| initiation of (-) strand dna synthesis from trna(3lys) on lentiviral rnas: implications of specific hiv-1 rna-trna(3lys) interactions inhibiting primer utilization by retroviral reverse transcriptases. | initiation of minus (-) strand dna synthesis was examined on templates containing r, u5, and primer-binding site regions of the human immunodeficiency virus type 1 (hiv-1), feline immunodeficiency virus (fiv), and equine infectious anemia virus (eiav) genomic rna. dna synthesis was initiated from (i) an oligoribonucleotide complementary to the primer-binding sites, (ii) synthetic trna(3lys), and (iii) natural trna(3lys), by the reverse transcriptases of hiv-1, fiv, eiav, simian immunodeficiency ... | 1996 | 8816751 |
| a field test for the detection of antibodies to human immunodeficiency virus types 1 and 2 in serum or plasma. | in response to the need for simple and rapid tests for infectious diseases, we have devised a test for antibodies to human immunodeficiency virus type 1 (hiv-1) and hiv-2 which resembles many contemporary strip-style pregnancy tests in format and ease of use. the test was evaluated with 2,928 serum specimens (1,541 reactive and 1,387 nonreactive) collected and tested at a mexico city hospital clinic and was compared with a laboratory assay (abbott) performed simultaneously. the sensitivity and s ... | 1996 | 8807218 |
| lessons from the second aids virus, hiv-2. | although the clinical signs and symptoms of human immunodeficiency virus (hiv)-2 are similar to those associated with hiv-1 infection, the former virus has a markedly lower perinatal transmission rate and heterosexual infectivity potential. an ongoing cohort study in senegal, where the disease was first encountered a decade ago, of 136 hiv-2-infected women found an overall incidence of acquired immunodeficiency syndrome of only 0.18/100 person-years in 548 person-years of observation. moreover ... | 1996 | 8805859 |
| retrovirus and filovirus "immunosuppressive motif" and the evolution of virus pathogenicity in hiv-1, hiv-2, and ebola viruses. | the "immunosuppressive motif" was found to be present in the glycoproteins of retroviruses and filoviruses. this sequence is also conserved in the pathogenic lentiviruses, hiv-1 and siv, and is absent from hiv-2 gp41 and from an apathogenic simian retrovirus. the present analysis deals with the possible involvement of the "immunosuppresessive motif" in the pathogenicity of retroviruses and filoviruses, and the reasons for the conservation of this motif. the ancestral gene from which the "immunos ... | 1995 | 8828145 |
| t-helper reactivity to simian immunodeficiency virus gag synthetic peptides in human immunodeficiency virus type 2 infected individuals. | west african populations are infected with divergent strains of human immunodeficiency virus type 2 (hiv2), some of which are closely related to simian immunodeficiency virus (siv) and it has been postulated that the hiv2 epidemic might have arisen by cross-species spread of siv into the human population in west africa. to gain some insight into the possible basis for cross protection between these two closely related viruses, the t-helper responses to 15 synthetic peptides from siv gag syntheti ... | 1995 | 8830117 |
| acyclic nucleotide analogs derived from 8-azapurines: synthesis and antiviral activity. | reaction of phosphoroorganic synthons with 8-azaadenine, 8-aza-2, 6-diaminopurine, and 8-azaguanine using cesium carbonate yielded regioisomeric 8-azapurine n7-, n8-, and n9-(2-(phosphonomethoxy)alkyl) derivatives. this reaction followed by deprotection afforded isomeric 2-(phosphonomethoxy)ethyl (pme), (s)-(3-hydroxy-2-(phosphonomethoxy)propyl) [(s)-hpmp], (s)-(3-flouro-2-(phosphonomethoxy)propyl) [(s)-fpmp], (s)-(2-(phosphonomethoxy)propyl) [(s)-pmp], and (r)-(2-(phosphonomethoxy)propyl) [(r)- ... | 1996 | 8831773 |
| detection of circulating human immunodeficiency virus type 2 in plasma by reverse transcription polymerase chain reaction. | genomic rna was detected using a reverse transcription (rt) nested polymerase chain reaction (pcr) method on plasma from 24 hiv2-infected patients. results were interpreted based on immune and clinical status and results of plasma and cellular viraemia assays. amplification of rna extracted from plasma was positive in 13 of the 24 cases studied (54%). there was a negative correlation between the detection of rna in plasma and the patients' cd4+ cell counts: all 5 patients with counts below 200 x ... | 1995 | 8834757 |
| antiviral and resistance studies of ag1343, an orally bioavailable inhibitor of human immunodeficiency virus protease. | ag1343 ([3s-(3r*,4ar*,8ar*,2's*,3's*)]-2-[2' hydroxy-3'-phenylthiomethyl-4'-aza-5'-oxo-5'-(2''-methyl-3''-hydro xy-phenyl) pentyl]-decahydroiso-quinoline-3-n-t-butylcarboxamide methanesulfonic acid) is a selective, nonpeptidic inhibitor of human immunodeficiency virus (hiv) protease (ki = 2 nm) that was discovered by protein structure-based drug design methodologies. ag1343 was effective against the replication of several laboratory and clinical hiv type 1 (hiv-1) or hiv-2 isolates including pyr ... | 1996 | 8834868 |
| a model for alignment of env v1 and v2 hypervariable domains from human and simian immunodeficiency viruses. | hiv-1 env gene encodes a multifunctional glycoprotein that is involved in virus infectivity, interactions between the virus and the host immune system, and phenotypic characteristics of virus isolates in culture. a number of env functions map by genetic analysis to v3, one of five hypervariable domains that compose the surface component of env gp120. v1 and v2 hypervariable domains of env also contribute to the phenotype of hiv-1, although relationships between v1 and v2 genotypes and biological ... | 1996 | 8844021 |
| inhibition of hiv-1 expression by hiv-2. | hiv-1 and hiv-2 are co-endemic in certain geographic areas. hiv-2 is more weakly pathogenic than hiv-1, and progression to aids occurs less frequently and over a longer period of time. recent epidemiologic studies suggest that individuals infected with hiv-2 have a lower risk of hiv-1 infection. both immune mechanisms and various modes of viral interference have been proposed to account for these results. our findings, described in this paper, suggest that hiv-2 inhibits hiv-1 replication. to st ... | 1995 | 8825754 |
| multiple immunizations with attenuated poxvirus hiv type 2 recombinants and subunit boosts required for protection of rhesus macaques. | vaccine protocols involving multiple immunizations with molecularly attenuated vaccinia virus (nyvac) or naturally attenuated canarypox virus (alvac) hiv-2 recombinants and subunit boosts have conferred longlasting protection against hiv-2 infection of macaques. similar complex protocols using hiv-1 nyvac and alvac recombinants and subunit boosts have provided cross-protection against hiv-2 challenge. here a simplified three-immunization regimen over 24 weeks was tested in 18 juvenile rhesus mac ... | 1996 | 8827214 |
| molecular cloning of the human immunodeficiency virus subtype 2 strain hiv-2uc2. | an infectious molecular clone was derived from the hiv-2uc2 isolate that previously was found to persistently infect and induce an aids-like disease syndrome in baboons. the molecularly cloned virus (hiv-2uc2mc) showed in vitro properties similar to those of the parental isolate with regard to t-cell tropism, cytopathicity, and the ability to infect primary baboon pbmc. nevertheless, when inoculated into two baboons, the cloned virus showed a limited ability to replicate in these animals. dna se ... | 1996 | 8806506 |
| evaluation of a new third generation anti-hiv-1/anti-hiv-2 assay with increased sensitivity for hiv-1 group o. | although the hiv-1 group o virus found in two persons of cameroonian origin has been described in 1990 (de leys et al., 1990), sera from group o infected individuals became available only recently. several studies showed that some of the anti-hiv-1/hiv-2 screening tests failed to detect all of these samples (loussert-ajaka et al., 1994; simon et al., 1994; schable et al., 1994; gürtler et al., 1995). in the current version of an anti-hiv-1/anti-hiv-2 screening assay, namely the vironostika hiv u ... | 1996 | 8844618 |
| human immunodeficiency virus (hiv) antigen testing to detect hiv infection in female sex workers in singapore. | human immunodeficiency virus (hiv) infection is characterised by seroconversion after a ¿window¿ period of 2 to 3 months. after this period antibodies are usually detectable by screening tests (enzyme immunoassay or particle agglutination) confirmed by western blot analysis. we studied 1000 newly enrolled female sex workers who had not been previously tested for hiv to assess the usefulness of hiv antigen testing to improve the efficacy of hiv infection detection. blood was taken at enrollment f ... | 1995 | 8849183 |
| conformational stability of dimeric hiv-1 and hiv-2 reverse transcriptases. | the dissociation of dimeric reverse transcriptase (rt) of the human immunodeficiency virus (hiv) types 1 and 2 has been investigated using acetonitrile as a dissociating agent. the equilibrium transitions were monitored by combining different approaches (fluorescence spectroscopy, polymerase activity assay, and size-exclusion hplc). the dissociation of rt induced a complete loss of polymerase activity and a 25% increase of the intrinsic fluorescence. it is fully reversible, and the midpoints of ... | 1995 | 8845359 |
| prevalence of blood-borne viruses among intravenous drug users and alcoholics in hiroshima, japan. | we investigated the prevalence of human immunodeficiency viruses-1 and 2 (hiv-1 and hiv-2), human t-lymphotropic virus type i and ii, hepatitis b virus (hbv), hepatitis c virus (hcv) and hepatitis d virus among intravenous drug users (ivdu) in hiroshima, japan, where little is known about their present levels. from june to december 1993, serum samples were collected from 47 ivdu and 98 alcoholics in hiroshima, japan, and examined for markers of virus infection. the prevalence of antibody to hcv ... | 1995 | 8845404 |
| hiv-1 gp41 selectively inhibits spontaneous cell proliferation of human cell lines and mitogen- and recall antigen-induced lymphocyte proliferation. | human immunodeficiency virus type 1 (hiv-1) transmembrane glycoprotein 41 (gp41) contains an immunosuppressive domain (env amino acids 583-599). previous studies by us and others using recombinant soluble gp41 (rsgp41; amino acids 539-684) and immunosuppressive peptide (1sp; a gp41 peptide, amino acids 583-599) have shown that hiv-1 gp41 by the immunosuppressive domain could bind to several proteins on human t, b and monocyte cell lines, and also to normal human peripheral blood mononuclear cell ... | 1995 | 8847089 |
| risk factor analysis and serological diagnosis of hiv-1/hiv-2 infection in a brazilian blood donor population: validation of the world health organization strategy for hiv testing. | to determine the relative prevalence of hiv-1 and hiv-2 and to evaluate the world health organization testing strategy for hiv diagnosis in a low-risk population in brazil. in addition, to assess risk factors for hiv infection. | 1996 | 8874631 |
| trends in hiv-1 and hiv-2 prevalence and risk factors in pregnant women in harare, zimbabwe. | the spread of the human immunodeficiency virus (hiv) and the resulting morbidity and mortality are major public health challenges with adverse social and economic implications. the pregnant population serves as an important marker of the extent of the problem in the sexually active low risk categorized population. furthermore, a high hiv prevalence among women of childbearing age contributes to neonatal and infant mortality through perinatal transmission and also a large number of uninfected chi ... | 1996 | 8868380 |
| human immunodeficiency virus (hiv) nef is an rna binding protein in cell-free systems. | the function of human immunodeficiency virus nef gene product has been much debated but the precise activity of this protein in the hiv replication cycle remains unknown. hiv-1 nef was obtained as a fusion protein with maltose binding protein (mbf), purified by amylose column chromatography and separated from mbp by cleavage with factor xa. purified hiv-1 nef protein, but not the fusion protein mbp-nef, binds to rna in vitro as tested by three different assays, radioactive or non-radioactive. no ... | 1996 | 8876644 |
| specific inhibition of human immunodeficiency virus type 1 reverse transcriptase mediated by soulattrolide, a coumarin isolated from the latex of calophyllum teysmannii. | soulattrolide (1), a coumarin isolated from calophyllum teysmannii latex, was found to be a potent inhibitor of hiv-1 reverse transcriptase (rt) with an ic50 of 0.34 microm. inhibition was remarkably specific, with no appreciable activity being observed toward hiv-2 rt, amv rt, rna polymerase, or dna polymerases alpha or beta. | 1996 | 8864237 |
| salivary testing for human immunodeficiency virus type 1 infection in children born to infected mothers in sao paulo, brazil. the sao paulo collaborative study for vertical transmission of hiv-1. | to validate a method for salivary testing for hiv infection in children older than 12 months. | 1996 | 8878222 |
| the v3 domain of sivmac251 gp120 contains a linear neutralizing epitope. | antisera to 21 synthetic peptides containing hydrophilic sequences of simian immunodeficiency virus strain mac251 (sivmac251) gp120 and gp32 were tested for the ability to neutralize sivmac251. goat antisera raised to peptides sp-1 and sp-1v containing the carboxy-terminal portion of the v3 domain of sivmac251 gp120 between amino acids 327 and 339 inhibited syncytium formation (90% inhibition at a 1/1024 dilution) and cell killing of cemx174 cells by sivmac251 (50%) inhibition of cell killing at ... | 1996 | 8874502 |
| clinico-epidemiological patterns of hiv infection in std patients in ibadan. | the hiv-seropositive subjects identified among the std clinic patients seen at a special treatment clinic between 1989 and 1990 were studied to determine the epidemiological and clinical trends of hiv infection in these patients, and to demonstrate any association between the stds and hiv- seropositivity. thirty-seven out of the 581 patients investigated have been confirmed hiv-seropositive by western bolt. the prevalence of hiv infection was 6.4%. anti-hiv-1 antibody prevalence (3.6%) was highe ... | 1995 | 8886145 |
| development of hiv vectors for anti-hiv gene therapy. | current gene therapy protocols for hiv infection use transfection or murine retrovirus mediated transfer of antiviral genes into cd4+ t cells or cd34+ progenitor cells ex vivo, followed by infusion of the gene altered cells into autologous or syngeneic/allogeneic recipients. while these studies are essential for safety and feasibility testing, several limitations remain: long-term reconstitution of the immune system is not effected for lack of access to the macrophage reservoir or the pluripoten ... | 1996 | 8876146 |
| t cell apoptosis in human immunodeficiency virus type 2- and simian immunodeficiency virus-infected macaques. | recent evidence suggests that t cell apoptosis could be involved in the pathogenesis of hiv infection. in addition, lymphocyte apoptosis has been described in siv-infected macaques that developed simian aids. to investigate further the role of apoptosis in aids pathogenesis, we studied lymphocytes of hiv-2-infected cynomolgus macaques that did not develop simian aids. we compared apoptosis of lymphocytes from animals infected with non-pathogenic hiv-2 to that in macaques infected with pathogenic ... | 1996 | 8887474 |
| rapid sequon evolution in human immunodeficiency virus type 1 relative to human immunodeficiency virus type 2. | | 1996 | 8891118 |
| development of a chronically catheterized maternal-fetal macaque model to study in utero mother-to-fetus hiv transmission: a preliminary report. | the lack of a representative animal model that permits frequent in utero fetal blood sampling is a major limiting factor for the study of maternal-fetal hiv transmission. therefore, we have developed a maternal-fetal virus infection model using chronically catheterized macaques to simultaneously study the time-course of viral infection in the mother and the response of the fetus to maternal hiv infection. pregnant macaques were infected with 10(3) infectious units of hiv-2(287); every 3 days blo ... | 1996 | 8892043 |
| infectivities of human and other primate lentiviruses are activated by desialylation of the virion surface. | the envelope protein, gp120, of human immunodeficiency virus type 1 (hiv-1) is heavily glycosylated and sialylated. the heavy sialylation greatly affects the physical properties of the protein, as it resolves into a wide acidic ph range despite the basic pi value predicted for its polypeptide backbone (b. s. stein and e. g. engleman, j. biol. chem. 265:2640-2649, 1990). however, the functional significance of the heavy sialylation remains elusive. here, we show that desialylation of hiv-1 with n ... | 1996 | 8892864 |
| inhibition of human immunodeficiency virus type 1 and type 2 tat function by transdominant tat protein localized to both the nucleus and cytoplasm. | we introduced various mutations into the activation and rna binding domains of human immunodeficiency virus type 1 (hiv-1) tat in order to develop a novel and potent transdominant tat protein and to characterize its mechanism of action. the different mutant tat proteins were characterized for their abilities to activate the hiv ltr and inhibit the function of wild-type tat in trans. a tat protein containing a deletion of the basic domain (tat(delta)49-57) localized exclusively to the cytoplasm o ... | 1996 | 8892930 |
| possible role of the v3 domain of gp120 in resistance to an amphotericin b derivative (ms8209) blocking human immunodeficiency virus entry. | ms8209, an amphotericin b derivative blocking human immunodeficiency virus type 1 (hiv-1) entry after cd4 binding, neutralized the hiv-2 strains eho and rod10 but not rod(cem). in the v3 domain of gp120, rod(cem) differed from rod10 at two positions (a threonine instead of an isoleucine at position 312 and an arginine instead of a glutamine at position 329), and drug resistance was conferred to hiv-1 by substitution of the rod(cem) v3 but not the rod10 v3. v3 mutations may prevent the interactio ... | 1996 | 8892962 |
| prevalence of hiv-1, hiv-2 and htlv antibody, in fortaleza, ceara, brazil, 1993-1994. | to evaluate the respective part of hiv-1, hiv-2, and human t lymphotropic virus (htlv) infection in fortaleza, the principal city of the ceara state (northeast of brazil), a cross-sectional seroepidemiological survey was conducted from july 1993 to february 1994 in 6 selected groups: pregnant women, tuberculosis (tb) patients, sexually transmitted disease (std) patients, female and male commercial sex workers (csws) and prisoners. sera were screened by mixt hiv-1/hiv-2 commercial enzyme immunoas ... | 1996 | 8894828 |
| protection against human immunodeficiency virus type 2 and simian immunodeficiency virus in macaques vaccinated against human immunodeficiency virus type 2. | | 1996 | 8882330 |
| binding properties of human immunodeficiency virus type-2 (hiv-2) rna corresponding to the packaging signal to its nucleocapsid protein. | the nucleocapsid (nc) protein of human immunodeficiency virus type-1 (hiv-1) contains two zinc finger motifs (zfms), and binds specifically to the packaging signal which is located in the 5' leader sequence of the viral genomic rna between the first splice donor and the gag initiator codon (aug). in this study, we analyzed the specificity of the binding of the corresponding region of hiv-2 (region 3) to its nc protein (ncp8), by performing a competitive ultraviolet (uv) cross-linking assay using ... | 1996 | 8886267 |
| evaluation of chiron hiv-1/hiv-2 recombinant immunoblot assay. | in a study to determine the reliability, sensitivity, and specificity of the chiron riba hiv-1/hiv-2 strip immunoblot assay (riba hiv-1/2 sia) for confirmation of human immunodeficiency virus type 1 (hiv-1) and hiv-2 antibodies, 1,263 serum samples from various populations in the united states, caribbean, africa, india, and thailand were evaluated by riba hiv-1/2 sia, and the results were compared with those obtained by an hiv-1 western blot (immunoblot) assay. all sera were tested by hiv enzyme ... | 1996 | 8897158 |
| native oligodeoxynucleotides specifically active against human immunodeficiency virus type 1 in vitro: a g-quartet-driven effect? | among a series of unmodified phosphodiester (po)-oligodeoxynucleotides (po-odns) complementary to some of the human immunodeficiency virus type 1 (hiv-1) regulatory genes, several po-odn sequences complementary to the vpr gene (po-odns-a-vpr, where a-vpr is the antisense vpr sequence) emerged as potent inhibitors (at concentrations of 0.8 to 3.3 microm) of hiv-1 multiplication in de novo infected mt-4 cells, while they showed no cytotoxicity for uninfected cells at concentrations up to 100 micro ... | 1996 | 8878576 |
| immunogenicity and protective efficacy of a human immunodeficiency virus type 2 recombinant canarypox (alvac) vaccine candidate in cynomolgus monkeys. | the efficacy of a recombinant human immunodeficiency virus (hiv) type 2 canarypox (alvac hiv-2) vaccine candidate given alone or in combination with hiv-2 envelope gp125 or hiv-2 v3 synthetic peptides was investigated in 14 cynomolgus monkeys. high antibody titers to hiv-2 gp125 were demonstrated in monkeys given booster immunizations with gp125. neutralizing antibody titers were low (< or = 20) in all monkeys except 2. significant lymphocyte proliferative responses to killed hiv-2 virions were ... | 1996 | 8896498 |
| receptor interference mediated by the envelope glycoproteins of various hiv-1 and hiv-2 isolates. | the envelope glycoprotein of human immunodeficiency virus type 1 (hiv-1) plays a major role in the down-regulation of its receptor, cd4. this down-regulation, at least in part, is caused by the formation of gp160-cd4 intracellular complexes which fail to transport out of the endoplasmic reticulum (er). in this report, we have evaluated the ability of envelope glycoproteins from various isolates to block cd4 transport within the endoplasmic reticulum. using a recombinant vaccinia virus expression ... | 1996 | 8896248 |
| chemical trapping of ternary complexes of human immunodeficiency virus type 1 integrase, divalent metal, and dna substrates containing an abasic site. implications for the role of lysine 136 in dna binding. | we report a novel assay for monitoring the dna binding of human immunodeficiency virus type 1 (hiv-1) integrase and the effect of cofactors and inhibitors. the assay uses depurinated oligonucleotides that can form a schiff base between the aldehydic abasic site and a nearby enzyme lysine epsilon-amino group which can subsequently be trapped by reduction with sodium borohydride. chemically depurinated duplex substrates representing the u5 end of the hiv-1 dna were initially used. we next substitu ... | 1996 | 8910309 |
| severe illness in african children with diarrhoea: implications for case management strategies. | to identify clinical disorders associated with severe illness in african children with diarrhoea, we studied a group of under-5-year-olds with diarrhoea who had been brought to a large public hospital in central cote d'ivoire. the general condition of children with diarrhoea was assessed and classified according to criteria recommended by who, and then used as a nonspecific indicator of severity. of the 264 children with diarrhoea who were enrolled in the study, 196 had nonsevere illness and 68 ... | 1995 | 8907771 |
| inhibition of the human immunodeficiency virus type 1 integrase by guanosine quartet structures. | an oligonucleotide (t30177) composed entirely of deoxyguanosine and thymidine has previously been shown to fold upon itself in the presence of potassium into a highly stable four-stranded dna structure containing two stacked deoxyguanosine quartets (g4s). t30177 also protects host cells from the cytopathic effects of human immunodeficiency virus type 1 (hiv-1). we report that this g4 oligonucleotide is the most potent inhibitor of hiv-1 integrase identified to date, with ic50 values in the nanom ... | 1996 | 8901518 |
| nuclear import and cell cycle arrest functions of the hiv-1 vpr protein are encoded by two separate genes in hiv-2/siv(sm). | the vpr genes of human and simian immunodeficiency viruses (hiv/siv) encode proteins which are packaged in the virus particle. hiv-1 vpr has been shown to mediate the nuclear import of viral reverse transcription complexes in non-dividing target cells (e.g. terminally differentiated macrophages), and to alter the cell cycle and proliferation status of the infected host cell. members of the hiv-2/siv(sm) group encode, in addition to vpr, a related protein called vpx. because these two proteins sh ... | 1996 | 8947037 |
| serial cd4 and cd8 t-lymphocyte counts and associated mortality in an hiv-2-infected population in guinea-bissau. | in an urban community in guinea-bissau, we followed a cohort of human immunodeficiency virus type 2 (hiv-2) seropositive individuals (n = 47) and seronegative controls (n = 82). t-lymphocyte subset determinations were done in 1988, 1990, and 1992. serial determinations of cd4 percentages, cd8 percentages, and cd4/cd8 ratios for the same individual were stable for 31 seropositive and 51 seronegative individuals with repeated measurements. we found no significant differences in the changes during ... | 1996 | 8948374 |
| multicenter evaluation of new double-antigen sandwich enzyme immunoassay for measurement of anti-human immunodeficiency virus type 1 and type 2 antibodies. | a new enzyme immunoassay (eia), the cobas core anti-hiv-1/hiv-2 eia dags (also referred to as roche dags), for the detection of antibodies to human immunodeficiency virus type 1 (hiv-1) and hiv-2 was evaluated in four centers. the assay is based on the double-antigen sandwich (dags) format, which enables the detection of all classes of antibodies. the antigens consist of recombinant proteins in their native conformation and of synthetic peptides. of a total of 5,836 negative serum samples, inclu ... | 1996 | 8904428 |
| distinct quasi-species in the blood and the brain of an hiv-2-infected individual. | sequences of the hiv-2 envelope c2-c3 region were obtained after direct pcr amplification of proviral dna from the brain and peripheral blood mononuclear cells of an hiv-2-infected aids patient. tissue-specific sequences confirmed previous observations that hiv-2 is indeed present in the central nervous system of infected individuals. distinct but related quasi-species were present in these two different tissues of the same individual. residues at position 18 and 19 of the v3 loop and overall ch ... | 1996 | 8955063 |
| activation of pak by hiv and siv nef: importance for aids in rhesus macaques. | the primate lentiviruses, human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2) and simian immunodeficiency virus (siv), encode a conserved accessory gene product, nef. in vivo, nef is important for the maintenance of high virus loads and progression to aids in siv-infected adult rhesus macaques. in tissue culture cells expressing nef, this viral protein interacts with a cellular serine kinase, designated nef-associated kinase. | 1996 | 8939608 |
| antiviral activity and mechanism of action of calanolide a against the human immunodeficiency virus type-1. | calanolide a, recently discovered in extracts from the tropical rainforest tree, calophyllum lanigerum, is a novel inhibitor of the human immunodeficiency virus (hiv) type 1. the compound is essentially inactive against strains of the less common hiv type 2. the present study focused on the further characterization of the selective antiviral activity and mechanism of action of calanolide a. the compound inhibited a wide variety of laboratory strains of hiv type 1, with ec50 values ranging from 0 ... | 1996 | 8930167 |
| baboon endogenous virus evolution and ecology. | cross-species transmission of retroviruses among primates has recently been recognized as the source of the current epidemics of hiv-1, hiv-2 and human t cell leukemia virus type 1 (htlv-1). the distribution of baboon endogenous virus among non-human primates resembles that of exogenous viruses and appears to be a consequence of different primate species sharing the same habitat. | 1996 | 8950816 |
| hiv-2 infection in 12 european residents: virus characteristics and disease progression. | to assess the disease progression rate among 12 hiv-2-infected west european residents (nine of west african descent), compared with the disease progression rate among hiv-1-infected individuals of the same population, and the characteristics of the hiv-2 strains involved. | 1996 | 8970685 |
| summary of track c: epidemiology and public health. | aim: to review track c on epidemiology and public health. descriptive epidemiology: recent trends in the descriptive epidemiology are reported, for example, the rapid spread of hiv in certain asian countries and the more precise insights in the spread thanks to subtyping of hiv-1 (and hiv-2). transmission: there is now ample evidence that sexually transmitted diseases enhance the rate of transmission. viral load in the plasma of the mother is highly predictive for perinatal transmission. progres ... | 1996 | 8970718 |
| the human immunodeficiency virus (hiv) type 2 envelope protein is a functional complement to hiv type 1 vpu that enhances particle release of heterologous retroviruses. | we have recently shown that the envelope glycoprotein of the rod10 isolate of human immunodeficiency virus type 2 (hiv-2) has the ability to positively regulate hiv-2 viral particle release. the activity provided by the rod10 env was remarkably similar to that of the hiv-1 vpu protein, thus raising the possibility that the two proteins act in a related fashion. we now show that the rod10 env can functionally replace vpu to enhance the rate of hiv-1 particle release. when provided in trans, both ... | 1996 | 8970948 |
| specific cleavage sites of nef proteins from human immunodeficiency virus types 1 and 2 for the viral proteases. | human immunodeficiency virus type 2 (hiv-2) nef is proteolytically cleaved by the hiv-2-encoded protease. the proteolysis is not influenced by the absence or presence of the n-terminal myristoylation. the main cleavage site is located between residues 39 and 40, suggesting a protease recognition sequence, ggey-sqfq. as observed previously for nef protein from hiv-1, a large, stable core domain with an apparent molecular mass of 30 kda is produced by the proteolytic activity. cleavage of nef from ... | 1996 | 8971042 |
| novel l-lyxo and 5'-deoxy-5'-modified tsao-t analogs: synthesis and anti-hiv-1 activity. | novel l-lyxo-tsao-t analogs with an inverted configuration at the c-4'-position of the sugar moiety and 5'-deoxy-5'-modified tsao-t derivatives have been prepared and evaluated for their inhibitory effect on human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) replication in cell culture. none of the compounds showed marked antiviral efficacy. the inactivity of the tsao-t derivatives may most likely be explained by either their different 4'-configuration or their different chemical str ... | 1996 | 8955510 |
| inhibition of bovine immunodeficiency virus by anti-hiv-1 compounds in a cell culture-based assay. | the bovine immunodeficiency virus (biv) and human immunodeficiency virus types 1 and 2 (hiv-1 and -2) are members of the lentivirus genus of retroviruses. although dna sequences of these viruses have diverged considerably, the biv genome organization, function of structural and regulatory genes, and replication cycle are very similar to that of hiv-1, making biv a potentially useful model to study compounds with anti-hiv-1 activity. a cell culture-based antiviral assay was developed to test comp ... | 1996 | 8955850 |
| inhibition of human immunodeficiency virus replication by the sulfonated stilbene dye resobene. | the anti-hiv sulfonated dye, resobene, was found to be a potent inhibitor of the attachment of hiv to target cells, the fusion of envelope- and cd4-expressing cells, and the cell-to-cell transmission of virus. resobene inhibited the infection of phenotypically distinct, established human cell lines and fresh human peripheral blood lymphocytes and macrophages by laboratory-derived isolates of human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2), and a panel of biologically diverse prima ... | 1996 | 8955852 |
| bile pigments as hiv-1 protease inhibitors and their effects on hiv-1 viral maturation and infectivity in vitro. | using recently developed molecular-shape description algorithms, we searched the available chemical directory for known compounds similar in shape to the potent hiv-1 protease inhibitor merck l-700,417; 15 compounds most similar in shape to the inhibitor were selected for testing in vitro. four of these inhibited the protease at 100 microm or less and the most active of the four were the naturally occurring pigments biliverdin and bilirubin. biliverdin and bilirubin inhibited recombinant hiv-1 p ... | 1996 | 8973584 |
| cdc42 and rac1 are implicated in the activation of the nef-associated kinase and replication of hiv-1. | the negative factor (nef) of human and simian immunodeficiency viruses (hiv-1, hiv-2 and siv) is required for high levels of viremia and progression to aids. additionally, nef leads to cellular activation, increased viral infectivity and decreased expression of cd4 on the cell surface. previously, we and others demonstrated that nef associates with a cellular serine kinase (nak) activity. recently, it was demonstrated that nak bears structural and functional similarity to p21-activated kinases ( ... | 1996 | 8994833 |
| the role of eukaryotic subtilisin-like endoproteases for the activation of human immunodeficiency virus glycoproteins in natural host cells. | proteolytic activation of the precursor envelope glycoproteins gp160 of human immunodeficiency virus type 1 (hiv-1) and gp140 of hiv-2, a prerequisite for viral infection, results in the formation of gp120/gp41 and gp125/gp36, respectively. cleavage is mediated by cellular proteases. furin, a member of the eukaryotic subtilisin family, has been shown to be an activating protease for hiv. here, we compared the presence of furin and other mammalian subtilisins in lymphatic cells and tissues. north ... | 1997 | 8995623 |
| the cd4-independent tropism of human immunodeficiency virus type 2 involves several regions of the envelope protein and correlates with a reduced activation threshold for envelope-mediated fusion. | several human immunodeficiency virus type 2 (hiv-2) strains have been shown to infect some cd4-negative cell lines (p. r. clapham, a. mcknight, and r. a. weiss, j. virol. 66:3531-3537, 1992). using molecular clones of hiv-2 with a cd4-independent tropism, we have identified critical amino acid residues in the envelope protein which are required for cd4-independent infection. mutations located immediately upstream of a proposed coiled coil domain in the transmembrane protein (a526t or i528m) and ... | 1997 | 8995671 |
| inhibition of human immunodeficiency virus fusion by a monoclonal antibody to a coreceptor (cxcr4) is both cell type and virus strain dependent. | cxcr4 (also termed fusin, lestr, or humstr) is a member of the g-protein-coupled chemokine receptor family with seven membrane-spanning domains. cxcr4 acts as a coreceptor for syncytium-inducing human immunodeficiency virus type 1 (hiv-1) strains, conferring entry into cd4+ cells. we show here that a novel mouse monoclonal antibody (12g5) that recognizes cxcr4 blocked cell-to-cell fusion and cell free-virus infection of cxcr4+ cd4+ rd rhabdomyosarcoma cells by seven hiv-1 and hiv-2 strains that ... | 1997 | 8995702 |
| cd8+ t cells from hiv type 1-seronegative individuals suppress virus replication in acutely infected cells. | cd8+ lymphocytes (cd8 cells) have been shown to inhibit replication of the human immunodeficiency virus (hiv) in vitro when cocultured with hiv-infected cd4+ lymphocytes (cd4 cells). this suppressive effect on hiv replication in experimentally infected cd4 cells has so far been demonstrated only for cd8 cells from hiv-seropositive individuals. in the present study we have investigated if cd8 cells from hiv-negative individuals can also suppress hiv replication in experimentally infected cd4 cell ... | 1997 | 8989430 |
| the neutralization relationship of hiv type 1, hiv type 2, and sivcpz is reflected in the genetic diversity that distinguishes them. | neutralizing antibody (na) patterns in the sera of individuals naturally infected with human immunodeficiency virus (hiv) type 1, hiv-2, and the simian immunodeficiency virus (sivcpz) to their homologous and heterologous isolates were determined in a peripheral blood mononuclear cell-based neutralization assay. we examined the role of the v3 loop of hiv-1 and sivcpz in neutralization and the cross-reactivities among them. cross-neutralization by sera of humans and chimpanzees naturally infected, ... | 1997 | 8989422 |
| human plasmatic apolipoprotein h binds human immunodeficiency virus type 1 and type 2 proteins. | apolipoprotein h (apo h), isolated from human plasma albumin solution, was shown to capture hiv-1-related antigens from antigen-positive sera (hiv-1 ag+) of aids patients, by using hiv-1-specific polyclonal antibodies. in an enzyme-linked immunosorbent assay and ligand blot and dot assays, apo h was able to bind recombinant retroviral hiv antigens, especially gag proteins p18 of hiv-1, p26 of hiv-2, and env gp160 of hiv-1. binding was shown to be ph and nacl dependent, with an optimum at acidic ... | 1997 | 8989432 |
| human immunodeficiency virus risk behavior among white and asian/pacific islander high school students in the united states: does culture make a difference? | this article analyzes sexual behavior among white and asian/pacific islander (api) adolescents, to determine the risk for human immunodeficiency virus (hiv) transmission from a multicultural point of view. | 1997 | 9007662 |
| hiv antigens and t-cell receptor variable beta chain families. | the authors investigated whether the human immunodeficiency virus (hiv) has restrictive effects on the variable region of the beta chain (v beta) of the t-cell antigen receptor (tcr), by in vitro cultivation of non-hiv-infected peripheral blood lymphocytes with one of six hiv antigens or heat-inactivated whole virus (hiv-hi). resting and blastic cd4+ and cd8- cells were assessed with 3-colour cytofluorometry and monoclonal antibodies to various v beta families/subfamilies. the v beta families af ... | 1997 | 9010504 |
| [occurrence of false positives in tests with synthetic peptides for the analysis of antibodies against the human immunodeficiency virus type 2 (hiv-2) in brazilian patients infected with the human immunodeficiency virus type 1 (hiv-1)]. | | 1996 | 9011891 |
| impact of human immunodeficiency virus infection on abdominal tuberculosis in western india. | we studied the seroprevalence of human immunodeficiency virus infection in patients with pulmonary tuberculosis and abdominal tuberculosis. we also assessed the clinical characteristics, risk factors, tuberculin status, site, and response to therapy of abdominal tuberculosis in human immunodeficiency virus (hiv)-seropositive and hiv-seronegative patients. volunteer blood donors (n = 8,395), patients with pulmonary tuberculosis (n = 387), and patients with abdominal tuberculosis (n = 108) were sc ... | 1997 | 9013351 |
| cd8+ cells from asymptomatic human immunodeficiency virus-infected individuals suppress superinfection of their peripheral blood mononuclear cells. | most human immunodeficiency virus (hiv)-infected individuals show evidence of infection by only one strain of the virus despite possible frequent contact with multiple strains. the reason(s) for the emergence of a dominant strain of virus in hiv-infected people and the mechanism(s) which prevent other strains from establishing an infection is not known. in the present study, we demonstrate that peripheral blood mononuclear cells (pbmc) of asymptomatic hiv-infected individuals can resist producti ... | 1996 | 9000085 |
| [course of hiv2 seroprevalence at the national hospital of niamey (niger)]. | about the 25,368 serological tests done among the different groups of the population at the biological laboratory of the national hospital of niamey from march 1987 to may 1990, the author studied the seroprevalence evolution of the infection hiv2. a regular fall for the hiv2 appeared in this period. the author tries to explain this fall of the hiv2 in a country newly infected by the hiv by the lower infectivity of the hiv2 and/or a failure to adjust of this virus in niger. | 1996 | 8998417 |
| stavudine selectively induces apoptosis in hiv type 1-infected cells. | we evaluated the cytotoxic effects of various human immunodeficiency virus (hiv-1) reverse transcriptase inhibitors (zidovudine, didanosine, zalcitabine, stavudine, and nevirapine) on hiv-1-infected and uninfected t cell lines. among the compounds, only stavudine (not the others) proved to be more cytotoxic to molt-4/iiib cells (molt-4 cells chronically infected with hiv-1) than to uninfected molt-4 cells. its 50% cytotoxic concentrations were 59.8 and 2.2 microm for molt-4 and molt-4/iiib cells ... | 1997 | 9007205 |
| srr-sb3, a disulfide-containing macrolide that inhibits a late stage of the replicative cycle of human immunodeficiency virus. | from a series of macrocyclic diamides possessing the disulfide linkage, only srr-sb3, a compound that complexes with zinc, was found to inhibit human immunodeficiency virus type 1 (hiv-1; strain iiib) replication at a concentration of 1.8 to 6.5 micrograms/ml in mt-4, cem, and peripheral blood mononuclear cells. srr-sb3 was toxic to mt-4 cells at a concentration of 15.9 micrograms/ml, resulting in a selectivity index of 9 in these cells. this macrolide was also effective against various other hi ... | 1997 | 9021177 |
| polyanion inhibitors of human immunodeficiency virus and other viruses. 5. telomerized anionic surfactants derived from amino acids. | omega-acryloyl anionic surfactants, whose polar heads are derived from amino acids, have been telomerized to prepare polyanions of a predetermined molecular weight. the main goal of this study was to verify whether the antiviral activity is influenced by the degree of polymerization of the polyanions. the oligomeric polyanions were evaluated for their activity against human immunodeficiency virus (hiv-1 or hiv-2) and various other rna and dna viruses. with regard to their anti-hiv activity, a mi ... | 1997 | 9022800 |
| diarylsulfones, a novel class of human immunodeficiency virus type 1 integrase inhibitors. | a majority of reported human immunodeficiency virus type 1 integrase (hiv-1 in) inhibitors are polyhydroxylated aromatic compounds containing two phenyl rings separated by aliphatic or aromatic linkers. most inhibitors possessing a catechol moiety exhibit considerable toxicity in cellular assays. in an effort to identify nonhydroxylated analogs, a series of aromatic sulfones were tested for their ability to inhibit the 3' processing and strand transfer steps that are necessary for hiv replicatio ... | 1997 | 9021196 |
| prevention of simian immunodeficiency virus, sivsm, or hiv-2 infection in cynomolgus monkeys by pre- and postexposure administration of bea-005. | to study the possibilities and limitations of postexposure treatment to prevent the establishment of infection after accidental exposure to hiv. | 1997 | 9030361 |
| novel 3'-c/n-substituted 2',3'-beta-d-dideoxynucleosides as potential chemotherapeutic agents. 1. thymidine derivatives: synthesis, structure, and broad spectrum antiviral properties. | a synthetic scheme for the 3'-oxime derivatives 3e, 5e, 5z, 7e and 7z of 1-(2,3-dideoxy-beta-d-glycero-pentofuranosyl)thymine and for 1-(2,3-dideoxy-3-nitro-beta-d-erythro-pentofuranosyl)-thymine (10) has been developed starting from appropriately 5'-protected 3'-ketothymidine. x-ray analysis showed that 3'-n-hydroxyimino 3e and 3'-n-methoxyimino 5z derivatives have close molecular conformations: anti about the n1-c1' bond, and gauche+ about the c4'-c5' exocyclic bond. their sugar conformations ... | 1997 | 9046339 |
| new anti-human immunodeficiency virus immunoblot assays resolve nonspecific western blot results. | two new anti-human immunodeficiency virus type 1 and 2 (hiv-1/2) immunoblot assays, which use recombinant and synthetic antigens for antibody detection have become available. these assays might be able to resolve indeterminate anti-hiv western blot results. | 1997 | 9051095 |
| inhibition of multiple phases of human immunodeficiency virus type 1 replication by a dithiane compound that attacks the conserved zinc fingers of retroviral nucleocapsid proteins. | the human immunodeficiency virus type 1 (hiv-1) nucleocapsid p7 protein contains two retrovirus-type zinc finger domains that are required for multiple phases of viral replication. chelating residues (three cys residues and one his residue) of the domains are absolutely conserved among all strains of hiv-1 and other retroviruses, and mutations in these residues in noninfectious virions. these properties establish the zinc finger domains as logical targets for antiviral chemotherapy. selected dit ... | 1997 | 9021201 |
| evidence for the association of nef protein with hiv-2 virions. | hiv-nef protein supports viral infectivity prior to proviral integration. this requires nef to be present before the expression of viral genes and suggests its delivery as part of the virion. we report here that the nef proteins of hiv-2-hom and hiv-2-rod are associated with the virion. after the separation of pelleted virus in a 20-60% sucrose density gradient, both proteins cosedimented with the virion-associated reverse transcriptase (rt) activity at a density characteristic of retroviral par ... | 1996 | 9029783 |
| human immunodeficiency virus type 2 preintegration complexes: activities in vitro and response to inhibitors. | we have established an assay for the function of preintegration complexes (pics) of human immunodeficiency virus type 2 (hiv-2) to investigate the integration mechanism and to develop additional methods for screening candidate integration inhibitors. we partially purified hiv-2 pics and found that they were competent to integrate viral cdna into target dna in vitro. analysis of the structure of integration products on southern blots revealed forms consistent with those expected for authentic int ... | 1997 | 9060709 |
| hiv-2 prevalence in uttar pradesh. | serum samples collected since 1989 with various patterns of reactivity for human immunodeficiency virus (hiv)-1, on the basis of screening elisa and confirmatory western blot (wb) test, were subjected to the detection of hiv-2 infection based on screening dot immunoassay and confirmatory wb for hiv-2. significant prevalence of hiv-2 infection was (37.03%) among sera reactive for hiv-1 by elisa but indeterminate by western blot, compared with sera reactive for hiv-1 by elisa and wb (3.29%) or neg ... | 1996 | 9062036 |
| association of tat with purified hiv-1 and hiv-2 transcription preinitiation complexes. | the hiv-1 (human immunodeficiency virus type 1) and hiv-2 tat proteins increase the level of transcription from their corresponding long terminal repeats. tat activates transcription likely by interaction with components of the transcriptional initiation and elongation complexes during different stages of the transcription reaction. in the current study, two approaches were used to address the sites at which tat becomes stably associated with the hiv transcription complex. first, we isolated col ... | 1997 | 9054383 |
| detection of human immunodeficiency virus type 1 and type 2 antibodies by a new automated microparticle immunoassay axsym hiv-1/hiv-2. | a new automated microparticle enzyme immunoassay (meia) for the axsym instrument developed recently by abbott laboratories was compared with two established assays, i.e. hiv-1/hiv-2 3rd gen. plus eia (abbott, delkenheim, frg) and wellcozyme hiv 1 + 2 (murex diagnostics, dartford, england) devised for the detection of human immunodeficiency virus type 1 (hiv-1) and hiv-2 antibodies. a total of 7293 serum samples were tested by the axsym hiv-1/hiv-2. the test panel included seroconversions (n = 22 ... | 1997 | 9015284 |
| human immunodeficiency virus strains differ in their ability to infect cd4+ cells expressing the rat homolog of cxcr-4 (fusin). | a clade b strain of human immunodeficiency virus type 1 (hiv-1(lai)) could infect cd4+ cells expressing human cxcr-4 (fusin) or its rat homolog with similar efficacy. by contrast, cells expressing rat cxcr-4 were not permissive to hiv-1(ndk) (clade d), hiv-2(rod), or hiv-1(lai) with chimeric envelope protein gp120 bearing the v3 domain from hiv-1(ndk). the reciprocal chimeric gp120 (hiv-1(ndk) with v3 from hiv-1(lai)) could mediate infection of cells expressing either human or rat cxcr-4. geneti ... | 1997 | 9060691 |
| solution conformation of an immunogenic peptide derived from the principal neutralizing determinant of the hiv-2 envelope glycoprotein gp125. | the conformational preferences of a number of peptides with sequences related to the envelope glycoproteins of hiv-1 have been investigated in the past few years. similar studies have not been made for hiv-2, which is a distinct virus with similar physiological effects to those of hiv-1. the discovery of common structural features would be a promising route to the design of immunogens for generally effective hiv vaccines. we present the results of an nmr conformational study of a sequence derivi ... | 1996 | 9079375 |
| physical interactions between ets and nf-kappab/nfat proteins play an important role in their cooperative activation of the human immunodeficiency virus enhancer in t cells. | the transcriptional regulatory elements of many inducible t-cell genes contain adjacent or overlapping binding sites for the ets and nf-kappab/nfat families of transcription factors. similar arrays of functionally important nf-kappab/nfat and ets binding sites are present in the transcriptional enhancers of human immunodeficiency viruses types 1 and 2 (hiv-1 and hiv-2), suggesting that this pattern of nuclear protein binding sites reflects an evolutionarily conserved mechanism for regulating ind ... | 1997 | 9094628 |
| human immunodeficiency virus type 2 (hiv-2) seroprevalence and characterization of a distinct hiv-2 genetic subtype from the natural range of simian immunodeficiency virus-infected sooty mangabeys. | the extent of zoonotic infections in rural sierra leone, where both feral and pet sooty mangabeys harbor divergent members of the human immunodeficiency virus type 2 (hiv-2)-sooty mangabey simian immunodeficiency virus (sivsm) family, was tested in blood samples collected from 9,309 human subjects in 1993. using hiv-1- and hiv-2-specific enzyme immunoassays and confirmatory western blot analysis to test for antibodies to sivsm-related lentiviruses, we found only nine subjects (0.096%) who tested ... | 1997 | 9094672 |
| location of cis-acting signals important for rna encapsidation in the leader sequence of human immunodeficiency virus type 2. | we used a series of deletion mutations in the untranslated leader region of human immunodeficiency virus type 2 (hiv-2) to seek cis-acting packaging signals. sequences between the 5' major splice donor and the gag initiation codon, where such signals have been identified in hiv-1, appear to make a measurable but very minor contribution to genomic rna packaging, and deletions here had little effect on viral replication in vitro. immediately 5' to the splice donor, two regions were identified whic ... | 1997 | 9094696 |
| human submandibular saliva specifically inhibits hiv type 1. | studies from a number of laboratories have shown the presence of factor(s) in whole, parotid, and submandibular human saliva capable of inhibiting hiv-1 infectivity in vitro. data from our laboratory suggested that the level of anti-hiv-1 activity is higher in submandibular than parotid or whole saliva. previous results obtained with pooled submandibular saliva from seronegative individuals included a filtration step following saliva-virus interaction. in this article, we present data on the hiv ... | 1997 | 9075477 |
| probing interactions between viral dna and human immunodeficiency virus type 1 integrase using dinucleotides. | retroviral integrases are essential for viral replication and represent an attractive chemotherapeutic target. in the current study, we demonstrated the activity of micromolar concentrations of dinucleotides against human immunodeficiency virus type 1 (hiv-1), hiv type 2 (hiv-2), simian immunodeficiency virus, and feline immunodeficiency virus integrases. the structure-activity relationship indicates that 5'-phosphorylation enhances potency and that phosphodiester and sugar modifications affect ... | 1997 | 9106620 |
| genetic variation in human immunodeficiency virus type 2: identification of a unique variant from human plasma. | | 1997 | 9075481 |
| human immunodeficiency virus (hiv)-resistant cd4+ ut-7 megakaryocytic human cell line becomes highly hiv-1 and hiv-2 susceptible upon cxcr4 transfection: induction of cell differentiation by hiv-1 infection. | recent findings have shown that the expression of the seven trans-membrane g-protein-coupled cxcr4 (the receptor for the stromal cell-derived factor [sdf]-1 chemokine) is necessary for the entry of t-lymphotropic human immunodeficiency virus (hiv) strains, acting as a coreceptor of the cd4 molecule. in the human system, the role of cxcr4 in hiv infection has been determined through env-mediated cell fusion assays and confirmed by blocking viral entry in cd4+/cxcr4+ cells by sdf-1 pretreatment. w ... | 1997 | 9108384 |
| evidence of hiv-2 infection in equatorial guinea (central africa): partial genetic analysis of a b subtype virus. | a case of hiv-2 infection is described in a 35-year-old woman born in malabo, equatorial guinea, who migrated to madrid, spain, in 1995. it was determined through questioning the woman that her only hiv-associated risk factor was unprotected heterosexual contacts in her country of origin. her ex-husband, to whom she had been married for 18 years, was also from equatorial guinea and was known to have had multiple sex partners. the woman reported having had heterosexual encounters with five oth ... | 1997 | 9075486 |
| seroprevalence and coprevalence of hiv and hbsag in nigerian children with/without protein energy malnutrition. | in order to assess the seroprevalence and coprevalence of hepatitis-b surface antigen (hbsag), human immunodeficiency virus-1 and -2 (hiv-1 and -2) antibodies in nigerian children with/without protein energy malnutrition (pem), we studied plasma specimens of 206 children with pem and 200 apparently healthy reference children aged between 1 and 3 years by enzyme-linked immunosorbent assays (elisa). hiv-seropositive cases were confirmed by immunoblotting (ib). of the children studied, eight (4%) o ... | 1997 | 9107364 |
| [serotypes of the human immunodeficiency virus type 1 in madrid]. | hiv-1 shows high genetic variability, mainly in the genomic region codifying the envelope proteins, which are the most immunogenic. this fact explains the high heterogeneity of antibodies against hiv-1 epitopes. both genetic and serologic diversity has allowed to classify hiv-1 variants in several subtypes (genotypes and serotypes, respectively). the clinical and epidemiological significance of infection caused by each subtype remains to be clarified. | 1997 | 9102487 |
| measurement of levels of human immunodeficiency virus type 1 reverse transcriptase (rt) and rt activity-blocking antibody in human serum by a new standardized colorimetric assay. | standardization and calibration of a new colorimetric assay for detection of reverse transcriptase (rt) was carried out for optimal detection of rt activity-blocking antibody (rtb-ab) in serum. a total of 99 of 100 swedish and 54 of 54 african human immunodeficiency virus type 1 (hiv-1) antibody-positive individuals had rtb-ab. the one rtb-ab-negative hiv-1 serum sample from a swedish individual was obtained early during seroconversion. five of 615 hiv-1-negative sera from tumor patients, pregna ... | 1997 | 9114385 |
| cd8+ cytotoxic t lymphocytes of a cynomolgus macaque infected with simian immunodeficiency virus (siv) mac32h-j5 recognize a nine amino acid epitope in siv gag p26. | a detailed analysis of simian immunodeficiency virus (siv)-specific cytotoxic t lymphocyte (ctl) responses and the identification of the proteins and epitopes they target may improve the design of immunotherapeutic interventions and provide insights into aids pathogenesis. here, we identified a new ctl epitope in the siv gag protein, recognized by cd8+ and mhc class i-restricted ctl clones from a long-term asymptomatic cynomolgus macaque (macaca fascicularis) infected with sivmac32h-j5. using ov ... | 1997 | 9129654 |
| development of a multiplex pcr assay for the simultaneous detection and discrimination of hiv-1, hiv-2, htlv-i and htlv-ii. | multiplex polymerase chain reaction (pcr) has been established as a general technique for the simultaneous amplification of different target sequences. uses of multiplex include pathogens identification, linkage analysis and genetic disease diagnosis. the high sensitivity of pcr may produce false-positive results due to contamination with previously amplified material. | 1996 | 9137864 |
| the 80's loop (residues 78 to 85) is important for the differential activity of retroviral proteases. | the abundance of structural data available for retroviral proteases affords a unique opportunity to investigate structure activity relationships. our approach attempts to genetically engineer an hiv (human immunodeficiency virus)-1 protease that is functionally equivalent to the hiv-2 and the siv (simian immunodeficiency virus) enzymes and conversely to engineer an hiv-2 protease that is functionally equivalent to the hiv-1 enzyme. for this purpose, the hiv-2 and siv proteases were cloned and ch ... | 1997 | 9126830 |
| potency comparison of peptidomimetic inhibitors against hiv-1 and hiv-2 proteinases: design of equipotent lead compounds. | hiv-1 and hiv-2 proteinases (pr) are responsible for the processing of viral polyproteins, a step that is crucial for the formation of infectious virus particles. pr represents one of the most important targets for antiviral chemotherapy. inhibitors of hiv-1 pr usually exhibit a 10- to 100-fold weaker affinity for hiv-2 pr. in order to design subnanomolar inhibitors for both hiv-1 and hiv-2 prs, we prepared a series of compounds varying in the type of scissile bond replacement as well as in the ... | 1997 | 9143353 |
| solution structure of the hiv-2 tar-argininamide complex. | the trans-activating region (tar) rna-tat protein interaction is important for activation of transciption in the human immunodeficiency virus (hiv). a model complex for this interaction composed of the two base bulge hiv-2 tar and the amide derivative of arginine was studied by multidimensional heteronuclear nmr. because of the improved spectral properties of the hiv-2 tar complex, a larger number of noes in the bulge region were observed than in earlier studies of the hiv-1 tar-argininamide com ... | 1997 | 9126842 |