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Plasma RNA viral load in human immunodeficiency virus type 2 subtype A and subtype B infections 总被引:4,自引:0,他引:4 下载免费PDF全文
Damond F Gueudin M Pueyo S Farfara I Robertson DL Descamps D Chène G Matheron S Campa P Brun-Vézinet F Simon F 《Journal of clinical microbiology》2002,40(10):3654-3659
Human immunodeficiency virus type 2 (HIV-2) is much less pathogenic than HIV-1, and HIV-2 infection is associated with plasma viral loads significantly lower than those found in HIV-1 infection. We have developed a real-time quantitative PCR method for measuring the HIV-2 RNA load that covers the range of genetic diversity of HIV-2 isolates and that detects extremely low viral loads. Samples from 49 patients were studied. Proviral DNA was first detected and quantified. The strains that were detected were then genotyped: 21 patients were infected with HIV-2 subtype A and 15 patients were infected with HIV-2 subtype B; 1 patient was infected with a highly divergent strain. Env PCR failed for the remaining 12 patients, so subtypes could not be determined. For viral RNA quantification, a stock of HIV-2 strain NIHZ, which was counted by electron microscopy, was used as the standard. Several primer sets targeting the highly conserved gag region were evaluated. Various primer combinations failed to amplify subtype B strains. With the final primer pair selected, which detected both subtype A and subtype B strains, the sensitivity of the assay was 100% at a viral load of 250 copies/ml and 66% at a viral load of 125 copies/ml. We found a correlation between the CD4(+)-cell count, the clinical stage, and the plasma HIV-2 RNA level. The median plasma HIV-2 RNA value for the 33 asymptomatic patients was 2.14 log(10), whereas it was 3.1 log(10) for the 16 patients with AIDS (P < 0.01). Proviral DNA was detectable in 18 symptom-free patients with high CD4(+)-cell counts, in whom viral RNA was undetectable. 相似文献
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Jacob E. Resch Cathleen N. Brown Stephen N. Macciocchi C. Munro Cullum Damond Blueitt Michael S. Ferrara 《Journal of Athletic Training》2015,50(12):1292-1298
ContextSymptom presentation and recovery after sport concussion (SC) are variable. Empirically based models documenting typical symptom duration would assist health care providers in managing return to play after SC.ObjectiveTo develop a prediction model for SC symptom duration.DesignCross-sectional study.SettingTwo National Collegiate Athletic Association Division I university laboratories.Intervention(s)Participants completed the Revised Head Injury Scale (HIS-r), Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), and Sensory Organization Test within 24 hours of SC diagnosis.ResultsThe final formula consisted of the HIS-r''s self-reported neck pain, drowsiness, tingling, and nervousness duration and ImPACT total symptom severity (R = 0.62, R2 = 39%, R2adj = 34.2%, P < .001). Approximately 29% (R2cv = 29%) of the variance associated with total days symptomatic after SC was explained by our preliminary formula when cross-validated. The current formula correctly identified 76% of participants who recovered within 10 days of injury.ConclusionsOur results suggest that self-reported duration of 4 symptoms during the initial 24 hours after injury along with total symptom severity as measured by ImPACT accounted for a considerable amount of variance associated with days symptomatic after SC in collegiate athletes. Until the formula is cross-validated in a college-aged sample, caution is warranted in using it clinically.Key Words: traumatic brain injuries, prediction, prolonged recovery, symptom severity, symptom duration
Key Points
- A formula to predict symptom resolution after sport concussion primarily consisting of initial symptom duration and severity correctly identified 76% of National Collegiate Athletic Association Division I collegiate athletes who recovered within 10 days.
- Before it can be used clinically, the formula must be cross-validated on larger samples.
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Damond F Benard A Balotta C Böni J Cotten M Duque V Ferns B Garson J Gomes P Gonçalves F Gottlieb G Kupfer B Ruelle J Rodes B Soriano V Wainberg M Taieb A Matheron S Chene G Brun-Vezinet F;ACHI 《Journal of clinical microbiology》2011,49(10):3491-3497
Accurate HIV-2 plasma viral load quantification is crucial for adequate HIV-2 patient management and for the proper conduct of clinical trials and international cohort collaborations. This study compared the homogeneity of HIV-2 RNA quantification when using HIV-2 assays from ACHI(E)V(2E) study sites and either in-house PCR calibration standards or common viral load standards supplied to all collaborators. Each of the 12 participating laboratories quantified blinded HIV-2 samples, using its own HIV-2 viral load assay and standard as well as centrally validated and distributed common HIV-2 group A and B standards (http://www.hiv.lanl.gov/content/sequence/HelpDocs/subtypes-more.html). Aliquots of HIV-2 group A and B strains, each at 2 theoretical concentrations (2.7 and 3.7 log(10) copies/ml), were tested. Intralaboratory, interlaboratory, and overall variances of quantification results obtained with both standards were compared using F tests. For HIV-2 group A quantifications, overall and interlaboratory and/or intralaboratory variances were significantly lower when using the common standard than when using in-house standards at the concentration levels of 2.7 log(10) copies/ml and 3.7 log(10) copies/ml, respectively. For HIV-2 group B, a high heterogeneity was observed and the variances did not differ according to the type of standard used. In this international collaboration, the use of a common standard improved the homogeneity of HIV-2 group A RNA quantification only. The diversity of HIV-2 group B, particularly in PCR primer-binding regions, may explain the heterogeneity in quantification of this strain. Development of a validated HIV-2 viral load assay that accurately quantifies distinct circulating strains is needed. 相似文献
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Levacher M Bouscarat F Landman R Chau F Damond F Gaudebout C Mathez D Leibowitch J Saimot AG Sinet M 《AIDS research and human retroviruses》2000,16(17):1869-1875
To assess prospectively the influence of the control of viral replication on the frequency of cytokine-producing T cells, and to correlate these changes with immune activation, we conducted a 15-month follow-up study of IFN-gamma- and IL-2-producing CD4+ and CD8+ T cells at a single-cell level in 12 previously untreated patients receiving highly active antiretroviral therapy (HAART). At baseline we observed a strikingly high proportion of IFN-gamma-producing CD8+ T cells. The treatment-induced decrease in the proportion of IFN-gamma-producing CD8+ T cells ran parallel to the decrease in HLA-DR+ and CD38+CD8+ T cell subsets and was associated with the reduction in HIV RNA level. IL-2-producing cells were mainly CD4+. As a consequence of CD4+ T cell loss, the number of IL-2-producing CD4+ T cells was lower in patients than in control subjects (52 vs. 171 cells/microl), but the proportion of these cells was unchanged (22.4 vs. 19.3). During therapy the proportion of CD4+ IL-2-producing cells was initially stable and then fell markedly at month 5, followed by a gradual return to previous values. The reduction in viral load was associated with the fall in the proportion of CD4+ activated subsets. Intracellular cytokine assays are a new approach to the assessment of T cell function in HIV infection. Our results suggest that the functional capacity of CD4+ T cells is probably less severely altered than previously thought on the basis of conventional assays. CD8+ T cells exhibit an increased capacity to produce IFN-gamma that is associated with an increase in activation marker expression. These alterations decrease partially and in parallel under treatment. 相似文献
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Couturier E Damond F Roques P Fleury H Barin F Brunet JB Brun-Vézinet F Simon F 《AIDS (London, England)》2000,14(3):289-296
OBJECTIVE: To study the distribution of HIV-1 subtypes in France and to describe the characteristics of patients infected with non-B subtypes. METHODS: All adults who tested HIV-1 positive on Western blot for the first time in one of the participating laboratories between September 1996 and March 1998 were eligible, whether or not they had been diagnosed previously elsewhere. Data on age, sex, country of birth, HIV-transmission group, dates of the last negative and first positive HIV test and clinical stage were collected. Serotyping was performed with a peptide subtype-specific enzyme immunoassay on each plasma sample and genotyping with heteroduplex mobility assay on each non-B serotype-infected patient. Patients characteristics were compared in B and non-B subtypes. RESULTS: Of the 2168 HIV-positive patients included by 32 laboratories, subtype,results were available for 2042. Among those, 73.4% were men, 12.2% born in sub-Saharan Africa, 41.5% infected through heterosexual contact and 67.6% in CDC stage A. Among the 2042 patients, 1 725 (84.5%) were infected with B subtype. Among the 317 non-B subtypes, subtype A was predominant (66.9%); all other subtypes (C, D, E, F, G, H, O) were present. Factors independently associated with a non-B subtype were to be included in the Paris area [adjusted odds ratio (aOR), 1.6; 95% confidence interval (CI), 1.1-2.3], to be born in sub-Saharan Africa (aOR, 26.0; 95% CI, 17.5-37.8) and to be infected through heterosexual contact (aOR, 4.2; 95% CI, 2.8-6.4). CONCLUSIONS: In France, although B subtype is still predominant, all non-B subtypes are now present. The diversity of HIV strains may affect diagnostic tests and clinical practice, especially viral load measurements. Moreover, the decreased susceptibility of non-B subtypes to antiretroviral drugs emphasizes the importance of surveillance of HIV diversity. 相似文献
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Damond F Benard A Ruelle J Alabi A Kupfer B Gomes P Rodes B Albert J Böni J Garson J Ferns B Matheron S Chene G Brun-Vezinet F;ACHIEVE Collaboration on HIV- Infection Study Group 《Journal of clinical microbiology》2008,46(6):2088-2091
Human immunodeficiency virus type 2 (HIV-2) RNA quantification assays used in nine laboratories of the ACHI(E)V(2E) (A Collaboration on HIV-2 Infection) study group were evaluated. In a blinded experimental design, laboratories quantified three series of aliquots of an HIV-2 subtype A strain, each at a different theoretical viral load. Quantification varied between laboratories, and international standardization of quantification assays is strongly needed. 相似文献