981 resultados para interior frontal gyrus


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RATIONALE: Dopamine D2 receptors are the main target of antipsychotic drugs. In the brain, D2 receptors coexpress with adenosine A2A and CB1 cannabinoid receptors, leading to functional interactions. OBJECTIVES: The protein and messenger RNA (mRNA) contents of A2A, D2, and CB1 receptors were quantified in postmortem prefrontal cortex of subjects with schizophrenia. MATERIALS AND METHODS: The study was performed in subjects suffering schizophrenia (n=31) who mainly died by suicide, matched with non-schizophrenia suicide victims (n=13) and non-suicide controls (n=33). The density of receptor proteins was evaluated by immunodetection techniques, and their relative mRNA expression was quantified by quantitative real-time polymerase chain reaction. RESULTS: In schizophrenia, the densities of A2A (90+/-6%, n=24) and D2-like receptors (95+/-5%, n=22) did not differ from those in controls (100%). Antipsychotic treatment did not induce changes in the protein expression. In contrast, the immunodensity of CB1 receptors was significantly decreased (71+/-7%, n=11; p<0.05) in antipsychotic-treated subjects with schizophrenia but not in drug-free subjects (104+/-13%, n=11). The relative mRNA amounts encoding for A2A, D2, and CB1 receptors were similar in brains of drug-free, antipsychotic-treated subjects with schizophrenia and controls. CONCLUSIONS: The findings suggest that antipsychotics induce down-regulation of CB1 receptors in brain. Since A2A, D2, and CB1 receptors coexpress on brain GABAergic neurons and reductions in markers of GABA neurotransmission have been identified in schizophrenia, a lower density of CB1 receptor induced by antipsychotics could represent an adaptative mechanism that reduces the endocannabinoid-mediated suppression of GABA release, contributing to the normalization of cognitive functions in the disorder.

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La denominada «reestructuración rural» pasa ineludiblemente por la transformación de la economía de sector primario que tradicionalmente ha sustentado al campo. En los últimos tiempos, se experimenta una clara tercerización de la economía rural, en muy buena medida capitalizada por la industria turística. En este sentido, surge la necesidad de repensar la ruralidad, de construirla socialmente a partir de la proyección de imaginarios comunicados interna y externamente mediante la ayuda de marcas territoriales. El presente trabajo tiene como objetivo prioritario explorar de qué forma la marca espacial Territoris serens permite la creación de una imagen competitiva para la agrupación territorial del Lluçanès, por medio de la difusión de relatos asociados a diversos valores intangibles encabezados por la serenidad, el paisaje y, por ende, la identidad territorial. La revisión de la literatura referida a marcas de territorio, el análisis de la producción documental vinculada a Territoris serens y la organización de un grupo focal de discusión permitirá dirimir el proceso de transformación de territorios en marcas, en aras de conseguir, en nombre de la competitividad, un renovado y posmoderno «sentido de lugar

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Se explica de qué manera afecta la música a los seres vivos y cómo se puede aprender a usar la Musicoterapia para manejar situaciones de estrés.

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Glutamatergic gliotransmission provides a stimulatory input to excitatory synapses in the hippocampal dentate gyrus. Here, we show that tumor necrosis factor-alpha (TNFα) critically controls this process. With constitutive TNFα present, activation of astrocyte P2Y1 receptors induces localized [Ca(2+)](i) elevations followed by glutamate release and presynaptic NMDA receptor-dependent synaptic potentiation. In preparations lacking TNFα, astrocytes respond with identical [Ca(2+)](i) elevations but fail to induce neuromodulation. We find that TNFα specifically controls the glutamate release step of gliotransmission. In cultured astrocytes lacking TNFα glutamate exocytosis is dramatically slowed down due to altered vesicle docking. Addition of low picomolar TNFα promptly reconstitutes both normal exocytosis in culture and gliotransmission in situ. Alternatively, gliotransmission can be re-established without adding TNFα, by limiting glutamate uptake, which compensates slower release. These findings demonstrate that gliotransmission and its synaptic effects are controlled not only by astrocyte [Ca(2+)](i) elevations but also by permissive/homeostatic factors like TNFα. VIDEO ABSTRACT:

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This paper reports a series of experiments on patient JB, a man with memory difficulties following damage to the left frontal lobe. The primary characteristic of JB's recognition memory impairment is a high level of false recognition together with a normal hit rate. The hypothesis that JB's false recognition reflects an over-reliance on familiarity is considered, but discounted on the basis that the false alarm rate is not affected by increasing the similarity between distracters and targets, and remains high when nonword stimuli are used. It is suggested, instead, that JB relies on a poorly focused memory description, which lacks item-specific detail but contains more general, low-level properties of the target items-these properties being held by many distracter items as well. This deficit is considered to arise because of damage to frontally mediated control processes involved in the selection of elements for memory encoding. An encoding deficit is supported by the fact that JB's false recognition is significantly reduced by orienting instructions, and is eliminated when his remote memory is subjected to recognition testing. In contrast, it is shown that manipulations at the level of retrieval (e.g. restricting the number of "old" responses) have little effect on his false recognition.

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Data sheet produced by the Iowa Department of Natural Resources is about different times of animals, insects, snakes, birds, fish, butterflies, etc. that can be found in Iowa.

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O objetivo deste artigo é buscar subsídios para uma melhor compreensão da situação atual de menor status acadêmico das licenciaturas nas universidades brasileiras e das conseqüentes dificuldades enfrentadas por esses cursos para implementação de mudanças significativas. São analisados resultados de uma investigação sócio-histórica realizada no curso de Ciências Biológicas da Universidade Federal de Minas Gerais - UFMG. A história desse campo, utilizada neste trabalho como um estudo de caso, revela pontos que poderão contribuir para um melhor entendimento dessa condição de menor prestígio acadêmico dos cursos de formação docente nas instituições de ensino superior brasileiras.

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The morphology and distribution of local-circuit neurons (interneurons) were examined, by calbindin D-28k and parvalbumin immunocytochemistry, in the frontal cortex (area 8) in two patients with frontal lobe dementia of non-Alzheimer type associated with classical amyotrophic lateral sclerosis (ALS), and in seven normal cases. The density of calbindin D-28k immunoreactive cells was dramatically reduced in ALS patients, but the density of parvalbumin-immunoreactive neurons was preserved. Decreased density of calbindin D-28k-immunoreactive neurons, which are mainly located in the upper cortical layers, may interfere with the normal processing of cortico-cortical connections, whereas integrity of parvalbumin-immunoreactive cells may be associated with the preservation of the major inhibitory intracortical circuits in patients with frontal lobe dementia.

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En agosto de 1978 iniciamos nuestras primeras excavaciones en este poblado, en el que en 1912, 1925 Y 1927 se habían hallado de forma casual diversos lotes de materiales de una cierta importancia, sobre todo el último, que ofreció cuatro páteras de tipo mesómphalos decoradas, diez vasos de tipo aqueménida y una copa, todo en plata, dado a conocer, el primero de ellos, por el Dr. Pere Bosch en el A.l.E.C. de 1913-14 y el resto por J. de C. Serra Ráfols en la revista Ampurias de 1941. Debido a la importancia de las piezas, a partir de 1929 se iniciaron los primeros sondeos y las primeras excavaciones en 1932, 1937 Y una gran campaña en 1942-43, a cargo de S. Vilaseca, Ll. Brull y J. de C. Serra Ráfols, a partir de las que se constató la existencia de un asentamiento ibérico y se descubrieron dos torres que flanqueaban el acceso al poblado, parte de la muralla y unos hábitats. De la última campaña se editó en 1949 una Memoria, no excesivamente completa, en la que los autores se limitaban a indicar la situación geográfica del yacimiento, los hallazgos fortuitos anteriores a su intervención, un breve repaso a los materiales de excavación y su opinión sobre la fecha de la destrucción del poblado, que situaron sobre el 218 a. de J. C. Indicamos que los materiales hallados en 1912 fueron depositados en el Museo Arqueológico de Tarragona, los de 1925 y 1927 en el de Barcelona, y los procedentes de las diversas campañas en el Museo Municipal de Reus. A partir del trabajo de 1949 nadie se volvió a ocupar de este magnífico poblado junto al Ebro, salvo algún intento de interpretación y estudio de las escenas, que grabadas a buril y sobredoradas, aparecen en una de las páteras halladas en 1927, y que han sido y son reproducidas en numerosas ocasiones, de manera que ellas, en el fondo, han sido las que han mantenido vivo el recuerdo de este yacimiento.

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Introduction: Survival of children born prematurely or with very low birth weight has increased dramatically, but the long term developmental outcome remains unknown. Many children have deficits in cognitive capacities, in particular involving executive domains and those disabilities are likely to involve a central nervous system deficit. To understand their neurostructural origin, we use DTI. Structurally segregated and functionally regions of the cerebral cortex are interconnected by a dense network of axonal pathways. We noninvasively map these pathways across cortical hemispheres and construct normalized structural connection matrices derived from DTI MR tractography. Group comparisons of brain connectivity reveal significant changes in fiber density in case of children with poor intrauterine grown and extremely premature children (gestational age<28 weeks at birth) compared to control subjects. This changes suggest a link between cortico-axonal pathways and the central nervous system deficit. Methods: Sixty premature born infants (5-6 years old) were scanned on clinical 3T scanner (Magnetom Trio, Siemens Medical Solutions, Erlangen, Germany) at two hospitals (HUG, Geneva and CHUV, Lausanne). For each subject, T1-weighted MPRAGE images (TR/TE=2500/2.91,TI=1100, resolution=1x1x1mm, matrix=256x154) and DTI images (30 directions, TR/TE=10200/107, in-plane resolution=1.8x1.8x2mm, 64 axial, matrix=112x112) were acquired. Parent(s) provided written consent on prior ethical board approval. The extraction of the Whole Brain Structural Connectivity Matrix was performed following (Cammoun, 2009 and Hagmann, 2008). The MPARGE images were registered using an affine registration to the non-weighted-DTI and WM-GM segmentation performed on it. In order to have equal anatomical localization among subjects, 66 cortical regions with anatomical landmarks were created using the curvature information, i.e. sulcus and gyrus (Cammoun et al, 2007; Fischl et al, 2004; Desikan et al, 2006) with freesurfer software (http://surfer.nmr.mgh.harvard.edu/). Tractography was performed in WM using an algorithm especially designed for DTI/DSI data (Hagmann et al., 2007) and both information were then combined in a matrix. Each row and column of the matrix corresponds to a particular ROI. Each cell of index (i,j) represents the fiber density of the bundle connecting the ROIs i and j. Subdividing each cortical region, we obtained 4 Connectivity Matrices of different resolution (33, 66, 125 and 250 ROI/hemisphere) for each subject . Subjects were sorted in 3 different groups, namely (1) control, (2) Intrauterine Growth Restriction (IUGR), (3) Extreme Prematurity (EP), depending on their gestational age, weight and percentile-weight score at birth. Group-to-group comparisons were performed between groups (1)-(2) and (1)-(3). The mean age at examination of the three groups were similar. Results: Quantitative analysis were performed between groups to determine fibers density differences. For each group, a mean connectivity matrix with 33ROI/hemisphere resolution was computed. On the other hand, for all matrix resolutions (33,66,125,250 ROI/hemisphere), the number of bundles were computed and averaged. As seen in figure 1, EP and IUGR subjects present an overall reduction of fibers density in both interhemispherical and intrahemispherical connections. This is given quantitatively in table 1. IUGR subjects presents a higher percentage of missing fiber bundles than EP when compared to control subjects (~16% against 11%). When comparing both groups to control subjects, for the EP subjects, the occipito-parietal regions seem less interhemispherically connected whilst the intrahemispherical networks present lack of fiber density in the lymbic system. Children born with IUGR, have similar reductions in interhemispherical connections than the EP. However, the cuneus and precuneus connections with the precentral and paracentral lobe are even lower than in the case of the EP. For the intrahemispherical connections the IUGR group preset a loss of fiber density between the deep gray matter structures (striatum) and the frontal and middlefrontal poles, connections typically involved in the control of executive functions. For the qualitative analysis, a t-test comparing number of bundles (p-value<0.05) gave some preliminary significant results (figure 2). Again, even if both IUGR and EP appear to have significantly less connections comparing to the control subjects, the IUGR cohort seems to present a higher lack of fiber density specially relying the cuneus, precuneus and parietal areas. In terms of fiber density, preliminary Wilcoxon tests seem to validate the hypothesis set by the previous analysis. Conclusions: The goal of this study was to determine the effect of extreme prematurity and poor intrauterine growth on neurostructural development at the age of 6 years-old. This data indicates that differences in connectivity may well be the basis for the neurostructural and neuropsychological deficit described in these populations in the absence of overt brain lesions (Inder TE, 2005; Borradori-Tolsa, 2004; Dubois, 2008). Indeed, we suggest that IUGR and prematurity leads to alteration of connectivity between brain structures, especially in occipito-parietal and frontal lobes for EP and frontal and middletemporal poles for IUGR. Overall, IUGR children have a higher loss of connectivity in the overall connectivity matrix than EP children. In both cases, the localized alteration of connectivity suggests a direct link between cortico-axonal pathways and the central nervous system deficit. Our next step is to link these connectivity alterations to the performance in executive function tests.

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Iowa State Capitol Interior Floors Map with cell phone audio information that can be used with a smartphone audio and video.

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Theodor W. Adorno construeix la modernitat com la fase final d'un procés d'emancipació que ha conduït justament al contrari del que es pretenia. L'alliberament del mite ha portat a una situació històrica en la qual l'encobriment ideològic del món és total. Això té conseqüències per a un pensament que vol ser crític, ja que haurà de trobar un lloc des d'on es pugui interpretar la història per tal de salvar la veritat d'un possible món diferent. En el moment de màxima ocultació ideològica i de màxim absurd -és conegut que Adorno es refereix al món contemporani com al temps després d'Auschwitz- Adorno intentarà entendre què ha passat amb aquest subjecte que s'ha preocupat excessivament per la seva identitat. Mitjançant l'aplicació del model psicoanalític d'interpretació a textos de Beckett i Kafka reconstruirà la història de l'emancipació fallida del subjecte modern. Amb aquestes interpretacions Adorno se situa no només molt a prop de la pràctica psicoanalítica, sinó també de la tradició hermenèutica clàssica.

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The Iowa State Capitol: A Self-Guided Tour with cell phone walking tour.

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Newborn neurons are generated in the adult hippocampus from a pool of self-renewing stem cells located in the subgranular zone (SGZ) of the dentate gyrus. Their activation, proliferation, and maturation depend on a host of environmental and cellular factors but, until recently, the contribution of local neuronal circuitry to this process was relatively unknown. In their recent publication, Song and colleagues have uncovered a novel circuit-based mechanism by which release of the neurotransmitter, γ-aminobutyric acid (GABA), from parvalbumin-expressing (PV) interneurons, can hold radial glia-like (RGL) stem cells of the adult SGZ in a quiescent state. This tonic GABAergic signal, dependent upon the activation of γ(2) subunit-containing GABA(A) receptors of RGL stem cells, can thus prevent their proliferation and subsequent maturation or return them to quiescence if previously activated. PV interneurons are thus capable of suppressing neurogenesis during periods of high network activity and facilitating neurogenesis when network activity is low.