1,720,962 research outputs found
The Endocannabinoid System as a Target for Neuroprotection/Neuroregeneration in Perinatal Hypoxic–Ischemic Brain Injury
Full text linkThe endocannabinoid (EC) system is a complex cell-signaling system that participates in a vast number of biological processes since the prenatal period, including the development of the nervous system, brain plasticity, and circuit repair. This neuromodulatory system is also involved in the response to endogenous and environmental insults, being of special relevance in the prevention and/or treatment of vascular disorders, such as stroke and neuroprotection after neonatal brain injury. Perinatal hypoxia–ischemia leading to neonatal encephalopathy is a devastating condition with no therapeutic approach apart from moderate hypothermia, which is effective only in some cases. This overview, therefore, gives a current description of the main components of the EC system (including cannabinoid receptors, ligands, and related enzymes), to later analyze the EC system as a target for neonatal neuroprotection with a special focus on its neurogenic potential after hypoxic–ischemic brain injury
Synergic action of MicroRNAs and Wnts delivered by motor neuron EVs in promoting AChR clustering
Full text linkBackground: The neuromuscular junction (NMJ) establishment occurs through complex communication events between motor neurons and muscle fibers; however, the molecular mechanisms leading to NMJ formation have yet to be fully elucidated. Little is known about the significance of extracellular vesicles (EVs) in mediating the interaction between motor neurons and muscle fiber in the NMJ establishment; this study investigates the role of motor neuron-derived EVs during the earliest stages of NMJ formation. Methods: NSC-34 cells have been used as a model of motor neurons; EVs have been isolated during neurite development using a serial ultracentrifugation protocol specifically adjusted to isolate large and small EVs. Isolated EVs were quantified through Nanoparticles Tracking Assay and characterized by Western Blot and TEM analyses. The microRNA (miRNA) cargo of EV subpopulations was identified by small-RNA sequencing and the predicted miRNA downstream targets were investigated. Results: NGS analysis of small RNAs carried by NSC-34-derived EVs identified a total of 245 EV specific miRNAs, most of which are up-regulated in NSC-34 cells and EVs during neurite stretching. Target prediction analysis evidenced how these miRNAs synergically target the Wnt signaling pathway. Moreover, we found that NSC-34-derived EVs carry Wnt proteins, including Wnt11, Wnt4 and Wnt3a. Since several studies suggested a role for the Wnt-associated signaling network in NMJ formation, we investigated the potential role of NSC-34 EVs in NMJ development and demonstrated that EV administration to myotubes increases acetylcholine receptor (AChR) cluster formation, as revealed by immunofluorescence staining with α-bungarotoxin. Moreover, myotube treatment with NSC-34-derived EVs led to GSK3β and JNK phosphorylation, followed by β-catenin nuclear translocation, suggesting that neuron-derived EVs can induce AChR clustering through Wnt pathway activation. Conclusion: These data demonstrate that EVs released from differentiated motor neurons carry multimodal signals, miRNAs, and Wnts, which can stimulate AChR clustering in myotubes, a fundamental preparatory stage for NMJ formation. These new data highlight that EVs may play a role in the NMJ establishment and function under physiological and pathological conditions, particularly neurodegenerative diseases
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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