1,721,348 research outputs found
Outsourcing CILEA per l'Ospedale "E. Morelli"
Full text linkIn questo articolo viene presentata l'attività di gestione remota compiuta dalla sezione Gestione Sistemi del CILEA per l'Azienda Ospedaliera "E. Morelli"di Sondalo
NOVEL FUNCTIONS OF THE SNARE PROTEIN SNAP29IN MEMBRANE TRAFFICKING AND CELL DIVISION
Full text linkVesicular trafficking within cells is an important process for tissue development and homeostasis. A key step of vesicular trafficking is the fusion between two membranes, a process in which SNARE (Soluble NSF Attachment Protein Receptors) proteins play a fundamental role. SNAP29 (SyNaptosomal Associated Proteins 29) is a ubiquitous SNARE, regulating membrane fusion in different trafficking compartments and in different contexts in non dividing cells. We isolated a loss of function mutant in usnp, the gene encoding the Drosophila homolog of the human protein SNAP29 (Snap29 hereafter), that, when made homozygous in developing epithelial organs, disrupts epithelial architecture. In vivo, we find that Snap29 interacts with multiple SNARE proteins, localizes to a number of trafficking organelles, and is required for proper Golgi Apparatus morphology. In addition, we show that Snap29 is required for fusion of autophagosomes with lysosomes together with Syx17 and Vamp7, and that lack of Snap29 results in excess secretion, suggesting that Snap29 might act negatively in regulation of vesicle fusion at the plasma membrane.
Interestingly, at the onset of mitosis, when trafficking compartments re-shape to allow the formation of the mitotic spindle, Snap29 is found at the outer KT in Drosophila S2 cells and localizes at spindle microtubules and centrosomes in mammalian cells. Depletion of Snap29 in Drosophila and mammalian cells leads to spindle assembly defects, associated to pro-metaphase delay in mammalian cells, and to the formation of daughter cells containing mininuclei. Mechanistically, lack of SNAP29 correlates with absence at KT of ZWINT-1 and ZWILCH, a component of RZZ complex, and with weak KTs-MTs attachments. In addition, we find that SPINDLY, the adaptor for recruitment to KTs of dynein/dynactin and MAD1, a component of the Spindle Assembly Checkpoint machinery, fail to be removed from KTs at the end of metaphase in SNAP29 depleted mammalian cells forced to reassemble the spindle after treatment with microtubules depolymerization drug.
Finally, we show that cell division is impaired in Snap29 mutant tissues in vivo, that autophagy defects are not the cause of the altered epithelial tissues architecture in Snap29 mutants and that the trafficking and cell division function of Snap29 are molecularly distinct.
All together our findings support a role of Snap29 at key steps of membrane trafficking and in cell division. Our study contribute to shed light on the pathogenesis of CEDNIK, a human congenital syndrome caused by SNAP29 inactivation. In addition to this, we propose that the function of SNAP29 in cell division might be evolutionarly related to that of complexes tethering MTs to vesicular organelles in interphase. We surmise that such function could be potentially relevant to development of aneuploidy in tumor-like masses
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
Seismostratigraphy and Sedimentology of the South Chile Margin: State of the Art and Future Prospects
No full textkoamabayili/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
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