1,720,965 research outputs found
A novel myogenic cell line with phenotypic properties of muscle progenitors
No full textSkeletal myogenesis is a multistep process starting
with progenitor cell proliferation, followed by their exit
from the cell cycle, differentiation, alignment, and fusion to
form multinucleated myotubes, typical of the differentiated
muscle tissue. While the molecular players involved in
early myogenesis have been extensively characterized,
information about the later steps of the process is scanty.
Here, we describe a novel myogenic cell line (MYOP7),
composed of highly proliferating Sca-1+ muscle precursor
cells, which can be induced to terminally differentiate into
spontaneously contracting multinucleated myotubes. By
performing high-density microarray analysis on these cells,
we identified a series of genes, differentially expressed in
proliferating vs differentiating conditions, which are candidates
to play a major role in the later phase of myogenesis.
In addition, we confirmed that the late stages of muscle
differentiation are characterized by a marked upregulation
of the cellular receptors for the vascular endothelial growth
factor
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
Bone marrow mononuclear cells are recruited to the sites of VEGF-induced neovascularization but are not incorporated into the newly formed vessels
No full textVascular endothelial growth factor (VEGF)
is a key regulator of blood vessel formation
during both vasculogenesis and angiogenesis.
The prolonged expression of
VEGF in the normoperfused skeletal
muscles of adult rodents after gene transfer
using AAV vectors induces the formation
of a large set of new capillaries and
small arteries. Notably, this process is
accompanied by the massive infiltration
by mononuclear cells. This observation
raises the possibility that these cellsmight
represent circulating progenitors that are
eventually incorporated in the newly
formed vessels. Here we explore this possibility
by exploiting 4 different experimental
models based on (a) the transplantation
of male bone marrow into female
recipients; (b) the transplantation of Tie2-
GFP transgenic bone marrow; (c) the
transplantation of bone marrow in the
presence of erythropoietin (EPO), a mobilizer
of endothelial progenitor cells
(EPCs); and (d) the reimplantation of ex
vivo–expanded EPCs. In all 4 models,
VEGF acted as a powerful attractor of
bone marrow–derived mononuclear cells,
bearing different myeloid and endothelial
markers proper of the EPCs to the sites of
neovascularization. In no case, however,
were the attracted cells incorporated in
the newly formed vasculature. These observations
indicate that new blood vessel
formation induced by VEGF occurs
through bona fide sprouting angiogenesis;
the contribution of the infiltrating
bone marrow–derived cells to this process
still remains enigmatic
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
AAV-Mediated Delivery of VEGF-B Preserves Viability and Cardiac Function Following Myocardial Infarction through a Direct Effect on Cardiomyocyte Survival and Contractility
No full textDispelling 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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