1,720,997 research outputs found
Identification of a novel gene involved in Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia
Full text linkArrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a genetic cardiac disease inherited as an autosomal dominant trait with incomplete penetrance and variable expressivity. Its main feature is the progressive substitution of the myocardium with fatty or fibro-fatty tissue, involving predominantly the right ventricle. Clinically, ARVC/D is characterized by ventricular arrhythmias, often associated with syncope and sudden cardiac death, especially in the young and athletes. Up to now, several disease genes have been identified, including 5 encoding desmosomal proteins. In this study, mutation screening for desmosomal genes performed in 80 consecutive unrelated Italian probands failed to detect mutation in about half of index cases, thus suggesting further genetic heterogeneity. On the basis of alphaT-catenin (a protein of cardiac area composita) cellular localization and function, mutation screening was then performed in CTNNA3 candidate gene in 76 affected subjects, negative for mutations in desmosomal genes. Four mutations have been detected. In vitro functional studies assessed the pathogenicity for two of them. For the first time mutations in CTNNA3 have been detected in a human disease. Particularly, the recurrence of pathogenic mutations in CTNNA3 gene in ARVC/D patients expands the concept of this disease beyond desmosomesLa cardiomiopatia aritmogena del ventricolo destro (ARVC/D) è una malattia genetica cardiaca, ereditata come carattere autosomico dominante a penetranza incompleta ed espressività variabile. La sua caratteristica principale è la progressiva sostituzione del miocardio del ventricolo destro con tessuto adiposo e/o fibroadiposo, con formazione di circuiti anatomici di rientro e conseguenti aritmie e morte improvvisa, specie nei giovani. Attualmente sono noti dieci geni malattia, di cui cinque sono codificanti per le proteine desmosomali. In questo studio, lo screening di mutazioni nei geni desmosomali eseguito in 80 pazienti affetti non ha evidenziato mutazioni in circa la metà dei casi, suggerendo la presenza di ulteriore eterogeneità genetica. In virtù della funzione e della localizzazione cellulare dell’alphaT-catenina (proteina dell’area composita), è stato svolto lo screening di mutazioni nel gene candidato CTNNA3 in 76 casi indice negativi per mutazioni nei geni desmosomali. Sono state identificate quattro variazioni. Studi funzionali in vitro hanno dimostrato la patogenicità per due di esse. Per la prima volta, mutazioni nel gene CTNNA3 sono state associate a una malattia umana. In particolare, la ricorrenza di mutazioni patogene nel gene CTNNA3 in pazienti ARVC/D estende il concetto di questa malattia oltre i desmosom
Arrhythmogenic right-ventricular cardiomyopathy: Molecular genetics into clinical practice in the era of next generation sequencing
No full textSudden death, ventricular arrhythmia and heart failure are common features in arrhythmogenic right-ventricular cardiomyopathy (ARVC), an inheritable heart muscle disease, characterized by clinical and genetic heterogeneity. So far, 13 disease genes have been identified, responsible for around 60% of all ARVC cases. In this review, we summarize the main clinical and pathological aspects of ARVC, focusing on the importance of the genetic testing and the application of the new sequencing techniques referred to next generation sequencing technology
Genetics meets epigenetics: Genetic variants that modulate noncoding RNA in cardiovascular diseases
No full textAfter the recent description of the human genome by the ENCODE and the FANTOM consortia, major attention has been addressed to the so-called "genomic noise", which mainly consists of noncoding RNAs (ncRNAs). Among them, microRNAs and long non-coding RNAs have been demonstrated to modulate gene expression and to be involved in several human diseases. Since ncRNAs and their targets are encoded in the genome, genetic principles apply. Common variants are supposed to influence the expression level and the functionality of ncRNAs, with subsequent differential regulation of their target genes. Moreover, several reports showed that polymorphisms in ncRNA or their target genes play a role in the development of cardiovascular adverse phenotype. Here, we provide an overview of the effects of these variations in cardiovascular diseases
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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