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Sindrome da delezione del cromosoma 22q11.2: valutazione della funzione cardiorespiratoria, delle patologie extracardiache e correlazioni genotipo-fenotipo
Full text linkBackground
La sindrome da delezione del cromosoma 22q11.2 (22q11.2DS, OMIM 188400/192430) è la più comune sindrome da microdelezione cromosomica, con una prevalenza di circa 1:4000 nati vivi. Nonostante i progressi nella diagnosi e nel trattamento abbiano portato ad un miglioramento dell’aspettativa di vita e al raggiungimento dell’età adulta da parte di questi pazienti, i dati limitati che abbiamo a disposizione sulla popolazione adulta con 22q11.2DS hanno sottolineato un aumentato rischio di morte prematura per cause cardiovascolari (come la morte improvvisa o lo scompenso cardiaco), anche in assenza di cardiopatia congenita (CC). Lo scopo di questo studio è stato quello di valutare la funzione cardiaca e respiratoria a riposo e la tolleranza all'esercizio fisico in un gruppo di adolescenti e adulti con 22q11.2DS senza CC. Inoltre, sono state indagate le possibili correlazioni tra fenotipo cardiopolmonare, fenotipo extracardiaco e caratteristiche genetiche.
Materiali e Metodi
Sono stati arruolati 32 pazienti (20M,12F; età media 26.00 ± 8.08) con diagnosi di 22q11.2DS senza CC. Tutti i soggetti sono stati valutati da un team multidisciplinare per individuare le caratteristiche fenotipiche extracardiache, sono stati sottoposti a valutazione cardiologica completa con ECG, ecocardiografia transtoracica convenzionale e speckle tracking (STE), test di funzionalità respiratoria e test da sforzo cardiopolmonare. Sono stati raccolti i dati genetici dei pazienti sottoposti ad analisi array genomiche (CGH- e SNP-array), analizzando l’estensione e la localizzazione della delezione e l’eventuale presenza di microriarrangiamenti aggiuntivi, oltre alla microdelezione 22q11.2. E’ stata condotta un’analisi di correlazione genotipo-fenotipo tra gli aspetti funzionali cardiorespiratori, le anomalie extracardiache e l’assetto genetico. I risultati degli esami strumentali sono stati confrontati con un gruppo di controllo (GC) e i valori p≤0.05 sono stati considerati statisticamente significativi.
Risultati
I pazienti con 22q11.2DS hanno mostrato un aumento delle dimensioni del VS (IVSd p=0.005; LVIDd p=0.03; LVPWd p=0.05), della massa ventricolare sinistra indicizzata per l’altezza (LVMI g/m2,7 p<0.001) e del diametro del bulbo aortico (p<0.001) rispetto al GC. Nove pazienti (~28%) hanno mostrato una dilatazione lieve del bulbo aortico (Z-score 2-3) e 3 pazienti (~9%) una dilatazione moderata (Z-score 3,01-4). Il TDI ha rivelato una iniziale compromissione della funzione diastolica del VS e l’analisi STE ha identificato una riduzione dello “strain” miocardico longitudinale globale del VS (GLS Avg) nei pazienti affetti rispetto al GC (p<0.001). I valori di VO2max, FEV1% e FVC% sono risultati inferiori nei pazienti 22q11.2DS (p<0,001). La scoliosi, il BMI e lo stile di vita sedentario sembrano influenzare la funzione respiratoria. Nel gruppo 22q11.2DS, valori patologici di Z-score del bulbo aortico correlano significativamente con la presenza di patologie dell’apparato scheletrico/connettivo (p=0.04) e valori ridotti di GLS Avg del VS mostrano una relazione diretta con i disturbi GI (p=0.026). Sebbene, non sia emersa una correlazione significativa, circa il 67% dei pazienti con delezione “atipica” e distale presentava un GLS Avg del VS alterato. Tra i pazienti con alterazione del GLS Avg del VS, ~27% mostrava una delezione “atipica”, ~13% una delezione distale e ~7% presentava mutazioni genetiche aggiuntive, non correlate alla microdelezione 22q11.2.
Conclusione
I pazienti adolescenti/adulti 22q11.2DS senza CC, presentano segni iniziali di compromissione diastolica e sistolica del VS in fase subclinica, mantenendo una performance ventricolare complessivamente conservata e mostrano una dilatazione del bulbo aortico di grado lieve-moderato. Inoltre, è stata evidenziata una riduzione della funzionalità respiratoria e dell’efficienza cardiopolmonare. Pertanto, anche in assenza di CC, è opportuno che questi pazienti seguano un regolare follow-up cardiopolmonare fin dall’età pediatrica, per evidenziare potenziali comorbilità correlate, identificare l'insorgenza precoce di eventuali anomalie funzionali cardiorespiratorie e monitorare l’eventuale progressione di una dilatazione del bulbo aortico nel tempo. La stretta correlazione emersa tra alcune anomalie extracardiache e il fenotipo cardiorespiratorio può consentire una migliore stratificazione del rischio prognostico e prevenire possibile complicanze a lungo termine. Ulteriori studi di correlazione genotipo-fenotipo sono necessari per chiarire se la presenza di una delezione “atipica” e/o distale possa predisporre i pazienti con 22q11.2DS senza CC ad un maggior rischio di disfunzione miocardica ventricolare sinistra e quanto le eventuali mutazioni genomiche aggiuntive possano contribuire al fenotipo funzionale cardiopolmonare
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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