1,720,979 research outputs found
Influence of Abdominal Obesity on the Relationship of Low-Density Lipoprotein Cholesterol with Atherosclerosis and Cardiovascular Risk in Rheumatoid Arthritis
No full textObjective. Patients with rheumatoid arthritis (RA) and low body weight may incur higher all-cause and cardiovascular mortality than obese patients. Likewise, RA patients with low serum levels of low-density lipoprotein cholesterol (LDLc<70 mg/dl) may experience greater cardiovascular risk. We explored whether abdominal obesity (waist-to-height ratio >0.58 in females and >0.62 in males) associated with coronary atherosclerosis and influenced the relationship between low LDLc, coronary atherosclerosis and cardiovascular risk in RA.
Methods. Coronary artery calcium, number of coronary plaques, and extensive (≥5 plaques) or obstructive (>50% stenosis) disease was evaluated with computed tomography angiography in 150 patients at baseline and 101 patients 6.9±0.4 years later. Cardiovascular events were recorded. Oxidized LDL was measured with monoclonal antibody E06. Serum cholesterol loading capacity on macrophages was measured as intracellular cholesterol content with a fluorometric assay.
Results. Abdominal obesity was not associated with per-patient number of coronary plaques or coronary artery calcium score at baseline. Low LDLc positively associated with number of plaques (b 2.13 [95% confidence interval 1.03 to 3.22]), likelihood of extensive or obstructive plaque (odds ratio 6.58, 95% confidence interval [1.63 to 26.46]), and log-transformed CAC (b 1.90 [0.89 to 2.91]) exclusively in nonobese patients (p-for-interaction <0.001, 0.061, and 0.001 respectively). Low LDLc associated with increased likelihood of >median oxidized LDL and higher ratio of cholesterol loading capacity to LDLc in nonobese patients (p-for-interaction 0.041 and 0.001 respectively). Abdominal obesity negatively associated with likelihood of plaque stenosis progression (odds ratio 0.19 [0.07 to 0.54]). Low LDLc associated with greater
likelihood of per-segment plaque formation (OR 4.68 [2.26 to 9.66]) and
increased stenotic severity (odds ratio 5.35 [1.62 to 17.67]) only in nonobese patients (p-for-interaction 0.002 and 0.040 respectively). Abdominal obesity was not linked to cardiovascular risk (Hazard Ratio 1.57, 95% confidence interval [0.66-3.73]). Low LDLc associated with higher cardiovascular risk in nonobese (Hazard Ratio 7.94 [1.52 to 41.36]) but not obese patients (p-forinteraction=0.017).
Conclusion. Abdominal obesity was not linked to plaque progression or
cardiovascular risk in RA. Only in nonobese patients, low LDLc associated with higher atherosclerosis burden, plaque progression and cardiovascular risk. This may reflect higher oxidation and macrophage cholesterol loading capacity of LDL when LDLc is <70mg/dl
Lipoprotein oxidation may underlie the paradoxical association of low cholesterol with coronary atherosclerotic risk in rheumatoid arthritis
No full textObjective: To compare coronary plaque burden, proatherogenic cytokines, oxidized low-density lipoprotein (oxLDL), anti-oxLDL antibodies, lipoprotein(a)-cholesterol, and their relationships in patients with rheumatoid arthritis with low-density lipoprotein cholesterol (LDL-C)< 1.8 mmol/L versus > 1.8 mmol/L. Also, to study differences in inflammation and proprotein convertase subtilisin/kexin type-9 (PCSK9), which impacts LDL clearance, in patients with low versus high LDL-C. Methods: Computed tomography angiography evaluated coronary plaque (noncalcified, partially calcified, fully calcified, and high-risk plaque) in 150 patients from a single-center observational cohort. Ox-LDL, anti-oxLDL IgG, lipoprotein(a)-cholesterol, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), interleukin-6, tumor necrosis factor-alpha (TNF-alpha) and PCSK9 were measured. Analyses adjusted for Framingham general car-diovascular risk score, statin use, and high-density lipoprotein cholesterol. Results: Patients with LDL-C < 1.8 mmol/L versus >= 1.8 mmol/L demonstrated: 1) higher likelihood of per-segment plaque (adjusted-OR = 1.67 [95%CI = 1.10-2.55], p = 0.017) and high-risk plaque presence (adjusted-OR 2.78 [95%CI = 1.06-7.29], p = 0.038); 2) greater anti-oxLDL titers (p = 0.020), which positively associated with TNF-alpha and likelihood of noncalcified, partially calcified and high-risk plaque presence only in patients with LDL-C < 1.8 mmol/L (all p-for-interaction & LE;0.046); 3) increased lipoprotein(a)-cholesterol content (10.33% [8.11-12.54] versus 6.68% [6.10-7.25], p < 0.001), which positively associated with oxLDL (p < 0.001) and anti-oxLDL (p = 0.036); 4) higher interleukin-6 and PCSK9. No differences in CRP, ESR, or oxLDL were observed. Conclusion: RA patients with LDL-C < 1.8 mmol/L had more coronary plaque, higher anti-oxLDL titers and anti-oxLDL associated with plaque only in this group. It is possible the observed paradoxical association of low LDL-C with greater atherosclerosis may be related to higher production of the oxidation-prone lipoprotein(a)-cholesterol and anti-oxLDL antibodies, resulting in increased vascular LDL uptake and plaque formation
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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