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replicative capacity of hiv-2, like hiv-1, correlates with severity of immunodeficiency.we have obtained 15 hiv-2 isolates from the peripheral blood mononuclear cells (pbmcs) of 24 hiv-2-infected west african people. the frequency of virus isolation correlated with the severity of hiv-2 infection; only three isolates were obtained from 11 asymptomatic individuals, whereas virus was isolated from nearly all (12 of 13) individuals with symptoms. the hiv-2 isolates showed distinct replicative and cytopathic characteristics and, similarly to hiv-1 isolates, could be divided into two ma ...19902190603
envelope cross-reactivity between human immunodeficiency virus types 1 and 2 detected by different serological methods: correlation between cross-neutralization and reactivity against the main neutralizing site.a total of 70 human immunodeficiency virus type 1 (hiv-1) and 42 hiv-2 antibody-positive serum samples, collected from groups of individuals in which only one type of hiv prevails, were tested for cross-reactivity against hiv-2 and hiv-1 proteins by western blot (wb) (immunoblot), radioimmunoprecipitation assay (ripa), neutralization analysis, and enzyme-linked immunosorbent assay with as antigen synthetic peptides representing selected parts of the envelope (env) glycoproteins. cross-reactions ...19902191152
interference patterns of human immunodeficiency viruses hiv-1 and hiv-2.the ability of cells infected with a retrovirus to interfere with superinfection by another retrovirus usually involves blockage, by the primary virus, of the receptors for the superinfecting virus. retroviruses using different receptors do not interfere with each other, and this property has been used to classify various types of retroviruses. different isolates of human immunodeficiency virus (hiv) were subjected to this type of analysis, and it was found that all hiv-1s cross-interfere with e ...19902191494
comparison of commercial kits for the detection of antibody to human immunodeficiency virus type 1 (hiv-1) in nigeria.four commercial kits for the detection of antibodies to hiv-1 were compared with regard to their sensitivity, specificity and positive predictive value. the wellcozyme competitive enzyme immunoassay was the least sensitive (62.5%), while roche eia, was the most sensitive (100%). all the commercial kits gave false negative results except the roche eia system. the serodia particle agglutination test had the least positive predictive value of 26.9% while roche eia had the highest (88.9%). our resul ...19902191859
neuropathology of the acquired immunodeficiency syndrome.this review attempts to assess critically the literature on the neuropathology of acquired immunodeficiency syndrome in light of our experience with 172 patients with acquired immunodeficiency syndrome who underwent extensive postmortem examinations of the central and peripheral nervous systems. the neuropathologic manifestations of the disease can be divided into three categories: (1) primary or putative/indirect effects of the human immunodeficiency virus, (2) opportunistic infections, and (3) ...19902194443
recombinant hiv2 protease processes hiv1 pr53gag and analogous junction peptides in vitro.a synthetic dna fragment encoding a protease precursor of the human immunodeficiency virus type 2 (hiv2) was cloned and expressed in bacteria and yeast. a recombinant plasmid encoding a hybrid polypeptide consisting of human superoxide dismutase and an hiv2 protease precursor of 113 amino acids was constructed for regulated intracellular expression in bacteria. induction of this plasmid produced an autoprocessed form of the retroviral enzyme possessing the correct molecular weight. overexpressio ...19902199446
specific tropism of hiv-1 for microglial cells in primary human brain cultures.human immunodeficiency virus (hiv) frequently causes neurological dysfunction and is abundantly expressed in the central nervous system (cns) of acquired immunodeficiency syndrome (aids) patients with hiv encephalitis or myelopathy. the virus is found mostly in cells of the monocyte-macrophage lineage within the cns, but the possibility of infection of other glial cells has been raised. therefore, the effects of different hiv-1 and hiv-2 strains were studied in primary cultures of adult human br ...19902200125
titration of human immunodeficiency virus type 1 (hiv-1) and quantitative analysis of virus expression in vitro using liquid rna-rna hybridization.an assay is described for titration of human immunodeficiency virus type 1 (hiv-1) and for quantitative analysis of virus expression in vitro. the assay utilizes a liquid rna-rna hybridization method coupled with reversible target capture (rtc) on oligo(dt) derivatized magnetic particles. the assay provides a rapid, specific, and sensitive method for quantitation of hiv-1 rna molecules present either in cells or in viral particles from cell-free culture media. chronically infected monocytoid u1. ...19902200801
function of the human immunodeficiency virus types 1 and 2 rev proteins is dependent on their ability to interact with a structured region present in env gene mrna.the interaction of the human immunodeficiency virus type 1 (hiv-1) rev protein with a structured region in env mrna (the rev-responsive element [rre]) mediates the export of structural mrnas from the nucleus to the cytoplasm. we demonstrated that unlike hiv-1 rev, which functions with both the hiv-1 and hiv-2 rres, hiv-2 rev functions only with the hiv-2 rre. rev-rre binding studies suggested that the lack of nonreciprocal complementation stems from the inability of hiv-2 rev to interact with hi ...19902200888
the epidemiology of sexually transmitted diseases in africa and latin america.we review some aspects of the epidemiology of sexually transmitted diseases (stds) in the developing countries of africa and latin america. apart from their elevated prevalence, they are responsible for important morbidity in mother and child. stillbirth, premature delivery, conjunctivitis, and respiratory tract morbidity of the neonate are frequently caused by stds. sequelae in adult women include pelvic inflammatory disease, ectopic pregnancy, and infertility. the emergence of antimicrobial re ...19902202406
current status of clinical laboratory tests for the human immunodeficiency virus.the predictive values of positive and negative test results for human immunodeficiency virus (hiv) antibody are extremely high in laboratories that have good quality control and high performance standards and use licensed fda-approved enzyme immunoassay (eia) and western blot standardized tests. with a carefully designed protocol, the false-positive rate of combined eia and western blot has been reported to be as low as 1 in 10(5). when results of hiv confirmatory antibody tests are indeterminat ...19902202798
structure-based design of nonpeptide inhibitors specific for the human immunodeficiency virus 1 protease.by using a structure-based computer-assisted search, we have found a butyrophenone derivative that is a selective inhibitor of the human immunodeficiency virus 1 (hiv-1) protease. the computer program creates a negative image of the active site cavity using the crystal structure of the hiv-1 protease. this image was compared for steric complementarity with 10,000 molecules of the cambridge crystallographic database. one of the most interesting candidates identified was bromperidol. haloperidol, ...19902204060
competitive enzyme-immunoassays using native viral antigens to discriminate between hiv-1 and hiv-2 infections.human immunodeficiency virus (hiv) strains can be separated into two serotypes: hiv-1 and hiv-2. in the study reported herein, we developed and evaluated competitive enzyme-immunoassays (ceia-1 for the detection of antibody to hiv-1, ceia-2 for the detection of antibody to hiv-2) to discriminate serologically between hiv-1 and hiv-2 infections. in most of the cases, the serotyping of known reactive serum samples was done easily with the ceias, showing a similar specificity to the western blot. s ...19902211958
an inhibitor of the protease blocks maturation of human and simian immunodeficiency viruses and spread of infection.the activity of the human immunodeficiency virus (hiv) protease is essential for processing of the gag-pol precursor proteins and maturation of infectious virions. we have prepared a peptidomimetic inhibitor, u-75875, that inhibited hiv-1 gag-pol protein processing in an essentially irreversible manner. noninfectious virus particles produced in the presence of the drug contained gag precursors and were morphologically immature. in human peripheral blood mononuclear cells and in a continuous cell ...19902217178
effect of two novel inhibitors of the human immunodeficiency virus protease on the maturation of the hiv gag and gag-pol polyproteins.the ability of two novel synthetic compounds to inhibit the hiv protease-mediated processing of hiv-1 precursor polyproteins was investigated in an in vitro gag-protease mixed lysate assay system and in an assay using recombinant baculoviruses engineered to express the hiv-1 gag and pol genes in cultured insect cells. with the in vitro mixed lysate assay we have shown that both compounds at 1 microm can completely inhibit the hiv-1 and hiv-2 protease-mediated release of p24 from the hiv-1 gag pr ...19902219737
[the human immunodeficiency virus type 2]. 19902219846
[a radioimmunoprecipitation method in the serodiagnosis of hiv infection: the development of the optimal conditions for its performance and the evaluation of the possibilities for its use].the optimum conditions for using the method of radioimmunoprecipitation (rip) for the detection of human immunodeficiency virus (hiv) in serum samples have been established. out of several available cell lines persistently infected with hiv, specially selected line 17 has been chosen. the characteristic feature of this is the high and stable (under the conditions of prolonged cultivation) accumulation of virus-specific proteins in infected cells. the optimum conditions for making the test and it ...19902220217
the polymerase chain reaction in the human immunodeficiency virus diagnosis.the pcr technique detects hiv1 and hiv2 dna and rna sequences in mononuclear cells with high sensitivity. it allows therefore to analyse the mother to child hiv1 transmission. moreover, in the near future, the quantification of the pcr products could allow the follow-up of the patients treated for hiv infection.19902221502
evaluation of a line immunoassay for the differential detection of antibodies to human immunodeficiency virus.a newly introduced single strip line immunoassay was evaluated as a possible alternative to western blot for the differential detection of antibodies to multiple hiv-1 and hiv-2 antigens in human serum. in a panel of 153 sera found to be positive twice in currently used screening tests, the line immunoassay and the western blot detected 44 true positive results. using western blot as reference method, the line immunoassay gave 100% specificity and sensitivity. these results suggest that the line ...19902226497
immunoprecipitation of human immunodeficiency virus type 2 glycoproteins by sera positive for human immunodeficiency virus type 1.analysis by radioimmunoprecipitation of serum samples from 27 different human immunodeficiency virus type 1 (hiv-1)-infected individuals residing in chile showed that the sera of 26% of these individuals also react with glycoprotein gp125 of hiv type 2 (hiv-2). this cross-reaction seems to reflect a qualitative difference among infected individuals, because the titer of antibodies against gp120 of hiv-1 in the cross-reacting samples did not differ significantly from that in the non-cross-reactin ...19902229392
mutational analysis of simian immunodeficiency virus from african green monkeys and human immunodeficiency virus type 2.we constructed ten mutants of simian immunodeficiency virus isolated from african green monkey (sivagm), and nine mutants of human immunodeficiency virus type 2 (hiv-2) in vitro. their infectivity, cytopathogenicity, transactivation potential, virus rna, and protein synthesis were examined by transfection and infection experiments. mutations in three structural (gag, pol, env) and two regulator (tat, rev) genes abolished the infectivity of both viruses, but vpx, vpr (hiv-2), and nef were dispens ...19902231682
the human immunodeficiency virus type 2 vpr gene is essential for productive infection of human macrophages.the human immunodeficiency virus (hiv) genetic determinant(s) responsible for tropism in human t cells or macrophages are not well defined. we studied the role of the hiv type 2 (hiv-2) nef and vpr genes in viral tropism. hiv-2 mutants, lacking either vpr or nef genes, or both vpr and nef, were obtained by site-specific mutagenesis of a biologically active hiv-2 proviral clone (hiv-2sbl/isy), which is infectious in both human t cells and macrophages. viral progeny carrying mutations of nef, vpr, ...19902236020
[the human immunodeficiency virus type 2 (hiv-2)]. 19902236770
expression of gag precursor protein and secretion of virus-like gag particles of hiv-2 from recombinant baculovirus-infected insect cells.a recombinant baculovirus carrying the gag gene but lacking the protease coding sequences of human immunodeficiency virus type 2 (hiv-2) has been constructed. when this recombinant baculovirus is used to infect insect cells, a high level of gag precursor protein, gag pr41, is expressed. electron microscopy showed that the majority of gag pr41 was budding through the plasma membrane and being released into the culture medium in spherical virus-like particles with a diameter of approximately 100 n ...19902238477
human immunodeficiency virus type 2 (hiv2).in the mid 1980's a second human retrovirus, capable of causing the acquired immunodeficiency syndrome (aids), was isolated from patients of west african origin. this virus, now called human immunodeficiency virus type 2 (hiv2), was found to be distinct from human immunodeficiency virus type 1 (hiv1) but closely related to simian immunodeficiency viruses (siv). although the genomes of hiv1 and hiv2 are similar there are significant differences in nucleotide and amino acid sequences, most marked ...19902245251
rapid and specific diagnosis of hiv-1 and hiv-2 infections: an evaluation of testing strategies.to identify cost-effective testing strategies for hiv-1 and hiv-2 infections, we evaluated different combinations of tests on serum specimens from 1134 consecutive patients attending tuberculosis treatment centers in abidjan, côte d'lvoire. virus-specific whole-virus enzyme-linked immunosorbent assay (wve), western blot (wb) and synthetic peptide enzyme-linked immunosorbent assay (spe) were used in sequential fashion to determine the true prevalence of infection; 27% were reactive to hiv-1, 5% t ...19902252560
[intestinal spirochetosis in homosexuals infected with hiv. 3 cases].we report 3 cases of intestinal spirochetosis in homosexuals infected with the human immunodeficiency virus (2 group iii and 1 group iv c1, according to the centers for disease control classification) presenting with moderate, chronic diarrhea. the diagnosis was made based on the histological examination of colorectal biopsies showing a layer of spirochetes carpeting the epithelium. electron microscopy evaluation and culturing of the microorganism provided information on the bacterium's morpholo ...19902256590
[intestinal spirochetosis in homosexuals infected with hiv. 3 cases].we report 3 cases of intestinal spirochetosis in homosexuals infected with the human immunodeficiency virus (2 group iii and 1 group iv c1, according to the centers for disease control classification) presenting with moderate, chronic diarrhea. the diagnosis was made based on the histological examination of colorectal biopsies showing a layer of spirochetes carpeting the epithelium. electron microscopy evaluation and culturing of the microorganism provided information on the bacterium's morpholo ...19902256590
in vitro characterization of a biologically active molecular clone of hiv-2nih-z containing a nef deletion and expressing a full-length transmembrane protein.we have previously described the cloning and sequencing of a novel stain of human immunodeficiency virus type 2 (hiv-2) called hiv-2nih-z. a plasmid clone, phiv2z, containing the full-length provirus has now been constructed, and virus particles have been obtained upon transfection into cos-1 and h-9 cells. these particles can infect a number of t-cell lines and exert a cytopathic effect on fresh human and macaque peripheral blood lymphocytes. the cloned virus is biologically and morphologically ...19902265026
[prevalence of hiv-1 and hiv-2 antibodies in rural areas of benin].a transversal survey has been performed in the zou province in the central part of benin located in west africa close to the western border of nigeria. the zou province is an agricultural region which population is about 900,000. a randomised sample of 1936 people had been chosen according 1,984 census data. all the samples have been examined by elisa rapid elavia mixt (pasteur vaccin). all positive samples have been tested with both elavia i and elavia ii (pasteur vaccin). 6.6% of sampled popul ...19902285997
anti-human immunodeficiency virus effects of dextran sulfate are strain dependent and synergistic or antagonistic when dextran sulfate is given in combination with dideoxynucleosides.the effects of three molecular weight ranges of dextran sulfate on five different human immunodeficiency virus (hiv) isolates (from patients with acquired immunodeficiency syndrome), alone and in combination with dideoxynucleosides, were investigated in vitro. the higher the molecular weight range of dextran sulfate, the more potent the activity as assessed by a quantitative syncytium formation assay. although all five hiv isolates had similar susceptibilities to the inhibitory effects of dideox ...19902291665
mutational analysis of the human immunodeficiency virus type 2 (hiv-2) genome in relation to hiv-1 and simian immunodeficiency virus siv (agm).we constructed an infectious molecular clone of the human immunodeficiency virus type 2 (hiv-2) and generated nine frameshift mutants corresponding to nine open reading frames identified so far. three structural (gag, pol, env) and two regulative (tat, rev) gene mutants were not infectious, whereas vif, vpx, vpr, and nef genes were dispensable for infectivity. all of the mutants except env and rev were cytopathic in cd4+ human leukemia cells. in transfection assays, the expression of hiv-2 long ...19902296082
molecular characterization of an attenuated human immunodeficiency virus type 2 isolate.naturally occurring strains of human immunodeficiency virus (hiv) can vary considerably in their in vitro biological properties, and such differences may also be reflected in their in vivo pathogenesis. in an attempt to define genetic determinants of viral pathogenicity, we have molecularly cloned, sequenced, and characterized an attenuated isolate of hiv type 2 (hiv-2/st) that differs from prototype hiv-2 strains in its inability to fuse with and kill susceptible cd4-bearing target cells. a pro ...19902296086
transmembrane envelope glycoproteins of human immunodeficiency virus type 2 and simian immunodeficiency virus siv-mac exist as homodimers.an 80-kilodalton glycoprotein (gp80) was produced in human immunodeficiency virus type 2 (hiv-2)-infected cells along with three envelope glycoproteins that we have recently reported: the extracellular glycoprotein (gp125), the envelope glycoprotein precursor (gp140), and the transient dimeric form of the precursor (gp300). gp125 and gp80 were detectable after the synthesis of gp140 and the formation of gp300. using a specific monoclonal antibody, we showed here that gp80 is a dimeric form of th ...19902296088
isolation and partial characterization of an unusual human immunodeficiency retrovirus from two persons of west-central african origin.an unusual human retrovirus was isolated from two patients with persistent generalized lymphadenopathy who originate from west-central africa and are currently residing in belgium. although the virus shared a number of the same biological and morphological properties as human immunodeficiency retrovirus type 1 (hiv-1) and hiv-2, significant antigenic differences could be demonstrated. several of the viral proteins also differed in molecular weight from the corresponding hiv-1 and hiv-2 proteins. ...19902304140
heat-labile, complement-like factor(s) of animal sera prevent(s) hiv-1 infectivity in vitro.we studied inactivation of hiv-1 by fresh sera of animals. we found that while fresh sera of humans and chimpanzees (among others) did not have antiviral activity, fresh sera of several other mammals, especially those of rodents and felines, showed a dose-dependent viral-inactivating property against cell-free hiv-1; these sera were also capable of inactivating virus preadsorbed to cells, similar to neutralizing antibody. the activity was destroyed by heating to 56 degrees c, required ca2+ but n ...19902313562
a highly conserved rna folding region coincident with the rev response element of primate immunodeficiency viruses.a series of unusual folding regions (ufr) immediately 3' to the cleavage site of the outer membrane protein (omp) and transmembrane protein (tmp) were detected in the envelope gene rna of the human immunodeficiency virus (hiv-1, hiv-2) and simian immunodeficiency virus (siv) by an extensive monte carlo simulation. these rna secondary structures were predicted to be both highly stable and statistically significant. in the calculation, twenty-five different sequence isolates of hiv-1, three isolat ...19902326200
novel sulfated polymers as highly potent and selective inhibitors of human immunodeficiency virus replication and giant cell formation.novel synthetic sulfated polymers, namely, sulfated polyvinyl alcohol (pvas) and sulfated copolymers of acrylic acid with vinyl alcohol (pavas), proved to be potent and selective inhibitors of human immunodeficiency virus type 1 (hiv-1) and hiv-2 in vitro. the compounds completely inhibited hiv-1-induced cytopathogenicity in mt-4 cells and hiv-1 antigen expression in cem cells at a concentration of 0.8 micrograms/ml. they were equally effective against hiv-2 replication. in addition, and in cont ...19902327749
cyclobut-a and cyclobut-g, carbocyclic oxetanocin analogs that inhibit the replication of human immunodeficiency virus in t cells and monocytes and macrophages in vitro.two newly synthesized carbocyclic oxetanocin analogs, (+/-)-9-[(1 beta,2 alpha,3 beta)-2,3-bis(hydroxymethyl)-1-cyclobutyl]adenine (cyclobut-a) and (+/-)-9-[(1 beta,2 alpha,3 beta)-2,3-bis(hydroxymethyl)-1-cyclobutyl]guanine (cyclobut-g) were tested for activity against the infectivity of human immunodeficiency virus (hiv) in vitro. a number of other carbocyclic oxetanocin analogs failed to exert good antiretroviral effects. both cyclobut-a and cyclobut-g protected cd4+ ath8 cells against the in ...19902327778
human immunodeficiency virus does not induce interleukin-1, interleukin-6, or tumor necrosis factor in mononuclear cells.the production of interleukin-1 beta (il-1 beta), il-6, and tumor necrosis factor alpha (tnf-alpha) by fresh peripheral blood mononuclear cells was evaluated after exposure to human immunodeficiency virus (hiv) or purified recombinant hiv-1 envelope glycoprotein (rgp120). to exclude the role of contaminating endotoxin in this study, all media were subjected to ultrafiltration and reagents contained less than 25 pg of endotoxin per ml by limulus assay. under endotoxin-free conditions, no increase ...19902335821
isolation and characterization of simian immunodeficiency viruses from two subspecies of african green monkeys.cercopithecus aethiops (african green monkey), a nonhuman primate species distributed throughout subsaharan africa, has been shown to have high seroprevalence rates of antibodies to simian immunodeficiency virus (siv), and therefore, has been proposed as a natural reservoir for immunodeficiency viruses. our laboratories have isolated siv-like viruses from two east african subspecies of c. aethiops designated grivet and vervet monkeys. analysis of the structural proteins based on the molecular we ...19902340199
human immunodeficiency virus types 1 and 2 and simian immunodeficiency virus env proteins possess a functionally conserved assembly domain.the envelope (env) glycoproteins of human immunodeficiency viruses type 1 (hiv-1) and type 2 (hiv-2) form dimers shortly after synthesis. analysis of the simian immunodeficiency virus (siv) env protein expressed by a recombinant vaccinia virus revealed that it, too, forms stable homodimers. when the hiv-1 and siv env proteins or the hiv-1 and hiv-2 env proteins were coexpressed in the same cells, heterodimers were formed. thus, the env proteins of hiv-1, hiv-2, and siv possess a functionally con ...19902352332
a novel proviral clone of hiv-2: biological and phylogenetic relationship to other primate immunodeficiency viruses.infectious molecular clones of the human immunodeficiency virus type 2 (hiv-2) will be valuable tools for the study of regulatory gene functions and the development of an animal model for the human acquired immunodeficiency syndrome (aids). to this end, we have cloned and sequenced a novel hiv-2 isolate, hiv-2ben. one clone, designated mk6, is infectious for various human t-cell lines and for human and macaque peripheral blood lymphocytes (pbl), allowing molecular studies of hiv-2 infection and ...19902353457
[statement: the evaluation of the serodia-hiv and serodia-atla fujirebio-miles kits].a new test, based on agglutination of gelatin particles (pa), sensitized with viral antigens of hiv, was applied on detection of the human immunodeficiency virus (hiv 1) antibody. sensitivity compared to the elisa tests (organon, dupond de nemours and/or elavia 2) was the same during the screening test (97.7 p. cent). specificity was also acceptable when compared to the same tests (94 p. cent). this specificity remains acceptable with african sera (96 p. cent). during screening, 11.8 p. cent of ...19902353752
[leukocytoclasic vasculitis and human immunodeficiency virus. 2 new cases]. 19902359963
detection of serum antibodies to retroviral proteins in patients with primary sjögren's syndrome (autoimmune exocrinopathy).primary sjögren's syndrome (ss) is considered a benign autoimmune disease; it is characterized by lymphoid infiltration of salivary and lacrimal glands, often accompanied by the presence of serum autoantibodies, particularly anti-ro (ss-a) and anti-la (ss-b). there are important immunologic similarities between primary ss and acquired immunodeficiency syndrome. to investigate for a possible immune response to retroviral proteins in primary ss, we performed immunoblotting against human immunodefi ...19902363733
the env protein of an infectious noncytopathic hiv-2 is deficient in syncytium formation.a recent isolate of human immunodeficiency virus type 2 (hiv-2) designated hiv-2st is deficient in its ability to cause the typical cytopathic effects of hiv infection. the pathogenic potential of hiv-2 in inducing human disease may be less than that of hiv-1, and it is of particular interest to establish the basis for the reduced cytopathogenicity of this isolate in vitro. utilizing recombinant vaccinia viruses (rvv) carrying the envelope genes (env) of hiv-2st or those of fully cytopathic hiv- ...19902364016
aids risk and prevention in transfusions.transfusion of blood and blood products range from 2 to 8% of the cases of aids. the identification of hiv viral agent and the appearance of tests designed to detect antibodies associated with mechanisms of autologous transfusions and inactivation of virus of clotting factors concentrates have contributed to decrease this mean of transmission. some aspects such as the difference of sensitivity in the tests, immunologic windows, and the appearance of new viruses such as the hiv 2 increase the com ...19902370875
[prevalence of type 1 human immunodeficiency virus (hiv) infection in african patients residing in catalonia].278 black patients from west africa, living in maresme, a coastal area north of barcelona were studied in order to determine the prevalence of hiv-1 infection. during the first period (1984-86), 102 patients were studied, 3 of them were positive for hiv-2, but none was positive for hiv-1. in the second period (1987-89), 176 patients were studied and 15 were positive for hiv-1. sexual intercourse with prostitutes of low social level was the only risk factor in all of them. nine of these 15 patien ...19902377013
simple, sensitive, and specific detection of human immunodeficiency virus type 1 in clinical specimens by polymerase chain reaction with nested primers.a simple, sensitive, and specific polymerase chain reaction (pcr) protocol for the detection of human immunodeficiency virus type 1 (hiv-1) is described. we have improved all three pcr steps: sample preparation, dna amplification, and detection of the amplified product. some of the improvements have been described previously, but they have never been combined into a complete pcr protocol. peripheral blood mononuclear cells were lysed directly in a buffer containing sodium dodecyl sulfate, triton ...19902380380
infection of nonlymphoid cells by human immunodeficiency virus type 1 or type 2.human epithelial cells (l132) derived from embryonic lung and human lung fibroblasts (mrc5) were infected by human immunodeficiency virus type 1 (hiv-1) or type 2 (hiv-2). surface cd4 protein was detected on these cells, and recombinant soluble cd4 (scd4) blocked infection, indicating that hiv infection was mediated by the cell surface cd4 protein. in contrast, infection of human primary chondrocyte cells (c23), synovial cells (hsa), and foreskin fibroblasts (f13) was apparently independent of c ...19902384919
experimental infection of macaques with hiv-2ben, a novel hiv-2 isolate.ten rhesus (macaca mulatta) and six fascicularis (macaca fascicularis) macaques were inoculated with hiv-2ben using three different virus preparations and two routes of inoculation. thirteen of the 16 inoculated macaques seroconverted 2-6 weeks after infection. three m. mulatta remained seronegative. the seroconverted animals developed antibody titres from 80 to 40,000. their antibodies reacted with gp160 and gp130 and, in varying degrees, with gp32 and core proteins. virus could be re-isolated ...19902397054
cd4 immunoadhesin, but not recombinant soluble cd4, blocks syncytium formation by human immunodeficiency virus type 2-infected lymphoid cells.recombinant soluble cd4 (rcd4) has been shown to be an effective inhibitor of human immunodeficiency virus type 1 (hiv-1) and hiv-2 infection of lymphoid cells in vitro. in this report, we characterized the effects of rcd4, the v1v2 fragment of cd4, and the immunoadhesin cd4-immunoglobulin g on syncytium formation between lymphoid cells infected by hiv-1 or hiv-2 and uninfected cells. all three molecules blocked hiv-1-mediated syncytium formation, but only cd4-immunoglobulin g blocked hiv-2-medi ...19902398542
absence of hiv infection in blood donors with indeterminate western blot tests for antibody to hiv-1.to determine whether apparently healthy persons who have had repeatedly reactive enzyme immunoassays and an indeterminate western blot assay for antibody to the human immunodeficiency virus type 1 (hiv-1) are infected with hiv-1 or hiv-2, we studied 99 such volunteer blood donors in a low-risk area of the country. the subjects were interviewed about hiv risk factors. coded blood specimens were tested again for hiv-1 antibody (by two different enzyme immunoassays, a western blot assay and a radio ...19902403658
novel sulfated polysaccharides: dissociation of anti-human immunodeficiency virus activity from antithrombin activity.novel sulfated polysaccharides, sulfated bacterial glycosaminoglycan (org 31581) and chemically degraded heparin (org 31733), have proved to be potent and selective inhibitors of human immunodeficiency virus (hiv) in vitro. their 50% inhibitory concentrations for hiv type 1 (hiv-1) in mt-4 cells were 0.67 and 0.52 micrograms/ml, respectively. these values are comparable to those obtained for dextran sulfate and standard heparin (0.39 and 0.89 micrograms/ml, respectively). org 31581 and org 31733 ...19902405068
hiv-2 link to aids in west africa.to date, very little is known concerning the clinical spectrum of human immunodeficiency virus type 2 (hiv-2) infection, and the question as to whether hiv-2 will ultimately prove to be as pathogenic as human immunodeficiency virus type i (hiv-1) remains, as yet, unanswered. we reviewed the currently available reports of hiv-2 infection to assess what is known about the extent of hiv-2 pathogenicity as it compares to hiv-1 pathogenicity. there is evidence that hiv-2 is associated with aids. most ...19902406413
synthetic peptide assays to detect human immunodeficiency virus types 1 and 2 in seropositive individuals.detection of antibodies to human immunodeficiency virus type 1 by enzyme-linked immunosorbent assay is the standard method to screen blood products. with the description of human immunodeficiency virus type 2 as a second retrovirus involved in the pathogenesis of acquired immunodeficiency syndrome, additional laboratory testing is required to screen blood products. however, owing to the serological cross-reactivity of human immunodeficiency virus types 1 and 2 at the molecular level, it is impos ...19902407213
[aids in senegal].in senegal, aids was 1st discovered in december 1986 going from 6 cases in 1987, to 181 in 1988, to 269 in 1989, and to 361 in june of 1990. senegal has the hiv-2 virus, which has a longer incubation period than the hiv-1 virus and its incidence is becoming a growing problem. unlike most other countries in africa, senegal did not institute an aids program with the world health organization; but signed a contract with harvard, tours and lomoges universities to undertake research on aids, sexual ...199012342926
[strategies and prevention of the increase of aids in africa].there is great concern over the prevalence of the acquired immunodeficiency syndrome (aids) in sub-saharan africa (ssa), especially because of the existence of the hiv-1 and hiv-2 viruses. for example, in senegal 9.8% of all prostitutes are infected with the hiv-2 virus as against 1.3% infected with the hiv-1 virus, and 0.7% infected by the 2 viruses. this situation has created many logistical problems for ssa as quoted from dr. ngaly's presentation at the international aids conference in mont ...199012342927
aids: understanding cause and effect.this article discusses the history, pathology, and symptoms of aids. caused by human immunodeficiency virus (hiv), aids was first detected in 1981 among the american homosexual population, later spreading to other populations, including hemophiliacs and intravenous drug users. this led epidemiologists to deduce that aids spreads through body fluids. in 1983, french scientists isolated the virus which late came to be known as hiv-1. and in 1987, scientists identified another virus capable of ...199112284230
inhibition of human immunodeficiency virus type 1 (hiv-1) replication by the dipyridodiazepinone bi-rg-587.the dipyridodiazepinone human immunodeficiency virus type 1 (hiv-1)-specific reverse transcriptase (rt) inhibitor bi-rg-587 was tested for its ability to inhibit hiv-1 replication in both acutely and chronically infected cell lines. the ability of bi-rg-587 to inhibit steps in the virus replicative cycle other than reverse transcription was also assessed. bi-rg-587 was found to be a potent inhibitor of hiv-1 replication in acutely infected cells (50% inhibitory concentration [ic50] = 37.2 nm), a ...19911708400
dehydroandrographolide succinic acid monoester as an inhibitor against the human immunodeficiency virus.dehydroandrographolide succinic acid monoester (dasm) is the dehydroandrographolyl ester of succinic acid; and andrographolide, from which dasm is made, is the major diterpenoid lactone found in the chinese medicinal herb, andrographis paniculata. dasm has been found to be an inhibitor against the human immunodeficiency virus (hiv) in vitro. it was nontoxic to the h9 cell at the concentrations of 50-200 (average, 108) micrograms/ml and was inhibitory to the hiv-1 (iiib) at the minimal concentrat ...19911708503
bi-rg-587 is active against zidovudine-resistant human immunodeficiency virus type 1 and synergistic with zidovudine.a series of dipyridodiazepinones have been shown to be potent inhibitors of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase. the lead compound, bi-rg-587, had a 50% inhibitory concentration of 84 nm against hiv-1 reverse transcriptase activity. this compound reduced plaque formation of hiv-1 in hela cells expressing the cd4 receptor by 50% at 15 nm. bi-rg-587 at comparable concentrations inhibited the production of p24 antigen following the acute infection of cem t-lymphoblasto ...19911708976
selective antiviral activity of synthetic soluble l-tyrosine and l-dopa melanins against human immunodeficiency virus in vitro.melanins are pigments found in hair, skin, irides of the eye, and brain. their functions in mammals include protection from exposure to sunlight, camouflage from predators, sexual recognition within species, and possible electron transfer reactants. most natural melanins exist in an insoluble form, which is one reason there is little information on the biological properties of soluble melanins. here, synthetic soluble melanins were obtained by chemical oxidation of l-tyrosine or spontaneous oxid ...19911709802
immune response to a major epitope of p24 during infection with human immunodeficiency virus type 1 and implications for diagnosis and prognosis.a sequential inhibition enzyme-linked immunoassay (sieia) using a peroxidase-conjugated monoclonal antibody reacting to the sequence aaewdrvhp of p24hiv-1 (amino acids 209 to 217 of p55) was developed in order to detect and determine the titer of antibody to this epitope in various populations of human immunodeficiency virus type 1 (hiv-1)-positive patients. there was a good correlation between sieia and a commercially available competition assay that uses recombinant p24 protein and polyclonal ...19911709947
in vitro efficacy of anti-hiv immunotoxins targeted by various antibodies to the envelope protein.six different anti-hiv envelope antibodies and one irrelevant control antibody were coupled to ricin a chain and tested for their efficacy in inhibiting hiv tissue culture infections. the anti-hiv antibodies consisted of five monoclonals, three of murine and two of human origin, and one polyclonal preparation prepared by affinity purifying pooled serum antibodies from hiv-infected humans on rgp160. the binding specificity of the antibodies was defined by elisa by using recombinant envelope prote ...19911710247
characterization of human antibody-binding sites on the external envelope of human immunodeficiency virus type 2.antibody-reactive peptide scanning (pepscan) using overlapping nonapeptides and human sera as probes allows the identification of amino acids contributing significantly to antigen-antibody interaction. five-hundred and two overlapping nonapeptides derived from the human immunodeficiency virus type 2 strain rod (hiv-2rod) external envelope glycoprotein gp125 were synthesized to serve as probes for reactivity with eight sera of hiv-2-infected individuals. fifteen antibody-binding regions were iden ...19911710645
highly potent and selective inhibition of human immunodeficiency virus type 1 by a novel series of 6-substituted acyclouridine derivatives.in the search for novel derivatives of 1-[2-(hydroxyethoxy)methyl]-6-(phenylthio)thymine (hept), we have found that several 5-ethyl-6-(3,5-dimethylphenylthio)uracil and 5-ethyl-6-(3,5-dimethylbenzyl)uracil analogues are exquisitely potent and selective inhibitors of human immunodeficiency virus type 1 (hiv-1) replication in a variety of cell culture systems. of this series, 5-ethyl-1-ethoxymethyl-6-(3,5-dimethylbenzyl)uracil (e-ebu-dm) emerged as the most active congener. its 50% inhibitory conc ...19911711148
9-[(2rs)-3-fluoro-2-phosphonylmethoxypropyl] derivatives of purines: a class of highly selective antiretroviral agents in vitro and in vivo.a new class of compounds, 9-[(2rs)-3-fluoro-2-phosphonylmethoxypropyl] [(rs)-fpmp] derivatives of purines, is described that has selective activity against a broad spectrum of retroviruses [including human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2)] but not other rna or dna viruses. this activity spectrum is completely different from that of the parental compounds, 9-[(2s)-3-hydroxy-2-phosphonylmethoxypropyl] [(s)-hpmp] derivatives of purines, which are active against a broad range ...19911711214
comparison of linear antigenic sites in the envelope proteins of human immunodeficiency virus (hiv) type 2 and type 1.the occurrence of dominant linear antigenic sites in the envelope glycoproteins of human immunodeficiency virus type 2 (hiv-2) was evaluated. twenty-five peptides representing different regions of hiv-2, strain sbl-6669, were synthesized. for comparison the corresponding peptides of hiv-1, strain bru, were also prepared. the peptides were tested in enzyme-linked immunosorbent assay (elisa) with human sera from individuals with proven hiv-1 or hiv-2 infection and simian sera from animals infected ...19911712215
monoclonal antibodies define linear and conformational epitopes of hiv-1 pol gene products.purified recombinant reverse transcriptase (rt) from human immunodeficiency virus type 1 (hiv-1) was used to raise 21 monoclonal antibodies with anti-rt specificities. the antibodies were characterized using western blotting against native virus and recognized either the p66 or p66, p51 components of rt. further immunoblotting using either cyanogen bromide fragmented rt or truncated mutants of rt along with cross-competition studies enabled the location of various immunogenic regions of rt to be ...19911712217
competition elisa using a human monoclonal antibody for detection of antibodies against human immunodeficiency virus type 1.a novel competition elisa for detection of antibodies against hiv-1 was developed. the assay is based on competition at the single epitope level and utilises a human monoclonal antibody and an e. coli-produced fragment of the transmembrane glycoprotein gp41. the sensitivity of the assay was 100% in tests on 247 serum samples obtained from 219 individuals previously shown to be hiv-1 antibody positive by both conventional indirect elisa and the immunoblotting test. the patients represented variou ...19911712361
characterization of murine monoclonal antibodies directed against the core proteins of human immunodeficiency virus types 1 and 2.monoclonal antibodies (mabs) raised against the core proteins of human immunodeficiency virus type 1 (hiv-1; laboratory strain htlv-iiib) and hiv-2 (strain rod) were investigated in a variety of tests, e.g., enzyme-linked immunosorbent assay (elisa), immunostaining of western immunoblots, immunofluorescence, immunoprecipitation, and alkaline phosphatase anti-alkaline phosphatase assay. the mabs were grouped according to their cross-reactions. seven hiv-1-specific mabs reacted exclusively with hi ...19911712863
expression of the heterodimeric form of human immunodeficiency virus type 2 reverse transcriptase in escherichia coli and characterization of the enzyme.a system for the expression of recombinant human immunodeficiency virus type 2 (hiv-2) reverse transcriptase (rt) in escherichia coli has been developed, which allows purification of the heterodimeric form of the enzyme as well as the separate purification of the two subunits. it is shown that equilibrium formation between monomeric and homodimeric forms of the recombinant 66- and 51-kda subunits is considerably more rapid than in the case of the corresponding homodimeric forms of hiv-1 rt. in a ...19911713589
oxathiin carboxanilide, a potent inhibitor of human immunodeficiency virus reproduction.oxathiin carboxanilide (oc), nsc 615985, a compound originally synthesized as a potential fungicide, was demonstrated to be highly active in preventing human immunodeficiency virus (hiv)-induced cell killing and in inhibiting hiv reproduction. virus-infected cd4+ lymphocytes were completely protected by 0.5 microm oc, whereas no toxicity was observed at concentrations below 50 microm oc. production of infectious virus, viral p24 antigen, and virion reverse transcriptase were reduced by oc at con ...19911713689
characterization of monoclonal antibodies against the human immunodeficiency virus matrix protein, p17gag: identification of epitopes exposed at the surfaces of infected cells.eight monoclonal antibodies reactive with the matrix protein of human immunodeficiency virus type 1 (hiv-1), p17gag, were isolated from rats which had been immunized with solubilized hiv-1 lysate. the epitope specificities of these antibodies were determined with a series of synthetic peptides representing overlapping regions of p17. six of the antibodies were mapped to three distinct regions of p17, while two antibodies (g11g1 and g11h3) reacted only with intact recombinant p17, suggesting that ...19911714518
several cd4 domains can play a role in human immunodeficiency virus infection in cells.the human immunodefiency virus (hiv) uses the human cd4 glycoprotein as a receptor for infection of susceptible cells. cells expressing a series of mutated forms of the cd4 gene have shown a variability in their ability to support replication of three hiv type 1 (hiv-1) and three hiv-2 strains. moreover, when different stages of virus production were examined by a variety of assays, a consistent delay was observed in all cell lines containing cd4 mutants compared with those with intact full-leng ...19911714523
localization of immunogenic domains in the human immunodeficiency virus type 2 envelope.highly immunogenic domains have not yet been defined in the extracellular protein of the human immunodefiency virus type 2 (hiv-2) envelope. in this study, six contiguous segments covering the entire hiv-2st envelope were amplified and cloned into a bacterial expression vector to localize the relative immunogenic reactivity of different regions of the molecule by western blot (immunoblot) analysis. our results demonstrate that the extracellular protein of the hiv-2 envelope contains highly immun ...19911714524
the vpx gene of simian immunodeficiency virus facilitates efficient viral replication in fresh lymphocytes and macrophage.vpx is a unique open reading frame found in simian immunodeficiency virus (siv) and human immunodeficiency virus type 2 (hiv-2) but not in hiv-1. it encodes a 12- to 16-kda virion-associated protein. although vpx is dispensable for viral replication in several established human lymphocyte cell lines, there is no consensus regarding whether this gene is required for efficient viral replication in freshly isolated lymphocytes. we report here that the vpx mutant of sivmac exhibits different degrees ...19911714525
human immunodeficiency virus type 2 vpx protein augments viral infectivity.the genomes of hiv and siv are complex and contain several accessory genes which modulate viral replication and pathogenicity. one of these genes, vpx, is unique to the hiv-2/siv group of viruses and encodes a virion-associated protein of unknown function. to examine the function of vpx, we constructed a vpx-deficient hiv-2 proviral clone and characterized its in vitro biological properties. following transfection into immortalized t-cell lines, vpx-mutant hiv-2 was fully replication competent a ...19911714662
characterization of monoclonal antibodies identifying type and strain-specific epitopes of human immunodeficiency virus type 1.several hybridoma cell lines were raised against the highly cytopathic zaïrian isolate of human immunodeficiency virus (hiv), hiv1-ndk. the specificity of the secreted monoclonal antibodies (mab) was demonstrated by immunoblotting, radioimmunoprecipitation and immunofluorescence. two hybridoma cell lines secreted mab reacting with independent epitopes of the ndk p17 capsid protein and its precursors. one, rl16.24.5, is specific for the ndk isolate whereas the other, rl16.45.1, along with anti-p2 ...19911715507
compatibility of rev gene activity in the four groups of primate lentiviruses.the compatibility of rev genes derived from various primate immunodeficiency viruses of all distinct subgroups identified was assessed in three experimental systems: complementation experiments between proviral rev and gag mutants, evaluation of the ability of the rev gene products to activate proviral reporters, and examination of the capacity of various viruses to augment marker gene expression in the infected reporter cell lines. in all systems, human immunodeficiency virus type 1 (hiv-1) rev ...19911716025
nonnucleoside reverse transcriptase inhibitors that potently and specifically block human immunodeficiency virus type 1 replication.certain bis(heteroaryl)piperazines (bhaps) are potent inhibitors of the human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt) at concentrations lower by 2-4 orders of magnitude than that which inhibits normal cellular dna polymerase activity. combination of a bhap with nucleoside analog hiv-1 rt inhibitors suggested that together these compounds inhibited rt synergistically. in three human lymphocytic cell systems using several laboratory and clinical hiv-1 isolates, the bhaps b ...19911717988
human immunodeficiency virus can infect the apical and basolateral surfaces of human colonic epithelial cells.the gastrointestinal tract is considered to be a major route of infection for the human immunodeficiency virus (hiv). to understand the interaction of hiv with epithelial cells of the intestinal mucosa, we have studied the infection of a human colon cancer cell clone ht-29-d4. the enterocyte-like differentiation of this clone can be modulated in vitro according to the concentration of glucose. we show that: (i) undifferentiated ht-29-d4 cells can be infected by hiv types 1 and 2 (hiv-1 and hiv-2 ...19911718004
effect of evans blue and trypan blue on syncytia formation and infectivity of human immunodeficiency virus type i and type ii in vitro.polyanionic compounds were used to inhibit infectivity of human immunodeficiency virus in vitro. suramin, evans blue, and trypan blue were shown to inhibit syncytia formation normally observed when hiv-1-infected cells are cocultured with cd4+ cells. the inhibition was more pronounced with evans blue than with any of the other polyanions studied. the inhibitory effect was significantly weaker in hiv-2 systems. however, the reverse transcriptase activities of both types of viruses were inhibited ...19911718343
broadly neutralizing antibodies targeted to mucin-type carbohydrate epitopes of human immunodeficiency virus.the cancer-related mucin-type carbohydrate neoantigen tn was found on gp160 and gp120 of human immunodeficiency virus (hiv). immunoglobulin g (igg) and igm monoclonal antibodies (mabs) against tn neutralized infection with cell-free virus and blocked fusion between hiv-infected and uninfected cells. this inhibition was found in infection of both lymphocytic cells and monocytoid cells. viruses tested included six hiv-1 and five hiv-2 isolates propagated in different cells, as well as infectious p ...19911719230
chimeric human immunodeficiency virus type 1/type 2 reverse transcriptases display reversed sensitivity to nonnucleoside analog inhibitors.human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt), an important therapeutic target in the treatment of aids, is effectively inhibited by a class of nonnucleoside analog compounds that includes nevirapine (bi-rg-587) and tetrahydroimidazo[4,5,1-jk]-[1,4]benzodiazepin-2(1h)-one and -thione. we show that both tyrosine residues at positions 181 and 188 flanking the putative catalytic site of hiv-1 rt are required for sensitivity of the enzyme to these compounds. hiv-2 rt, which ...19911719542
antibody to reverse transcriptase of human retroviruses in multiple sclerosis.htlv-1, hiv-1 and hiv-2 western blot analysis of sera from patients with multiple sclerosis (ms), from patients with other neurological diseases and from blood donors, revealed a rather frequent cross-reactivity with retroviral proteins in the ms group, though no patient was positive with the corresponding specific elisa serology. statistical analysis revealed a significant difference between the ms group and the two control groups for hiv-1 and hiv-2 reverse transcriptase fragments and for htlv ...19911724334
general principles of retrovirus immunodetection tests.because infecting retroviruses contain protein and glycoprotein antigenic determinants that can be readily distinguished from host cell determinants, the development of immunologic detection systems, immunodetection tests, or immunoassays capable of identifying antigens of some retroviruses (oncoretroviruses) in blood, body fluids, or cells is possible. conversely, detection of antibodies produced by animals against some infecting retroviruses can also be used to identify current infections of l ...19911724772
a tibo derivative, r82913, is a potent inhibitor of hiv-1 reverse transcriptase with heteropolymer templates.r82913, (+)-s-4,5,6,7-tetrahydro-9-chloro-5-methyl-6-(3-methyl-2-butenyl)- imidazo[4,5,1-jk][1,4]-benzodiazepin-2(1h)-thione (a tibo derivative), inhibited the replication of thirteen different strains of hiv-1 in cem cells with a median ic50 of 0.15 microm. the concentration of compound that killed 50% of the cells was much higher (46 microm), indicating that r82913 has a high selectivity index. r82913 was 20-fold more potent than azt-tp in the inhibition of hiv-1 reverse transcriptase in an as ...19911725247
[current aspects of hiv infection].the epidemiology of hiv-1 and hiv-2 infection in 1989/90 shows a further spread of both viruses, especially in southern europe, eastern asia and central africa. the sequence analysis of an immunodeficiency virus of a chimpanzee indicates the presence of siv-1, in contrast to all other monkey isolates analyzed hitherto as members of siv-2. the occurrence of eight newly hiv-infected hemophiliacs by one factor ix product gives rise to the question whether a 100% safety of blood products can be achi ...19911725606
differential inhibitory effects of sulfated polysaccharides and polymers on the replication of various myxoviruses and retroviruses, depending on the composition of the target amino acid sequences of the viral envelope glycoproteins.sulfated polysaccharides (i.e., dextran sulfate) and sulfated polymers (i.e., sulfated polyvinylalcohol and sulfated copolymers of acrylic acid with vinylalcohol) were found to be potent and selective inhibitors of the replication of respiratory syncytial virus (rsv) and influenza virus type a (influenza a virus) but not of other myxoviruses (parainfluenza 3, measles, and influenza b viruses). the compounds were also inhibitory to human immunodeficiency virus type 1 (hiv-1) and hiv-2 and simian ...19911725692
production and characterization of mouse monoclonal antibodies against the transmembrane protein of a human immunodeficiency virus type 2.we established seven hybridoma clones producing monoclonal antibodies (mabs) against the envelope transmembrane protein (tmp) of a ghanian isolate of human immunodeficiency virus type 2 (hiv-2[gh-1]) from mice immunized with the detergent-disrupted purified whole virus. the mabs were found to react with 35 kilodalton (kd) tmp of the hiv-2[gh-1] virus in a western blot assay (wb). two of these mabs recognized 135 kd proteins in addition to tmp in the lysate of hiv-2[gh-1]-infected cells. two othe ...19911725959
human chromosome-dependent and -independent pathways for hiv-2 trans-activation.human immunodeficiency virus (hiv types 1 and 2) replication is controlled by the interaction of viral-encoded regulatory proteins and host cellular proteins with the viral long terminal repeat (ltr). the presence of hiv-1 and hiv-2 trans-activator proteins, tat1 and tat2, respectively, greatly increases viral gene expression from their homologous ltrs. it is unclear if the cellular factors that support tat1-directed trans-activation of the hiv-1 ltr are the same for tat2 trans-activation of the ...19911760228
inhibition of hiv replication in acute and chronic infections in vitro by a tat antagonist.the human immunodeficiency virus-1 (hiv-1) trans-activator tat is an attractive target for the development of antiviral drugs because inhibition of tat would arrest the virus at an early stage. the drug ro 5-3335 [7-chloro-5-(2-pyrryl)-3h-1,4-benzodiazepine-2(h)-one], inhibited gene expression by hiv-1 at the level of transcriptional trans-activation by tat. the compound did not inhibit the basal activity of the promoter. both tat and its target sequence tar were required for the observed inhibi ...19911763331
low prevalence of human immunodeficiency virus-1 (hiv-1), hiv-2, and human t cell lymphotropic virus-1 infection in somalia.a seroepidemiologic survey was conducted to determine the prevalence of human immunodeficiency virus type 1 (hiv-1), hiv-2, human t cell lymphotropic virus type i (htlv-i), and treponema pallidum infection among southern somalis. sera were collected from 1,269 study subjects in the urban area of the capital city, mogadishu, and in the rural towns of merka, qoryoley, and kismayo. the subjects included 57 prostitutes, 79 sexually transmitted disease (std) patients, and 1,133 others, including outp ...19911763791
identification of mixed hiv-1/hiv-2 infections in brazil by polymerase chain reaction.analysis of sera from hospitalized brazilian patients by whole-virus lysate-based enzyme immunoassay and western blot indicated that 0.4% were reactive to hiv-2 alone while 4% were reactive to both hiv-1 and hiv-2. when these sera were tested for hiv antibody by type-specific peptide enzyme immunoassays, dual seropositivity was confirmed in only 0.4% of patients. to define genetically the hiv strains within the population, we analyzed peripheral blood mononuclear cells from selected seropositive ...19911768377
recovery of human immunodeficiency virus from asymptomatic prostitutes from tamil nadu.peripheral blood mononuclear cells (pbmc) from 13 asymptomatic healthy human immunodeficiency virus type-1 (hiv-1) antibody positive prostitutes from tamil nadu, southern india, were cocultivated with phytohemagglutinin stimulated pbmc from hiv antibody negative donors for hiv isolation. in addition, plasma samples from two antibody positive prostitutes with hiv antigenemia were processed for virus isolation. the presence of virus in the cultures was monitored by (i) assay for virus particle ass ...19911778612
no evidence of hiv-2 infection in subjects at risk for aids living in north-east italy.sera samples from 1134 individuals (824 hiv-1 seropositive and 310 hiv-1 seronegative), collected from january 1988 to april 1990, were tested for hiv-2 antibodies by whole virus assays and synthetic peptide-based assays to determine the prevalence of hiv-2 infection in populations at risk for aids in north-east italy (veneto region). partial reactivities on hiv-2 western blot were a common finding in hiv-1 seropositive samples. none of the sera fulfilled the criteria for hiv-2 seropositivity, s ...19911783062
comparative evaluation of 36 commercial assays for detecting antibodies to hiv.summarized are the results of an assessment of the major operational characteristics of 36 commercially available assays for detection of antibodies to human immunodeficiency virus type 1 (hiv-1) and/or type 2 (hiv-2). for this purpose, 20 enzyme-linked immunosorbent assays (elisas), 11 simple immunoassays with visual reading, four supplemental assays, and one discriminatory assay were assessed using a panel of 537 sera (65% of which were of african, 26% of european, and 9% of south american ori ...19911786625
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