1,720,965 research outputs found
Comparison of the Aptima HIV-1 Quant Dx Assay with the COBAS® AmpliPrep/COBAS® TaqMan® HIV-1 v2.0 Test for HIV-1 Viral Load Quantification in Plasma Samples from HIV-1-Infected Patients.
Full text linkBackground and aims: HIV‐1 RNA viral load (VL) in plasma samples of HIV‐1–positive
patients is used to assess the level of viral replication, the risk of disease progression, and the
response and efficacy to antiretroviral treatment. Knowing the performance of different tests
for HIV‐1 RNA detection is, therefore, important for clinical care. This study compared the performance
of the recently introduced Aptima HIV‐1 Quant Dx assay (Hologic, Inc) and the standard
COBAS AmpliPrep/COBAS TaqMan HIV‐1 v2.0 Test (CAP/CTM2) (Roche Molecular System,
Inc) for HIV‐1 RNA quantitation.
Methods: Assay performance was assessed using 335 clinical samples, a standard HIV‐1 low
VL panel, and 2 diluted samples from well‐characterized patients infected with different HIV‐1
subtypes tested in 5 replicates over 3 days. All samples were tested on both assays to evaluate
inter‐assay agreement, both qualitatively and quantitively. Altogether, we evaluated assay sensitivity,
linearity, accuracy, precision, repeatability, and reproducibility.
Results: Assay agreement for qualitative results in 335 clinical samples was fair (80.6%). Correlation
of quantitative assay results (n = 164) was excellent (R2 = 0.97), with 96.3% of the results
within the 95% limit of assay agreement (−0.42 to +0.86 log), and 98.8% within 1 log of each
other. Aptima‐HIV‐1 yielded results, on average, 0.22 log higher than CAP/CTM2. Both assays
accurately quantitated the HIV‐1 standard at low VL (R2 ≥ 0.94), with all samples within 0.5 log
of the target.
Conclusion: Aptima‐HIV‐1 assay demonstrated sensitivity, accuracy, reproducibility, and precision
for the detection and quantitation of HIV‐1 RNA across a wide dynamic range of VLs. Its
performance, together with full automation and high throughput, suggests that Aptima‐HIV‐1
could be a suitable assay for reliable monitoring of HIV‐1 VL in patients undergoing treatment
Acute onset myopericarditis as unusual presentation of primary HIV infection
No full textA 30-year-old man was admitted to hospital after complaining of a retrosternal burning pain, radiating to the jugular region, and to both upper limbs. An electrocardiography examination showed a ST segment elevation involving the lower-lateral leads. A trans-thoracic ultrasonography showed findings compatible with an acute myopericarditis. All performed serological testings excluded other recent infections with cardiac tropism. Among screening tests, a peripheral lymphocyte subset analysis was performed and an inversion of the CD4/CD8 ratio was found. Therefore, HIV testing was performed and proved positive for HIV-1 antibodies. The discovery of a primary HIV infection with involvement of a vital organ led us to start HAART. On day 20, our patient underwent a right heart catheterization and endomyocardial biopsy. During the following days, the clinical conditions of our patient improved, and a further heart ultrasonography documented a mild pericardial thickening as a result of the recent myopericarditis. Also the evolving changes of ECG were compatible with a benign evolution of myopericarditis. The histopathologic studies revealed a mild fibrosis of the myocardial right ventricular tissue, and inflammatory findings compatible with a recent myocarditis. At the real-time PCR analysis on bioptic sample, only HHV6 DNA and HIV-DNA were reactive. An immunofluorescence staining was performed to highlight the HIV p24 protein and a positive signal was detected in myocardial tissue. Considering the low avidity level of the anti-HIV IgG antibodies and the positivity of HIV-DNA in the endomyocardial tissue, we believe that the clinical manifestation presented can be referred to the recent primary HIV-infection
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Effects of Antiretroviral Molecules on Survival and Gene Expression of An Osteoblast-like Cell Line
No full textThe advent of combined antiretroviral therapy effectively undermined the evolution of HIV disease. Nevertheless, clinical observations indicated a clear association between therapy and the impairment of bone mineral density
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