outpatient clinic in senegal. hiv infection was associated with increased rates of cervical infection with high-risk hpvs. among women infected with high-risk hpvs, those with hiv-1 (odds ratio [or], ... | 2003 | 12898443 |
| pol gene sequence variation in swedish hiv-2 patients failing antiretroviral therapy. | there is limited knowledge about how to treat and interpret results from genotypic resistance assays in hiv-2 infection. here, genetic variation in hiv-2 pol gene was studied in 20 of 23 known hiv-2 cases in sweden. five patients with signs of virological treatment failure were longitudinally studied. clinical, virological and immunological data were collected and the protease (pr) and first half of the reverse transcriptase (rt) was amplified and directly sequenced from plasma samples. moderate ... | 2003 | 12908931 |
| the packaging signal of simian immunodeficiency virus is upstream of the major splice donor at a distance from the rna cap site similar to that of human immunodeficiency virus types 1 and 2. | deletion mutation of the rna 5' leader sequence of simian immunodeficiency virus (siv) was used to localize the virus packaging signal. deletion of sequences upstream of the major splice donor (sd) site produced a phenotype most consistent with a packaging defect when analysed by both rnase protection assay and rt-pcr. sequences downstream of the sd were deleted and produced varying effects but did not affect packaging: a large downstream deletion had little effect on function, whereas a nested ... | 2003 | 12917463 |
| male circumcision for prevention of heterosexual acquisition of hiv in men. | the findings from observational studies, reviews and meta-analyses, supported by biological theories, that circumcised men appear less likely to acquire human immunodeficiency virus (hiv) has contributed to the recent ground swell of support for considering male circumcision as a strategy for preventing sexually acquired infection. we sought to elucidate and appraise the global evidence from published and unpublished studies that circumcision can be used as an intervention to prevent hiv infecti ... | 2003 | 12917962 |
| cyanovirin-n gel as a topical microbicide prevents rectal transmission of shiv89.6p in macaques. | cyanovirin-n (cv-n), an 11-kda cyanobacterial protein, potently inactivates diverse strains of hiv-1, hiv-2, and simian immunodeficiency virus (siv) and also prevents virus-to-cell fusion, virus entry, and infection of cells in vitro. these properties make cv-n an attractive candidate for use as a topical microbicide to prevent the sexual transmission of hiv. we evaluated the efficacy of gel-formulated, recombinant cv-n gel asa topical microbicide in male macaques (macaca fascicularis) that were ... | 2003 | 12921090 |
| reduction of the diagnostic window in three cases of human immunodeficiency-1 subtype e primary infection with fourth-generation hiv screening assays. | the influence of genetic variability on the sensitivity of serological diagnosis of human immunodeficiency virus (hiv) infection has, to date, been poorly investigated. the aim of the present study was to assess whether fourth-generation assays for the combined detection of hiv antigen and antibodies to hiv (anti-hiv) permit a reduction of the diagnostic window in comparison to third-generation antibody enzyme immunoassays (eias), which so far have shown a poor sensitivity for detection of hiv-1 ... | 2003 | 12925157 |
| a non-canonical transferable signal mediates nuclear import of simian immunodeficiency virus vpx protein. | protein transport into the nucleus is generally considered to involve specific nuclear localization signals (nls) though it is becoming increasingly evident that efficient and well controlled import of proteins which lack a canonical nls also occurs in cells. vpx, a 112 amino acid protein from human immunodeficiency virus type 2 (hiv-2) and the closely related simian immunodeficiency virus (siv) is one such protein, which does not have an identifiable canonical nls and is yet efficiently importe ... | 2003 | 12927548 |
| a small molecule hiv-1 inhibitor that targets the hiv-1 envelope and inhibits cd4 receptor binding. | bms-378806 is a recently discovered small molecule hiv-1 inhibitor that blocks viral entrance to cells. the compound exhibits potent inhibitory activity against a panel of r5-(virus using the ccr5 coreceptor), x4-(virus using the cxcr4 coreceptor), and r5/x4 hiv-1 laboratory and clinical isolates of the b subtype (median ec50 of 0.04 microm) in culture assays. bms-378806 is selective for hiv-1 and inactive against hiv-2, siv and a panel of other viruses, and exhibits no significant cytotoxicity ... | 2003 | 12930892 |
| inhibition of human immunodeficiency virus by a new class of pyridine oxide derivatives. | a new class of pyridine oxide derivatives as inhibitors of human immunodeficiency virus type 1 (hiv-1) and/or hiv-2 replication in cell culture has been identified. the compounds, which specifically inhibit hiv-1, behave as typical nonnucleoside reverse transcriptase inhibitors (nnrtis). the most active congener of this group, jpl-133 (uc-b3096), has a 50% effective concentration of 0.05 microg/ml for hiv-1(iii(b)) with a selectivity index of approximately 760 in cem cell cultures. however, the ... | 2003 | 12937000 |
| identification and characterization of hiv-2 strains obtained from asymptomatic patients that do not use ccr5 or cxcr4 coreceptors. | in vivo, human immunodeficiency virus type 2 (hiv-2) infection reveals several unique characteristics when compared to hiv-1 infection, the most remarkable of which is the extraordinarily long asymptomatic period. here we describe two hiv-2 primary isolates, obtained from asymptomatic individuals, which do not infect any coreceptor-expressing cell lines tested. in those cells, we show that the absence of replication is directly related to cell entry events. furthermore, productive infection obse ... | 2003 | 12951028 |
| down-modulation of mature major histocompatibility complex class ii and up-regulation of invariant chain cell surface expression are well-conserved functions of human and simian immunodeficiency virus nef alleles. | recently, it has been demonstrated that the human immunodeficiency virus type 1 (hiv-1) nef from laboratory strains down-modulates cell surface expression of mature major histocompatibility complex class ii (mhc-ii) molecules, while up-regulating surface expression of the invariant chain (ii) associated with immature mhc-ii (p. stumptner-cuvelette, s. morchoisne, m. dugast, s. le gall, g. raposo, o. schwartz, and p. benaroch, proc. natl. acad. sci. usa 98:12144-12149, 2001). these nef functions ... | 2003 | 12970439 |
| hepatitis b and c virus infections in the immune compromised. | this review compares and contrasts the natural history and treatment of hepatitis b and c virus infections in three principal populations of immune compromised individuals: (1) patients co-infected with hiv; (2) patients with liver failure secondary to hepatitis b or c virus infection who undergo liver transplantation, and (3) patients with hepatitis b or c virus infection who undergo anticancer chemotherapy. | 2003 | 14502001 |
| novel human immunodeficiency virus (hiv) inhibitors that have a dual mode of anti-hiv action. | we have found that novel pyridine oxide derivatives are inhibitors of a wide range of human immunodeficiency virus (hiv) type 1 (hiv-1) and hiv-2 strains in cem cell cultures. some of the compounds showed inhibitory activities against recombinant hiv-1 reverse transcriptase (rt), whereas others were totally inactive against this viral protein in vitro. partial retention of anti-hiv-1 activity against virus strains that contain a variety of mutations characteristic of those for resistance to nonn ... | 2003 | 14506017 |