Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| early detection of antibodies to human immunodeficiency virus 1 by a third-generation enzyme immunoassay. a comparative study with the results of second-generation immunoassays and western blot. | the aim of the study was to examine the sensitivity and the specificity of a hiv-1/hiv-2 third-generation enzyme immunoassay, the abbott recombinant hiv-1/hiv-2 third-generation enzyme immunoassay, which is reported to detect simultaneously igg and igm. sensitivity was evaluated with sera from seropositive subjects and a series of samples from eight hiv-1 seroconverting subjects. results were compared with western blot, second-generation immunoassays (including vidas hiv-1 + 2) and an hiv-1 anti ... | 1994 | 7856933 |
| the molecular epidemiology of hiv in asia. | the human immunodeficiency virus (hiv) was introduced readily into asia and has quickly spread between asian states through both parenteral and sexual modes of transmission. only 1 year after thailand's epidemic wave among intravenous drug users (idus) in 1988, the virus spread to the adjacent myanmar and malaysia, and another year later idus were infected in parts of india and china bordering myanmar. several methods can be used to quantify the genetic diversity, divergence, or variation within ... | 1994 | 7857556 |
| human immunodeficiency virus type 1 and type 2 seroprevalence in cornea donors. | routine screening of cornea donors for human immunodeficiency virus type 1 (hiv-1) has been established and has reduced the risk of hiv-1 transmission to a minimum. screening for hiv-2 is less common. we evaluated 100 cornea donors for hiv-2 and 166 cornea donors for hiv-1 according to our routine screening procedure. enzyme-linked immunosorbent assays (elisas) with high sensitivity were used to detect antibodies in donor blood. hiv-2 seroconversion was not found in any of the 100 cases tested, ... | 1994 | 7864930 |
| immunization with virion-derived glycoprotein 130 from hiv-2 or siv protects macaques against challenge virus grown in human or simian cells or prepared ex vivo. | we have compared in the macaque model the efficacy of the virion-derived glycoprotein of hiv-2ben (hiv-2 gp130) with that of sivmac251/32h (siv gp130). the latter vaccination trial was in part combined with vaccinia virus (vv) priming. both antigen preparations induced a strong humoral, but a weak cellular, immune response. the first challenge was performed with autologous virus grown on a human t cell line. more than 50% of the monkeys immunized with hiv-2 gp130 (five of nine) and 63% of the mo ... | 1994 | 7865316 |
| comparative functional analysis of the various lentivirus long terminal repeats in human colon carcinoma cell line (sw480 cells) and feline renal cell line (crfk cells). | basal promoter activities of various lentiviral long terminal repeats (ltrs) in a human colon carcinoma cell line (sw480 cells) and a feline renal cell line (crfk cells) were examined by the chloramphenicol acetyltransferase (cat) assay using the ltr-cat reporter plasmids. in sw480 cells, the basal promoter activities induced by ltrs of visna virus, caprine arthritis-encephalitis virus (caev), and simian immunodeficiency virus (sivagm) were moderate, and those induced by ltrs of human immunodefi ... | 1994 | 7865591 |
| hiv antibodies among intravenous drug users in bahrain. | a 12-month study was conducted to identify risk factors for human immunodeficiency virus (hiv) infections among intravenous drug users (idu) attending drug rehabilitation clinic of the psychiatric hospital, manama, bahrain. patients provided demographic and behavioural information based on a questionnaire. two hundred and forty male idus participated in the study on voluntary basis. the seroprevalence of hiv was 21.1 per cent. the presence of hiv antibody was associated with educational status, ... | 1994 | 7868834 |
| prevalence of hiv infection and high-risk characteristics among leprosy patients of south india; a case-control study. | with the observation of the occurrence of the human immunodeficiency virus (hiv) infection among leprosy patients in our pilot study carried out in tamil nadu, south india, a case-control study was planned to explore whether hiv infection is a risk factor for leprosy and to understand the characteristics of hiv infection and high-risk behaviors among leprosy patients. we screened 556 patients and 1004 nonleprosy controls (matching 502 cases for age, sex and area of residence) for hiv-1 and hiv-2 ... | 1994 | 7868949 |
| early helper t-cell dysfunction in simian immunodeficiency virus but not in human immunodeficiency virus type-2-infected macaques. | both naive and vaccinated macaques acquired a virus-specific proliferative helper t-cell reactivity in response to infection with the nonpathogenic human immunodeficiency virus type 2 (hiv-2). in contrast, macaques infected with the pathogenic simian immunodeficiency virus of the macaque strain (sivmac) did not develop a helper t-cell response. furthermore, a vaccine-induced preexisting t-cell reactivity was abrogated after sivmac infection in vaccine failures. these differences may reflect the ... | 1994 | 7869358 |
| [problems in the diagnosis of aids]. | diagnosis of human immunodeficiency virus (hiv) infection depends mainly on the detection of hiv-specific antibodies in the serum. if a seropositive patient has symptoms and signs of aids indicator diseases he (or she) will be diagnosed as having aids. if a patient is seronegative to hiv, some other diseases should be evaluated to explain the symptom related to the immunodeficiency. however, diagnosis of aids may be possible when a patient has aids indicator diseases and decreased cd4 positive c ... | 1994 | 7869588 |
| cardiac morbidity in the human immunodeficiency virus infection. | to evaluate the cardiac involvement in human immunodeficiency virus (hiv) infection. | 1994 | 7873220 |
| ultrasensitive retrovirus detection by a reverse transcriptase assay based on product enhancement. | reverse transcriptase (rt) is an indispensable component of infectious retroviruses. we have developed an ultrasensitive rt test in which rna of bacteriophage ms2 serves as the template for rt-mediated cdna synthesis. a fragment of the cdna is selectively amplified by polymerase chain reaction and the amplification product is analyzed by southern blot hybridization or enzyme immunoassay. the procedure was 10(6) to 10(7) times more sensitive than a conventional rt test and detected as little as 1 ... | 1994 | 7509077 |
| sexually transmitted diseases in ibadan in the 1990's: hiv infection--an additional dimension. | five hundred and fifty-one patients attending the special treatment clinic (stc) of the university college hospital, ibadan, between january 1989 and july 1990 were investigated for the common sexually transmitted diseases to determine the current relative prevalence rates of these infections. the patients were also investigated for human immunodeficiency virus (hiv) infection. of the 551 patients, 384 (69.9%) were diagnosed as having sexually transmitted diseases. the most frequent stds were go ... | 1994 | 7653404 |
| igg2 associated hypergammaglobulinaemia in some nigerians with hiv infection. | concentrations of immunoglobulins (iga, igg and igm) were measured in nigerians with (hiv) infection. considerable elevations up to two-fold the reference values were observed for igg and igm in the patient group as a whole but elevations in iga concentration were least marked albeit significantly different from the healthy subjects. elevation of a particular isotype was not always concomitant with elevation of the other major classes in the same patient. overall, these elevations were observed ... | 1994 | 7653407 |
| survey of human immunodeficiency virus infection among pregnant women in england and wales: 1990-93. | we report on the first four years (1990-93) of a survey within the national hiv prevalence monitoring programme. the survey's objective is to monitor the prevalence of infection with the human immunodeficiency virus (hiv) in pregnant women in london and elsewhere in england. the survey--based in forty centres that offer antenatal care in london, greater manchester, west yorkshire, and adjacent non-metropolitan areas--uses repeated cross sectional serosurveillance for anti-hiv-1 and 2 and the unl ... | 1994 | 7527276 |
| differentiation between human immunodeficiency virus type 1 (hiv-1) and hiv-2 isolates by nonradioisotopic reverse transcriptase-typing assay. | we tested whether human immunodeficiency virus type 1 (hiv-1) could be differentiated from hiv-2 by a reverse transcriptase (rt)-typing assay that measured the reduction of enzyme activity owing to specific antibody. rt-inhibiting antibody was examined for hiv type specificity by a new nonradioisotopic rt assay. antibodies from four rabbits immunized with recombinant hiv-1 rt and from 23 hiv-1-seropositive individuals all specifically inhibited the enzyme activities of two hiv-1 strains (lav-1 a ... | 1994 | 7527425 |
| biological and biochemical anti-hiv activity of the benzothiadiazine class of nonnucleoside reverse transcriptase inhibitors. | a series of benzothiadiazine derivatives were screened against the human immunodeficiency virus (hiv) and certain structure-activity relationships were defined for anti-hiv activity in this chemical class. the selected representative nsc 287474 was a highly potent inhibitor of hiv-induced cell killing and hiv replication in a variety of human cell lines, as well as in fresh human peripheral blood lymphocytes and macrophages. the compound was active against a panel of biologically diverse laborat ... | 1994 | 7529014 |
| enzymatic properties of two mutants of reverse transcriptase of human immunodeficiency virus type 1 (tyrosine 181-->isoleucine and tyrosine 188-->leucine), resistant to nonnucleoside inhibitors. | a number of structurally diverse compounds have been shown to be potent inhibitors of the dna polymerase activity of human immunodeficiency virus (hiv-1) reverse transcriptase (rt). the compounds can be grouped into two broad classes: nucleoside analogs and nonnucleoside inhibitors. the nonnucleoside inhibitors are quite specific for the polymerase activity of hiv-1 rt; they do not affect the polymerase activity of hiv-2 rt or the ribonuclease h (rnase h) activity of either hiv-1 rt or hiv-2 rt. ... | 1994 | 7529032 |
| inhibition of human immunodeficiency virus type 1 reverse transcriptase by the 5'-triphosphate beta enantiomers of cytidine analogs. | (-)-beta-l-2',3'-dideoxycytidine (l-ddc) and (-)-beta-l-2',3'-dideoxy-5-fluorocytidine (l-fddc) have been reported to be potent and selective inhibitors of human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) in vitro. in the present study, the 5'-triphosphates of l-ddc (l-ddctp) and l-fddc (l-fddctp) were demonstrated to competitively inhibit hiv-1 reverse transcriptase (rt), with inhibition constants (kis) of 2 and 1.6 microm, respectively, when a poly(ri).oligo(dc)10-15 template pri ... | 1994 | 7530932 |
| the catalytic properties of the reverse transcriptase of the lentivirus equine infectious anemia virus. | the reverse transcriptase (rt) of equine infectious anemia virus (eiav) shares sequence similarity with the rts of other lentiviruses, particularly with the rts of human immunodeficiency viruses types 1 and 2 (hiv-1 and hiv-2, respectively), the causative agents of acquired immunodeficiency syndrome (aids). there is a 41-42% sequence identity between eiav rt and both hiv rts (which have 61% sequence identity to each other). we have compared the enzymic properties of eiav rt with those of hiv-1 r ... | 1994 | 7509281 |
| kinetic and mutational analysis of human immunodeficiency virus type 1 reverse transcriptase inhibition by inophyllums, a novel class of non-nucleoside inhibitors. | inophyllums are novel non-nucleoside inhibitors of human immunodeficiency virus (hiv) type 1 reverse transcriptase identified through an enzyme screening program and isolated from the plant calophyllum inophyllum. the kinetics of reverse transcriptase inhibition by inophyllum b were characterized using recombinant purified enzyme, a heteropolymeric rna template, and a scintillation proximity assay. preincubation of inhibitor with the enzyme-template-primer complex for 11 min was required for max ... | 1994 | 7509800 |
| 3,5,8-trihydroxy-4-quinolone, a novel natural inhibitor of the reverse transcriptases of human immunodeficiency viruses type 1 and type 2. | the natural product of the red sea sponge verongia sp., identified as 3,5,8-trihydroxy-4-quinolone, was found to be a potent inhibitor of the rna-directed dna synthesis of the reverse transcriptases (rts) of human immunodeficiency viruses type 1 and type 2 (hiv-1 and hiv-2, respectively). this inhibition was unaffected by the nature of the primer template used for dna synthesis. the dna-dependent dna polymerase activity was inhibited to a lesser extent, whereas the ribonuclease h (rnase h) funct ... | 1994 | 7510944 |
| an epitope in the v1 domain of the simian immunodeficiency virus (siv) gp120 protein is recognized by cd8+ cytotoxic t lymphocytes from an siv-infected rhesus macaque. | cytotoxic t-lymphocyte (ctl) responses against the external envelope glycoprotein (gp120) of the simian immunodeficiency virus (siv) were studied in a rhesus macaque infected with sivmac/239. cd8+ t cells enriched from concanavalin a-stimulated peripheral blood mononuclear cells lysed autologous target cells infected with recombinant vaccinia virus vectors expressing the sivmac/239 or sivsm/h4 envelope protein, which share approximately 80% identity in amino acid sequence. a cd8+ ctl line derive ... | 1994 | 7511178 |
| characterization of hiv-1 strains isolated from patients treated with tibo r82913. | the drug sensitivities of human immunodeficiency virus type 1 (hiv-1) isolates from a group of four untreated and seven tibo r82913-treated patients were determined in a reverse transcriptase (rt) assay. five of the treated patients harbored hiv-1 isolates with r82913 sensitivity comparable to that of the isolates of untreated patients, ranging from almost 2-fold higher sensitivity to 13-fold lower sensitivity than that of recombinant p66 rt. from one of the seven treated patients, an hiv-1 stra ... | 1994 | 7514016 |
| cell line-dependent release of hiv-like gag particles after infection of mammalian cells with recombinant vaccinia viruses. | we investigated the production of gag particles by vero, cv-1, or 1d cells infected with different vaccinia virus recombinants expressing hiv gag or gag-pol genes. immunoblots of (centrifuged) culture media from 1d cells infected with vmm5, a vaccinia virus recombinant expressing the hiv-2 gag-pol genes, revealed the presence of abundant particles that contained (mostly processed) gag antigens. in contrast, gag particles were found only in low amounts in the culture medium from vero cells infect ... | 1994 | 7520722 |
| inhibition of reverse transcriptase of human immunodeficiency virus type 1 and chimeric enzymes of human immunodeficiency viruses types 1 and 2 by two novel non-nucleoside inhibitors. | we have studied the effects of two non-nucleoside reverse transcriptase inhibitors (nnrti), nitrophenyl phenyl sulfone (npps) and a potent derivative of oxathiin carboxanilide (uc-38), on enzymatically active molecular chimeras composed of complementary segments of the reverse transcriptases (rts) of human immunodeficiency virus type 1 (hiv-1) and -2 (hiv-2). the substances inhibit only the dna polymerase activity of hiv-1 rt with no effect on hiv-2 rt. the results suggest that there is a protei ... | 1994 | 7520874 |
| dual tropism for macrophages and lymphocytes is a common feature of primary human immunodeficiency virus type 1 and 2 isolates. | we have investigated the ability of human immunodeficiency virus type 1 (hiv-1) and hiv-2 isolates to infect and replicate in primary human macrophages. monocytes from blood donors were allowed to differentiate into macrophages by culture in the presence of autologous lymphocytes and human serum for 5 days before infection. a panel of 70 hiv-1 and 12 hiv-2 isolates were recovered from seropositive individuals with different severities of hiv infection. a majority of isolates (55 hiv-1 and all hi ... | 1994 | 7521920 |
| new tetrahydroimidazo[4,5,1-jk][1,4]-benzodiazepin-2(1h)-one and -thione derivatives are potent inhibitors of human immunodeficiency virus type 1 replication and are synergistic with 2',3'-dideoxynucleoside analogs. | tetrahydro-imidazo[4,5,1-jk][1,4]-benzodiazepin-2(1h)-one and -thione (tibo) derivatives were shown to specifically block human immunodeficiency virus type 1 (hiv-1) replication through a unique interaction with the hiv-1 reverse transcriptase (rt). through further modification of the lead compounds and structure-activity relationship analysis several new tibo derivatives that show high potency, selectivity, and specificity against hiv-1 have been obtained. a new tibo derivative, r86183, inhibit ... | 1994 | 7535037 |
| detection of hiv-1, hbv and hcv antibodies in blood donors from surat, western india. | hiv continues to spread in india mainly through heterosexual intercourse, but also among homosexual men and through blood transfusion. the government of india has mandated since 1992 that donor blood from the larger cities be screened for hepatitis b (hbv) and hiv infections. it is expected that this policy will be extended to other cities. surat is a town 250 km north of bombay. approximately 50% of blood is obtained from professional donors to meet the requirement of blood for transfusion. ... | 1994 | 7535499 |
| update -- aids treatment and epidemiology. | this update on aids treatment and epidemiology reviews the status of zidovudine (azt) treatment effectiveness, tuberculosis and hiv, vaccine development, vertical hiv transmission, and sexually transmitted diseases (std) and hiv transmission. the european multicenter concorde trial of azt involving 1749 people followed over a three-year period found no difference in time progression of aids or survival in the azt-treated versus placebo group. on tuberculosis (tb), hiv-induced immunosuppression ... | 1994 | 12287809 |
| aids in the gambia. | of concern in the gambia is a recent trend toward infection with the more aggressive, deadly human immunodeficiency virus type 1 (hiv-1). in 1990, hiv-2 infections among commercial sex workers outnumbered hiv-1 by a ratio of nine to one. according to the most recent data, however, hiv-1 was present in 42% of acquired immunodeficiency syndrome (aids) patients; 60% of aids cases were attributable to hiv-2 and 4% involved infection with both hiv-1 and hiv-2. about 2.2% of gambia's 1 million resi ... | 1994 | 12288999 |
| "immune" nairobi women also have "killer" t-cells. | further evidence that so-called "killer t-cells" could be the key to an hiv-vaccine has come from "immune" sex-workers in nairobi, kenya. earlier this year, british researcher sarah rowland-jones discovered a group of sex-workers in gambia, west africa, who seemed to be immune to hiv-infection. study of six of the women's blood revealed that five had the t-cells, which seek out and destroy infected cells. t-cells are produced as part of the immune-system's response to infection. a second group o ... | 1995 | 12289854 |
| "killer t-cells" give gambian sex-workers the cutting-edge on hiv. | the results of a gambian study may explain how 30 women out of 424 prostitutes in nairobi, kenya, remain uninfected with human immunodeficiency virus (hiv) after 5-6 years of prostitution, in spite of a prevalence rate of 90% in city sex workers. the gambian study also found a group of uninfected sex workers who had been repeatedly exposed to the virus; researchers believe killer t-cells are responsible. sarah rowland-jones of the institute of molecular medicine at the university of oxford, at ... | 1995 | 12288603 |
| aids breakthrough in 1995. | during 1995, there were a few provocative findings about the way hiv reproduces and survives. in january, two groups reported that hiv reproduces and is cleared from the body at higher rates than previously suspected. the immune system is able to keep pace with the virus through the first years of the infection but is finally overpowered. this leads to questions about why the immune system seems to be unable to permanently control the virus, and some light was shed on this issue in june with ... | 1995 | 12291701 |
| prior hiv-2 infection reduces chance of acquiring hiv-1. senegal. | dr. phyllis kanki, a scientist at the harvard school of public health, states that her 9-year study of prostitutes in senegal showed that those women who were infected with hiv-2, a weaker strain of hiv, were approximately 70% less likely to acquire hiv-1. hiv-2 can cause acquired immunodeficiency syndrome (aids), but it is much less virulent and much less aggressive. persons who are infected with hiv-2 may take 25 years to develop aids, while those with hiv-1 die from the disease in half that ... | 1995 | 12346426 |
| no direct relationship between hiv1/2 infection and hhv-6 antibody response in a large-scale european and african trial. | tropism of both human herpesvirus-6 (hhv-6) and human immunodeficiency virus (hiv) for cd4+ lymphocytes, and several studies on hiv enhancer transactivation by hhv-6 have suggested that hhv-6 could be implicated as a cofactor in the progression of hiv infection to aids. | 1995 | 15566794 |
| evaluation of screening kits for the detection of anti-human immunodeficiency virus type 1 and 2 (hiv-1/2) antibodies. | hiv-1/hiv-2 3rd generation (abbott), wellcozyme hiv 1 + 2 (murex), enzygnost anti-hiv 1/-hiv 2 (behring), and genelavia mixt (sanofi diagnostics pasteur) are currently registered by authorities as enzyme immunoassays (eias) for detecting hiv-1/2 infection. the present study dissects these reagents by means of the major antigenic components, assay principles and their actual performance. the performances have been evaluated by their test results in international panels of seroconversion, mixed ti ... | 1995 | 9774997 |
| hiv-1 and hiv-2 infections among u.s. peace corps volunteers returning from west africa. | background: the risk of acquiring hiv-1 and hiv-2 infections among expatriates in, and travelers to, west africa is not known. the objective of the study was to examine the risk of human immunodeficiency virus type 1 and type 2 (hiv-1 and hiv-2) infections among peace corps volunteers in west africa. methods: a cross-sectional serosurvey was carried out in 18 west african countries. subjects were 2491 returning peace corps volunteers. the main outcome measure was seropositivity for hiv-1 and hiv ... | 1995 | 9815380 |
| laboratory tests for human immunodeficiency viruses. | two types of human immunodeficiency viruses are known. both type 1 (hiv-1) and type 2 (hiv-2) can lead to aids. this article describes laboratory tests that are used for diagnosis of hiv infection and for monitoring disease progression or the effects of therapy. these tests are based on detection of host antibodies, viral antigens, viral nucleotide sequences, or cultivation of the virus in vitro. the principles underlying test methods for differentiation between hiv-1 and hiv-2 are described. | 1995 | 10155721 |
| update: hiv-2 infection among blood and plasma donors--united states, june 1992-june 1995. | human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) both cause acquired immunodeficiency syndrome (aids). following the licensure of combination hiv-1/hiv-2 screening enzyme immunoassays (eia), the food and drug administration (fda) recommended that beginning in june 1992 all donated whole blood, blood components, and source plasma be screened for antibody to hiv-2 because not all persons infected with hiv-2 can be detected by hiv-1 testing. this report describes the first two cases o ... | 1995 | 11361466 |
| virus reaches u.s. | the centers for disease control and prevention (cdc) announced that hiv-2 infection, previously isolated to western africa, has been found in the u.s. of the 62 people diagnosed with hiv-2 in the u.s., more than two-thirds are native africans. those born in the u.s. reported traveling to or having a sex partner from africa. since 1992, hiv-2 has been detected in blood and plasma donations twice. | 1995 | 11362808 |
| production of a highly cytopathic hiv-1 isolate from a human mucosal epithelial cell line cultured on microcarrier beads in serum-free medium. | the human colonic epithelial cell line ht-29 can be productively infected with various hiv-1 and hiv-2 isolates that are highly cytopathic for t lymphocytes. in each case, a chronically infected ht-29 cell line can be established, and progeny viruses retain their original properties including high cytopathogenicity for t cells. inasmuch as aids vaccines should include viral isolates capable of infecting mucosal epithelial cells, it may be useful to produce these isolates in such cells at a large ... | 1995 | 7535637 |
| thymic immunopathology and progression of sivsm infection in cynomolgus monkeys. | thymuses from 22 cynomolgus monkeys infected with simian immunodeficiency virus (sivsm) developed characteristic cortical and medullary changes including formation of b-cell follicles (8/21) and accumulation of virus immune complexes. advanced thymic histopathology was correlated with more pronounced immunodeficiency. sivsm provirus was detected by polymerase chain reaction (pcr) in most (16/18) thymuses and spliced viral env mrna in 3 (3/7) thymuses with advanced histopathologic changes indicat ... | 1995 | 7536107 |
| michellamine b, a novel plant alkaloid, inhibits human immunodeficiency virus-induced cell killing by at least two distinct mechanisms. | studies of the mechanism of action of michellamine b, a novel anti-human immunodeficiency virus (hiv) alkaloid from the tropical plant ancistrocladus korupensis, have revealed that the compound acts at two distinct stages of the hiv life cycle. the compound had no direct effect on hiv virions and did not block the initial binding of hiv to target cells. postinfection time course studies revealed that the agent partially inhibited hiv-induced cell killing and syncytium formation when added up to ... | 1995 | 7537029 |
| neutralizing monoclonal antibodies against human immunodeficiency virus type 2 gp120. | monoclonal antibodies (mabs) were obtained by immunizing mice with synthetic peptides corresponding to the third variable (v3) or the third conserved (c3) domain of the external envelope protein (gp120) of human immunodeficiency virus type 2 (hiv-2rod). one mab, designated b2c, which was raised against v3 peptide nki26, bound to the surface of hiv-2-infected cells but not to their uninfected counterparts. b2c was capable of neutralizing cell-free and cell-associated virus infection in an isolate ... | 1995 | 7538171 |
| the differential processing of homodimers of reverse transcriptases from human immunodeficiency viruses type 1 and 2 is a consequence of the distinct specificities of the viral proteases. | active, recombinant p68 reverse transcriptase (rt) from human immunodeficiency virus type 2 (hiv-2), with an nh2-terminal extension containing a hexahistidine sequence was isolated from extracts of escherichia coli by immobilized metal affinity chromatography. treatment of the purified p68/p68 homodimer of hiv-2 rt with recombinant hiv-2 protease generates stable, active heterodimer (p68/p58) that is resistant to further hydrolysis. analysis of this p68/p58 hiv-2 rt heterodimer revealed that whi ... | 1995 | 7539431 |
| natural protection against hiv-1 infection provided by hiv-2. | significant differences have been observed in the rates of transmission and disease development in human immunodeficiency virus (hiv) types 1 and 2. because many hiv-2-infected people remain asymptomatic for prolonged periods, the hypothesis that hiv-2 might protect against subsequent infection by hiv-1 was considered. during a 9-year period in dakar, senegal, the seroincidence of both hiv types was measured in a cohort of commercial sex workers. despite a higher incidence of other sexually tran ... | 1995 | 7539936 |
| intercellular adhesion molecule 3, a candidate human immunodeficiency virus type 1 co-receptor on lymphoid and monocytoid cells. | the cd4 molecule serves as the principal cell surface receptor common to both the human and simian immunodeficiency viruses (hiv-1, hiv-2 and siv). since binding to cd4 is not sufficient to permit virus entry, hiv 'co-receptors' have been implicated in mediating the fusion of viral and cellular membranes necessary for completing the entry process. in order to identify candidate co-receptor molecules, a panel of monoclonal antibodies (mabs) directed against adhesion molecules was tested for the a ... | 1995 | 7540195 |
| protection of a t-cell line from human immunodeficiency virus replication by the stable expression of a short antisense rna sequence carried by a shuttle rna molecule. | adenovirus va1 gene is efficiently transcribed by rna polymerase iii and gives rise to a small highly ordered rna. to inhibit replication of human immunodeficiency virus (hiv), a chimeric va1 rna molecule was designed that contained a short antisense rna sequence complementary to a conserved region of the hiv-1 rev encoding mrna (28 nucleotides). this sequence, which was inserted into a projecting loop of the va1 rna central domain, was mainly single stranded and available for binding with its c ... | 1995 | 7541291 |
| simultaneous mutations at tyr-181 and tyr-188 in hiv-1 reverse transcriptase prevents inhibition of rna-dependent dna polymerase activity by the bisheteroarylpiperazine (bhap) u-90152s. | the replacement of either tyr-181 or tyr-188 of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt) by the corresponding hiv-2 rt amino acids ile-181 or leu-188 is known to result in active mutant enzymes (y181i; y188l) with virtual loss of sensitivity towards three structural classes of nonnucleoside rt inhibitors; l-697,661, nevirapine, and tibo r82913. the bisheteroarylpiperazine (bhap) u-90152s, a highly specific inhibitor (ic50, 0.29 +/- 0.01 microm) of hiv-1 rt, inhibite ... | 1995 | 7544302 |
| localization of human immunodeficiency virus rev in transfected and virus-infected cells. | the rev gene product of human immunodeficiency virus (hiv) is obligatory for viral replication. rev interacts specifically with a structured rna sequence within the viral genome termed the rev response element (rre). although the importance of rev for the expression of viral proteins is well documented, its functional mechanism remains unresolved. previous studies identified rev in the absence of rre to be a nuclear protein localized primarily within the nucleoli. to extend our understanding of ... | 1995 | 7546906 |
| nucleotide sequence of the hiv-2 eho genome, a divergent hiv-2 isolate. | the hiv-2 eho isolate from cote d'ivoire has been characterized as a highly cytopathic hiv-2 strain, which can be differentiated from other isolates by the smaller size of its external envelope glycoprotein. the entire nucleotide sequence (10,352 bp) of the hiv-2 eho genome is filed in the embl/genbank data libraries under accession no. u27200. despite its high degree of variability, the genetic organization of hiv-2 eho was found to be similar to other hiv-2 and simian immunodeficiency virus ... | 1995 | 7546916 |
| nanoparticles as adjuvants for vaccines. | pmma nanoparticle adjuvants can be manufactured in a physicochemically reproducible manner. their particle size can be controlled within narrow limits. immunogens may be either incorporated or adsorbed to these nanoparticles. pmma nanoparticles induced significantly higher and more prolonged antibody responses against a variety of immunogens, including influenza virions and subunit vaccines, bsa, and hiv-1 and hiv-2 split vaccines. in addition, a protective immune response against challenge with ... | 1995 | 7551231 |
| the epidemic of hiv/aids in abidjan, côte d'ivoire: a review of data collected by projet retro-ci from 1987 to 1993. | we present a review of epidemiologic data collected by projet retro-ci between 1987 and 1993 on trends in human immunodeficiency virus type 1 (hiv-1) and hiv-2 infections and on cases of aids in abidjan, côte d'ivoire. overall rates of hiv infection in pregnant women had already reached 10% in 1987, and have increased only modestly since then. in contrast, in 1992-1993, rates in men with sexually transmitted diseases and in female commercial sex workers reached 27 and 86%, respectively. the incr ... | 1995 | 7552498 |
| analysis of cross reactivity of retrovirus proteases using a vaccinia virus-t7 rna polymerase-based expression system. | we have used the vaccinia virus-t7 rna polymerase-based expression system for studies on the activity of proteases from various retroviruses on homologous and heterologous gag polyproteins in eukaryotic cells. proteases from human immunodeficiency virus (hiv) types 1 and 2, equine infectious anaemia virus, human t cell leukaemia virus type 1 and human spumavirus were produced and were shown to cleave their cognate gag substrates produced in trans. analysis of cross reactivity revealed that lenti ... | 1995 | 7561754 |
| high prevalence of hepatitis b, c, and e markers in young sexually active adults from the central african republic. | the central african republic is located in tropical africa, where both the human immunodeficiency virus (hiv) and hepatitis b virus (hbv) are highly endemic. the exact prevalence of hepatitis c virus (hcv) and hepatitis e virus (hev) markers in this country is unknown. the aim of the study was to determine, according to hiv and hbv serostatus, the prevalence of these markers in young sexually active adults in the central african republic. one hundred and fifty-seven consecutive patients attendin ... | 1995 | 7561802 |
| quantitative structural activity relationship study of bis-tetraazacyclic compounds. a novel series of hiv-1 and hiv-2 inhibitors. | this work describes a study of quantitative structural activity relationships (qsar) of bis-tetraazamacrocyclic compounds. these compounds represent a novel class of very potent and selective anti-hiv inhibitors, with a new mode of action. the qsar study correlates structural features of the compounds with anti-hiv activity, resulting in a model which has a high predictive capacity (predictive r2 = 0.79). this predictive model will be of major importance for the design of new anti-hiv inhibitors ... | 1995 | 7562918 |
| infection with hepatitis viruses (b and c) and human retroviruses (htlv-1 and hiv) in saudi children receiving cycled cancer chemotherapy. | serological markers of hepatitis b virus (hbv), hepatitis c virus (hcv), human t-cell lymphotropic virus type 1 (htlv-1), and human immunodeficiency viruses (hiv-1 and hiv-2) were studied in 53 saudi children (31 males, 22 females; 1-12 years of age) receiving cycled cancer chemotherapy and in 168 healthy saudi children taken as control. exposure to hbv in the patients was similar to that in the control (6 per cent hbsag in patients v. 7 per cent in the control; 19 per cent exposure rate in pati ... | 1995 | 7563271 |
| the pett series, a new class of potent nonnucleoside inhibitors of human immunodeficiency virus type 1 reverse transcriptase. | to identify the minimal structural elements necessary for biological activity, the rigid tricyclic nucleus of the known human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt) inhibitor tetrahydroimidazobenzodiazepinthione was subjected to systematic bond disconnection to obtain simpler structures. a rational selection and testing of modeled analogs containing these potential pharmacophoric moieties led to the discovery of a new series of nonnucleoside inhibitors of rt. the lead c ... | 1995 | 7574525 |
| intrapatient variability of the human immunodeficiency virus type 2 envelope v3 loop. | studies of hiv-2 infection have shown lower rates of sexual and perinatal transmission and a prolonged incubation period to aids as compared to hiv-1. to evaluate the role of genetic variation in hiv pathogenesis, we studied intrapatient variability in the v3 loop of the hiv-2 envelope gene over time in five seropositive individuals. proviral sequences derived from uncultured pbmc dna (n = 102) demonstrated an average sequence heterogeneity within a sample of 1.4% (0-4.1%). this was significantl ... | 1995 | 7576918 |
| resistance of hiv type 1 to proteinase inhibitor ro 31-8959. | during replication of human immunodeficiency virus type 1 (hiv-1), proteolytic cleavage of gag and gag-pol precursor proteins into different functional protein subunits is catalyzed by the viral proteinase, and this enzyme is the target of the antiviral proteinase inhibitor, ro 31-8959. we investigated in vitro which hiv mutants with reduced sensitivity to ro 31-8959 emerged during proteinase inhibition treatment; from three different hiv-1 strains, comparable progeny virus resistant to proteina ... | 1995 | 7576926 |
| hiv-specific cytotoxic t-cells in hiv-exposed but uninfected gambian women. | a crucial requirement in the rational design of a prophylactic vaccine against the human immunodeficiency virus (hiv) is to establish whether or not protective immunity can occur following natural infection. the immune response to hiv infection is characterized by very vigorous hiv-specific cytotoxic t-lymphocyte (ctl) activity. we have identified four hiv-1 and hiv-2 cross-reactive peptide epitopes, presented to ctl from hiv-infected gambians by hla-b35 (the most common gambian class i hla mole ... | 1995 | 7584954 |
| hiv-1 recombinant poxvirus vaccine induces cross-protection against hiv-2 challenge in rhesus macaques. | rhesus macaques were immunized with attenuated vaccinia or canarypox human immunodeficiency virus type 1 (hiv-1) recombinants and boosted with hiv-1 protein subunits formulated in alum. following challenge with hiv-2sbl6669, three out of eight immunized macaques resisted infection for six months and another exhibited significantly delayed infection, whereas all three naive controls became infected. immunizations elicited both humoral and cellular immune responses; however, no clear correlates of ... | 1995 | 7585061 |
| long-term protection against siv-induced disease in macaques vaccinated with a live attenuated hiv-2 vaccine. | the aim of this study was to test the ability of a live attenuated human immunodeficiency virus type 2 (hiv-2) vaccine to protect cynomolgus monkeys against superinfection with a pathogenic simian immunodeficiency virus (sivsm). this report is an update on our previously reported observation period of nine months. the new data here show that three of four monkeys vaccinated with live hiv-2 were protected against immunosuppression and siv-induced disease during more than five years of follow-up. ... | 1995 | 7585217 |
| sporadic als/mnd: a global neurodegeneration with retroviral involvement? | sporadic amyotrophic lateral sclerosis may be an aetiologically heterogenous disease. we confirmed elevated circulating igg immune complexes, and altered igg seroreactivities against human retroviral antigens (hiv-2 and htlv immunoblots) in overlapping subgroups of patients. together with preliminary findings of a positive polymerase chain reactivity for human t-lymphotropic virus (htlv.tax/rex) in blood leukocytes of 5 out of 14 sals patients, we interpret this as evidence for a retroviral invo ... | 1995 | 7595609 |
| hiv-1, hiv-2, htlv-i/ii and treponema pallidum infections: incidence, prevalence, and hiv-2-associated mortality in an occupational cohort in guinea-bissau. | the prevalence and incidence of human immunodeficiency virus types 1 and 2 (hiv-1, hiv-2), human t-lymphotropic virus types i and ii (htlv-i/ii), and syphilitic infections and the association between these infections were determined in a cohort of police officers in guinea-bissau. between january 1990 and december 1992, 1,384 subjects (1,241 men and 143 women) were included in the study; and of the first 879 tested, 561 were tested at least for a second time. the overall seroprevalence of hiv-1 ... | 1995 | 7600111 |
| a newly developed immunofluorescence assay for simultaneous detection of antibodies to human immunodeficiency virus type 1 and type 2. | immunofluorescence assays (ifa) that simultaneously distinguish between antibodies against closely related human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) infections have not been readily available. serum specimens from 95 hiv-1-infected, 26 hiv-2-infected and 3 hiv-1/hiv-2 dually infected individuals and 106 seronegative blood donors were evaluated for the ability to serologically discriminate hiv-1 and hiv-2 infections by means of ifa employing three types of cells whose morphol ... | 1995 | 7601900 |
| polyanion inhibitors of human immunodeficiency virus and other viruses. 1. polymerized anionic surfactants. | a series of polyanionic compounds was synthesized and evaluated for their activity against human immunodeficiency virus (hiv-1, hiv-2) and various other rna and dna viruses. several compounds, i.e., 2p, 3p, 8p, 13p, 14p, 15p, 17p, 18p, and 19p, proved active against hiv-1 within the concentration range of 0.1-3 micrograms/ml while not being toxic to the host cells (cem, mt-4) at concentrations up to 100 micrograms/ml or higher. as a rule, these polyanionic compounds proved also active, albeit at ... | 1995 | 7608908 |
| the peri-kappa b site mediates human immunodeficiency virus type 2 enhancer activation in monocytes but not in t cells. | human immunodeficiency virus type 2 (hiv-2), like hiv-1, causes aids and is associated with aids cases primarily in west africa. hiv-1 and hiv-2 display significant differences in nucleic acid sequence and in the natural history of clinical disease. consistent with these differences, we have previously demonstrated that the enhancer/promoter region of hiv-2 functions quite differently from that of hiv-1. whereas activation of the hiv-1 enhancer following t-cell stimulation is mediated largely th ... | 1995 | 7609053 |
| identification and mapping of inhibitory sequences in the human immunodeficiency virus type 2 vif gene. | human immunodeficiency virus (hiv) regulates the expression of its genes temporally at the mrna processing step. a subset of the mrna species which encode the structural and some accessory genes contains inhibitory sequences (ins or crs elements) which prevent nuclear export of the rna or its utilization in the cytoplasm. such inhibition is overridden by the interaction of a viral protein, rev, with its rna target sequence, rre. the vif gene product, which is essential for virus replication in v ... | 1995 | 7609089 |
| comparative analysis of the x-ray structures of hiv-1 and hiv-2 proteases in complex with cgp 53820, a novel pseudosymmetric inhibitor. | the human immunodeficiency virus (hiv) is the causative agent of acquired immunodeficiency syndrome (aids). two subtypes of the virus, hiv-1 and hiv-2, have been characterized. the protease enzymes from these two subtypes, which are aspartic acid proteases and have been found to be essential for maturation of the infectious particle, share about 50% sequence identity. differences in substrate and inhibitor binding between these enzymes have been previously reported. | 1995 | 7613867 |
| role of the conserved dipeptide gly75 and cys76 on hiv-1 vpr function. | vpr is one of the accessory proteins encoded by the hiv-1 genome. several interesting features associated with vpr include incorporation into virus particles, ability to oligomerize, localization in the nucleus, and positive effect on virus production and replication. in order to understand the structure-function relationship of vpr, we have analyzed the role of the gly75 and cys76 (gc) residues which are highly conserved in hiv-1 vpr and in vpr and vpx of hiv-2/siv. we have generated several su ... | 1995 | 7618286 |
| mutational analysis of the conserved cysteine residues in the simian immunodeficiency virus matrix protein. | the matrix protein (ma) of human and simian immunodeficiency viruses (hiv and siv) is encoded by the amino-terminal region of the gag precursor and has been suggested to be involved in different processes during the early and late stages of the virus life cycle. the ma protein of siv contains three cysteine residues at positions 57, 83, and 87, which are also highly conserved among hiv-2 isolates. in order to study the functional significance of these residues in virus morphogenesis, a series of ... | 1995 | 7618287 |
| update: hiv-2 infection among blood and plasma donors--united states, june 1992-june 1995. | human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) both cause acquired immunodeficiency syndrome (aids). following the licensure of combination hiv-1/hiv-2 screening enzyme immunoassays (eia), the food and drug administration (fda) recommended that beginning in june 1992 all donated whole blood, blood components, and source plasma be screened for antibody to hiv-2 because not all persons infected with hiv-2 can be detected by hiv-1 testing (1,2). this report describes the first two c ... | 1995 | 7630339 |
| neutralizing monoclonal antibody against a external envelope glycoprotein (gp110) of sivmac251. | three monoclonal antibodies (m318t, m56s and m815) against an external envelope glycoprotein (gp110) of simian immunodeficiency virus (siv) mac251 were obtained by immunizing balb/c mice with recombinant gp110 (rgp110). all three monoclonal antibodies reacted with the surface of cells infected with sivmac251 but not with that of uninfected counterparts. the binding activity of these monoclonal antibodies against native gp110 was confirmed by means of western blotting. one of them, m318t neutrali ... | 1995 | 7632464 |
| unusual single-stranded polyribonucleotides as potent anti-hiv agents. | polyribonucleotides (ptmg and pmti) containing 1-methyl-6-thioguanosine or 1-methyl-6-thioinosine, respectively, as the sole nucleoside component are shown to be potent inhibitors of various strains of hiv-1 and hiv-2 in a number of human lymphocyte and macrophage cell lines in tissue culture as well as in fresh human peripheral blood lymphocytes and macrophages. pmti and pmtg exhibit potencies in the range of 10(-7)-10(-8) m in these systems. the polynucleotides are active against virus strains ... | 1995 | 7650678 |
| resistance to nucleoside analogs of selective mutants of human immunodeficiency virus type 2 reverse transcriptase. | we have studied selected mutants of human immunodeficiency virus type 2 (hiv-2) reverse transcriptase (rt) in a cell-free system in order to assess whether the mutant proteins exhibit a reduction in the sensitivity to nucleoside analog inhibitors similar to that of hiv-1 rt. we have modified, by site-directed mutagenesis, several of those amino acid residues so that their equivalent substitutions in hiv-1 rt have led to the formation of hiv-1 rt variants with the highest degree of resistance to ... | 1995 | 7527086 |
| human immunodeficiency virus type 2 (hiv-2) env gene analysis: prediction of glycoprotein epitopes important for heterotypic neutralization and evidence for three genotype clusters within the hiv-2a subtype. | the env gene sequences of ten tissue-culture-adapted human immunodeficiency virus type 2 (hiv-2) isolates from west african patients were determined. alignment and comparison of the gene sequences and putative translation products with database sequences revealed 11-29% diversity at the nucleotide level and 15-31% variation at the protein level. from analysis of glycoproteins of hiv-2 strains sensitive and resistant to neutralization by hiv-1 antisera, five regions were identified as putative ta ... | 1995 | 7531216 |
| dimerization kinetics of hiv-1 and hiv-2 reverse transcriptase: a two step process. | the dimerization processes of the human immunodeficiency virus (hiv) types 1 and 2 reverse transcriptase (rts) from their subunits have been investigated using a number of complementary approaches (fluorescence spectroscopy, size exclusion-hplc and polymerase activity assay). the formation of the native heterodimeric form of hiv-1 and hiv-2 rt occurs in a two step process. the first step is a concentration-dependent association of the two subunits (p66 and p51) to give a heterodimeric intermedia ... | 1995 | 7531247 |
| neither whole inactivated virus immunogen nor passive immunoglobulin transfer protects against sivagm infection in the african green monkey natural host. | attempts to protect against infection with simian immunodeficiency virus (siv)mac grown in rhesus peripheral blood mononuclear cells (pbmcs) using whole inactivated virus immunogen or passive transfer of antibody have so far universally failed. however, such experiments have succeeded in the closely related human immunodeficiency virus (hiv)-2/cynomolgus system. to determine whether the failure in the sivmac system is typical of primate lentiviruses we performed vaccination and passive transfer ... | 1995 | 7532099 |
| peyssonols a and b, two novel inhibitors of the reverse transcriptases of human immunodeficiency virus types 1 and 2. | two new sesquiterpene hydroquinones, peyssonol a and peyssonol b, of the red sea algae peyssonelia sp., have been shown to be potent inhibitors of the rna-directed dna synthesis of the reverse transcriptases (rts) of human immunodeficiency virus (hiv)-1 and hiv-2. the dna-dependent dna polymerase activity is inhibited to a lesser extent, whereas the rnase h activity is unaffected. the inhibition of the dna polymerase activities is independent of the nature of the template primers used. peyssonol ... | 1995 | 7532386 |
| mechanism of resistance to u-90152s and sensitization to l-697,661 by a proline to leucine change at residue 236 of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase. | bisheteroarylpiperazines (bhaps) are highly specific inhibitors of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt). bhap-resistant hiv-1 is sensitized to other classes of nonnucleoside rt inhibitors and this has been primarily attributed to a proline-to-leucine substitution at amino acid 236 (p236l) of hiv-1 rt. to understand the basis for the in vitro sensitization-resistance phenomenon, single base pair mutations at amino acid p236 in hiv-1 rt were introduced to obtain p ... | 1995 | 7532595 |
| differentiation of human immunodeficiency virus type 1 (hiv-1) infections with hiv-2-cross-reacting antibody from mixed infections with hiv-1 and hiv-2 by serological absorption test. | the interpretation of dual seroreactivity with human immunodeficiency virus type 1 (hiv-1) and hiv-2 in blood samples is a serious problem facing aids researchers worldwide. some samples of sera from hiv-1-infected patients showed a serological cross-reaction with hiv-2, causing confusion regarding the serodiagnosis. therefore, we tried to differentiate these serum samples from those containing real mixed infections with both types of virus. sera from patients with hiv-1 infections with hiv-2 cr ... | 1995 | 7665636 |
| an infectious chimeric human immunodeficiency virus type 2 (hiv-2) expressing the hiv-1 principal neutralizing determinant. | the human immunodeficiency virus type 1 strain mn (hiv-1mn) principal neutralizing determinant (pnd, v3 loop) was introduced into infectious molecular clones hiv-2kr and simian immunodeficiency virus mm239 (sivmm239) by hybridization pcr, replacing the corresponding hiv-2 or siv envelope cysteine loops with the hiv-1 coding sequence. the hiv-2 chimera (hiv-2kr-mnv3) was found to be capable of infecting a number of t-cell lymphoblastic cell lines as well as primary peripheral blood mononuclear ce ... | 1995 | 7666543 |
| characteristics of a group of nonnucleoside reverse transcriptase inhibitors with structural diversity and potent anti-human immunodeficiency virus activity. | current thrust in controlling the acquired immune deficiency syndrome (aids) focuses on antiviral drug development targeting the infection and replication of the human immunodeficiency virus (hiv), the causative agent of aids. to date, treatment of aids has relied on nucleoside reverse transcriptase inhibitors such as azt, ddi, and ddc, which eventually become ineffective upon the emergence of resistant mutants bearing specific nucleotide substitutions. the anti-aids drug screening program of th ... | 1995 | 7475321 |
| [type 2 human immunodeficiency virus infection (hiv-2) in spain: analysis of the first 50 cases. spanish group for the study of hiv-2]. | infection by the human immunodeficiency virus type 2 (hiv-2) is endemic in west africa where it is responsible for many aids cases. hiv-2 has been described in subjects in other countries, mainly in african immigrants, although it may also be found in natives. the first cases of hiv-2 infection were identified in spain in 1988. | 1995 | 7475463 |
| both virus and host components are important for the manifestation of a nef- phenotype in hiv-1 and hiv-2. | while it has been demonstrated that the nef protein of simian immunodeficiency virus is obligatory for the establishment of high viral loads and the development of simian aids in rhesus macaques, demonstrating a critical role for the human immunodeficiency virus (hiv) nef protein in tissue culture has been elusive. data have been contradictory as to whether nef has a negative or positive influence on in vitro virus replication. in an attempt to define a role for nef during virus propagation in t ... | 1995 | 7483259 |
| performance evaluation of a particle agglutination test for antibody to human immunodeficiency virus 1: comparison with enzyme immunoassay. | a performance evaluation of a particle agglutination test (pat), manufactured by fujirebio inc., japan (serodia-hiv), for antibody to human immunodeficiency virus type-1 (anti-hiv-1) was carried out and compared with a currently available enzyme immunoassay (eia), manufactured by genetic systems corp., usa, (hiv-1/hiv-2 eia). testing 2,878 indian donor and patient samples, both tests showed 100% sensitivity and comparable specificity (pat: 99.8%; eia: 99.7% among donor samples). we conclude that ... | 1995 | 7483488 |
| hiv: the more things change, the more they stay the same. | the syndrome known as aids is eventually brought on after initial infection with hiv. infection with either hiv-1 or hiv-2 will lead to aids. however, different strains of hiv-1 have been found to exist, varying between continents. the strains, or clades, vary quite significantly in their surface antigens and genetic sequences. hiv-1 subtype b, the initial causative virus of aids in western industrialized countries, is reproducibly different from subtypes c and e, respectively found in sub-s ... | 1995 | 7489381 |
| tat functions to stimulate the elongation properties of transcription complexes paused by the duplicated tar rna element of human immunodeficiency virus 2. | in this study we have defined the in vitro requirements for transcriptional regulation of the hiv-2 ltr in response to the hiv-1 and hiv-2 tat proteins and addressed potential mechanisms of tat function. hiv-2 contains a duplicated tar rna stem-loop structure in contrast to the single stem-loop structure found in hiv-1 tar rna. we demonstrated that the hiv-2 proximal tar rna stem-loop structure was more important for in vitro transcriptional activation by the hiv-1 and hiv-2 tat proteins than th ... | 1995 | 7490754 |
| characterization of a cd4-expressing macaque cell line that can detect virus after a single replication cycle and can be infected by diverse simian immunodeficiency virus isolates. | primate lentiviruses such as human immunodeficiency virus (hiv) and simian immunodeficiency virus (siv) are phenotypically diverse, and virus isolates vary in cytopathicity, replication rate, and cell tropism. while all virus isolates infect primary peripheral blood lymphocytes, only a subset of strains infect established cd4-expressing t-cell lines. here, we describe the development and characterization of a macaque cell line that can be infected by all of the strains of siv that we have tested ... | 1995 | 7491763 |
| highly attenuated hiv type 2 recombinant poxviruses, but not hiv-2 recombinant salmonella vaccines, induce long-lasting protection in rhesus macaques. | immunization schemes employing priming with vector-based vaccine candidates followed by subunit booster administrations have been explored and shown to have merit in the human immunodeficiency virus type 1 (hiv-1) and simian immunodeficiency virus systems. in this study, we have assessed the priming capacity of highly attenuated poxvirus vector (nyvac and alvac)-based hiv-2 recombinants, as well as salmonella typhimurium hiv-2 recombinants in rhesus macaques. alvac- and nyvac-based vaccine candi ... | 1995 | 7492438 |
| mutational analysis of the substrate binding pocket of murine leukemia virus protease and comparison with human immunodeficiency virus proteases. | the differences in substrate specificity between moloney murine leukemia virus protease (mulv pr) and human immunodeficiency virus (hiv) pr were investigated by site-directed mutagenesis. various amino acids, which are predicted to form the substrate binding site of mulv pr, were replaced by the equivalent ones in hiv-1 and hiv-2 prs. the expressed mutants were assayed with the substrate val-ser-gln-asn-tyr decreases pro-ile-val-gln-nh2 (decreases indicates the cleavage site) and a series of ana ... | 1995 | 7493942 |
| detection of human immunodeficiency virus (hiv) type 1 antibodies by new automated microparticle enzyme immunoassay for hiv types 1 and 2. | we compared an automated microparticle double-antigen sandwich enzyme immunoassay (eia) for the imx test system recently developed by abbott with two established assays (the automated indirect vidas igg eia and the double-antigen sandwich eia from murex/wellcome) devised for the detection of human immunodeficiency virus type 1 (hiv-1) and hiv-2 antibodies. a total of 1,078 consecutive serum samples were tested prospectively with the three assays. in addition, we used retrospectively selected pan ... | 1995 | 7494024 |
| role of cd4 endocytosis in human immunodeficiency virus infection. | we have analyzed the role of cd4 endocytosis in human immunodeficiency virus (hiv) entry by measuring the infection of hela cells expressing various cd4 constructs with endocytosis rates of between 0.2 and 30%/min in a quantitative infectious focus assay. for a number of laboratory-adapted hiv-1 and hiv-2 strains, the highest levels of infection were found on cells with very limited cd4 endocytosis, while cells with efficient cd4 uptake were only poorly infectable, suggesting that cd4 internaliz ... | 1995 | 7494343 |
| interface peptides as structure-based human immunodeficiency virus reverse transcriptase inhibitors. | reverse transcriptases from both human immunodeficiency viruses type 1 and 2 are obligatory dimers. a tryptophan-rich repeat motif that is highly conserved between these proteins, as well as in the reverse transcriptase from simian immunodeficiency virus, has been postulated to be involved in hydrophobic subunit interactions. a synthetic 19-mer peptide covering part of this tryptophan repeat motif was recently shown to inhibit human immunodeficiency viruses type 1 reverse transcriptase subunit d ... | 1995 | 7499382 |
| inactivation of human immunodeficiency virus type 1 reverse transcriptase by oltipraz: evidence for the formation of a stable adduct. | oltipraz (5-pyrazinyl-4-methyl-1,2-dithiole-3-thione), which is undergoing clinical evaluation as an anticarcinogen, also inhibits hiv-1 replication (ic50 approximately equal to 10 microm). the inactivation of rt appears to be a relevant antiviral mechanism since oltipraz blocks viral replication in acutely infected t-cell lines, but is ineffective in chronically infected ach-2 cells (h. j. prochaska, w. g. bornmann, p. baron, and b. polsky (1995) mol. pharmacol. 48, 15-20). since a nucleophilic ... | 1995 | 7503549 |
| evaluation of a rapid assay system, hiv 1/hiv 2 testpack, abbott, to detect human immunodeficiency virus antibodies in postmortem blood. | for evaluating the hiv 1/hiv 2 testpack (abbott, chicago, il) to detect antibodies to human immunodeficiency virus (hiv) in whole postmortem blood 456 samples were collected prior forensic autopsies. all samples were tested using the enzyme-linked immunoassay (elisa) and the testpack; positively reactive samples and samples with equivocal results were confirmed by western blot. of the 456 samples 21 (4.6 per cent) proved to be reactive in both systems (confirmed by western blot). in 17 cases (3. ... | 1995 | 7876792 |
| multisite evaluation of four anti-hiv-1/hiv-2 enzyme immunoassays. australian hiv test evaluation group. | the performance of four enzyme immunoassays, manufactured by abbott, diagnostics pasteur, genetic systems, and organon teknika, for the combined detection of anti-human immunodeficiency virus type 1 (hiv-1) and anti-hiv-2, was examined in a multisite evaluation. the collaborative efforts of 7 australian red cross blood transfusion and 12 australian public health laboratories minimized potential biases in data by providing large numbers of anti-hiv-1-negative and -positive samples. sensitivity wa ... | 1995 | 7882108 |
| proteolytic processing of particle-associated retroviral polyproteins by homologous and heterologous viral proteinases. | retroviral proteinase(pr)-catalyzed cleavage of the viral gag and gag-pol polyproteins within the nascent virus particle is required for productive viral infection. kinetic characterization and specificity analyses have been reported for several retroviral pr using oligopeptide substrates. in this study, we performed a comparative analysis of pr from avian, bovine, simian and human retroviruses using polyproteins of human immunodeficiency virus (hiv) type 1 or avian leukosis virus as substrates. ... | 1995 | 7883003 |
| progression to aids in the absence of a gene for vpr or vpx. | rhesus monkeys (macaca mulatta) were experimentally infected with strains of simian immunodeficiency virus (siv) derived from sivmac239 lacking vpr, vpx, or both vpr and vpx genes. these auxiliary genes are not required for virus replication in cultured cells but are consistently conserved within the sivmac/human immunodeficiency virus type 2/sivsm group of primate lentiviruses. all four rhesus monkeys infected with the vpr deletion mutant showed an early spike in plasma antigenemia, maintained ... | 1995 | 7884883 |