1,720,961 research outputs found
Atrogin-1, MuRF1, and FoXo, as well as phosphorylated GSK-3β and 4E-BP1 are reduced in skeletal muscle of chronic spinal cord-injured patients
No full textChronic complete spinal cord injury (SCI) is associated with severe skeletal muscle atrophy as well several atrophy and physical-inactivity-related comorbidity factors such as diabetes, obesity, lipid disorders, and cardiovascular diseases. Intracellular mechanisms associated with chronic complete SCI-related muscle atrophy are not well understood, and thus their characterization may assist with developing strategies to reduce the risk of comorbidity factors. Therefore, the aim of this study was to determine whether there was an increase in catabolic signaling targets, such as atrogin-1, muscle ring finger-1 (MuRF1), forkhead transcription factor (FoXO), and myostatin, and decreases in anabolic signaling targets, such as insulin-like growth factor (IGF), v-akt murine thymoma viral oncogene (Akt), glycogen synthase kinase-β (GSK-3β), mammalian target of rapamycin (mTOR), eukaryotic initiation factor 4E binding protein 1 (4E-BP1), and p70s6kinase in chronic complete SCI patients. In SCI patients, when compared with controls, there was a significant reduction in mRNA levels of atrogin-1 (59%; P < 0.05), MuRF1 (55%; P < 0.05), and myostatin (46%; P < 0.01), and in protein levels of FoXO1 (72%; P < 0.05), FoXO3a (60%; P < 0.05), and atrogin-1 (36%; P < 0.05). Decreases in the protein levels of IGF-1 (48%; P < 0.001) and phosphorylated GSK-3β (54%; P < 0.05), 4E-BP1 (48%; P < 0.05), and p70s6kinase (60%; P = 0.1) were also observed, the latter three in an Akt-and mTOR-independent manner. Reductions in atrogin-1, MuRF1, FoXO, and myostatin suggest the existence of an internal mechanism aimed at reducing further loss of muscle proteins during chronic SCI. The downregulation of signaling proteins that regulate anabolism, such as IGF, GSK-3β, and 4E-BP1, would reduce the ability to increase protein synthesis rates. © 2009 Wiley Periodicals, Inc
The emergence of cold-induced brown adipocytes in mouse white fat depots is determined predominantly by white to brown adipocyte transdifferentiation.
Get PDFThe origin of brown adipocytes arising in white adipose tissue (WAT)
after cold acclimatization is unclear. Here, we demonstrate that
several UCP1-immunoreactive brown adipocytes occurring in WAT
after cold acclimatization have a mixed morphology (paucilocular
adipocytes). These cells also had a mixed mitochondrioma with
classic “brown” and “white” mitochondria, suggesting intermediate
steps in the process of direct transformation of white into brown
adipocytes (transdifferentiation). Quantitative electron microscopy
disclosed that cold exposure (6°C for 10 days) did not induce an
increase in WAT preadipocytes. 3-adrenoceptor-knockout mice had
a blunted brown adipocyte occurrence upon cold acclimatization.
Administration of the 3-adrenoceptor agonist CL316,243 induced the
occurrence of brown adipocytes, with the typical morphological
features found after cold acclimatization. In contrast, administration
of the 1-adrenoceptor agonist xamoterol increased only the number
of preadipocytes. These findings indicate that transdifferentiation
depends on 3-adrenoceptor activation, whereas preadipocyte recruitment
is mediated by 1-adrenoceptor. RT-qPCR experiments disclosed
that cold exposure induced enhanced expression of the thermogenic
genes and of genes expressed selectively in brown adipose
tissue (iBAT) and in both interscapular BAT and WAT. 3-adrenoceptor
suppression blunted their expression only in WAT. Furthermore,
cold acclimatization induced an increased WAT expression of
the gene coding for C/EBP (an antimitotic protein), whereas Ccna1
expression (related to cell proliferation) was unchanged. Overall, our
data strongly suggest that the cold-induced emergence of brown
adipocytes in WAT predominantly reflects 3-adrenoceptor-mediated
transdifferentiation
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
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
Decreased fatty-acid beta-oxidation in riboflavin-responsive, multiple acylcoenzyme A dehydrogenase-deficient patients is associated with an increase in uncoupling protein-3
No full texti.f. 5.19
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