1,721,056 research outputs found
Cardiomyocyte differentiation from human induced pluripotent stem cells is delayed following knockout of Bcl-2
Anti-apoptotic B-cell lymphoma 2 (Bcl-2) regulates a wide array of cellular functions involved in cell death, cell survival and autophagy. Less known is its involvement in the differentiation of cardiomyocytes. As a consequence, mechanisms by which Bcl-2 contributes to cardiac differentiation remain to be elucidated. To address this, we used CRISPR/Cas9 to knockout (KO) BCL2 in human induced pluripotent stem cells (hiPSCs) and investigated the consequence of this KO for differentiation towards cardiomyocytes. Our results indicate that differentiation of hiPSCs to cardiomyocytes was delayed following BCL2 KO. This was not related to the canonical anti-apoptotic function of Bcl-2. This delay led to reduced expression and activity of the cardiomyocyte Ca2+ toolkit. Finally, Bcl-2 KO reduced c-Myc expression and nuclear localization in the early phase of the cardiac differentiation process, which accounts at least in part for the observed delay in the cardiac differentiation. These results suggest that there is a central role for Bcl-2 in cardiomyocyte differentiation and maturation.sponsorship: This work was supported by the Research Foundation-Flanders (Fonds Wetenschappelijk Onderzoek, FWO) 'krediet aan navorsers' (grant number: 1508319N) awarded to T.V. and a FWO research grant (grant number G066821N) awarded to M.S. T.V. is a recipient of a senior post-doctoral grant of the FWO (grant number: 12ZG121N) . R.D. was supported by KU Leuven Rondoufonds voor Duchenne Onderzoek (EQQ-FODUCH-O2010) and KU Leuven Postdoctoral Mandate Type 1 (PDMT1/21/037) . A.P. is supported by KULeuven C1 grant C14/21/093 awarded to H.L.R. (Research Foundation-Flanders (Fonds Wetenschappelijk Onderzoek, FWO)|1508319N, FWO research grant|G066821N, FWO|12ZG121N, KU Leuven Rondoufonds voor Duchenne Onderzoek|EQQ-FODUCH-O2010, KU Leuven Postdoctoral Mandate Type 1|PDMT1/21/037, KULeuven C1 grant|C14/21/093)status: Publishe
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
IP3R activity increases propensity of RyR-mediated sparks by elevating dyadic [Ca2+].
Calcium (Ca2+) plays a critical role in the excitation contraction coupling (ECC) process that mediates the contraction of cardiomyocytes during each heartbeat. While ryanodine receptors (RyRs) are the primary Ca2+ channels responsible for generating the cell-wide Ca2+ transients during ECC, Ca2+ release, a=via inositol 1,4,5-trisphosphate (IP3) receptors (IP3Rs) are also reported in cardiomyocytes and to elicit ECC-modulating effects. Recent studies suggest that the localization of IP3Rs at dyads grant their ability to modify the occurrence of Ca2+ sparks (elementary Ca2+ release events that constitute cell wide Ca2+ releases associated with ECC) which may underlie their modulatory influence on ECC. Here, we aim to uncover the mechanism by which dyad-localized IP3Rs influence Ca2+ spark dynamics. To this end, we developed a mathematical model of the dyad that incorporates the behaviour of IP3Rs, in addition to RyRs, to reveal the impact of their activity on local Ca2+ handling and consequent Ca2+ spark occurrence and its properties. Consistent with published experimental data, our model predicts that the propensity for Ca2+ spark formation increases in the presence of IP3R activity. Our simulations support the hypothesis that IP3Rs elevate Ca2+ in the dyad, sensitizing proximal RyRs toward activation and hence Ca2+ spark formation. The stochasticity of IP3R gating is an important aspect of this mechanism. However, dyadic IP3R activity lowers the Ca2+ available in the junctional sarcoplasmic reticulum (JSR) for release, thus resulting in Ca2+ sparks with similar durations but lower amplitudes
Appropriate Similarity Measures for Author Cocitation Analysis
We 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
We 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
We 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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