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[Treatment goals of pulmonary hypertension].
Full text linkÖzet– Pulmoner hipertansiyon alanındaki önemli gelişmelerden
sonra, en önemli görevlerden biri uzun dönem sonuçlarla ilişkili kinik tedavi hedeflerini belirleme gereksinimidir. Modifiye New York
Kalp Cemiyeti fonksiyonel sınıf I veya II, 380 metreden fazla 6 dakika yürüme mesafesine ulaşma, ekokardiyografide sağ ventrikül
boyutunun ve fonksiyonunun normalleşmesi, B-tip natriüretik peptit
düzeyinin azalması ya da normalleşmesi ve sağ atriyal basıncının
8 mmHg’den düşük ve kardiyak indeksin 2,5 L/dk/m2
’den büyük
olması güncel hedeflerdir. Bununla birlikte, egzersiz kapasitesi ve
sağ kalp fonksiyonu gibi uzun dönem sonuçlarla daha fazla ilişkili
olan parametreleri hedefleyen daha güçlü ve net sınırlarla çizen
“eşiğin” daha yüksek tutulması gerektiği açık hale gelmektedir;
Özellikle, manyetik rezonans görüntüleme ve BNP/N-terminal pro
B tip natriüretik peptit gibi doğru ve noninvaziv olarak sağ ventrikül fonksiyonunu belirleyen testler, temel belirleyiciler ve tedavi
hedefleri olarak hizmet etmek için umut verici göstergeler olarak
ortaya çıkmaktadır. Ayrıca, sonuçlar üzerine odaklı çalışmalar tek
başına hiçbir testin güvenilir bir şekilde uzun vadeli prognostik
belirteç olarak kullanılamayacağını ve birleşik tedavi hedeflerinin
uzun dönem sonuçlarının daha iyi öngördüreceğini gösterdi. Yeniden düzenlenen tedavi hedeflerinin şunlar olduğu ileri sürülmüştür:
Modifiye New York Kalp Cemiyeti fonksiyonel sınıf I veya II, ≥380
ve 440 m arasındaki 6 dakika yürüme mesafesi, kardiyopulmoner
egzersiz testi-15 ml/d/kg’dan fazla tepe oksijen tüketim ölçümü ve
45 l/dak’dan az karbondioksit için solunum eşdeğeri, normale yakın
BNP değeri, ile normal/normale yakın sağ ventrikül boyut ve fonksiyonlarını gösteren ekokardiyografi ve/veya kardiyak manyetik rezonans görüntüleme ve 8 mmHg’den az sağ atriyal basınçla ve 2,5-3
l/dak/m2’den fazla kardiyak indeksle birlikte sağ ventrikül fonksiyonunun normalleştiğini gösteren hemodinamik parametreler. (J Am
Coll Cardiol 2013;62:D73–81)With significant therapeutic advances in the field of pulmonary arterial hypertension, the need to identify clinically relevant treatment goals that correlate with long-term outcome has emerged as 1 of the most critical tasks. Current goals include achieving modified New York Heart Association functional class I or II, 6-min walk distance >380 m, normalization of right ventricular size and function on echocardiograph, a decreasing or normalization of B-type natriuretic peptide (BNP), and hemodynamics with right atrial pressure <8 mm Hg and cardiac index >2.5 L/dk/m2. However, to more effectively prognosticate in the current era of complex treatments, it is becoming clear that the "bar" needs to be set higher, with more robust and clearer delineations aimed at parameters that correlate with long-term outcome; namely, exercise capacity and right heart function. Specifically, tests that accurately and noninvasively determine right ventricular function, such as cardiac magnetic resonance imaging and BNP/N-terminal pro-B-type natriuretic peptide, are emerging as promising indicators to serve as baseline predictors and treatment targets. Furthermore, studies focusing on outcomes have shown that no single test can reliably serve as a long-term prognostic marker and that composite treatment goals are more predictive of long-term outcome. It has been proposed that treatment goals be revised to include the following: modified New York Heart Association functional class I or II, 6-min walk distance 380 to 440 m, cardiopulmonary exercise test-measured peak oxygen consumption >15 ml/min/kg and ventilatory equivalent for carbon dioxide <45 l/min/l/min, BNP level toward "normal," echocardiograph and/or cardiac magnetic resonance imaging demonstrating normal/near-normal right ventricular size and function, and hemodynamics showing normalization of right ventricular function with right atrial pressure <8 mm Hg and cardiac index >2.5 to 3.0 l/min/m2. (J Am Coll Cardiol 2013;62:D73-81) ©2013 by the American College of Cardiology Foundation
End points and clinical trial design in pulmonary arterial hypertension
No full textNew and emerging therapies might provide benefit in patients with pulmonary arterial hypertension. Their efficacy and safety will be compared with existing combination therapies in randomized clinical trials. Appropriate end points for these trials need to be identified: these will include exercise testing, the composite end point of time to clinical worsening, and hemodynamic markers, including advanced imaging modalities and biomarkers. Quality-of-life questionnaires are useful and important secondary end points; pulmonary arterial hypertension-specific questionnaires are currently being developed. Advantages and disadvantages of various trial designs, including placebo-controlled monotherapy or add-on trials, noninferiority studies, and withdrawal trials are also discusse
Oral Treprostinil for the Treatment of Pulmonary Arterial Hypertension in Patients on Background Endothelin Receptor Antagonist and/or Phosphodiesterase Type 5 Inhibitor Therapy (The FREEDOM-C Study): A Randomized Controlled Trial
No full textBackground: Infused and inhaled treprostinil are effective for treatment of pulmonary arterial hypertension (PAH), although their administration routes have limitations. This study assessed the efficacy and safety of bid oral sustained-release treprostinil in the treatment of PAH with a concomitant endothelin receptor antagonist (ERA) and/or phosphodiesterase type 5 inhibitor. Methods: A 16-week, multicenter, double-blind, placebo-controlled study was conducted in 350 patients with PAH randomized to placebo or oral treprostinil. All patients were stable on background ERA, PDE-5 inhibitor, or both. Primary end point was Hodges-Lehmann placebo-corrected median difference in change from baseline 6-min walk distance (6MWD) at week 16. Secondary end points included time to clinical worsening, change in World Health Organization functional class, Borg dyspnea score, and dyspnea fatigue index score. Results: Thirty-nine patients (22%) receiving oral treprostinil and 24 patients (14%) receiving placebo discontinued the study. Placebo-corrected median difference in change from baseline 6MWD at week 16 was 11 m (P 5.07). Improvements in dyspnea fatigue index score (P 5.01) and combined 6MWD and Borg dyspnea score (P 5.01) were observed with oral treprostinil vs placebo treatment. Patients who achieved a week-16 bid oral treprostinil dose of 1.25 to 3.25 mg and 3.5 to 16 mg experienced a greater change in 6MWD (18 m and 34 m, respectively) than patients who achieved a bid dose of < 1 mg or discontinued because of adverse events (4 m). Conclusions: The primary end point of improvement in 6MWD at week 16 did not achieve significance. This study enhanced understanding of oral treprostinil titration and dosing, which has set the stage for additional studie
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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