999 resultados para Sistema de recompensa cerebral


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Disseminated nocardiosis of the central nervous system (CNS) has been rarely reported, especially in the immunocompetent patient. We report a case of cerebral and cervical intradural extramedullary nocardiosis likely to have been the result of disseminated spread from a pulmonary infective focus. Attempts at tissue biopsy and culture of the initial cerebral and pulmonary lesions both failed to yield the diagnosis. Interval development of a symptomatic intradural extramedullary cervical lesion resulted in open biopsy and an eventual diagnosis of nocardiosis was made. We highlight the diagnostic dilemma and rarity of spinal nocardial dissemination in an immunocompetent individual.

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Relatório de Investigação apresentado à Escola Superior de Educação de Paula Frassinetti para obtenção do grau de Mestre em Educação Pré-Escolar e Ensino do 1º CEB.

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El ácido lisofosfatídico (LPA) es un fosfolípido sencillo con propiedades de señalización extracelular mediadas por receptores de membrana específicos acoplados a proteínas G. Actualmente se conocen hasta 6 tipos de receptores diferentes para el LPA. El receptor LPA1 se expresa en la zona neurogénica del cerebro en desarrollo, en la zona ventricular (VZ), lo que sugiere su implicación en la neurogénesis. A pesar de los numerosos estudios farmacológicos que han aportado datos de los efectos del LPA en el sistema nervioso central (SNC) utilizando modelos in vitro, no es sino hasta que se dispuso de animales carentes del receptor, cuando se avanzó en el estudio de la función específica del receptor. Los primeros ratones obtenidos que permitían el estudio de pérdida de función del receptor LPA1 mostraron una alta mortalidad perinatal pero abrían una puerta excelente a nuevos estudios de caracterización del SNC en ausencia de vías específicas de señalización por LPA. En el presente trabajo se muestran resultados que demuestran una función destacada del receptor LPA1 en los precursores neuronales corticales durante el desarrollo cerebral, resultantes del análisis de la neurogénesis en una variante, que hemos venido a denominar Málaga, de un ratón nulo para-LPA1. Esta variante surge de forma espontánea durante la expansión de la colonia original y porta un fenotipo con defectos observables en el SNC, a la vez que muestra una viabilidad perinatal casi completa, lo que ha permitido su caracterización. Nuestros resultados muestran alteraciones significativas en la neurogénesis cortical embrionaria, en el patrón proliferativo de la zona ventricular, afectando al tipo de división y la posterior diferenciación, con expresión de marcadores neuronales de forma prematura en la capa cortical y alteración de la expresión de factores de transcripción. Estos defectos de la neurogénesis en ausencia de la vía de señalización por LPA1 se asocian con defectos en el patrón migratorio neuronal, indicativos de alteraciones de tipo estructural y funcional, y que generan, en última instancia, una reducción del grosor de la pared cortical y del número de neuronas en diferentes capas corticales, especialmente las profundas donde se detecta, además, un nivel inusualmente mayor de apoptosis. Los resultados que mostramos en esta memoria reflejan, con ello, la necesidad del receptor LPA1 para el desarrollo normal cerebral y acentúan el importante papel que el modelo de animal nulo para LPA1 de la variedad Málaga ha representado para el estudio de la señalización mediada por este receptor. A la fecha actual, el uso de este ratón ha permitido un avance muy significativo en el campo y sigue siendo objeto de estudio por nuestro grupo de investigación y por diferentes colaboradores a nivel nacional e internacional.

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El objetivo de este Trabajo de Fin de Grado es la creación de un software para la comunicación de personas con discapacidad exclusivamente motriz, incluyendo el habla, pero sin tener afectada la cognición; concretamente va dirigido a un niño que padece una parálisis cerebral. Dicho software se ha desarrollado en dos programas separados. El primero es un software de seguimiento de pupila basado en la tecnología de EyeTracking, para lo que se usa un ratón de mirada proporcionado por un programa ya existente. La aportación en este apartado ha sido crear una interfaz, como capa superior, mediante botones que ejecutan las acciones correspondientes a seleccionar el método de comunicación y las opciones correspondientes a cada método que ofrece el sistema. Nuestro niño, Moisés, sufre disponía, lo que implica fluctuación ene el tono muscular, unas veces hipertónico y otras hipotónico en distintas partes de su cuerpo, afectándole a la sujeción de la cabeza. Por ese motivo se ha desarrollado un segundo programa que funciona con ratón y teclado, al cual se le ha añadido un pulsador. Incluye un menú para seleccionar distintas formas de comunicación. Las opciones de este menú se le ofrecen al usuario de forma secuencial ya que solo podrá comunicarse con el sistemas mediante clicks de ratón o pulsaciones de teclado. En España la empresa Vía Libre de la fundación ONCE vende materiales ortopédicos y de comunicación, todos con licencia de uso, como el usado por Stephen Hawking, no asequibles a familias que ya tienen gastos en sillas, adaptadores, y material ortopédico. Este segundo programa ha sido probado y modificado según las principales necesidades de comunicación de Moisés, es de código abierto y puede ser descargable desde https://sourceforge.net/p/clickspeak/

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Se desconocen los efectos del entrenamiento interválico de alta intesidad (HIIT) sobre el flujo sanguíneo cerebral (FSC) y la oxigenación cerebral. Por ello reclutamos a 20 voluntarios que realizaron una sesión de HIIT (4 test de Wingate con recuperaciones de 4 minutos). Se midió la oxigenación del lóbulo frontal (OLF) y el Vastus lateralis (VL) a través de espectrofotometría cercana a los infrarrojos (NIRS). También se registró la velocidad de la sangre en las arterias cerebrales medias (vACM) mediante Doppler. La vACM disminuyó entre un 5 y 10 % en el primer esprint. En los siguientes esprints se redujo aún más. La vACM descendió en cada esprint coincidiendo con la disminución de la presión tele-espiratoria de dióxido de carbono (PETCO2) y con valores superiores de ventilación pulmonar (VE). Al interrumpirse el pedaleo se redujo bruscamente la vACM. Sin embargo, la OLF se mantuvo estable en el primer esprint sólo reduciéndose ligeramente durante el segundo y tercer Wingate (el cuarto fue similar al tercero). Este estudio muestra que la vACM disminuye durante los ejercicios de esprint, posiblemente debido a la hipocapnia. La reducción de la vACM no ejerce efectos funcionales ni relevantes sobre la oxigenación cerebral, gracias al ajuste de la conductancia vascular a través de los mecanismos de autoregulación, sin que parezca afectar negativamente al rendimiento.

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Introducción El modelo desequilibrio esfuerzo – recompensa es un importante predictor de estrés laboral y por consiguiente de alteraciones en la salud cardiovascular, por ello en los últimos 10 años se ha encontrado importante evidencia y estudios respecto al tema; las publicaciones científicas se han enfocado en establecer relación entre factores psicosociales en el trabajo y consecuencias sobre la salud dándole relevancia a los factores biológicos principalmente los cardiovasculares. Objetivo Se evaluó la evidencia entre el desequilibrio esfuerzo recompensa y las alteraciones cardiovasculares en los trabajadores. Metodología Se realizó una revisión de la literatura en principales bases de datos como son pubmed, ovid y revistas electrónicas, en idioma inglés – español durante los últimos 10 años, usando palabras de búsqueda como desequilibrio esfuerzo recompensa, alteraciones cardiovasculares, trabajadores. Resultados Se encontró fuerte evidencia entre el desequilibrio esfuerzo recompensa con enfermedades cardiovasculares en los trabajadores, principalmente con las alteraciones en la tensión arterial en los trabajadores más expuestos, al igual que una relación mayor en mujeres que hombres que aumentaba con la edad. Se evidenció que después de haber sufrido un evento coronario agudo los trabajadores que continuaban expuestos a altas cargas de tensión laboral eran más propensos a desarrollar enfermedad coronaria recurrente. El sobrecompromiso (PR 1,91, IC 95% 1,35-2,69) y el desequilibrio esfuerzo recompensa (PR 2,47, IC 95% 1,62-3,75) se asociaron con riesgo de hipertensión arterial después de ajustar las variables de confusión. Se encontró asociación entre el desequilibrio esfuerzo recompensa e hipertensión arterial (OR 1,53-3,71 IC 95%). La ERI alta y la baja recompensa se asociaron con enfermedad coronaria recurrente (RR = 1,75, intervalo de confianza del 95% [IC] = 0,99 - 3,08 y HR = 1,77, IC del 95% = 1,16 - 2,71). Hubo una interacción de género que mostró efectos más fuertes entre las mujeres (HR respectivamente ajustadas para ERI alta y baja recompensa: HR = 3,95, IC del 95% = 0,93- 16,79, y HR = 9,53, IC del 95% = 1,15- 78,68). Conclusiones Se encontró una relación entre el desequilibrio esfuerzo recompensa con enfermedades cardiovasculares, principalmente con las alteraciones en la tensión arterial y eventos coronarios

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Background: In pathological situations, such as acute myocardial infarction, disorders of motility of the proximal gut can trigger symptoms like nausea and vomiting. Acute myocardial infarction delays gastric emptying (GE) of liquid in rats. Objective: Investigate the involvement of the vagus nerve, α 1-adrenoceptors, central nervous system GABAB receptors and also participation of paraventricular nucleus (PVN) of the hypothalamus in GE and gastric compliance (GC) in infarcted rats. Methods: Wistar rats, N = 8-15 in each group, were divided as INF group and sham (SH) group and subdivided. The infarction was performed through ligation of the left anterior descending coronary artery. GC was estimated with pressure-volume curves. Vagotomy was performed by sectioning the dorsal and ventral branches. To verify the action of GABAB receptors, baclofen was injected via icv (intracerebroventricular). Intravenous prazosin was used to produce chemical sympathectomy. The lesion in the PVN of the hypothalamus was performed using a 1mA/10s electrical current and GE was determined by measuring the percentage of gastric retention (% GR) of a saline meal. Results: No significant differences were observed regarding GC between groups; vagotomy significantly reduced % GR in INF group; icv treatment with baclofen significantly reduced %GR. GABAB receptors were not conclusively involved in delaying GE; intravenous treatment with prazosin significantly reduced GR% in INF group. PVN lesion abolished the effect of myocardial infarction on GE. Conclusion: Gastric emptying of liquids induced through acute myocardial infarction in rats showed the involvement of the vagus nerve, alpha1- adrenergic receptors and PVN.Fundamento: Distúrbios da motilidade do intestino proximal no infarto agudo do miocárdio podem desencadear sintomas digestivos como náuseas e vômitos. O infarto do miocárdio ocasiona retardo do esvaziamento gástrico (EG) de líquido em ratos. Objetivo: Investigar se existe a influência do nervo vago (VGX), adrenoreceptores α-1, receptores GABAB do sistema nervoso central e participação do núcleo paraventricular (NPV) do hipotálamo no esvaziamento gástrico (EG) e complacência gástrica (CG) em ratos infartados. Métodos: Ratos Wistar (n = 8-15) foram divididos em: grupo infarto (INF), sham (SH) e subdivididos. O infarto foi realizado por ligadura da artéria coronária descendente anterior. A complacência gástrica foi estimada com curvas pressão-volume. Realizada vagotomia por secção dos ramos dorsal e ventral. Para verificar a ação dos receptores GABAB foi injetado baclofeno por via intra ventrículo-cerebral. Simpatectomia química foi realizada com prazosina intravenosa (iv), e na lesão do núcleo paraventricular do hipotálamo foi utilizada corrente elétrica de 1mA/10s, com esvaziamento gástrico determinado por medição da retenção gástrica (% RG) de uma refeição salina. Resultados: Não houve diferença significativa na CG. A vagotomia (VGX) reduziu significativamente a %RG; no grupo INF, o tratamento intra ventrículo-cerebral (ivc) com baclofeno reduziu significativamente a % RG; não houve conclusivamente envolvimento dos receptores GABAB em retardar o EG; o tratamento intravenoso com prazosina reduziu significativamente a %RG no grupo INF. A lesão do NPV aboliu o efeito do infarto do miocárdio no EG. Conclusão: O nervo vago, receptores α-adrenérgicos e núcleo paraventricular estão envolvidos no retardo do esvaziamento gástrico no infarto agudo do miocárdio em ratos.

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Machado-Joseph disease (MJD/SCA3) is the most frequent spinocerebellar ataxia, characterized by brainstem, basal ganglia and cerebellar damage. Few magnetic resonance imaging based studies have investigated damage in the cerebral cortex. The objective was to determine whether patients with MJD/SCA3 have cerebral cortex atrophy, to identify regions more susceptible to damage and to look for the clinical and neuropsychological correlates of such lesions. Forty-nine patients with MJD/SCA3 (mean age 47.7 ± 13.0 years, 27 men) and 49 matched healthy controls were enrolled. All subjects underwent magnetic resonance imaging scans in a 3 T device, and three-dimensional T1 images were used for volumetric analyses. Measurement of cortical thickness and volume was performed using the FreeSurfer software. Groups were compared using ancova with age, gender and estimated intracranial volume as covariates, and a general linear model was used to assess correlations between atrophy and clinical variables. Mean CAG expansion, Scale for Assessment and Rating of Ataxia (SARA) score and age at onset were 72.1 ± 4.2, 14.7 ± 7.3 and 37.5 ± 12.5 years, respectively. The main findings were (i) bilateral paracentral cortex atrophy, as well as the caudal middle frontal gyrus, superior and transverse temporal gyri, and lateral occipital cortex in the left hemisphere and supramarginal gyrus in the right hemisphere; (ii) volumetric reduction of basal ganglia and hippocampi; (iii) a significant correlation between SARA and brainstem and precentral gyrus atrophy. Furthermore, some of the affected cortical regions showed significant correlations with neuropsychological data. Patients with MJD/SCA3 have widespread cortical and subcortical atrophy. These structural findings correlate with clinical manifestations of the disease, which support the concept that cognitive/motor impairment and cerebral damage are related in disease.

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Neurogenic pulmonary edema is a rare and serious complication in patients with head injury. It also may develop after a variety of cerebral insults such as subarachnoid hemorrhage, brain tumors and after epileptic seizures. Thirty six patients with severe head injury and four patients with cerebrovascular insults treated in Intensive Care Unit of HC-UNICAMP from January to September 1995 were evaluated. In this period there were two patients with neurogenic pulmonary edema, one with head injury and other with intracerebral hemorrhage. Diagnosis was made by rapid onset of pulmonary edema, severe hypoxemia, decrease of pulmonary complacence and diffuse pulmonary infiltrations, without previous history of tracheal aspiration or any other risk factor for developement of adult respiratory distress syndrom. In the first case, with severe head trauma, neurogenic pulmonary edema was diagnosed at admission one hour after trauma, associated with severe systemic inflammatory reaction, and good outcome in three days. The second case, with hemorragic vascular insult, developed neurogenic pulmonary edema the fourth day after drenage of intracerebral hematom and died.

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Multi-element analyses of sediment samples from the Santos-Cubatão Estuarine System were carried out to investigate the spatial and seasonal variability of trace-element concentrations. The study area contains a rich mangrove ecosystem that is a habitat for tens of thousands of resident and migratory birds, some of them endangered globally. Enrichments of metals in fine-grained surface sediments are, in decreasing order, Hg, Mn, La, Ca, Sr, Cd, Zn, Pb, Ba, Cu, Cr, Fe, Nb, Y, Ni and Ga, relative to pre-industrial background levels. The maximum enrichment ranged from 49 (Hg) to 3.1 (Ga). Mercury concentrations were greater in the Cubatão river than in other sites, while the other elements showed greater concentrations in the Morrão river. Concentrations of Mn were significantly greater in winter and autumn than in summer and spring. However, other elements (e.g. Cd and Pb) showed the opposite, with greater concentrations in summer and spring. This study suggests that seasonal changes in physical and chemical conditions may affect the degree of sediment enrichment and therefore make the assessment of contamination difficult. Consequently, these processes need to be considered when assessing water quality and the potential contamination of biota.

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A solid-phase in-line extraction system for water samples containing low levels of emerging contaminants is described. The system was specially developed for large volume samples (up to 4 L) using commercial solid-phase extraction (SPE) cartridges. Four sets containing PTFE-made connectors, brass adapters and ball valves were used to fit SPE cartridges and sample bottles to a 4-port manifold attached to a 20 L carboy. A lab-made vacuum device was connected to the manifold cap. The apparatus is robust and less expensive than the typical available system. Its also provides less experimental handling, avoiding cross contamination and sample losses.

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The difficulty in adapting European dairy cows breeds in Brazil affect considerably the milk production sector. Brazilian climatic conditions are not totally favorable and the development of new tecnologies is needed for the animals express their genetic potential, as well as their best feed conversion. An economical analysis of the applied investment in the free-stall climatization equipment in dairy housing, for estimating studies related to profit, possibility of return investment as well as time for this return is necessary. The objective of this research was to evaluate the influence of climatization investment in the milk production process and analyze the economical aspect of this investment. There were used 470 high productive dairy cows with genetic and morphologic homogeneous characteristics, and analyzed in two similar periods. Investment calculations were done using Excell®. The results were satisfactory and the invested capital was proved to return to the producer in a short term, 57 days.

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In the last few years the sugar-cane mechanical harvested area has increased, especially in regions with appropriated slop. The use of this technology brings some inconveniences, such as, the increase in the percentage of extraneous matter, which causes the reduction of technological quality of the raw material, and losses in the field. Extraneous matter (trash) is composed of tops and leaves in major percentage, plus soil and roots, and eventually some metal parts. In the green cane harvest system the percentage of extraneous matter has a tendency to increase due to the great amount of vegetal matter to be processed. The increase in the blower fan speed to reduce the amount of extraneous matter can lead to an unacceptable economic level of raw material losses. The main objective of this work was, using a cane loss monitor, to evaluate and quantify the amount of visible losses of sugar cane through the primary extractor at two different fan speeds. Afterwards these losses were related to the harvester cleaning efficiency. The piezoelectric transducer shows a reasonable sensibility. The results show that the cleaning efficiency in the primary extractor (85% mean), the cane losses (between 5.68% and 2.15%) and fan speed are interrelated. The total losses and specially splinters (between 3.19% and 0.91%), showed a significant difference among the treatments.

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One of the problems found in mechanical harvest of sugar cane is the lack of synchronism between the harvest machine and the infield wagon, causing crop losses as well as operational capacity. The objective of the present research was to design a system capable of helping to synchronize the sugar cane harvest machine with the wagon. The communication between tractor and harvest machine is wireless. Two ultrasound sensors coupled to the elevator and a microprocessor manage such information, generating a correct synchronization among the machines. The system was tested in laboratory and on field performing its function adequately, maintaining the two machines in synchronization, indicating and alerting the operators their relative positions. The developed system reduced the sugar cane lost in 60 kg ha-1 comparing to the harvest with the system turned off.

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The MINUS system was developed as a minimally invasive procedure that uses a diaphyseal cephalic extramedullary implant for the treatment of transtrochanteral fractures of the femur in elderly patients. The implant consists of a sliding screw coupled to a plate adapted to the minimally invasive technique. The surgical access is approximately three centimeters in length located on the lateral surface of the hip, below the projection of the small trochanter. A perfectly adapted instrument was used for the procedure, which also requires the use of an image intensifier, reducing surgery time and rate of bleeding. The objective of this study is to present a new instrument and implant, developed specifically for treatment with the minimally invasive technique, reducing the length of the conventional surgical access from 10 to three centimetres. This new implant was given the commercial name of MINUS System.