1,720,977 research outputs found
The HOPS Complex Subunit VPS39 controls ciliogenesis through autophagy
No full textPrimary cilia are microtubule-based organelles that assemble and protrude from the surface of most mammalian cells during quiescence. The biomedical relevance of cilia is indicated by disorders ascribed to cilia dysfunction, known as ciliopathies, that display distinctive features including renal cystic disease. In this report, we demonstrate that VPS39, a component of the homotypic fusion and vacuole protein sorting (HOPS) complex, acts as a negative regulator of ciliogenesis in human renal cells, by controlling the localization of the intraflagellar transport 20 (IFT20) protein at the base of cilia through autophagy. Moreover, we show that VPS39 controls ciliogenesis through autophagy also in vivo in renal tubules of Medaka fish. These observations suggest a direct involvement of the HOPS complex in the regulation of autophagy-mediated ciliogenesis and eventually in target selection. Interestingly, we show that the impact of autophagy modulation on ciliogenesis is cell-type dependent and strictly related to environmental stimuli. This report adds a further tile to the cilia-autophagy connection and suggests that VPS39 could represent a new biological target for the recovery of the cilia-related phenotypes observed in the kidneys of patients affected by ciliopathies
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
The Oral-facial-digital type I syndrome: a model to study renal cystic disease in ciliopathies
No full textThe Oral-Facial-Digital type I syndrome (OFDI; MIM 311200) is a rare syndromic form of inherited renal cystic disease. It is transmitted as an X-linked dominant, male lethal disorder and is caused by mutations in the OFD1 gene. Previous studies demonstrated that OFDI belongs to the growing number of disorders ascribed to dysfunction of primary cilia. Among the different clinical signs OFD type I is characterized by the presence of renal cystic disease, which is present in over 60% of cases. With the purpose of studying the role of the Ofd1 transcript in renal cystic disease, we generated two conditional Ofd1 deficient mouse models (Ksp and IND), which resulted in viable mice characterized by renal cystic disease and progressive impairment of renal function. The study of these models allowed us to demonstrate that primary cilia initially form and then disappear after the development of cysts, suggesting that the dysfunction of primary cilia is a consequence rather than the primary cause of renal cystic disease. Immunofluorescence and western blotting analysis revealed upregulation of the mTOR pathway in both dilated and non dilated renal structures. Treatment with rapamycin, a specific inhibitor of the mTOR pathway, resulted in a significant reduction in the number and size of renal cysts and a decrease in the cystic index compared with untreated mutant animals, suggesting that cystogenesis in our model is mTOR-dependent. mTOR is frequently deregulated in inherited forms of cystic kidney although the molecular mechanisms underlying this phenomenon are still to be determined. The use of both in vitro and in vivo systems allowed us to demonstrate that OFD1 has a role in the formation of the pre-initiation complex of translation (PIC). We showed that OFD1 coimmunoprecipitates with two subunits ( and ) of the eIF3 complex and colocalizes at the centrosome with subunits of the PIC. In addition, we also demonstrated that OFD1 is present in polysomes extracted from kidneys and interacts in vivo with subunits of the eIF3 complex. Microarray experiments performed on mRNA extracted from polysomes indicate impaired translation for a number of transcripts. These results indicate for the first time a role of OFD1 in the formation of the PIC and in the regulation of translation. Among the putative targets we focused our attention on GH and our data suggest that higher levels of the GH due to the impairment of translation may be responsible for the upregulation of the mTOR pathway.
All together our results shed light on the pathogenetic mechanisms underlying this rare inherited form of renal cystic disease and propose new possible link between renal cystic disease and deregulation of the mTOR pathway
- …
