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    Transposition of the great arteries. Some gleams of light to pathogenetic knowledge

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    Transposition of the great arteries (TGA) is a frequent and severe cardiac defect. In patients with this malformation, diagnostic and surgical results and the long-term prognosis significantly improved in the last years. From the embryological point of view there are two main theories: 1) the anomalous infundibular rotation, and 2) the anomaly of the aortico-pulmonary septum. Both of them still present important limits. Moreover, TGA is difficult to reproduce by animal experiments, but interesting data, using retinoid acid in pregnant rats, are nowadays available, as well as there are interesting data from the epidemiologic studies on human teratologic agents. TGA is rarely associated with genetic syndromes and with additional extracardiac anomalies. A few cases are in relation with DiGeorge syndrome with deletion of chromosome 22q11. On the contrary TGA is significantly prevalent, in association with other cardiac and extracardiac anomalies, in children with lateralization defects, heterotaxy and asplenia syndrome (right isomerism). However in patients with heterotaxy and polysplenia syndrome (left isomerism) TGA is significantly more rare. In mice with mutation of Smad2 and NODAL, two genes involved in the lateralization process, some cases of TGA, with or without right isomerism of the lungs, were reported. Moreover, in families with heterotaxy some cases with congenitally corrected TGA were reported and a new gene associated with heterotaxy, CRYPTIC, can present mutations in patients with "isolated" TGA. A recent study on familiar recurrence of TGA shows in the same family some cases of TGA and of corrected TGA so that a monogenic inheritance (autosomic dominant or recessive) with variable phenotypic expression can be suggested. The normal righthand spiralization of the heart is genetically determined in cases of situs solitus and d-loop of the ventricles. This pattern is not present in cases of TGA presenting a parallel position of the great arteries. On the basis of these observations and according to new epidemiologic and genetic data some cases of TGA should be classified in the group of the anomalies of lateralization and ventricular loop. The mystery is still present but perhaps some gleams of light are appearing

    Microdeletion 22q11 and oesophageal atresia

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    Oesophageal atresia (OA) is a congenital defect associated with additional malformations in 30-70% of the cases. In particular, OA is a component of the VACTERL association. Since some major features of the VACTERL association, including conotruncal heart defect, radial aplasia, and anal atresia, have been found in patients with microdeletion 22q11.2 (del(22q11.2)), we have screened for del(22q11.2) by fluorescent in situ hybridisation (FISH) in 15 syndromic patients with OA. Del(22q11.2) was detected in one of them, presenting with OA, tetralogy of Fallot, anal atresia, neonatal hypocalcaemia, and subtle facial anomalies resembling those of velocardiofacial syndrome. The occurrence of del(22q11.2) in our series of patients with OA is low (1/15), but this chromosomal anomaly should be included among causative factors of malformation complexes with OA. In addition, clinical variability of del(22q11.2) syndrome is further corroborated with inclusion of OA in the list of the findings associated with the deletion

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

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    “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
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