1,720,996 research outputs found

    Lacosamide: a new approach to target voltage-gated sodium currents in epileptic disorders

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    The mechanism of action of several antiepileptic drugs (AEDs) rests on their ability tomodulate the activity of voltage-gated sodium currents that are responsible for fast action potentialgeneration. Recent data indicate that lacosamide - a compound with analgesic and anticonvulsanteffects in animal models - shares a similar mechanism. When compared with other AEDs, lacosamidehas the unique ability to interact with sodium channel slow inactivation without affecting fastinactivation. This article reviews these findings and discusses their relevance within the context ofneuronal activity seen during epileptiform discharges generated by limbic neuronal networks in thepresence of chemical convulsants. These seizure-like events are characterized by sustained dischargesof sodium-dependent action potentials supported by robust depolarizations thus providingsynchronization within neuronal networks. Generally, AEDs such as phenytoin, carbamazepine andlamotrigine block sodium channels when activated. By contrasts, lacosamide facilitates slowinactivation of sodium channels both in term of kinetics and voltage-dependency. This effect may berelatively selective for repeatedly depolarized neurons such as those participating in seizure activity inwhich the persistence of sodium currents is more pronounced and promotes neuronal excitation. Theclinical effectiveness of lacosamide has been demonstrated in randomized placebo-controlled doubleblindparallel-group, adjunctive-therapy trials in patients with refractory partial seizures. Furtherstudies should determine whether lacosamide effects in animal models and in clinical settings are fullyexplained by its selective action on sodium current slow inactivation or whether other effects (e.g.,interactions with the collapsin-response mediator protein 2) play a contributory role

    Epileptiform synchronization in the cingulate cortex

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    The anterior cingulate cortex (ACC)--which plays a role in pain, emotions and behavior--can generate epileptic seizures. To date, little is known on the neuronal mechanisms leading to epileptiform synchronization in this structure. Therefore, we investigated the role of excitatory and inhibitory synaptic transmission in epileptiform activity in this cortical area. In addition, since the ACC presents with a high density of opioid receptors, we studied the effect of opioid agonism on epileptiform synchronization in this brain region

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

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    “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

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    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

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    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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