1,720,962 research outputs found
Statin therapy and related risk of new-onset type 2 diabetes mellitus
No full textThe use of statins for cardiovascular disease (CVD) prevention is clearly supported by clinical evidence. Although statin therapy is rather well tolerated, recent data from prospective and retrospective clinical trials and related meta-analyses suggest an increased incidence of new-onset type 2 diabetes mellitus (T2DM) in association with such treatment. The incidence of this adverse effect is not negligible, especially for specific subsets of patients, such as women, elderly, presence of familial history of T2DM and Asian ethnicity. Statin-driven T2DM appears to be a medication class-effect, mostly not related to potency nor to individual statin, as well as to be independent of previous history of CVD. Therefore, implementation of strategies for identification of patients using statins and at specific risk of incident T2DM, as well as of different therapeutic options is important and is discussed in this article. As most authors emphasized that benefits of CVD reduction by statin therapy seem to far exceed the risk of T2DM development itself, these medications remain the cornerstone for primary and secondary CVD prevention, although a specific attention to glucose metabolism and metabolic syndrome features should be payed before and during statin treatment, especially in cohorts at greater risk
Risk identification and possible countermeasures for muscle adverse effects during statin therapy
No full textThe use of statins for cardiovascular disease prevention is clearly supported by clinical evidence. However, in January 2014 the U.S. Food and Drug Administration released an advice on statin risk reporting that "statin benefit is indisputable, but they need to be taken with care and knowledge of their side effects". Among them the by far most common complication is myopathy, ranging from common but clinically benign myalgia to rare but life-threatening rhabdomyolysis. This class side effect appears to be dose dependent, with more lipophilic statin (i.e., simvastatin) carrying a higher overall risk. Hence, to minimize statin-associated myopathy, clinicians should take into consideration a series of factors that potentially increase this risk (i.e., drug-drug interactions, female gender, advanced age, diabetes mellitus, hypothyroidism and vitamin D deficiency). Whenever it is appropriate to stop statin treatment, the recommendations are to stay off statin until resolution of symptoms or normalization of creatine kinase values. Afterwards, clinicians have several options to treat dyslipidemia, including the use of a lower dose of the same statin, intermittent non-daily dosing of statin, initiation of a different statin, alone or in combination with nonstatin lipid-lowering agents, and substitution with red yeast rice
Impact Of Iron Overload On Reproductive Axis Impairment: Pathophysiological Insights From In Vitro And In Vivo Studies
No full textIntroduction: Iron is an essential micronutrient for proper brain development in the fetal/early neonatal period. Conversely, iron overload is the most important factor afflicting the hypothalamus-pituitary axis leading to hypogonadotropic hypogonadism. Methods: Male C57Bl6/J mice, GN-11 cells (immature/migratory GnRH neurons), qPCR/Western blotting analyses, Boyden’s chamber assay (chemomigration), Ferric Ammonium Citrate (FAC, source of ferric iron). Results: Dietary-iron overload (IED) significantly increased mice testis iron content (+49% vs. Control, CTR) and reduced testicular weight and length. Hypothalamic GnRH gene expression was increased in IED mice (+34% vs. CTR, p< 0.01), leaving Kiss1 and GPR54 unchanged. IED promoted reduction of pituitary LHβ mRNA levels. Treatment of GN-11 cells with 200 μM FAC: a) induced a significant increment of intracellular iron content (24 h; +10 fold vs. CTR); b) modulated transferrin receptor and ferritin H mRNA levels (24 h); c) inhibited FBS-induced chemomigration in dose- (200-1000 μM) and time- (24-72 h) dependent; d) modulated pERK1/2, pAkt and pAMPK protein levels (5-180 min; 5 fold, +95% and -50% vs. CTR, respectively; all p<0.05); e) inhibited GN-11 chemomigration via AKT modulation (as assessed by using a specific Akt inhibitor; 90 min). Conclusions: The impairment of the adult reproductive axis by iron overload, leading to hypogonadotropic hypogonadism, may include specific hypothalamic derangements, in addition to the known pituitary and gonadal changes. Moreover, iron overload appears to negatively affect in vitro GnRH neuron migratory ability, thereby possibly impairing GnRH cell migration from foetal olfactory placode into forebrain and hypothalamus, where these neurons subsequently promote the reproductive competence
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
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