Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inactivation of a range of viruses, such as adeno-, mumps, rota-, polio- (types 1 and 3), coxsackie-, rhino-, herpes simplex, rubella, measles, influenza and human immunodeficiency viruses, by povidone-iodine (PVP-I) and other commercially available antiseptics in Japan was studied in accordance with the standardized protocol in vitro. In these experiments, antiseptics such as PVP-I solution, PVP-I gargle, PVP-I cream, chlorhexidine gluconate, alkyldiaminoethyl-glycine hydrochloride, benzalkonium chloride (BAC) and benzethonium chloride (BEC) were used. PVP-I was effective against all the virus species tested. PVP-I drug products, which were examined in these experiments, inactivated all the viruses within a short period of time. Rubella, measles, mumps viruses and HIV were sensitive to all of the antiseptics, and rotavirus was inactivated by BAC and BEC, while adeno-, polio- and rhinoviruses did not respond to the other antiseptics. PVP-I had a wider virucidal spectrum, covering both enveloped and nonenveloped viruses, than the other commercially available antiseptics.
 ...
PMID:Inactivation of human viruses by povidone-iodine in comparison with other antiseptics. 940 52

Intestinal mucosa represents an important portal of entry of HIV and a site of virus reservoir and active replication. Recently, in HIV patients, an early depletion of intestinal lamina propria T lymphocytes (LPT) has been described. HIV-1 gp120 has been demonstrated to promote apoptosis in noninfected isolated peripheral blood T cells, therefore we investigated whether gpl20 modulates apoptosis of normal human intestinal lamina propria T cells. Purified T cells were obtained by immunomagnetic negative selection from human lamina propria mononuclear cells isolated from surgical specimens by enzymatic procedure. Cells were incubated with or without recombinant gpl20 (10 microg/ml) and cultured either in the absence of any stimulus or in the presence of plate-bound anti-CD3 Ab (OKT3) or soluble anti-CD2 Ab (T11(2) + T11[3]). Apoptosis was assessed by flow cytometric analysis after propidium iodide staining. We demonstrated that preincubation of normal LPT cells with HIV-1 gpl20 accelerates the apoptosis observed during CD2-pathway stimulation of LPT cells. This process is mediated by Fas/Fas ligand interaction and related to an increased induction of Fas ligand mRNA by gpl20. Therefore HIV-1 gp120 could contribute to the depletion of noninfected LPT cells inducing a premature cell death.
 ...
PMID:HIV-1 gp120 accelerates Fas-mediated activation-induced human lamina propria T cell apoptosis. 947 52

Isolated immune complexes from sera of 49 out of 67 human immunodeficiency virus-1-positive (HIV-1+) patients (CIC-HIV+), composed of anti-HIV-HIV-Ag, could induce apoptosis on normal phytohaemagglutinin (PHA)-activated lymphocytes. DNA degradation was detected by propidium iodide staining. This activity is directed against CD4+ lymphocytes as demonstrated by double binding of CIC-HIV+ and anti-CD4 on apoptosis cells. Expression of Fas antigen is prior to apoptotic phenomena. CIC-HIV+ apoptosis inducers belong mainly to asymptomatic HIV-infected patients, indicating that immune complexes from these patients can destroy CD4+ lymphocytes.
 ...
PMID:Circulating immune complexes from HIV-1+ patients induces apoptosis on normal lymphocytes. 948 2

Mixtures of a good hydrogen bond donor, 2,2,2-trifluoroethanol (TFE) or 1,1,1,3,3,3-hexafluroisopropanol, and an acceptor, dimethylformamide (DMF) (1:1, v/v), containing 4% buffer have been described as adequate solvent systems for trypsin-catalyzed peptide fragment condensations [Mihara et al. (1993) Int. J. Pept. Protein Res. 41, 405]. Thus, we decided to study the behaviour of trypsin in such solvent systems. We investigated whether this protease would efficiently catalyze condensations between fragments derived from an analogue of the gp-41 capsid protein of HIV virus or from cholecystokinin-22. None of the reactions carried out yielded the desired condensation products. However, when Fmoc-NLQNLDPSHR-OH and cholecystokinin-12 (H-ISDRDYMGWMDF-NH2) were used as substrates, the last had its R-D peptide bond hydrolyzed producing cholecystokinin-8. The proteolytic activity of this enzyme measured against a fluorogenic peptide derivative was 50 times lower in DMF/TFE containing 5% of aqueous phase than in buffer. Steady-state fluorescence studies in DMF/TFE buffer were performed to examine the structure of this protease in these media. Steady-state spectra obtained with increasing proportions of these two organic solvents in buffer showed that the emission intensities built up. Quenching studies with iodide revealed that the Io/I ratio (where Io and I are the fluorescence emission intensities in the absence and presence of quencher, respectively) changed from 1.2 in aqueous media to 2.2 in DMF/TFE (1:1, v/v) containing 11% 0.2 M Tris-HCl buffer, pH 8.0, for 0.5 M iodide. The complete data indicated a higher exposure of tryptophan residues to the quencher in organic media, probably because of the partial unfolding of the enzyme.
 ...
PMID:Mixtures of trifluoroethanol or hexafluoroisopropanol and dimethylformamide are not of general applicability for peptide condensations catalyzed by trypsin. 949 88

It has been reported previously that cells expressing a truncated form of CD4 which lacks the cytoplasmic tail of the molecule (truncation at position 402) were not sensitive to human immunodeficiency virus type 1 (HIV-1)-induced apoptosis in an acute-phase model of infection (J. Corbeil, M. Tremblay, and D. D. Richman, J. Exp. Med. 183:39-48, 1996). The role played by the cytoplasmic domain of CD4 in HIV-1-induced apoptosis was reexamined here with clones of A2.01 cells expressing different forms of CD4 and the DNA intercalant YOPRO-1 assay. Six days after virus exposure, we found evidence of apoptosis in A2.01 cells expressing the wild-type CD4 (A2.01/CD4), whereas enhanced apoptosis remained absent in cultures of A2.01/CD4.401 and A2.01/CD4.403 cells (A2.01 cells which express CD4.401 and CD4.403 molecules with truncations at positions 401 and 403, respectively). However, cell death by apoptosis measured with YOPRO-1 was found in cultures of A2.01/CD4.401 and A2.01/CD4.403 cells 15 days after virus exposure. This result was confirmed with a terminal dUTP nick end-labeling assay and propidium iodide staining. The long lag time postinfection required for apoptosis to be observed in cultures of infected cells expressing truncated forms of CD4 was due to the delayed viral replication in these cells, as shown by monitoring of the viral reverse transcriptase activity and HIV-1 p24gag antigen expression. These results emphasize the relationship between virus replication and cell death by apoptosis.
 ...
PMID:Delayed human immunodeficiency virus type 1-induced apoptosis in cells expressing truncated forms of CD4. 949 24

Recombinant soluble human CD4 (rsCD4) has been used in iodinated form to study the interaction of CD4 with its ligands. However, the utility of [125I]-rsCD4 is limited because rsCD4 is inefficiently iodinated and the iodinated protein is poorly active. The iodination properties of rsCD4 most likely reflect the poor accessibility of the tyrosine residues, apparent from the available X-ray structures. We have generated an iodinatable mutant of rsCD4 by substituting Tyr for Phe(179) in the flexible, solvent-exposed C-terminal region of rsCD4(183), a truncated form of CD4 that consists of the first 183 residues of CD4 and includes the binding sites for HIV-1 gp120 and MHC class II molecules. When F179Y rsCD4(183) is iodinated under trace-labeling conditions, the efficiency of 125I incorporation and the percentage of iodinated molecules that are active are much enhanced compared with WT rsCD4. Moreover, trace-labeled [125I]-F179Y rsCD4(183) has the same affinity for HIV-1 rgp120 as unlabeled WT rsCD4. The improved activity of trace-labeled [125I]-F179Y rsCD4(183) appears to be due to effective competition by Y179 for reactive iodine species that, in WT rsCD4, react with traces of denatured protein and/or with residues critical for activity or conformational integrity. The incorporation of accessible tyrosine residues may improve the iodinatibility of a protein both by introducing a readily iodinatable residue and by protecting sensitive proteins from adverse reactions.
 ...
PMID:Construction and characterization of a radio-iodinatable mutant of recombinant human CD4. 952 Mar 4

The small HIV-1 accessory protein Vpr (virus protein R) is a multifunctional protein that is present in the serum and cerebrospinal fluid of AIDS patients. We previously showed that Vpr can form cation-selective ion channels across planar lipid bilayers, introducing the possibility that, if incorporated into the membranes of living cells, Vpr might form ion channels and consequently perturb the maintained ionic gradient. In this study, we demonstrate, by a variety of approaches, that Vpr added extracellularly to intact cells does indeed form ion channels. We use confocal laser scanning microscopy to examine the subcellular localization of fluorescently labeled Vpr. Plasmalemma depolarization and damage are examined using the anionic potential-sensitive dye bis(1,3-dibutylbarbituric acid) trimethine oxonol and propidium iodide (PI), respectively, and the effect of Vpr on whole-cell current is demonstrated directly by using the patch-clamp technique. We show that recombinant purified extracellular Vpr associates with the plasmalemma of hippocampal neurons to cause a large inward cation current and depolarization of the plasmalemma, eventually resulting in cell death. Thus, we demonstrate a physiological action of extracellular Vpr and present its mechanistic basis. These findings may have important implications for neuropathologies in AIDS patients who possess significant amounts of Vpr in the cerebrospinal fluid.
 ...
PMID:Extracellular HIV-1 virus protein R causes a large inward current and cell death in cultured hippocampal neurons: implications for AIDS pathology. 953 83

Various 2,3-dideoxy-2,2-difluoro-L-glycero-pentofuranosyl nucleosides were synthesized via the key intermediate, 5-O-benzoyl-2,3-dideoxy-2,2-difluoro-L-glycero-pentofuranose (6). 2,3-O-Isopropylidene-L-glyceraldehyde was coupled with ethyl bromodifluoroacetate under Reformatsky conditions to obtain the diastereomeric mixture of ethyl (4S)-3-hydroxy-3-(2,2-dimethyl-1,3-dioxolan-4-yl)-2,2-difluoro propionate (1). Treatment of compound 1 with carbon disulfide, sodium hydride and methyl iodide followed by reduction afforded ethyl (4S)-3-(2,2-dimethyl-1,3-dioxolan-4-yl)-2,2-difluoro propionate (3). Compound 3 was treated with 5% HCl in ethanol, followed by refluxing in benzene under Dean-Stark conditions, to afford the lactone 4. The compound 4 was protected and reduced to afford the key intermediate 6. For the synthesis of pyrimidine derivatives 8-21, compound 6 was converted to the mesylate 7 and condensed with various silyl protected pyrimidine bases. The inosine and adenine derivatives 38-41 were obtained from compound 6 and 6-chloropurine using standard procedures. Compounds 22-35 and 38-41 were evaluated for their antiviral activity against HIV-1, HBV, HSV-1 and HSV-2, and for cellular toxicity. None of the synthesized compounds showed any significant activity or toxicity. Single-crystal X-ray structure of 1-(2,3-dideoxy-2,2-difluoro-beta-L-glycero-pentofuranosyl)-5-iodocytosin e (34) suggested a 2'-exo/3'-endo conformation for the carbohydrate moiety.
 ...
PMID:Synthesis of 2,3-dideoxy-2,2-difluoro-L-glycero-pentofuranosyl nucleosides. 969 40

Economic deterioration and a decade of military rule have had a disastrous impact on the health of women and children in Burma. In 1996, Burma's infant mortality rate was 105/1000 live births. The major causes of child mortality and morbidity are intestinal and respiratory infections, malaria, malnutrition, and vaccine-preventable diseases. Low birth weight, iodine and vitamin A deficiency diseases, and iron-deficiency anemia are widespread. Cholera outbreaks occur each year. The Universal Child Immunization Program, supported by UNICEF, reaches less than 60% of eligible children. The maternal mortality rate is 580/100,000 live births; most are related to unsafe abortion. Basic reproductive health care is available only in select areas of the country. 17-22% of women use modern contraception. UNAIDS has estimated that 440,000 Burmese are HIV-infected and there are 14,000 AIDS orphans. HIV prevalence is 26.5% in urban prostitutes, 91% among injecting drug users near the Chinese border, and 10.6% among pregnant women in one border town. Any improvement in the health status of the population requires a shift in priority on the part of the military government from weapons build-up to health promotion and protection.
 ...
PMID:Burma: a country's health in crisis. 977 77

The aim of this study was to estimate thyroid function and the prevalence of thyroid antibodies among HCV seropositive patients. We undertook a screening for thyroid dysfunction, and antithyroperoxidase (ATPO) and antithyroglobulin (ATG) antibodies, in 215 HCV seropositive patients referred for hepatologic consultation, 118 males and 97 females, mean age 44 +/- 14 years, range 16-80 years. No patient was treated with interferon and all were seronegative for HIV. Eighteen patients (8%) had antithyroid antibodies, 12 with ATPO antibodies (5.6%) and 10 with ATG antibodies (4.7%). Four patients had both ATPO and ATG antibodies (1.8%), one case of Graves' disease and 3 cases of autoimmune hypothyroidism found during this study. Five patients (2.3%) had hyperthyroidism, three cases of Graves' disease, one case of iodine load and a case of Grave's disease incidentally diagnosed during medical examination. Eleven patients (5.1%) had hypothyroidism, one case already known and treated without antithyroid antibodies, 4 cases of autoimmune etiology (3 diagnosed in consultation and one already known and compensated hypothyroidism), one case of amiodarone-induced hypothyroidism discovered during this study, 5 cases of hypothyroidism without antibodies (two cases of compensated hypothyroidism with normal TRH stimulating test, two cases with severe liver cirrhosis and one case with chronic hepatitis). Twelve patients had antithyroid antibodies with normal TSH levels. The prevalence of ATPO and ATG antibodies in our study is similar to the prevalence usually observed in general population and does not suggest a pathogenic role of HCV in autoimmune thyroid disorders.
 ...
PMID:[Thyroid function and autoimmunity in 215 patients seropositive for the hepatitis C virus]. 975 92


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>