1,720,960 research outputs found

    Influence of hydroxychloroquine blood levels on adhesion molecules associated with endothelial dysfunction in patients with systemic lupus erythematosus

    No full text
    Background Patients with SLE have an endothelial dysfunction (ED), which is considered the earliest marker of cardiovascular (CV) disease. Endothelial cell activation induced by proinflammatory cytokines is defined by the endothelial expression of cell-surface adhesion molecules, such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin. The aim of this study was to investigate whether serum endothelial adhesion molecule levels are influenced by blood hydroxychloroquine (HCQ) levels in SLE. Methods Consecutive patients with SLE taking a stable dose of HCQ were investigated. At study entry and 6 months later HCQ blood levels were quantified by tandem mass spectrometry. Serum levels of P-selectin, E-selectin, ICAM-1 and VCAM-1 were also measured using a Luminex 200 instrument. Comparison of endothelial soluble adhesion molecules in groups with different HCQ blood levels was performed by t-test. Results 83 patients with SLE were enrolled. Correlation were demonstrated between mean blood HCQ concentrations and endothelial soluble adhesion molecules (E-selectin, ICAM-1 and VCAM-1). Moreover, serum levels of ICAM-1 and VCAM-1 were significantly lower in the patients with SLE with HCQ blood levels >500 ng/mL (83.67 +/- 52.8 ng/mL vs 158.81 +/- 125.1 ng/mL and 8.9 +/- 2.2 ng/mL vs 10.4 +/- 2.3 ng/mL). Serum levels of E-selectin were nearly significantly lower in the patients with SLE with HCQ blood levels >500 ng/mL (64.7 +/- 30.2 ng/mL vs 71.6 +/- 42.2 ng/mL, p=0.06). No significant difference in concentration of P-selectin was detected. Conclusions In the present study, there was a trend towards higher adhesion molecules levels with lower HCQ blood levels in patients with SLE. Further longitudinal studies will determine whether changes in endothelial biomarkers reflect decreased clinical CV events

    Hydroxychloroquine daily dose, hydroxychloroquine blood levels and the risk of flares in patients with systemic lupus erythematosus

    No full text
    BACKGROUND: Recent guidelines for SLE recommend using a hydroxychloroquine (HCQ) dose less than 5.0 mg/kg/day to reduce the risk of retinopathy. To determine if this dose reduction would have an impact on the clinical course of SLE, we compared flare incidence in a cohort of patients with SLE treated with two different oral HCQ dosages (≤5 mg/kg/day or >5 mg/kg/day). As a secondary analysis, we compared HCQ blood levels between the two different oral dosages, and evaluated the frequency of non-adherence in patients with SLE treated with HCQ. METHODS: We identified a cohort of patients with SLE taking HCQ for at least 6 months and followed for 24 months. At study entry and 6 months later, a blood venous sample was taken to measure HCQ blood levels by liquid chromatography. Incidence of new SLE flares after recruitment was put in relation to daily HCQ dose and mean HCQ blood levels. Cox regression analysis served to identify factors associated with SLE flares. RESULTS: 83 patients were enrolled. We observed 11 (16%) flares that developed in mean 14.8 months of follow-up. The difference in terms of flare rate and mean HCQ blood levels between the two oral dosages was not statistically significant. There was a trend (p=0.08) for high HCQ dose being associated with a lower flare rate. At Cox analysis, higher HCQ blood levels and older age at baseline were protective against flare occurrence, while concomitant immunosuppressant therapy showed significant positive association. HCQ blood levels did not correlate with prescribed HCQ dose. CONCLUSION: Patients with low oral HCQ dosage tend to have more flares, although the difference was not statistically significant. Higher HCQ blood levels were protective against flare occurrence. The risks and benefits must be balanced in choosing HCQ dose

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Get PDF
    The 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

    Get PDF
    “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

    Get PDF
    We 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

    Get PDF
    We 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

    Author Index

    No full text
    Nao informado

    koamabayili/VECTRON-author-checklist: VECTRON author checklist

    No full text
    We 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
    corecore