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

An increase in serum lactate dehydrogenase (LDH) activity is commonly taken to support the presumptive diagnosis of Pneumocystis carinii pneumonia (PCP), although the LDH level may also be increased in other lung infections and in a variety of extrapulmonary disorders. To assess its diagnostic value in patients with fever, lung infiltrates, and a high prevalence of HIV infection, we compared LDH levels in 42 hospitalized patients with PCP, 71 with disseminated tuberculosis (TB), 40 with pulmonary TB, and 37 with bacterial pneumonia. Peak LDH level was higher (p < 0.05) in patients with PCP (547 +/- 157 U/L) and disseminated TB (569 +/- 338 U/L) than in patients with pulmonary TB (258 +/- 66 U/L) or bacterial pneumonia (331 +/- 139 U/L). However, substantial overlap between groups limited its diagnostic value for individual patients. Expressing LDH as its ratio to simultaneous serum aminotransferases (AST or ALT) did not enhance its discriminatory value. Most patients in each group had abnormalities in other serum enzymes (AST, ALT, alkaline phosphatase, gamma-glutamyltransferase), making an isolated elevation of LDH level uncommon (21% of PCP cases). Serum LDH has a high sensitivity for PCP (100% in this series) but must be interpreted with caution given its lack of specificity.
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PMID:Serum lactate dehydrogenase (LDH) in Pneumocystis carinii pneumonia, tuberculosis, and bacterial pneumonia. 763 77

We have used an indirect-capture enzyme-linked immunosorbent assay to quantitate the reactivity of sera from human immunodeficiency virus type 1 (HIV-1)-infected humans with native recombinant gp120 (HIV-1 IIIB or SF-2) or with the gp120 molecule (IIIB or SF-2) denatured by being boiled in the presence of dithiothreitol with or without sodium dodecyl sulfate. Denaturation of IIIB gp120 reduced the titers of sera from randomly selected donors by at least 100-fold, suggesting that the majority of cross-reactive anti-gp120 antibodies present are directed against discontinuous or otherwise conformationally sensitive epitopes. When SF-2 gp120 was used, four of eight serum samples reacted significantly with the denatured protein, albeit with ca. 3- to 50-fold reductions in titer. Only those sera reacting with denatured SF-2 gp120 bound significantly to solid-phase-adsorbed SF-2 V3 loop peptide, and none bound to IIIB V3 loop peptide. Almost all antibody binding to reduced SF-2 gp120 was blocked by preincubation with the SF-2 V3 loop peptide, as was about 50% of the binding to native SF-2 gp120. When sera from a laboratory worker or a chimpanzee infected with IIIB were tested, the pattern of reactivity was reversed, i.e., there was significant binding to reduced IIIB gp120, but not to reduced SF-2 gp120. Binding of these sera to reduced IIIB gp120 was 1 to 10% that to native IIIB gp120 and was substantially decreased by preincubation with IIIB (but not SF-2) V3 loop peptide. To analyze which discontinuous or conformational epitopes were predominant in HIV-1-positive sera, we prebound monoclonal antibodies (MAbs) to IIIB gp120 and then added alkaline phosphatase-labelled HIV-1-positive sera. MAbs (such as 15e) that recognize discontinuous epitopes and compete directly with CD4 reduced HIV-1-positive sera binding by about 50%, whereas neutralizing MAbs to the C4, V2, and V3 domains of gp120 were either not inhibitory or only weakly so. Thus, antibodies to the discontinuous CD4-binding site on gp120 are prevalent in HIV-1-positive sera, antibodies to linear epitopes are less common, most of the antibodies to linear epitopes are directed against the V3 region, and most cross-reactive antibodies are directed against discontinuous epitopes, including regions involved in CD4 binding.
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PMID:Antibodies to discontinuous or conformationally sensitive epitopes on the gp120 glycoprotein of human immunodeficiency virus type 1 are highly prevalent in sera of infected humans. 767 8

A colorimetric assay for reverse transcriptase (RT) of the human immunodeficiency virus type 1 (HIV-1) was developed using a double labelled (biotin and digoxigenin) deoxyuridine triphosphate mixture instead of tritiated thymidine triphosphate. After the RT reaction, the newly polymerized strand from oligodeoxythymidylic acid (oligo-dT) contained both biotin and digoxigenin labels. This nucleotide was bound to streptavidin-magnetic beads by the reaction to biotin. At the detection step, an alkaline phosphatase conjugated antibody to digoxigenin was added, followed by the reaction of a colorimetric substrate for this enzyme. This RT assay was comparable to the isotopic RT assay using purified AMV-RT and two strains of HIV grown in cell lines. In addition it was equivalent to the isotopic RT assay for analysis of the time course of in vitro infection of human peripheral blood lymphocytes by HIV-1. The total assay time after the RT reaction step was less than one hour.
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PMID:Colorimetric reverse transcriptase assay for HIV-1. 767 95

The level of human immunodeficiency virus type 1 (HIV-1) RNA in human plasma has been quantitated directly with use of a solid-phase nucleic acid hybridization assay, based on branched DNA (bDNA) signal amplification technology with chemiluminescent detection. Signal amplification is accomplished by the incorporation of sites for 1,755 alkaline phosphatase-labeled probes per genome of HIV-1, after successive hybridization of target-specific oligonucleotides and bDNA amplifier molecules. The assay is performed in microwells, much like an immunoassay, and is amenable to routine laboratory use. Reproducibility and specificity studies indicated that the bDNA method was precise and showed no reactivity with seronegative donors. HIV-1 RNA levels were quantitated for 348 seropositive specimens, with a detection rate of 83% for those specimens from patients with < 500 CD4+ T-cell counts. Plasma RNA levels were found to change with disease stage, and in response to antiviral therapy. Quantitation of HIV-1 RNA in the plasma of HIV-1-infected patients, with use of the bDNA assay, may be a useful method for monitoring HIV-1 disease progression and therapeutic response.
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PMID:Rapid and precise quantification of HIV-1 RNA in plasma using a branched DNA signal amplification assay. 769 40

In order to elucidate the genetic effects on the growth and development of craniofacial regions, HIV-1 transgenic mice (TG mice) which exhibited the phenotype of anterior crossbites were investigated by various methods. Northern hybridization showed that the introduced gene was expressed from 14.5 days post coitum to adult. In morphological measurements using digital converter "GRADICON", significant differences between TG mice and wild type mice (WT mice) were found at 5 weeks of age (5W) for most measurement items. Especially at 7W, the results indicated remarkable reductions in maxilla and catch up growth in the mandible. On the other hand, the serum alkaline phosphatase activity of TG mice (3W, 5W, and 7W) was significantly higher than that of WT mice, and also the low level of inorganic phosphate was detected at 3W for TG mice. These results suggested that TG mice had a disorder of bone metabolism. Other TG mouse lines carrying the same DNA construct showed normal figures in the craniofacial regions, suggesting the possibility that the phenotype of anterior crossbites and the disorder of bone metabolism were not caused by functions of HIV-1 genome but by insertional mutation in craniofacial development.
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PMID:[Study on transgenic mice growing into craniofacial anomaly]. 775

We report here on the construction and use of a novel human immunodeficiency virus (HIV) type 1 reporter vector, HIV-AP, that encodes human placental alkaline phosphatase. Upon staining with chromogenic alkaline phosphatase substrates 24 to 36 h postinfection, cells infected with HIV-AP develop an intense purple color and can then be counted under a dissecting microscope. Alternatively, HIV-AP infectivity can be quantitated and infected cells can be sorted by a fluorescence-activated cell sorter after staining with a fluorescent alkaline phosphatase substrate. The assay is rapid and accurate, has very low background in a variety of cell lines and primary cells, and is not restricted to use in human cells. Infectious HIV-AP can be pseudotyped by various HIV or murine leukemia virus envelope glycoproteins. Using this virus, we have addressed the long-standing question of CD4-independent infection of cells by HIV. Our results confirm the presence on a human osteosarcoma cell line of an alternative receptor for HIV infection that functions with an efficiency approximately 1/20 that of CD4.
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PMID:Use of a novel human immunodeficiency virus type 1 reporter virus expressing human placental alkaline phosphatase to detect an alternative viral receptor. 776 29

The role of interdigitating dendritic cells (IDCs) in the early pathogenesis of African swine fever (ASF) was investigated using mandibular lymphoid tissue from normal pigs and pigs inoculated oronasally with highly virulent Lisbon 60 (L-60) and moderately virulent Dominican Republic 1979 (DR-2) ASF virus (ASFV) isolates. Paraffin-embedded tissue sections were immunostained for ASFV antigen and S-100 protein, a marker of IDCs, using an avidin-biotin alkaline phosphatase procedure. Swine IDCs were identified morphologically by light microscopy, electron microscopy, and S-100 immunostaining. Infection with ASFV caused a marked reduction in S-100 staining by 3 days postinfection (DPI) that persisted through 14 DPI. Early ASFV infection of IDCs was demonstrated at 3 DPI by double immunohistochemical staining of cryosections and by transmission electron microscopy. These results support the hypothesis that the failure of a humoral immune response to virulent ASFV may be due to a primary infection of IDCs and the inability of IDCs to initiate an immune response. Infection of IDCs has also been demonstrated with human immunodeficiency virus (HIV-1), and these infections have some aspects in common.
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PMID:Early infection of interdigitating dendritic cells in the pig lymph node with African swine fever viruses of high and low virulence: immunohistochemical and ultrastructural studies. 777 60

A previously healthy, now 42-year-old man suddenly fell ill with bouts of septic fever up to 39.5 degrees C, sweats and weight loss without any demonstrable organ involvement. Physical examination on hospitalization 3 weeks after onset of the illness was unremarkable. Blood sedimentation rate at one hour was 123 mm. There was also a moderate increase in gamma-GT and alkaline phosphatase. Routine bacteriological and serological tests failed to discover a causative microorganism. After imaging tests had provided first indication of splenic and hepatic involvement, biopsies of these two organs demonstrated disseminated epithelioid granulomas and Langhans giant cells. Staining and culturing of pelvic crest biopsy tissue showed evidence of Mycobacterium tuberculosis, but there was no evidence of pulmonary involvement. In addition to four-drug tuberculostatic treatment the patient was given glucocorticoids for several weeks to control the fever bouts. Persistent CD4+ T-lymphocytopenia was demonstrated as the cause of the entirely extrapulmonary tuberculosis in this HIV-negative patient. This is an only recently described and so far unexplained syndrome.
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PMID:[Disseminated extrapulmonary tuberculosis in idiopathic CD4-lymphocytopenia]. 782 Dec

2',3'-didehydro-2',3'-dideoxythymidine (D4T) is a thymidine analogue with potent anti-HIV activity in vitro and is currently being investigated therapeutically in patients with advanced HIV infection. We describe a first one-step competitive ELISA method developed for D4T measurement. Anti-D4T rabbit antibodies were raised against a D4T hemisuccinate-bovine serum albumin immunogen. A D4T-hemisuccinate-horseradish peroxidase conjugate and a monoclonal anti-rabbit IgG antibody insolubilized onto a microtiter plate were used as a tracer and capture system, respectively. The method was capable of detecting 2 ng/ml of D4T in cell cultures and 20 ng/ml of D4T in plasma samples previously separated in microconcentrator devices. Cross-reactivity analysis showed that thymidine, D4T monophosphate, or azidothymidine, were weakly recognized by the ELISA and that thymine or other nucleosides were unreactive. The test was successfully used for the quantification of D4T in cell extracts from CEM or Molt 4 cell lines cultured with D4T and in the plasma of patients with advanced HIV infection, receiving D4T therapy. Moreover this ELISA could be used for the indirect quantification of D4T phosphorylated intracellular metabolites previously separated by reverse phase HPLC and hydrolyzed with alkaline phosphatase.
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PMID:Measurement of the anti-HIV agent 2',3'-didehydro-2',3'-dideoxythymidine (D4T) by competitive ELISA. 796 88

We have developed a new non-isotopic polymerase chain reaction (PCR) based method for the detection of the human immunodeficiency virus type 1 (HIV-1) DNA in clinical samples. In this method a two step PCR is used to amplify and label HIV-1 DNA segments by incorporation of digoxigenin-11-dUTP (dig-dUTP). Digoxigenin labelled amplified products are hybridized to membrane immobilized complementary DNA probes. Hybridization is detected non-radioactively by incubating the filters with antidigoxigenin antibody conjugated with alkaline phosphatase followed by a standard phosphatase assay. With this method the detection limit was between 1 and 10 HIV-1 DNA copies in a background of 1 microgram of human genomic DNA. Furthermore, we were able to detect HIV-1 DNA in 41 out of 41 HIV-1 antibody positive individuals while 10 out of 10 HIV-1 seronegative individuals gave consistently negative results. Our data indicate that this simple non-isotopic technique is sensitive and specific for the detection of HIV-1 DNA in clinical samples and can constitute a good alternative to other non-isotopic methods described to date.
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PMID:Detection of HIV-1 DNA by polymerase chain reaction incorporation of digoxigenin-11-dUTP and hybridization to immobilized probes. 796 98


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