291 research outputs found
Especialización del léxico en contexto: definiciones basadas en un corpus de videojuegos
El objetivo de esta comunicación es proponer definiciones para los nuevos usos de algunas palabras procedentes del lenguaje común y de uso muy frecuente en el ámbito del videojuego. En ese contexto, dichas palabras especializan su significado, en algunos casos como consecuencia de la aplicación de categorías narrativas (por ejemplo, “personajes” y “aventuras”) en la crítica de videojuegos. El estudio se basa en el análisis de un corpus de artículos de crítica de videojuegos publicados en españo
The ventrolateral hypothalamic area and the parvafox nucleus: Role in the expression of (positive) emotions?
The lateral hypothalamus has been long suspected of triggering the expression of positive emotions, because stimulations of its tuberal portion provoke bursts of laughter. Electrophysiological studies in various species have indeed confirmed that the lateral hypothalamus contributes to reward mechanisms. However, only the rudiments of the neural circuit underlying the expression of positive emotions are known. The prefrontal cortex, the lateral hypothalamus, and the periaqueductal gray matter (PAG) are involved in these circuits; so, too, are the brainstem nuclei that control the laryngeal muscles and subserve mimicry, as well as the cardiovascular and respiratory systems. The implicated populations of hypothalamic neurons have not been defined either anatomically or molecularly. One promising candidate is the novel parvafox nucleus, which we recently described, in the murine medial forebrain bundle (mfb), which specifically expresses parvalbumin and Foxb1. With the molecularly defined parvafox nucleus as a centerpiece, the inputs from the prefrontal cortex and the projections to the PAG and brainstem can be studied with precision. By drawing on genetic approaches, it will be possible to manipulate the circuitry selectively with spatial and temporal exactitude and to evaluate the concomitant autonomic changes. These data will serve as a basis for imaging studies in humans using various paradigms to provoke the expression of positive emotions. In conclusion, studies of the hypothalamic parvafox nucleus will reveal whether this entity represents the fulcrum for positive emotions, as is the amygdala for fear and the insula for disgust
Coaxiality of Foxb1- and parvalbumin-expressing neurons in the lateral hypothalamic PV1-nucleus
In the ventrolateral hypothalamus, the PV1-nucleus is defined by its population of parvalbumin-expressing neurons. During embryogenesis, the ventrolateral hypothalamus is colonized also by Foxb1-expressing neurons. In adult Foxb1-EGFP mice, many immunofluorescent neurons were found within the region that is occupied by the PV1-nucleus. They formed a cloud around the axial cord of the parvalbumin-immunopositive cells, which they greatly outnumber (3:1). Only a small proportion of the neurons in the PV1-nucleus co-expressed both parvalbumin and Foxb1. In the light of these findings, a redesignation of this lateral hypothalamic structure as the PV1-Foxb1 nucleus would more accurately reflect its specific biochemical properties
The Foxb1‐expressing neurons of the ventrolateral hypothalamic parvafox nucleus project to defensive circuits
The parvafox nucleus is an elongated structure that is lodged within the ventrolateral hypothalamus and lies along the optic tract. It comprises axially located parvalbumin (Parv)-positive neurons and a peripheral cuff of Foxb1-expressing ones. In the present study, injections of Cre-dependent adenoviral constructs were targeted to the ventrolateral hypothalamus of Foxb1/Cre mice to label specifically and map the efferent connections of the Foxb1-expressing subpopulation of neurons of the parvafox nucleus. These neurons project more widely than do the Parv-positive ones and implicate a part of the axons known to emanate from the lateral hypothalamus. High labeling densities were found in the dorsolateral and the upper lateral portion of the periaqueductal gray (PAG), the Su3 and PV2 nuclei of the ventrolateral PAG, the cuneiform nucleus, the mesencephalic reticular formation, and the superior colliculus. Intermediate densities of terminals were encountered in the septum, bed nucleus of the stria terminalis, substantia innominata, various thalamic and hypothalamic nuclei, pedunculopontine nucleus, Barrington's nucleus, retrofacial nucleus, and retroambigual nucleus. Scattered terminals were observed in the olfactory bulbs, the prefrontal cortex and the lamina X of the cervical spinal cord. Because the terminals were demonstrated to express the glutamate transporter VGlut2, the projections are presumed to be excitatory. A common denominator of the main target sites of the Foxb1-positive axons of the parvafox nucleus appears to be an involvement in the defensive reactions to life-threatening situations. The hypothalamic parvafox nucleus may contribute to the autonomic manifestations that accompany the expression of emotions
La localización de videojuegos: un caso de colaboración interdisciplinaria
Uno de los ámbitos de localización de software que muestra un mayor desarrollo en la actualidad, es el de los videojuegos. La localización de videojuegos es algo más que una traducción, supone la adaptación de los elementos relacionados con el idioma sin alterar los demás componentes del software. Esta comunicación es el resultado de la colaboración interdisciplinaria entre una traductora experta en localización de videojuegos y una filóloga que trabaja en el ámbito del léxico del videojuego. En ese contexto, se analizan algunas dificultades planteadas por la adaptación de inglés a español de una serie de términos muy frecuentes en el lenguaje de los videojuegos, permitiendo conocer la actitud de los localizadores ante los neologismos y la creación de nuevo léxico
Birthdate of parvalbumin-neurons in the Parvafox-nucleus of the lateral hypothalamus
The Parvafox-nucleus in the lateral hypothalamus is characterized by the presence of two distinct neural populations, the Parvalbumin (Parv) and the Foxb1-expressing ones. Foxb1-neurons are born at day 10 in the subventricular zone of the mouse mammillary region. It would be interesting to know if the subpopulation of Parv- neurons develop independently at different times and then meet the Foxb1- expressing neurons in the lateral hypothalamus, their final settling place. The aim of this study was to define the period of birth of the Parv-positive neurons using an in-vivo Bromodeoxyuridine-based method in rats. Parv-neurons are generated from embryonic day 10 to day 13, with a peak at day 12. Thus, it appears that the birthdates of the two subpopulations in these two species is similar, perhaps suggesting that they are born from the same neuroepithelial region
Sonic hedgehog lineage in the mouse hypothalamus: from progenitor domains to hypothalamic regions
<p>Abstract</p> <p>Background</p> <p>The hypothalamus is a brain region with essential functions for homeostasis and energy metabolism, and alterations of its development can contribute to pathological conditions in the adult, like hypertension, diabetes or obesity. However, due to the anatomical complexity of the hypothalamus, its development is not well understood. <it>Sonic hedgehog </it>(<it>Shh</it>) is a key developmental regulator gene expressed in a dynamic pattern in hypothalamic progenitor cells. To obtain insight into hypothalamic organization, we used genetic inducible fate mapping (GIFM) to map the lineages derived from <it>Shh-</it>expressing progenitor domains onto the four rostrocaudally arranged hypothalamic regions: preoptic, anterior, tuberal and mammillary.</p> <p>Results</p> <p><it>Shh-</it>expressing progenitors labeled at an early stage (before embryonic day (E)9.5) contribute neurons and astrocytes to a large caudal area including the mammillary and posterior tuberal regions as well as tanycytes (specialized median eminence glia). Progenitors labeled at later stages (after E9.5) give rise to neurons and astrocytes of the entire tuberal region and in particular the ventromedial nucleus, but not to cells in the mammillary region and median eminence. At this stage, an additional <it>Shh</it>-expressing domain appears in the preoptic area and contributes mostly astrocytes to the hypothalamus. <it>Shh-</it>expressing progenitors do not contribute to the anterior region at any stage. Finally, we show a gradual shift from neurogenesis to gliogenesis, so that progenitors expressing Shh after E12.5 generate almost exclusively hypothalamic astrocytes.</p> <p>Conclusions</p> <p>We define a fate map of the hypothalamus, based on the dynamic expression of <it>Shh </it>in the hypothalamic progenitor zones. We provide evidence that the large neurogenic <it>Shh-</it>expressing progenitor domains of the ventral diencephalon are continuous with those of the midbrain. We demonstrate that the four classical transverse zones of the hypothalamus have clearly defined progenitor domains and that there is little or no cell mixing between the tuberal and anterior or the preoptic and anterior hypothalamus. Finally, we show that, in the tuberal hypothalamus, neurons destined for every mediolateral level are produced during a period of days, in conflict with the current 'three-wave' model of hypothalamic neurogenesis. Our work sets the stage for a deeper developmental analysis of this complex and important brain region.</p
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