1,721,031 research outputs found
Interplay between K-RAS and miRNAs
Get PDFK-RAS is frequently mutated in cancers, and its overactivation can lead to oncogene-induced senescence (OIS), a barrier to cellular transformation. Feedback onto K-RAS limits its signaling to avoid senescence while achieving the appropriate level of activation that promotes proliferation and survival. Such regulation could be mediated by miRNAs, as aberrant RAS signaling and miRNA activity coexist in several cancers, with miRNAs acting both up- and downstream of K-RAS. Several miRNAs both regulate and are regulated by K-RAS, suggesting a noncoding RNA-based feedback mechanism. Functional interactions between K-RAS and the miRNA machinery have also begun to unfold. This review comprehensively surveys the state of knowledge connecting K-RAS to miRNA function and proposes a model for the regulation of K-RAS signaling by noncoding RNAs
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Importance of the Niche: Wnt Signaling and Stem Cell Plasticity in Intestinal Homeostasis and Disease
No full textColorectal cancer (CRC) is the second most common cause of cancer deaths in the Western world. Its molecular pathology is well characterized and has taught us much about the normal physiology of the tissue that lines the gut lumen and gives rise to tumours. Central to our understanding of what drives cancer in this tissue was the discovery that mutations in the adenomatous polyposis coli gene (APC) are common to most tumours and that both familial and sporadic cancers in gut tissue are driven by mutations in APC (Su et al. 1992; Moser et al. 1992). A key function that explained the high penetrance of APC mutations in this tissue is its role in mediating signalling by Wnt (Polakis 1999). Specifically important is the ability of APC to act as a scaffold in assembling a protein complex that regulates the availability of β-catenin, which in turn regulates the activity of transcription factors that drive the expression of genes important for proliferation and differentiation (Rubinfeld et al. 1996; Polakis 2007). Signalling by Wnt has emerged not only as a key factor in driving the initiation of CRC but is also as a crucial regulator of normal tissue maintenance in the gut epithelium (Polakis 2007; Bejsovec 1999; Muncan et al. 2006). In particular, it plays an important role in specifying cell fate in this highly dynamic tissue. The APC protein is involved in many other functions that include regulation of cytoskeletal proteins to affect migration (Näthke et al. 1996; Kroboth et al. 2007), contribution to apoptosis (Steigerwald et al. 2005; Brocardo et al. 2008), nuclear import (Murawala et al. 2009), and mitotic spindles and related checkpoints (Dikovskaya et al. 2004, 2007; Draviam et al. 2006). In the background of the increased proliferation and decreased differentiation that accompanies mutations of APC, loss of the normal execution of these additional functions renders cells particularly prone to accumulate additional mutations that confer a significant survival advantage to APC mutant cells in gut epithelial tissue (McCartney and Näthke 2008).</p
Proapoptotic Function of the Retinoblastoma Tumor Suppressor Protein
No full textThe retinoblastoma protein (pRB) tumor suppressor blocks cell proliferation by repressing the E2F transcription factors. This inhibition is relieved through mitogen-induced phosphorylation of pRB, triggering E2F release and activation of cell-cycle genes. E2F1 can also activate proapoptotic genes in response to genotoxic or oncogenic stress. However, pRB's role in this context has not been established. Here we show that DNA damage and E1A-induced oncogenic stress promote formation of a pRB-E2F1 complex even in proliferating cells. Moreover, pRB is bound to proapoptotic promoters that are transcriptionally active, and pRB is required for maximal apoptotic response in vitro and in vivo. Together, these data reveal a direct role for pRB in the induction of apoptosis in response to genotoxic or oncogenic stress.National Institutes of Health (U.S.) (Grant 2-P01-CA42063
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
- …
