1,720,993 research outputs found
Cholinergic effects mediated by M2 muscarinic receptor in human Schwann-like cells induced from adipose mesenchymal stem cells
No full textCholinergic effects mediated by M2 muscarinic receptor in human Schwann-like cells induced from adipose mesenchymal stem cells
Piovesana R.1,2, Faroni A.2, Tata AM1, Reid A.2
1Dept. Biol and Biotech. C. Darwin, University of Rome “Sapienza”, Rome, Italy;
2Blond McIndoe Lab, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK;
Schwann cells (SCs) have an important role in peripheral nerve regeneration but there are several restrictions on their clinical application. Adipose derived stem cells (ASCs) present good properties for cell therapies. When exposed to selective growth factors, they can acquire a SC-like phenotype (dASCs), expressing key SCs markers. Our group has demonstrated in rat model that M2 muscarinic receptor causes in vitro, a reversible arrest of cell proliferation, increasing SCs myelinating phenotype. Human dASCs, as rat dASCs, express muscarinic receptors. In the present work we evaluate if M2 muscarinic receptor activation may contribute to human dASCs proliferation and phenotype. M2 selective activation by selective agonist APE, causes a decreased cell proliferation, modulating the expression of gene involved in the proliferative state (i.e. c-jun and egr2) and neurotrophic factors. Although further analyses are needed to best characterise the role of M2 receptor, these data are the first evidence that its selective activation may have effects also on human dASCs proliferation and may favourite a neuroprotective environment relevant for nerve regeneration
Cholinergic effects mediated by M2 muscarinic receptor in human Schwann-like cells induced from adipose mesenchymal stem cells
No full textSchwann cells (SCs) have an important role in peripheral nerve regeneration but there are several restrictions hindering their clinical application. Adipose derived stem cells (ASCs) feature good properties for cell therapies. When exposed to specific growth factors in vitro, they can acquire a SC-like phenotype (dASCs), expressing key SCs markers. Our group has demonstrated that M2 muscarinic receptor in rat dASCs causes a reversible arrest of cell proliferation, increasing SCs myelinating phenotype. Human dASCs, as rat dASCs, express muscarinic receptors. In the present work we evaluate if M2 muscarinic receptor activation may contribute to human dASCs proliferation, migration and phenotype. M2 selective activation by selective agonist Arecaidine Propargyl Ester (APE) causes a decreased cell proliferation, modulating the expression of genes involved in the proliferation/differentiation (i.e. c-jun and egr2) and several neurotrophic factors. Moreover, M2 selective activation is able to decrease cell migration. Although further analyses are needed to best characterise the role of M2 receptor, these results are the first evidence that its selective activation may have effects also on human dASCs proliferation and migration. This may improve our knowledge of these promising therapeutic cells for potential use in nerve regeneration
Muscarinic receptor in Schwann-like adipose derived stem cells: implications in nerve regeneration.
No full textSchwann Cells (SCs) play a central role in the physiology and in the response of the axon injury. The capacity of SCs to proliferate, to secrete growth factors, to modulate immune response, to migrate and to re-myelinate regenerating nerves have been reported (Jessen et al, 2016). However, SCs present limited clinical application, such as the difficulty in collection and culture and the slow rate of in vitro expansion.
Some papers describe that Adipose-derived stem cells (ASCs) have the ability to differentiate towards SCs phenotype (Schwann-like, dASC) following exposure to suitable culture media (Kingham et al, 2007). dASC, like SCs, express functional receptors for different neurotrasmitters, including muscarinic receptor subtypes (M1-M4) that regulate some physiological events.
In the present work, we have characterised the effects mediated by muscarinic receptors on proliferation and neurotrophic factors (NFs) expression and production
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
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