Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of human immunodeficiency virus (HIV) coinfection and hepatitis C virus (HCV) genotype distribution on HCV viral load and alanine amino transferase (ALT) levels in chronically infected patients remains unclear. In the present study, serum samples from a group of haemophiliac patients were investigated retrospectively. HCV geno- and subtyping was carried out using the Inno line probe assay (Inno LIPA, Innogenetics, Zwijnaarde, Belgium) in 87 patients positive by HCV RT PCR. Of these patients, 31 (35.6%) were HIV coinfected. HCV RNA was quantified with the HCV Monitor kit (Roche, Basel, Switzerland) in 43 patients (22 HIV-negatives, 21 HIV-positives). The most prevalent genotypes were 1 (n = 52) and 3a (n = 16) followed by genotype 2 (n = 9) and 4 (n = 3). Mixed infections were detected in 7 patients. Of genotype 1 positive samples, 24 and 23 were classified as subtype a and b, respectively. Five samples could not be subtyped. Although higher mean values of ALT were observed in genotype 1 infected patients, there was no statistically significant association between HCV genotype or subtype and liver enzymes (P > 0.05). On the other hand, statistically significant higher HCV RNA titres were observed in haemophiliacs infected with HCV genotype 1 in comparison to those infected with other genotypes (P < 0.01). No relationship was found between the presence of HIV coinfection and viral load of HCV RNA. There was no evidence that HCV infection had a more severe outcome in HIV-positive patients who had been infected with HIV and HCV more than ten years ago, even in those with very low CD4+ cell counts. No clear association between high ALT levels and large amounts of viral RNA was observed. In conclusion, a large viral load is associated with HCV genotype 1 infection; HIV coinfection has no clear effect on the intensity of HCV replication. An ongoing prospective study will evaluate the respective role of viral load, genotype, HIV coinfection and ALT level in the response to interferon therapy.
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PMID:Hepatitis C plasma viral load is associated with HCV genotype but not with HIV coinfection. 869 66

We developed a simple, inexpensive, rapid assay for the detection of antibodies to simian immunodeficiency virus (SIV) and human immunodeficiency virus type 1 (HIV-1) in serum. The immunoassay uses inactivated SIV and HIV-1 gp41 transmembrane recombinant protein as antigenic adsorbents on a nitrocellulose filter membrane. Diluted serum, with the addition of Protein-A-Gold, is gravity-filtered through the filter membrane, blocked, and buffer-washed. Antibodies to HIV or SIV or both in serum bind to the appropriate antigen, and the resulting antigen-antibody complex reacts with Protein-A-Gold to produce a readable pink color. Field evaluation of the test on 30 human and 70 nonhuman primate sera in Kenya and Zaire indicated that the test had at least 93 and 90% correlation with Western blot sensitivity and specificity respectively. Prior refrigeration of the test kit and incubation of sera during testing were not required. This result indicates that the test may be a rapid, economical, and simple test for detecting HIV, SIV, or both in serum. This immunoassay can be useful for carrying out HIV and SIV serosurveys in countries with limited or no laboratory facilities.
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PMID:Immunoassay for detection of antibodies to simian immunodeficiency virus and human immunodeficiency virus in serum. 872 37

Zidovudine (ZDV, AZT) is the first clinically effective drug licensed for use in the treatment of human immunodeficiency virus (HIV) infection. Activation of ZDV requires phosphorylation to ZDV triphosphate by cellular kinases. It is important, therefore, to determine the intracellular levels of the active form because measurement of ZDV concentrations in plasma have not reflected any direct relationship with activity or toxicity. In this paper a validated assay for the measurement of both ZDV and its three phosphorylated anabolites, ZDV mono-, di- and triphosphate, in peripheral blood mononuclear cells (PBMCs) is described. The method consisted of a combination of isocratic high performance liquid chromatography (HPLC) separation and radioimmunoassay (RIA). The PBMCs were separated from whole blood and ZDV and ZDV nucleotides were extracted and separated by isocratic elution with an ion-pairing mobile phase on a reversed-phase HPLC column. The collected ZDV and individual ZDV nucleotide fractions were dephosphorylated to ZDV, cleaned by solid phase extraction and assayed by a commercially available RIA kit. The assay developed was successfully used to determine intracellular ZDV and anabolite concentrations of 10 PBMC samples taken from HIV positive patients on ZDV treatment.
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PMID:Quantification of zidovudine and individual zidovudine phosphates in peripheral blood mononuclear cells by a combined isocratic high performance liquid chromatography radioimmunoassay method. 872 49

Early diagnosis of infection with human immunodeficiency virus type 1 (HIV- 1) in young infants is essential to decisions on their medical and social care. Whereas studies have suggested that polymerase chain reaction (PCR) is a sensitive and timely method of diagnosing HIV infection in children, these evaluations have been limited by the number of specimens studied. Recently, Roche Molecular Systems developed a complete HIV-1 DNA PCR testing kit (from specimen preparation to detection). In this study, use of this PCR test kit was evaluated for the detection of HIV infection in infants of seropositive mothers who were enrolled in the longitudinal, multicenter Women and Infants' Transmission Study. A total of 1209 blood specimens from 483 infants were tested and analyzed. The overall sensitivity and specificity of a single PCR test in determining HIV infection status in infants more than 1 but less than 36 months of age were 95% and 97%, respectively. For infected infants 1 to 6 months of age the sensitivity of the DNA-PCR test was 90% to 100%. In a direct comparison with coculture, the Roche DNA-PCR test was significantly more sensitive than coculture in the detection of HIV-1 in infected infants and was equivalent to coculture for the diagnosis of HIV in infants when a standardized algorithm was used to define infection status.
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PMID:Diagnosis of infection with human immunodeficiency virus type 1 by a DNA polymerase chain reaction assay among infants enrolled in the Women and Infants' Transmission Study. 876 13

Enzyme immunosorbent assays (ELISA) for human tumor necrosis factor-alpha (TNF-alpha) are available from many companies. Although this cytokine is meanwhile well established in scientific work its detection in human blood still leads often to conflicting results. We studied the analytical performance of three different commercial ELISA (Amersham, Immunotech and Medgenix Diagnostics) in plasma samples of 30 human immunodeficiency virus (HIV) infected individuals. All kits showed significantly different mean concentrations of TNF-alpha in the study population (p < 0.05). Kit A: 30.9 pg/ml +/- 46.6 vs. kit B: 46.9 pg/ml +/- 24.8 vs kit C: 11.8 pg/ml +/- 11.6. Results of assays A and B (r = 0.34) as well as A and C (r = 0.31) were not significantly correlated. A good statistical relation between values was only found for assay B and assay C (r = 0.80. p < 0.001). Three plasma samples were spiked with TNF-alpha standard of the corresponding kit to a final concentration of 200 pg/ml. The detection results of these samples were compared with the variation conceded by the manufacturer. Assay A detected two samples above the corresponding coefficient of intra-assay variation (recovery: 81.8% and 89.2%). All three values obtained with assay B were markedly out of its variation range (recovery: 88.7%, 84.6% and 89.0%) while assay C showed again two results above the intra-assay variation (recovery: 92.1% and 89.6%). In our observations we found relevant differences between commercial ELISA kits of different manufacturers, which made interpretation of TNF-alpha in human plasma samples difficult. Additionally, it should be taken into consideration that plasma specimen may contain cytokine-binding proteins or autoantibodies which are capable of blocking epitopes of TNF-alpha. This may lead to the loss of the necessary immunoreactivity which prevents detection antibodies from recognizing these molecules.
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PMID:A comparative study of different enzyme immunosorbent assays for human tumor necrosis factor-alpha. 881 19

A number of quantitative assays have been developed by using amplification techniques to measure human immunodeficiency virus type 1 RNA in the plasma of infected individuals. The Virology Committee of the AIDS Clinical Trials Group in the Division of AIDS, National Institute of Allergy and Infectious Diseases, has established a quality assurance program (QAP) for quantitative assays of HIV-1 RNA levels in plasma. The primary objective of the QAP was to ascertain that a laboratory could maintain the precision required to have a 90% power to detect a fivefold difference in RNA copy number between two samples in the same batch. To achieve this goal, the QAP required an intra-assay standard deviation of no greater than 0.15 log10 RNA copies per ml. Panels for proficiency testing consisted of coded replicate samples and a common set of standards. To date, 41 laboratories have participated in the program and have used both commercial and in-house assays. We demonstrated that 65% of the laboratories were capable of attaining the necessary level of intra-assay precision. The fitted regressions indicated that the differences among laboratories that used the same kit were generally greater than the differences among population-average regressions for the kits themselves. The use of an external QAP and a common set of standards reduced differences both among laboratories that used the same kit and among laboratories that used different kits. Thus, use of a common set of standards across clinical trial protocols would allow for cross-protocol comparisons.
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PMID:Evaluation of a quality assurance program for quantitation of human immunodeficiency virus type 1 RNA in plasma by the AIDS Clinical Trials Group virology laboratories. 889 67

The diagnosis of infection caused by Mycobacterium tuberculosis is of increased public health concern following increases in the number of cases in developed countries and major increases in developing countries associated with the spread of human immunodeficiency virus (HIV) infection. The specificity of purified protein derivative skin testing for the detection of infection is compromised by exposure to environmental mycobacteria. Examination of sputum detects the most infectious patients, but not those with extrapulmonary disease. The 38-kDa antigen of M. tuberculosis contains two M. tuberculosis-specific B-cell epitopes. We overexpressed the gene for this antigen in Escherichia coli and evaluated the recombinant product in in vitro assays of T-cell function and as a target for the antibody response in humans. The sensitivity and specificity of the antigen as a skin test reagent were also assessed in outbred guinea pigs. We found that 69% of healthy sensitized humans recognize the antigen in vitro, as manifested by both cell proliferation and the production of gamma interferon. Untreated patients initially have a lower frequency of response (38%); this recovers to 72% during therapy. A total of 292 patients (20 with HIV coinfection) and 58 controls were examined for production of antibody to the 38-kDa antigen by using a commercially available kit. The sensitivity of the test in comparison with that of culture was 72.6%, and the specificity was 94.9%. The antigen was also tested for its ability to induce skin reactions in outbred guinea pigs sensitized by various mycobacterial species. The antigen provoked significant skin reactions in M. tuberculosis-, M. bovis BCG-, and M. intracellulare-sensitized animals. The significance of these findings and the usefulness of this antigen in immunodiagnosis are discussed.
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PMID:Evaluation of the recombinant 38-kilodalton antigen of Mycobacterium tuberculosis as a potential immunodiagnostic reagent. 904 87

We studied the sensitivity of polymerase chain reaction (PCR) for detecting early human immunodeficiency virus-1 (HIV-1) in sex workers. Blood samples of sex workers who attended our Sexually Transmitted Diseases clinic were tested for HIV infection by testing for the presence of HIV antibody and HIV-1 proviral DNA using PCR (with the Amplicor HIV-1 amplification kit, Roche) at 00 (when they first register to work as sex workers), 01 and 03 months after starting work. The objective was to detect HIV-1 using PCR in sex workers during the "window" period when their HIV antibody tests were still negative. Sixty-nine blood samples were PCR-tested at 00 month of which 8 were simultaneously positive for HIV antibody and PCR tests. Seventy-seven blood samples were tested at 03 month. We found that PCR test using the Amplicor HIV-1 amplification kit (Roche) to be sensitive in detecting HIV infection in sex workers but the test appeared not sensitive enough to detect HIV-1 infection during the "window" period. We were unable to detect any sex workers with PCR detectable HIV-1 before they seroconverted to become HIV antibody positive. The reason for the failure was attributed to the low infection rate among sex workers and possible lack of sensitivity of the Amplicor PCR/HIV-1 amplification kit to detect early HIV-1 infection. We are currently studying other PCR procedures to improve the sensitivity of the PCR test for HIV-1.
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PMID:Molecular detection of human immunodeficiency virus-1 infection among commercial sex workers using the polymerase chain reaction in Singapore. 905 12

The silicon phthalocyanine HOSiPcOSi(CH3)2(CH2)3 N(CH3)2 (Pc 4), is being studied as a photosensitizer for virus inactivation in red blood cell concentrates (RBCC). The RBCC spiked with cell-free human immunodeficiency virus (HIV) or with HIV actively replicating in the T-lymphocytic cell line CEM can be successfully inactivated (> or = 6 log10) when exposed to 2 microM Pc 4 and 90 J/cm2 red light (600-800 nm). Inactivation of > or = 6 log10 inducible HIV in the latently infected promonocytic cell line U1 occurred at 22.5 J/cm2 (H. Margolis-Nunno et al., Transfusion 36, 743-750, 1996). In order to understand the reason for the increased susceptibility of U1 to photosensitized inactivation we looked for induction of apoptosis by photodynamic treatment (PDT). Agarose gel electrophoresis was used to observe the appearance of a characteristic 180-200 base pair DNA ladder, which can indicate apoptosis. Using this assay it is shown that Pc 4 treatment induced apoptosis in U1 cells in a light dose-dependent manner, starting 30 min after light exposure. Using the ApopTag Plus kit (which attaches a fluorescent label to the 3'-OH ends of the degraded DNA) and flow cytometry, the percentage of cells undergoing apoptosis was quantitated. At 10.5 J/cm2, 3 h after light exposure, about 92.5% of the cells were apoptotic. Under these conditions 99% of the cells eventually die. The CEM cells similarly treated underwent apoptosis at slower kinetics and required higher light doses. Other cell lines latently infected with HIV (ACH-2 and OM 10.1) were as sensitive as U1 to HIV inactivation by Pc 4-PDT (H. Margolis-Nunno et al., Transfusion 36, 743-750, 1996) and underwent apoptosis at a similar kinetic. These results suggest that the enhanced inactivation of HIV in latently infected cells compared to CEM cells by Pc 4-PDT may be due, at least in part, to apoptosis in the former.
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PMID:Silicon phthalocyanine Pc 4 and red light causes apoptosis in HIV-infected cells. 907 31

The relationship between treatment outcome and location of cryptococcal infection, gender, magnitude of pretreatment cryptococcal antigen titers, results of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) serology, and serial changes in antigen titers during and after treatment were evaluated in a prospective and nonrandomized study of 35 cats with cryptococcosis. A commercial cryptococcal latex agglutination kit (CALAS; Meridian Diagnostic Inc, Cincinnati, OH) was used to detect cryptococcal antigen in sera. All cats were treated with itraconazole (Sporanox; Janssen Pharmaceutica Inc, Titusville, NJ). Pretreatment mean log titers for serum cryptococcal antigen were not influenced by location of the infection. Treatment outcome was not influenced by gender, location of the infection, or magnitude of pretreatment serum antigen titer. Treatment outcome was influenced by FeLV and FIV status; cats seropositive for FeLV or FIV had a higher likelihood of treatment failure (P = .008). The cryptococcal antigen titers of cats successfully treated decreased with significant linearity over time during treatment (r = -.64, P < .000001), whereas the corresponding titers for cats not treated successfully did not decrease with significant linearity (r = -.03, P > .9). For cats in which treatment was successful, antigen titers decreased significantly from pretreatment values by 1.3 orders of magnitude at 2 months after initiation of treatment. By 10 months after initiating treatment, log titers decreased by at least 2 orders of magnitude in all cats successfully treated, and 9 of 16 cats had undetectable titers. In contrast, in 5 of 6 cats in which treatment failed, antigen titers were unchanged or increased in magnitude even after at least 6 months of treatment.
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PMID:Cryptococcal infection in cats: factors influencing treatment outcome, and results of sequential serum antigen titers in 35 cats. 913 77


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