Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| sequence specific binding of the transcription factor c-ets1 to the human immunodeficiency virus type i long terminal repeat. | human immunodeficiency virus type i (hiv-1) long terminal repeat (ltr) driven transcription is regulated by a variety of cellular transcription factors. most work has focused on the two nuclear factor kappa b (nf-kb) elements indispensable for hiv-1 ltr enhancer function. we demonstrate here the specific binding of the transcription factor c-ets1 to an u3 region of the hiv-1 ltr (nt -141 to -149) using electrophoretic mobility shift analysis with t-cell nuclear extract and in vitro translated pr ... | 1993 | 8280137 |
| the human immunodeficiency virus type 1 (hiv-1) vif protein is located in the cytoplasm of infected cells and its effect on viral replication is equivalent in hiv-2. | the human immunodeficiency virus type 1 (hiv-1) vif gene (viral infectivity gene) plays an important role in viral replication in vitro. we demonstrated that the vif protein is membrane associated in hiv-1-infected cells and have investigated the role in viral replication of the equivalent gene in hiv-2. we constructed an hiv-2 vif minus mutant and studied its virulence and cellular tropism in vitro. parallel experiments were also performed with an hiv-1 vif mutant to ascertain whether the two d ... | 1993 | 8280477 |
| specificity of antibody-dependent cellular cytotoxicity in sera from human immunodeficiency virus type 2-infected individuals. | adcc activity in sera from hiv-2-infected individuals was monitored against hiv-1iiib, sivmac, and three different hiv-2 strains. the sera mediated adcc against the hiv-2 strains in high frequencies and reacted equally well with sivmac, whereas no cross-reactivity was seen against hiv-1iiib. the degree of antigenic similarities between the virus strains was also evaluated in order to estimate the variability of adcc target regions. the sivmac strain and two of the hiv-2 strains were antigenicall ... | 1993 | 7504937 |
| an antibody that binds the immunoglobulin cdr3-like region of the cd4 molecule inhibits provirus transcription in hiv-infected t cells. | we used the polymerase chain reaction (pcr) to study which step(s) of the human immunodeficiency virus type 1 (hiv-1) life cycle may be blocked following treatment of hiv-exposed cem cells with 13b8-2, a monoclonal antibody (mab) specific for the immunoglobulin (ig) cdr3-like region of the cd4 molecule and able to inhibit the productive infection of cem cells by hiv-1. the presence of viral rna was investigated and found in 13b8-2 mab-treated cem cells 30 min after viral exposure; the full-lengt ... | 1993 | 7505220 |
| viral resistance to the thiazolo-iso-indolinones, a new class of nonnucleoside inhibitors of human immunodeficiency virus type 1 reverse transcriptase. | thiazolo-iso-indolinone derivatives with high specificity toward the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1) were identified. the most potent compound, bm +51.0836, inhibited hiv-1 rt at a 50% inhibitory concentration of 90 nm in vitro. in cell culture assays, similar 50% inhibitory concentrations were obtained with high specificity for hiv-1. these substances were equally active against a zidovudine-resistant isolate. no antiviral effect was observed with an hi ... | 1993 | 7509144 |
| hiv seropositivity in nigerians with lymphoproliferative malignancies. | one hundred and four nigerians with lymphoproliferative malignancies were tested for antibodies to human immunodeficiency virus types 1 and 2 (hiv-1 and 2). all the patients with high grade lymphomas in this series were seronegative for hiv-1 and 2. only 1 of the 104 patients had antibody to hiv-1 and none had antibody to hiv-2. although the single positive result would suggest a higher hiv-1 seropositivity rate among the patients compared with the general nigerian population, it should be inter ... | 1993 | 7839934 |
| analysis of human immunodeficiency virus type 1 nef gene sequences present in vivo. | the nef genes of the human immunodeficiency viruses type 1 and 2 (hiv-1 and hiv-2) and the related simian immunodeficiency viruses (sivs) encode a protein (nef) whose role in virus replication and cytopathicity remains uncertain. as an attempt to elucidate the function of nef, we characterized the nucleotide and corresponding protein sequences of naturally occurring nef genes obtained from several hiv-1-infected individuals. a consensus nef sequence was derived and used to identify several featu ... | 1993 | 8043040 |
| novel, negatively charged, human serum albumins display potent and selective in vitro anti-human immunodeficiency virus type 1 activity. | we prepared a series of modified proteins and peptides by derivatizing the positively charged epsilon-amino groups of the lysine amino acids through reaction with anhydrides of succinic acid (suc) and aconitic acid (aco). human serum albumin (hsa) was modified by introduction of a single carboxylic group (suc-hsa) or two carboxylic groups (aco-hsa) per amine function, yielding strongly negatively charged compounds. the in vitro anti-human immunodeficiency virus (hiv)-1 ic50 of suc-hsa was about ... | 1993 | 7902528 |
| cellular and plasma viral load in patients infected with hiv-2. | to determine circulating viral load in hiv-2-infected individuals. | 1993 | 7904166 |
| the role of cd4 in hiv binding and entry. | the primary cellular receptor for the human and simian immunodeficiency viruses hiv-1, hiv-2 and siv is the cd4 antigen (sattentau et al. 1988; sattentau & weiss 1988). hiv infection of cd4+ cells is initiated by binding of the virus to the cell surface, via a high-affinity interaction between the first domain of cd4 and the hiv outer envelope glycoprotein, gp120. the use of a soluble recombinant form of cd4 (scd4) as a receptor mimic has simplified the analysis of receptor binding and post-bind ... | 1993 | 7904348 |
| is cd4 sufficient for hiv entry? cell surface molecules involved in hiv infection. | hiv-1, hiv-2 and siv each bind to cd4 as the first step in virus entry. however, alternative receptors may also be used. hiv-1 binds to glycolipids with terminal galactosylceramide residues on neural cells; opsonized virus binds to fc receptors; hiv-2 can infect certain cd4-negative cells. further receptors may also play a role in cd4-mediated infection, including cell adhesion molecules and possibly cell surface proteinases. after binding to cd4, immunodeficiency viruses require secondary molec ... | 1993 | 7904349 |
| mhc-i non-restricted cytotoxic activity in macaca sylvana experimentally inoculated with hiv2 and siv/mac. | the anti-retrovirus cell-mediated immunity was repeatedly investigated in seven monkeys (macaca sylvana). four of these animals were injected with cell-free supernatants containing human immunodeficiency viruses: two monkeys received hiv1 bru (2.5 x 10(6) cpm), two received hiv2 rod (1.5 x 10(6) cpm). two additional animals were injected with a cell-free supernatant containing simian immunodeficiency virus siv/mac 251 (1.5 x 10(6) cpm) and the last animal served as control. the four macaques inf ... | 1993 | 7905683 |
| infections among pygmies in the eastern province of cameroon. | the health requirements of pygmies is poorly understood because of their continued isolation from the other tribes in central africa. this study was undertaken among the baka pygmies of the eastern province of cameroon to generate basic health data among them. a total of 141 adults (18-45 years) were tested for the hepatitis b surface antigen (hbsag), antibody to the surface antigen (anti-hbs), antibody to the core antigen (anti-hbc) and antibody to the hepatitis c virus (anti-hcv). all hbsag-po ... | 1993 | 7907163 |
| multi-branched peptides based on the hiv-1 v3 loop consensus motif inhibit hiv-1 and hiv-2 infection in cd4+ and cd4- cells. | the v3 loop is an hypervariable region of the hiv-1 surface envelope glycoprotein gp120 that is able to generate neutralizing antibodies. these antibodies are generally type-specific. they inhibit the interaction between the v3 loop and the membrane molecules involved in virus-cell and cell-cell fusion. synthetic peptides based on the v3 loop sequence have been tentatively used to block the fusion process, but the results were unsuccessful. in this report, we confirm that monomeric v3 peptides a ... | 1993 | 7916261 |
| ultrastructural correlation between follicular dendritic cells and the frequency of virus-like particles during the lymph nodes reaction of siv/hiv 2 infected cynomolgus monkeys. | lymph nodes from 18 siv/hiv2 infected monkeys developing a severe aids-like disease were studied by electron microscopy. the lesions were correlated with the histopathologic staining and the anti-sivp28 immunostaining. the investigation of follicular dendritic cells (fdc) and associated retroviral particles was focused on the light zones of germinal centres during the follicular hyperplasia, fragmentation atrophy and depletion. fdcs were mostly developed in the first two stages, while the highes ... | 1993 | 7849288 |
| fine mapping of hiv-1 nef-epitopes by monoclonal antibodies. | a panel of newly isolated murine monoclonal antibodies is described which are specific for the nef protein of the human immunodeficiency virus type 1 (hiv-1). epitope mapping using recombinant nef-related proteins, synthetic peptides and lipopeptides showed 3 independent antigenic determinants located within the regions of amino acids 83-93, 175-190 and 86-166 of the nef protein. none of the monoclonal antibodies reacted with recombinant nef proteins of hiv-2. | 1993 | 7678193 |
| morphometric analysis of envelope glycoprotein gp120 distribution on hiv-1 virions. | the surface of hiv-1, like that of other retroviruses, is studied with virally encoded glycoproteins which appear ultrastructurally as electron-dense spikes or knobs. the glycoprotein that forms the spike structure, gp120, is non-covalently bound to the transmembrane glycoprotein gp41. mature hiv-1 virions do not have as many spikes as the genetically related retroviruses hiv-2 and siv. gp120 is lost from hiv-1 during viral morphogenesis and after incubation of the virus with the soluble form of ... | 1993 | 7678271 |
| human immunodeficiency virus type 1-specific [2',5'-bis-o-(tert- butyldimethylsilyl)-beta-d-ribofuranosyl]-3'-spiro-5"-(4"-amino-1",2"- oxathiole-2",2"-dioxide)-purine analogues show a resistance spectrum that is different from that of the human immunodeficiency virus type 1-specific non-nucleoside analogues. | the [2',5'-bis-o-(tert-butyldimethylsilyl)-beta-d-ribofuranosyl]-3'- spiro-5"-(4"-amino-1",2"-oxathiole-2",2"-dioxide) (tsao) derivatives of n1-methylhypoxanthine with linkage to the tsao moiety through the n9 or n7 atom of the hypoxanthine ring (designated tsao-m1hx and 7-tsao-m1hx, respectively) are potent and selective inhibitors of human immunodeficiency virus type 1 (hiv-1) but not hiv-2 or simian immunodeficiency virus. their selectivity indices (ratio of cytotoxic concentration to antivir ... | 1993 | 7678689 |
| specificity of antibodies produced against native or desialylated human immunodeficiency virus type 1 recombinant gp160. | in a previous report we have shown that, in contrast to antibodies produced against native or fully deglycosylated human immunodeficiency virus type 1 (hiv-1) gp160 in rabbits, antibodies raised against desialylated hiv-1 gp160 also recognize gp140 from hiv-2 at high titers. here, we characterize the fine specificity of these cross-reactive antibodies. inhibition assays with a panel of synthetic peptides as competitors showed that cross-reactivity to gp140 was due to antibodies that were specifi ... | 1993 | 7679751 |
| epitopes of human immunodeficiency virus regulatory proteins tat, nef and rev are expressed in skin in atopic dermatitis. | we extend our previous documentation that epitopes of hiv regulatory proteins tat, rev, and nef are expressed in tissue from uninfected individuals by the immunohistochemical analysis of normal skin (n = 10) and skin in some selected inflammatory dermatoses including urticaria (n = 6), systemic lupus erythematosus (n = 6), and atopic dermatitis (affected skin, n = 10, and after epicutaneous patch test for allergens, n = 8). a rabbit antibody to hiv-2 tat did not show immunolabeling of skin. bloo ... | 1993 | 7680253 |
| analysis of nonnucleoside drug-resistant variants of human immunodeficiency virus type 1 reverse transcriptase. | a number of chemically distinct nonnucleoside inhibitors of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt) have been reported. several lines of evidence, including the isolation of rt mutants that show cross resistance, suggest that, despite their structural diversity, many of these inhibitors bind to a common site on hiv-1 rt. we have recently reported that, on the basis of analyses of hiv-1/hiv-2 chimeras, the natural product calanolide a may interact with a different s ... | 1993 | 7680393 |
| potent and highly selective human immunodeficiency virus type 1 (hiv-1) inhibition by a series of alpha-anilinophenylacetamide derivatives targeted at hiv-1 reverse transcriptase. | in vitro evaluation of a large chemical library of pharmacologically acceptable prototype compounds in a high-capacity, cellular-based screening system has led to the discovery of another family of human immunodeficiency virus type 1 (hiv-1) inhibitors. through optimization of a lead compound, several alpha-anilinophenylacetamide (alpha-apa) derivatives have been identified that inhibit the replication of several hiv-1 strains (iiib/lai, rf, ndk, mn, he) in a variety of host cell types at concen ... | 1993 | 7680476 |
| [non-radioisotopic reverse transcriptase assay using biotin-11-deoxyuridine-triphosphate and a primer-immobilized microtiter plate: application for detection and identification of isolated retroviruses from hiv-1-seropositive hemophiliac patients]. | non-radioisotopic reverse transcriptase assay (non-rta) was successfully applied for detection and identification of the retroviruses isolated from peripheral mononuclear cells from eight hiv-1-seropositive hemophiliac patients. of 40 samples, 36 (90%) were consistent in detection between non-ri and ri rta. four samples which showed rt activities slightly above the cutoff level of ri rta were not detected by non-ri rta. non-specific rt-inhibitors in the culture supernatant decreased the sensitiv ... | 1993 | 7680705 |
| the fidelity of the reverse transcriptases of human immunodeficiency viruses and murine leukemia virus, exhibited by the mispair extension frequencies, is sequence dependent and enzyme related. | sequence variations in hiv-1 and hiv-2 probably result in part from inaccurate dna synthesis by viral reverse transcriptases (rts). we have studied in vitro the fidelity of both the dna- and rna-dependent dna polymerization functions of the two hiv rts, as compared to that of murine leukemia virus (mlv) rt. the two hiv rts were less accurate than mlv rt. the mispair extension frequencies observed previously with ribosomal rna (rrna) template were higher than those detected with phi x174am3 dna t ... | 1993 | 7681015 |
| steady-state kinetic studies with the non-nucleoside hiv-1 reverse transcriptase inhibitor u-87201e. | the multifunctional hiv-1 rt (human immunodeficiency virus type 1-reverse transcriptase) enzyme possesses three main functions including the rna- and dna-directed dna polymerases and the rnase h. the bisheteroarylpiperazine u-87201e inhibits the two polymerase functions but not the rnase h. enzymatic kinetic studies of the hiv-1 rt-catalyzed rna- and dna-directed dna polymerase activities were carried out in order to determine if the inhibitor interferes with either the template:primer or the de ... | 1993 | 7681060 |
| two highly antigenic sites in the human immunodeficiency virus type 1 reverse transcriptase. | antibodies to human immunodeficiency virus type 1 (hiv-1) reverse transcriptase (rt) are found in the serum of the majority of infected individuals, and inhibition of rt polymerase activity by hiv-1-positive sera can be demonstrated in vitro. the binding sites of human antibodies on the protein have not yet been identified. we synthesized overlapping peptides covering the entire rt protein of hiv-1 and used them in an enzyme-linked immunosorbent assay system to map the reactivities of hiv-1 and ... | 1993 | 7681439 |
| identification of four antibody-binding sites in the envelope proteins of simian immunodeficiency virus, sivsm. | to identify antigenic regions in the envelope glycoproteins of the simian immunodeficiency virus isolate, sivsm. | 1993 | 7682082 |
| cr1 (cd35) and cr3 (cd11b/cd18) mediate infection of human monocytes and monocytic cell lines with complement-opsonized hiv independently of cd4. | peripheral blood and tissue mononuclear phagocytes serve as major viral reservoirs in hiv-infected individuals. we investigated the role of complement receptors cr1 (cd35) and cr3 (cd11b/cd18) in mediating productive infection with complement-opsonized hiv-1 and hiv-2 of cultured normal human peripheral blood monocytes, the promonocytic cell line thp-1, the monocytic cell line mono mac 6 and the glial cell line u251-mg. cells were infected with the htlv-iiib strain of hiv-1 or the lav-2 strain o ... | 1993 | 7682158 |
| generation and characterization of murine monoclonal antibodies reactive against n-terminal and other regions of hiv-1 reverse transcriptase. | we produced a series of monoclonal antibodies against the human immunodeficiency virus (hiv-1) reverse transcriptase by immunizing mice with either purified recombinant hiv-1 p66 protein or with recombinant vaccinia virus which expresses hiv-1 pol sequences. the antibodies generated were specific for the reverse transcriptase protein, and recognized only the p51 and p66 subunits of the enzyme in each of the hiv-1 viral lysates and lysates of hiv-1 infected cells. the antibodies did not cross-rea ... | 1993 | 7682257 |
| a virion-specific inhibitory molecule with therapeutic potential for human immunodeficiency virus type 1. | a potential new approach for gene therapy against human immunodeficiency virus type 1 (hiv-1) infection is the design of a nonstructural gene-based virion-specific inhibitory molecule that is packaged with virus to destroy its infectivity. we tested this approach for hiv-1 by using vpx, a virion-associated protein of hiv-2 and simian immunodeficiency virus. vpx was incorporated into hiv-1 virions and the resulting cell-free virus lost infectivity in cd4+ human t cells. this demonstrates the ther ... | 1993 | 7682710 |
| hiv-1-specific rt inhibitors: highly selective inhibitors of human immunodeficiency virus type 1 that are specifically targeted at the viral reverse transcriptase. | the tibo, hept, nevirapine, pyridinone, bhap, tsao, and alpha-apa derivatives, although belonging to structurally diverging classes of molecules, share remarkable common features. they are specifically active against the reverse transcriptase of hiv-1 (tibo and hept also, to a certain extent, against the reverse transcriptase of sivagm strains), but not against the reverse transcriptases of hiv-2 or any other retroviruses. nor are they active against any of the cellular dna polymerases. these hi ... | 1993 | 7683360 |
| the interaction of illimaquinone, a selective inhibitor of the rnase h activity, with the reverse transcriptases of human immunodeficiency and murine leukemia retroviruses. | illimaquinone, a natural marine product, was shown by us to inhibit preferentially the ribonuclease h (rnase h) activity of the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1). we have also shown that illimaquinone inhibits the rnase h activity of hiv-2 rt in addition to that of hiv-1 rt, murine leukemia virus rt, and escherichia coli rnase h. chemical modifications of hiv-1 rt by sulfhydryl-specific reagents, such as n-ethylmaleimide (nem) have been demonstrated to spe ... | 1993 | 7683648 |
| diarylsulfones, a new chemical class of nonnucleoside antiviral inhibitors of human immunodeficiency virus type 1 reverse transcriptase. | a series of variously substituted diarylsulfones and related derivatives were found to prevent human immunodeficiency virus type 1 (hiv-1) replication and hiv-1-induced cell killing in vitro. one of the more potent derivatives, 2-nitrophenyl phenyl sulfone (npps), completely protected human cem-ss lymphoblastoid cells from the cytopathic effects of hiv-1 in cell culture at 1 to 5 microm concentrations. hiv-1 replication, as assessed by the production of infectious virions, viral p24 antigen, and ... | 1993 | 7684215 |
| enzyme-linked immunosorbent assays for the measurement of human immunodeficiency virus, type 1 reverse transcriptase antigen and antibodies. | enzyme-linked immunosorbent assays (elisa), using recombinant hiv-1 reverse transcriptase (rt; p66), are described for the measurement of rt antigen and serum antibodies to rt (anti-rt). the elisa for anti-rt was developed in qualitative and quantitative forms, both were highly specific (100%, 0/859; 99.6%, 3/859), the former was sensitive (100%, 364/364) detecting the highest dilution of a standard high titre anti-hiv-1 rt antibody positive control serum. the latter was less sensitive (97.2%, 3 ... | 1993 | 7684387 |
| activity of triciribine and triciribine-5'-monophosphate against human immunodeficiency virus types 1 and 2. | triciribine (tcn) and its 5'-monophosphate (tcn-p) are novel tricyclic compounds with known antitumor activity; tcn-p is currently in phase ii human clinical trials. we now report that these compounds have potent and selective activity against hiv-1 and hiv-2. using a syncytial plaque assay, tcn and tcn-p were active against hiv-1 at 0.01-0.02 microm and had differential selectivities of 2250 and 1900, respectively, compared to 1850 for azt. in contrast, tcn and tcn-p had minimal selectivity aga ... | 1993 | 7685612 |
| specific inhibition of the reverse transcriptase of human immunodeficiency virus type 1 and the chimeric enzymes of human immunodeficiency virus type 1 and type 2 by nonnucleoside inhibitors. | we have studied the effects of four nonnucleoside inhibitors, including the novel natural product inhibitor calanolide a, on molecular chimeras containing complementary segments of human immunodeficiency virus type 1 (hiv-1) and type 2 (hiv-2) reverse transcriptases (rts). all four compounds specifically inhibited the dna polymerase activity of hiv-1 rt but had no apparent effect on the rnase h activity of this enzyme or on the dna polymerase or rnase h activity of hiv-2 rt. three of these compo ... | 1993 | 7685994 |
| the quinoline u-78036 is a potent inhibitor of hiv-1 reverse transcriptase. | the quinoline u-78036 represents a new class of non-nucleoside human immunodeficiency virus (hiv)-1 reverse transcriptase inhibitors. the agent possesses excellent antiviral activity at nontoxic doses in hiv-1-infected lymphocytes grown in tissue culture. enzymatic kinetic studies of the hiv-1 reverse transcriptase (rt)-catalyzed rna-directed dna polymerase function were carried out in order to determine whether the inhibitor interacts with the template-primer or deoxyribonucleotide triphosphate ... | 1993 | 7686907 |
| amino acid substitutions in hiv-1 reverse transcriptase with corresponding residues from hiv-2. effect on kinetic constants and inhibition by non-nucleoside analogs. | nevirapine is a highly potent and specific inhibitor of human immunodeficiency virus type 1 (hiv-1) polymerase, but is inactive against hiv-2 and other polymerase. previous studies demonstrated that residues 176-190 of hiv-1 reverse transcriptase (rt) can confer nevirapine sensitivity to hiv-2 rt. to better characterize the role of this sequence in hiv-1 rt, we have progressively substituted residues 176-190 of hiv-2 rt for those of hiv-1 rt and monitored the impact on the kinetic properties; in ... | 1993 | 7688367 |
| detection of simian immunodeficiency virus and human immunodeficiency virus type 2 capsid antigens by a monoclonal antibody-based antigen capture assay. | we have tested the ability of a monoclonal antibody-based simian immunodeficiency virus (siv) p27 capsid antigen assay to detect siv antigen in supernatants from a variety of infected cell cultures. the antigen capture assay has a sensitivity of approximately 30 pg of siv p27 capsid antigen/ml. the assay detected siv p27 capsid antigen in cell culture supernatants from all six strains tested, detected the replication of siv following the inoculation of the virus in peripheral blood mononuclear c ... | 1993 | 7688521 |
| comparative humoral responses to human immunodeficiency virus type 1-p24gag linear b-cell epitopes among individuals showing atypical western immunoblotting reactions and implications for diagnosis. | serum specimens from 25 individuals with an isolated human immunodeficiency virus type 1 (hiv-1) core antigen reactivity in a western immunoblot test were examined for their reactivities with hiv-1 virions, control cellular antigens, hiv-1-bru p24gag recombinant protein (p24gag), and a panel of 22 p24gag-derived peptides. the results were as follows: (i) serum specimens from eight hiv-1-uninfected subjects did bind to virions but failed to bind to p24gag; (ii) sera from 13 hiv-1-uninfected subje ... | 1993 | 7688755 |
| cytotoxic t cells in hiv2 seropositive gambians. identification of a virus-specific mhc-restricted peptide epitope. | a preliminary study of gag-specific, mhc-restricted cd8+ ctl has been performed in nine gambian patients infected with hiv2. such ctl were present in at least 55% of patients in fresh peripheral blood mononuclear cells without the requirement for in vitro restimulation. we have identified a nonamer peptide from hiv2 gag that is recognized by cd8+ hla-b53 ctl using an amino acid sequence motif predicted from analysis of endogenous peptides eluted from hla-b53 molecules. this peptide, from an hiv2 ... | 1993 | 7690804 |
| activity of a novel quinoxaline derivative against human immunodeficiency virus type 1 reverse transcriptase and viral replication. | s-2720 [6-chloro-3,3-dimethyl-4-(isopropenyloxycarbonyl)-3,4- dihydroquinoxalin-2(1h)-thione], a quinoxaline derivative, was found to be a very potent inhibitor of both human immunodeficiency virus type 1 reverse transcriptase (hiv-1 rt) activity and hiv-1 replication in tissue culture. like other nonnucleoside rt inhibitors, s-2720 does not affect the hiv-2 rt. a s-2720-resistant virus was selected and shown to possess a mutation within the rt-coding region that has not previously been describe ... | 1993 | 7692812 |
| thiazolobenzimidazole: biological and biochemical anti-retroviral activity of a new nonnucleoside reverse transcriptase inhibitor. | thiazolobenzimidazole (nsc 625487) was a highly potent inhibitor of human immunodeficiency virus-induced cell killing and viral replication in a variety of human cell lines, as well as fresh human peripheral blood lymphocytes and macrophages. the compound was active against a panel of biologically diverse laboratory and clinical strains of hiv-1, including the azt-resistant strain g910-6. however, the agent was inactive against hiv-2 and a pyridinone-resistant strain (a17) of hiv-1, a strain whi ... | 1993 | 7692815 |
| isolation and characterization of monoclonal antibodies raised against the reverse transcriptase of human immunodeficiency virus type 2 and cross-reactivity with that of type 1. | monoclonal antibodies to human immunodeficiency virus (hiv)-2 reverse transcriptase have been raised with the ultimate goal of generating fab fragments for future co-crystallization studies. a number of mouse monoclonal antibodies to recombinant hiv-2 reverse transcriptase have been obtained and characterized in terms of the possible epitopes they recognise together with cross-reactivity with a related reverse transcriptase. the antibodies were shown to fall into three groups that recognize diff ... | 1993 | 7693912 |
| conformational changes induced in the envelope glycoproteins of the human and simian immunodeficiency viruses by soluble receptor binding. | we have investigated the molecular basis of biological differences observed among cell line-adapted isolates of the human immunodeficiency virus types 1 and 2 (hiv-1 and hiv-2) and the simian immunodeficiency virus (siv) in response to receptor binding by using a soluble form of cd4 (scd4) as a receptor mimic. we find that scd4 binds to the envelope glycoproteins of all of the hiv-1 isolates tested with affinities within a threefold range, whereas those of the hiv-2 and siv isolates have relativ ... | 1993 | 7693970 |
| generation, characterization and cross-reactivities of monoclonal antibodies against the p24 core protein and the gp130 envelope glycoprotein of hiv-2ben. | the purpose of this study was to characterize antigenic determinants on structural polypeptides of human immunodeficiency virus type 2 (hiv-2ben). therefore, three hiv-2-specific monoclonal antibodies (mabs) against the p24 core protein (gag) and one mab against the gp130 envelope glycoprotein (env) were produced. in addition to p24 the anti-core mabs recognized the primary translation product of the viral gag gene p55 and an intermediate cleavage product p41. core mabs cross-reacted with anothe ... | 1993 | 7694060 |
| expression and mutational analysis of the reverse transcriptase of the lentivirus equine infectious anemia virus. | the reverse transcriptase of equine infectious anemia virus (eiav) shows sequence similarity with the reverse transcriptases of other lentiviruses, particularly with those of human immunodeficiency viruses types 1 and 2 (hiv-1 and hiv-2). we have constructed a plasmid that when introduced into e. coli induces the synthesis of substantial quantities of the nearly authentic eiav reverse transcriptase. the viral and bacterially expressed reverse transcriptases are similar in their molecular weights ... | 1993 | 7694581 |
| boehringer mannheim modular test concepts in hiv and hepatitis immunoassays. | anti-hiv-antibody and hepatitis c virus (hcv)-antibody screening tests have to be able to detect a variety of virus antibodies. on the other hand, hiv-antigen specific antibody tests that detect only one kind of antibody are needed for prognosis of disease or for distinguishing infection by different virus subtypes. usually in an enzyme-linked immunosorbent assay for each individual test an individual solid phase has to be created. for our boehringer mannheim enzymun-test diagnostics assay we us ... | 1993 | 7694814 |
| an aids test that travels well. | a new dipstick test will enable health workers in remote third world communities to screen blood for human immunodeficiency virus (hiv) and monitor the spread of hiv infection. the test, developed by the program for appropriate technology in health (path), works without electricity, instrumentation, or cold chain and is locally manufacturable. results are available in 20 minutes, and the cost is 25 cents per sample. antibodies to both hiv-1 and hiv-2 are detectable. in the test, a plastic dip ... | 1993 | 12286975 |
| are seroepidemiological surveys for human immunodeficiency virus infection based on tests on pools of serum specimens accurate and cost-effective? | serum specimens (n = 17668) from uk antenatal patients in the thames regions were tested by wellcozyme hiv 1/2 eia singly and in pools of 6, 12 and 24: 35 (0.2%, 1 in 505) were confirmed as anti-hiv positive. the pools of 12 were also tested for anti-hiv 1/2 by iaf biochem, behring and diagnostics pasteur eias. all 35 positive specimens were easily detectable after pooling in groups of 12. the false positive rate for wellcozyme was nearly halved compared with individual testing (1 in 309 false p ... | 1993 | 15566730 |
| [laboratory tests for the diagnosis of human immunodeficiency virus infection]. | laboratory tests are essential for diagnosis and management of patients infected with hiv, for screening of blood donors, and for epidemiologic surveillance of hiv infection and aids. diagnosis of hiv infection is based on demonstration of antibodies against the virus, detection of viral antigens, isolation of the virus, or detection of genetic material in infected cells. tests that detect antibodies are the most frequently used because of their ease of use and relatively low cost. the elisa ... | 1992 | 12290619 |
| hiv infection and aids in china. | through november 1990, phlebotomists took serum samples from 305,280 people (32,093 of whom were foreigners) to determine the prevalence of hiv-1 infection and aids in china. the phlebotomists worked in the laboratory at the academy of preventive medicine in beijing, provincial health and antiepidemic stations, and other health institutions throughout china. the virology institute at the academy used the elisa, immunoenzymatic tests, gelatin particle agglutination test, or immunofluorescence t ... | 1992 | 12344005 |
| hiv-2: slower, still deadly. | hiv 2 transmission and prevalence in west africa are discussed. hiv 2 was first recognized in 1985 in senegal. prevalence in 1991 was highest in guinea-bissau, ivory coast, and burkina faso. the population at greatest risk is prostitutes and men who attend sexually transmitted disease (std) clinics, which populations have a 10 times greater prevalence than the general population. 8% of prostitutes in senegal are infected with hiv, 16% in burkina faso, and 9% in the general population of guin ... | 1992 | 12318129 |
| [neurological disorders associated with hiv infection]. | neurological diseases occur frequently in patients infected with human immunodeficiency virus (hiv). there are three main groups of central nervous system (cns) dysfunction: (1) direct effects of hiv; (2) opportunistic infections; (3) opportunistic neoplasms. on the basis of clinical characteristics it is possible to differentiate focal and diffuse pathologic alterations of cns. the starting point of evaluation of cns dysfunction is computed tomography (ct). if the focal lesions are not present ... | 1992 | 18170970 |
| what is a quasispecies? | a quasispecies is a well-defined distribution of mutants that is generated by a mutation-selection process. selection does not act on a single mutant but on the quasispecies as a whole. experimental systems have been designed to study quasispecies evolution under laboratory conditions. more recently, virus populations have been called quasispecies to indicate their extensive genetic heterogeneity. the most prominent examples are probably the human immunodeficiency viruses hiv-1 and hiv-2. the qu ... | 1992 | 21235976 |
| human immunodeficiency virus type 1 and type 2 protease monomers are functionally interchangeable in the dimeric enzymes. | human immunodeficiency virus type 1 (hiv-1) and hiv-2 proteases are dimers of identical subunits. we made a construct for the expression of recombinant one-chain hiv-2 protease dimer, which, like the previously described one-chain hiv-1 protease dimer, is fully active. the constructs for the one-chain dimers of hiv-1 and hiv-2 proteases were modified to produce hybrid one-chain dimers consisting of both hiv-1 and hiv-2 protease monomers. although the monomers share only 47.5% sequence identity, ... | 1992 | 1731102 |
| siv from stump-tailed macaques: molecular characterization of a highly transmissible primate lentivirus. | over the past 6 years, simian immunodeficiency viruses (sivs) have been isolated from four distinct species of macaques (macaca mulatta, m. fascicularis, m. nemestrina, and m. arctoides) in captivity in the united states. however, the epidemiologic and genetic relationships among sivs from the four species are not well understood. siv from stump-tailed macaques (m. arctoides) (sivstm) is unusual in that it has been associated with outbreaks of infection characterized by aggressive spread within ... | 1992 | 1733112 |
| human immunodeficiency virus type 2 envelope glycoprotein: differential cd4 interactions of soluble gp120 versus the assembled envelope complex. | utilizing a recombinant vaccinia expression system, we investigated the biological properties and cd4 receptor interactions of the envelope glycoproteins of a noncytopathic human immunodeficiency virus type 2 strain, termed hiv-2/st, and a highly cytopathic variant derived from it. the efficiency and host cell range of syncytium formation by the recombinant glycoproteins of both viruses were highly restricted compared to those of prototypic strains of hiv (hiv-2/rod or hiv-1/iiib). however, the ... | 1992 | 1736526 |
| lack of evidence of vertical transmission of human immunodeficiency virus type 2 in a sample of the general population in bissau. | twenty-nine human immunodeficiency virus type 2 (hiv-2) seropositive women identified in a cross-sectional study in bissau in 1987 participated in a follow-up study in 1988, where each was matched for age and marital status with two hiv-2 seronegative women. detailed information about all pregnancies was obtained. the hiv-2 seropositive women and their controls had similar mean numbers of pregnancies, live children, children who died, and abortions. the hiv-2 seropositive women did not have a gr ... | 1992 | 1738085 |
| activity of cd4-pseudomonas exotoxin against cells expressing diverse forms of the hiv and siv envelope glycoproteins. | cd4(178)-pe40 is a genetically engineered hybrid toxin containing a portion of human cd4 linked to the translocation and adp-ribosylation domains of pseudomonas exotoxin a. in vitro, the molecule has been shown to selectively kill cells expressing the envelope glycoproteins of human immunodeficiency virus (hiv) or simian immunodeficiency virus (siv), and to inhibit hiv spread. in this report we examine the activity of the hybrid toxin against cells expressing diverse forms of the hiv and siv env ... | 1992 | 1738090 |
| structural features in tar rna of human and simian immunodeficiency viruses: a phylogenetic analysis. | a comparative analysis of tar rna structures in human and simian immunodeficiency viruses reveals the conservation of certain structural features despite the divergence in sequence. both the tar elements of hiv-1 and siv-chimpanzee can be folded into relatively simple one-stem hairpin structures. chemical and rnaase probes were used to analyze the more complex structure of hiv-2 tar rna, which folds into a branched hairpin structure. a surprisingly similar rna conformation can be proposed for si ... | 1992 | 1738599 |
| improved detection of hiv-2 dna in clinical samples using a nested primer-based polymerase chain reaction. | a two-step polymerase chain reaction (pcr), with four double (nested) primer pairs, used for the detection of hiv-2 in clinical samples is described. with these four nested primer pairs we could detect hiv-2 dna in 17 of 17 virus isolates and in blood mononuclear cell samples from 31 of 37 (83.7%) seropositive individuals after ethidium bromide staining of the amplified dna. the nested primer pcr was also compared with a single primer pair-based pcr followed by hybridization. the sensitivities o ... | 1992 | 1740755 |
| the effects of cysteine mutations on the reverse transcriptases of human immunodeficiency virus types 1 and 2. | chemical modification of hiv-1 and hiv-2 (human immunodeficiency virus, types 1 and 2) reverse transcriptases (rt) with three thiol reactive compounds selectively inhibits the rnase h function of the enzyme. hiv-1 rt has 2 cysteines (at positions 38 and 280); hiv-2 rt has 3 (38, 280, 445). both of the cysteines in hiv-1 rt are in the polymerase domain. to investigate the role of the cysteines in the structure and function of the hiv rts, we have converted each cysteine to serine and made combina ... | 1992 | 1370463 |
| identification of b-cell antigenic sites on hiv-2 gp125. | synthetic peptides were used to identify continuous antigenic sites on the external envelope glycoprotein gp125 of human immunodeficiency virus (hiv)-2. initially, seven hiv-2-positive human serum samples were screened with 172 sequential nonapeptides containing a six-amino-acid overlap. this represents the entire gp125 molecule of hiv-2isy. the antibody reactivity was found to be mainly restricted to 14 regions within gp125. following these results, 33 longer peptides, 15-24 amino acids in leng ... | 1992 | 1370692 |
| role of mycoplasma infection in the cytopathic effect induced by human immunodeficiency virus type 1 in infected cell lines. | in addition to previously reported tetracycline analogs, other antibiotics known for antimycoplasmal activities inhibited the cytopathic effect in cem cl13 cells infected with human immunodeficiency virus type 1 (hiv-1) or hiv-2 but were unable to block virus replication. a contaminating mycoplasma was isolated from our cem cl13 cells and identified as a strain of mycoplasma fermentans. following infection of lymphoblastoid (cem) or promonocytic (u937 and thp1) cell lines with hiv-1, cytopathic ... | 1992 | 1371767 |
| detection of viral surface antigens on hiv-2ben infected human tumor cell lines by flow cytometry. | the human monocytic cell line u-937 clone 2 and two t-cell lines cem and molt-4 clone 8 were infected with hiv-2ben, a recent isolate of hiv-2. infection and subsequent antigen expression on the cell surface was monitored by flow cytometry using a rabbit-anti-serum against tween-ether-treated hiv-2ben and a fluorescein-isothiocyanate-conjugated igg against rabbit-igg. the sensitivity of the three cell lines to infection with hiv-2ben correlated with the percentages of cd4-expressing cells but no ... | 1992 | 1374306 |
| cross-neutralization of human immunodeficiency virus type 1 and 2 and simian immunodeficiency virus isolates. | in contrast to infrequent and low-titer cross-neutralization of human immunodeficiency virus type 1 (hiv-1) isolates by hiv-2- and simian immunodeficiency virus (siv)-positive sera, extensive cross-neutralization of hiv-2nih-z, sivmac251, and sivagm208k occurs with high titer, suggesting conservation of epitopes and mechanism(s) of neutralization. the v3 regions of hiv-2 and siv isolates, minimally related to the hiv-1 homolog, share significant sequence homology and are immunogenic in monkeys a ... | 1992 | 1374810 |
| 2',5'-bis-o-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino-1'',2''- oxathiole-2'',2'-dioxide)pyrimidine (tsao) nucleoside analogues: highlyselective inhibitors of human immunodeficiency virus type 1 that are targeted at the viral reverse transcriptase. | a series of pyrimidine nucleoside analogues containing [2',5'-bis-o-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino- 1'',2''-oxathiole-2'',2''-dioxide)]-beta-d-ribofuranose as the pentose were found to inhibit human immunodeficiency virus type 1 [hiv-1(iiib)] replication at a concentration of 0.06-0.8 microm but were not cytotoxic at a 1000- to 10,000-fold higher concentration. these nucleoside derivatives were also effective against various other hiv-1 strains, including those resistant to 3' ... | 1992 | 1374900 |
| resistance of human immunodeficiency virus type 1 reverse transcriptase to tibo derivatives induced by site-directed mutagenesis. | the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1) is the target enzyme for the tetrahydro-imidazo[4,5,1-jk][1,4]- benzodiazepin-2(1h)one and thione (tibo) derivatives, a class of highly potent and selective anti-hiv agents that specifically inhibit hiv-1 but not hiv-2 replication. the amino acid sequence divergence may be held responsible for the differential sensitivity of hiv-1 rt and hiv-2 rt to the tibo derivatives. using site-directed mutagenesis, we have introdu ... | 1992 | 1374986 |
| novel non-nucleoside inhibitors of hiv-1 reverse transcriptase. 2. tricyclic pyridobenzoxazepinones and dibenzoxazepinones. | dibenz[b,f][1,4]oxazepin-11(10h)-ones (iii), pyrido[2,3-b][1,4]benzoxazepin-6(5h)-ones (iv), and pyrido[2,3-b]- [1,5]benzoxazepin-5(6h)-ones (v) were found to inhibit human immunodeficiency virus type 1 reverse transcriptase with ic50 values as low as 19 nm. a-ring substitution has a profound effect on activity, with appropriate substituents at the positions ortho and para to the lactam nitrogen providing dramatically enhanced potency. substitution in the c-ring is generally neutral or detriment ... | 1992 | 1375293 |
| pcr amplification of large genomic fragments from human and simian immunodeficiency virus infected cell lines. | polymerase chain reaction (pcr) has been used to amplify the large fragments from viral genomic dna of siv from wild caught, asymptomatic erythrocebus monkeys from western africa (senegal) and also from hiv-2 infected cell lines. by using consensus primer sequences from highly conserved stretches of gag, pol and env genes, two halves of the viral genome of hiv-2 and siv (isolated from west african erythrocebus monkeys) have amplified by pcr. one half spans 5200 bp from within the u3 region of th ... | 1992 | 1375701 |
| kinetics of inhibition of human immunodeficiency virus type 1 (hiv-1) reverse transcriptase by the novel hiv-1-specific nucleoside analogue [2',5'-bis-o-(tert-butyldimethylsilyl)-beta-d-ribofuranosyl]-3'-spiro-5 "- (4"-amino-1",2"-oxathiole-2",2"-dioxide)thymine (tsao-t). | [2',5'-bis-o-(tert-butyldimethylsilyl)-beta-d-ribofuranosyl]-3'-spiro- 5"-(4"-amino-1",2"-oxathiole-2", 2"-dioxide)thymine (tsao-t) is a representative of a novel class of nucleoside analogues that are endowed with a potent and specific activity against human immunodeficiency virus (hiv) type 1 and are targeted at the hiv-1 reverse transcriptase (rt). inhibition of hiv-1 rt by tsao-t was reversible and noncompetitive with respect to dgtp as the substrate and poly(c).oligo(dg) as the template/pri ... | 1992 | 1376314 |
| differential inhibitory effects of tibo derivatives on different strains of simian immunodeficiency virus. | recently, several classes of compounds have been shown to be extremely selective inhibitors of human immunodeficiency virus type 1 (hiv-1) replication in vitro. these include the tetrahydro-imidazo[4,5,1-jk][1,4]-benzodiazepin-2(1h)-one and -thione (tibo), 1-(2-hydroxyethoxymethyl)-6-(phenylthio)-thymine (hept), dipyridodiazepinone, pyridinone and bis(heteroaryl)piperazine derivatives. the hallmark of these new antiviral compounds is a specific interaction with reverse transcriptase (rt) of hiv- ... | 1992 | 1378481 |
| fidelity of the reverse transcriptase of human immunodeficiency virus type 2. | the relatively low fidelity of human immunodeficiency virus type 1 reverse transcriptase (hiv-1 rt) was implicated as a major factor that contributes to the genetic variability of the virus. extension of mismatched 3' termini of the primer dna was shown to be a major determinant of the infidelity of hiv-1 rt. human immunodeficiency virus type 2 (hiv-2) also shows extensive genetic variations. therefore, we have analyzed the fidelity of the dna-dependent dna polymerase activity of hiv-2 rt and co ... | 1992 | 1378791 |
| structure-function relationships of hiv-1 reverse transcriptase determined using monoclonal antibodies. | the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1) is one of the main targets in approaches to the chemotherapy of aids. a detailed knowledge of structure-function relationships of this enzyme is a prerequisite for rational drug design. we have used monoclonal antibodies as tools to identify functionally important regions of the protein. the preparation of 23 murine monoclonal antibodies (mab) against hiv-1 reverse transcriptase and their different effects on the enzym ... | 1992 | 1378837 |
| the calanolides, a novel hiv-inhibitory class of coumarin derivatives from the tropical rainforest tree, calophyllum lanigerum. | eight new coumarin compounds (1-8) were isolated by anti-hiv bioassay-guided fractionation of an extract of calophyllum lanigerum. the structures of calanolide a (1), 12-acetoxycalanolide a (2), 12-methoxycalanolide a (3), calanolide b (4), 12-methoxycalanolide b (5), calanolide c (6) and related derivatives 7 and 8 were solved by extensive spectroscopic analyses, particularly hmqc, hmbc, and difference noe nmr experiments. the absolute stereochemistry of calanolide a (1) and calanolide b (4) wa ... | 1992 | 1379639 |
| detection of a human intracisternal retroviral particle associated with cd4+ t-cell deficiency. | a number of non-human-immunodeficiency-virus (hiv) type 1 disorders are associated with cd4+ t-cell deficiency and dysfunction. however, the etiopathogenesis of cd4+ t-cell immunodeficiency in these disease states remains unclear. human intracisternal retroviral (hicrv) particles were detected in a lymphoblastoid cell line exposed to mononuclear cells from a patient with severe cd4+ t-cell deficiency without risk factors for hiv infection. ultrastructurally, the hicrv is distinct from hiv-1, hiv ... | 1992 | 1380169 |
| (-)-2'-deoxy-3'-thiacytidine is a potent, highly selective inhibitor of human immunodeficiency virus type 1 and type 2 replication in vitro. | the (-)-enantiomer of 2'-deoxy-3'-thiacytidine (3tc) was found to be a potent and selective inhibitor of human immunodeficiency virus types 1 (hiv-1) and 2 (hiv-2) in vitro. we determined its antiviral activity against a number of laboratory strains of hiv-1 and hiv-2 in a range of cd4-bearing lymphocyte cell lines (mean 50% inhibitory concentration [ic50] range, 4 nm to 0.67 microm). 3tc was also active against a range of hiv-1 strains in peripheral blood lymphocytes (mean ic50 range, 2.5 to 90 ... | 1992 | 1380229 |
| identification of a neutralizing domain in the external envelope glycoprotein of simian immunodeficiency virus. | two murine monoclonal antibodies (mabs), designated matg2014 and matg2033, were generated. they are reactive with the external envelope glycoprotein gp130 of the simian immunodeficiency virus of macaque monkey (sivmac251), and display a cell-free virus neutralizing activity in vitro. in addition, matg2014 cross-reacts with hiv-2rod gp140. epitope mapping of these mabs was performed by screening and sivmac peptide library expressed in yeast and confirmed using synthetic peptides. matg2014 and mat ... | 1992 | 1380263 |
| identification of the human immunodeficiency virus reverse transcriptase residues that contribute to the activity of diverse nonnucleoside inhibitors. | the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1) is potently inhibited by a structurally diverse group of nonnucleoside compounds. these include pyridinone derivatives, tetrahydroimadazo[4,5,1-j,k][1,4]-benzodiazepin-2(1h)-one and -thione, and bi-rg-587 (nevirapine). the compounds act noncompetitively, by an unknown mechanism, with respect to template-primer and nucleotide substrates. despite a high degree of similarity between the hiv-1 and hiv-2 rts, the hiv-2 enzy ... | 1992 | 1380789 |
| inhibition of human immunodeficiency virus and growth of infected t cells by the immunosuppressive drugs cyclosporin a and fk 506. | the effects of the immunosuppressive drugs cyclosporin a and fk 506 were studied on cells chronically infected with human immunodeficiency virus type 1 (hiv-1) as well as on uninfected and newly infected cells. when cells chronically infected with hiv-1 or with hiv-2 were cocultivated with uninfected cells in the presence of cyclosporin a or fk 506 there was a delay in the formation of syncytia and of cytopathic effects. this inhibitory effect was not due to decreased membrane expression of cd4. ... | 1992 | 1381509 |
| human and murine monoclonal antibodies directed against a conserved sequence from gp41 (aa583-599) of human immunodeficiency virus type 1. | human spleen cells from an hiv-seropositive donor were immunized in vitro with the aa583-599 peptide conjugated to an heptalysyl core. this sequence was derived from the putatively hiv-immunosuppressive region of hiv1 gp41. the same conjugated peptide was used to immunize mice. one human and one mouse igm monoclonal antibody (mab) directed against the aa583-599 peptide were obtained. the two mab had distinct patterns of reactivity against a panel of 42 peptides with modified sequences. neither o ... | 1992 | 1381515 |
| functional analysis of novel selective mutants of the reverse transcriptase of human immunodeficiency virus type 1. | we have generated by site-directed mutagenesis plasmids that induce the synthesis of specific mutants of the reverse transcriptase (rt) of human immunodeficiency virus type 1 (hiv-1). these recombinant mutants of hiv-1 rt, designed on the basis of our previous studies of hiv-1 and hiv-2 rts, were analyzed for structure-function relationship by assessing their rna-dependent and dna-dependent dna polymerase as well as the ribonuclease h activities. three groups of mutants were studied. 1) we have ... | 1992 | 1382052 |
| subtyping of human immunodeficiency virus isolates with a panel of monoclonal antibodies: identification of conserved and divergent epitopes on p17 and p25 core proteins. | we have investigated the feasibility and significance of subtyping of human immunodeficiency virus (hiv) isolates with monoclonal antibodies (mab) raised against the core proteins of hiv. a panel of 37 mab tested for reactivity with hiv1 oligopeptides was used to analyse the antigenic relatedness among 14 hiv isolates which included 12 isolates of hiv1 from different geographical origins and 2 isolates of hiv2. three out of these 37 mab reacted with conserved epitopes expressed by all 14 hiv iso ... | 1992 | 1382219 |
| fidelity of the rna-dependent dna synthesis exhibited by the reverse transcriptases of human immunodeficiency virus types 1 and 2 and of murine leukemia virus: mispair extension frequencies. | human immunodeficiency viruses type 1 and 2 (hiv-1 and hiv-2, respectively) exhibit extensive genetic variations. it was postulated that much of this genetic variability stems from the low fidelity of the reverse transcription step. both hiv reverse transcriptases (rts) were shown to be particularly error-prone during the in vitro dna-dependent dna synthesis relative to other retroviral rts. extension of mismatched 3'-termini of the primer dna was shown to be a major determinant in the infidelit ... | 1992 | 1382590 |
| identification of a gag protein epitope conserved among all four groups of primate immunodeficiency viruses by using monoclonal antibodies. | five monoclonal antibodies (mabs) were raised against the gag proteins of simian immunodeficiency virus (siv) from african green monkey (sivagmtyo-7). two mabs reacted with the matrix protein p17 and the other three with the core protein p24. studies on the cross-reactivity of the mabs revealed that the anti-p24 mabs detected an epitope shared by the viruses belonging to the human immunodeficiency virus type 2 (hiv-2)/sivmac group and sivagmtyo-7 and sivagmtyo-5. the anti-p17 mabs recognized an ... | 1992 | 1383399 |
| transient stimulation of granulopoiesis and drastic inhibition of erythropoiesis in hiv-2-infected long-term liquid bone marrow cultures. | impaired hematopoiesis is commonly associated with human immunodeficiency virus hiv-1 and hiv-2-related aids. hiv-1 infection of hematopoietic progenitors has been studied, whereas hiv-2 infection of these cells is less well documented. in this work, we studied myeloid and erythroid progenitor production and differentiation in long-term bone marrow (ltbm) cultures after hiv-2 infection. a nonadherent fraction from these cultures containing the hematopoietic progenitors is nonproductively infecte ... | 1992 | 1383491 |
| anti-human immunodeficiency virus activity of a novel synthetic peptide, t22 ([tyr-5,12, lys-7]polyphemusin ii): a possible inhibitor of virus-cell fusion. | more than 40 peptides associated with tachyplesin and polyphemusin, which are highly abundant in hemocyte debris of the horseshoe crabs tachypleus tridentatus and limulus polyphemus, were synthesized. among these peptides, we found that a novel compound, which was called t22 ([tyr-5,12, lys-7]polyphemusin ii), strongly inhibited the human immunodeficiency virus type 1 (hiv-1)-induced cytopathic effect and viral antigen expression. its 50% effective concentration was 0.008 micrograms/ml, while it ... | 1992 | 1384424 |
| sulfonic acid polymers as a new class of human immunodeficiency virus inhibitors. | four sulfonic acid polymers [poly(4-styrenesulfonic acid)(pss), poly(anetholesulfonic acid)(pas), poly(vinylsulfonic acid)(pvs), poly(2-acrylamido-2-methyl-1-propanesulfonic acid)(pamps)] have been found to inhibit the cytopathicity of hiv-1 and hiv-2 in mt-4 cells at concentrations that are not toxic to the host cells. the sulfonic acid polymers also inhibited syncytium formation in co-cultures of molt-4 cells with hiv-1- or hiv-2-infected hut-78 cells. they also inhibited binding of anti-gp120 ... | 1992 | 1384428 |
| [study of the antigenic structure of human immunodeficiency virus using synthetic peptides]. | in a search for synthetic peptide antigens fit to detect anti-hiv antibodies, a set of algorithms were used to predict the probable antigenic determinants of gag, pol, env and nef proteins of hiv-1 and hiv-2. over forty peptides were synthesized by the solid-phase method. the reactivity of the peptide antigens was evaluated in elisa on panels of hiv-1/2-positive sera. application of the synthetic peptides for the early hiv diagnostics was examined. | 1992 | 1384509 |
| inhibition of human immunodeficiency virus infection in human colon epithelial cells by recombinant interferon-gamma. | pretreatment of human colon epithelial cells ht29 by recombinant gamma interferon (ifn)-gamma was found to protect the cells from infection with various isolates of human immunodeficiency virus (hiv)-1 and hiv-2, as assessed by co-cultivation with human t lymphoblastoid cells and gene amplification by polymerase chain reaction technique. additionally, ifn-gamma induced a dose-dependent inhibition of hiv-1 and hiv-2 production in chronically infected ht29 cells. in situ hybridization studies demo ... | 1992 | 1396956 |
| discovery and characterization of an hiv-1 tat antagonist. | ro 5-3335, 7-chloro-5-(2-pyrryl)-3h-1,4-benzo-diazepin-2-(h)-one, has been shown to inhibit gene expression controlled by the human immunodeficiency virus-1 (hiv-1) ltr promoter. the inhibition was specific for the viral transcriptional transactivator tat. the compound did not inhibit the basal activity of the hiv-1 ltr or the activity of promoters not responsive to tat. consistent with its mode of action, ro 5-3335 inhibited hiv-1 replication (ic50 = 0.1-1 microm) by reducing viral rna synthesi ... | 1992 | 1397654 |
| activity and dimerization of human immunodeficiency virus protease as a function of solvent composition and enzyme concentration. | the activity of human immunodeficiency virus 1 (hiv-1) protease has been examined as a function of solvent composition, incubation time, and enzyme concentration at 37 degrees c in the ph 4.5-5.5 range. glycerol and dimethyl sulfoxide inhibit the enzyme, while polyethylene glycol and bovine serum albumin activate the enzyme. when incubated at a concentration of 50-200 nm, the activity of the protease decreases irreversibly with an apparent first-order rate constant of 4-9 x 10(-3) min-1. the pre ... | 1992 | 1400318 |
| hiv-2 infections in a rural senegalese community. | in a community study in rural senegal, 22 human immunodeficiency virus type-2 (hiv-2) seropositive cases and 64 matched controls were examined clinically and evaluated immunologically. the presence of clinical signs was highly correlated with hiv-2 seropositivity: 9 anti-hiv-2 positive patients and 5 controls presented with clinical signs (odd ratio [or] = 8.2, confidence limits [cl] 2-35). the main symptom associated with hiv-2 seropositivity was a chronic cough (or = 18.5, cl 1.8-899). the pre ... | 1992 | 1402831 |
| arteriopathy in macaques infected with simian immunodeficiency virus. | an arteriopathy characterized by intimal and medial thickening and fibrosis was seen in 19 of 85 rhesus monkeys infected with simian immunodeficiency virus (siv), a lentivirus with morphologic, genetic, and biologic similarities to hiv-1 and hiv-2. | 1992 | 1405492 |
| mutational analysis of the integrase protein of human immunodeficiency virus type 2. | purified integrase protein (in) can nick linear viral dna at a specific site near the ends and integrate nicked viral dna into target dna. we have made a series of 43 site-directed point mutants of human immunodeficiency virus type 2 in and assayed purified mutant proteins for the following activities: site-specific cleavage of viral dna (donor cut), integration (strand transfer), and disintegration. in general, the different activities were similarly affected by the mutations. we found three mu ... | 1992 | 1409671 |
| lignified materials as medicinal resources. v. anti-hiv (human immunodeficiency virus) activity of some synthetic lignins. | a class of synthetic lignins (dehydrogenation polymers of p-coumaric acid, ferulic acid, and caffeic acid) inhibited cytopathogenicity of hiv-1 and hiv-2 infection. the ratio of cytotoxic to anti-hiv (human immunodeficiency virus) doses depended strongly on conditions during polymer preparation. the activity increased when polymers were treated with reducing agent nabh4, whereas it decreased when treated with oxidizing agent ceric ammonium nitrate. the polymers inhibited expression of hiv-specif ... | 1992 | 1423763 |
| worldwide survey of aids vaccine challenge studies in nonhuman primates: vaccines associated with active and passive immune protection from live virus challenge. | an aids vaccine surveillance system (avss) was designed and implemented to track the rapidly growing international database supporting the development of promising aids vaccines. both preclinical nonhuman primate (nhp) and clinical human trials are tracked by the avss. this report presents summary data generated from the avss on the nhp aids vaccine/live virus challenge studies only. summary data on more than 100 preclinical hiv/siv vaccines are presented within the framework of 1) 13 arbitrary ... | 1992 | 1433265 |
| sulfation of the human immunodeficiency virus envelope glycoprotein. | sulfation is a posttranslational modification of proteins which occurs on either the tyrosine residues or the carbohydrate moieties of some glycoproteins. in the case of secretory proteins, sulfation has been hypothesized to act as a signal for export from the cell. we have shown that the human immunodeficiency virus type 1 (hiv-1) envelope glycoprotein precursor (gp160) as well as the surface (gp120) and transmembrane (gp41) subunits can be specifically labelled with 35so42-. sulfated hiv-1 env ... | 1992 | 1433500 |
| chimeric gag-v3 virus-like particles of human immunodeficiency virus induce virus-neutralizing antibodies. | a 41-kda unprocessed human immunodeficiency virus 2 (hiv-2) gag precursor protein that has a deletion of a portion of the viral protease assembles as virus-like particles by budding through the cytoplasmic membrane of recombinant baculovirus-infected insect cells. we have constructed six different combinations of chimeric genes by coupling the truncated hiv-2 gag gene to the neutralizing domain (v3) or the neutralizing and the cd4 binding domains (v3+cd4bd) of gp120 env gene sequences from hiv-1 ... | 1992 | 1438241 |