973 resultados para Magistério primário


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Mirror therapy (MT) is being used as a rehabilitation tool in various diseases, including stroke. Although some studies have shown its effectiveness, little is known about neural mechanisms that underlie the rehabilitation process. Therefore, this study aimed at assessing cortical neuromodulation after a single MT intervention in ischemic stroke survivors, by means of by functional Magnetic Resonance Imaging (fMRI) and Transcranial Magnetic Stimulation (TMS). Fifteen patients participated in a single thirty minutes MT session. fMRI data was analyzed bilaterally in the following Regions of Interest (ROI): Supplementary Motor Area (SMA), Premotor cortex (PMC), Primary Motor cortex (M1), Primary Sensory cortex (S1) and Cerebellum. In each ROI, changes in the percentage of occupation and beta values were computed. Group fMRI data showed a significant decreased in the percentage of occupation in PMC and cerebellum, contralateral to the affected hand (p <0.05). Significant increase in beta values was observed in the following contralateral motor areas: SMA, Cerebellum, PMC and M1 (p<0,005). Moreover, a significant decrease was observed in the following ipsilateral motor areas: PMC and M1 (p <0,001). In S1 a bilateral significant decrease (p<0.0005) was observed.TMS consisted of the analysis of Motor Evoked Potential (MEP) of M1 hotspot. A significant increase in the amplitude of the MEP was observed after therapy in the group (p<0,0001) and individually in 4 patients (p <0.05). Altogether, our results imply that single MT intervention is already capable of promoting changes in neurobiological markers toward patterns observed in healthy subjects. Furthermore, the contralateral hemisphere motor areas changes are opposite to the ones in the ipsilateral side, suggesting an increase system homeostasis.

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Desde os descobrimentos pioneiros de Hubel e Wiesel acumulou-se uma vasta literatura descrevendo as respostas neuronais do córtex visual primário (V1) a diferentes estímulos visuais. Estes estímulos consistem principalmente em barras em movimento, pontos ou grades, que são úteis para explorar as respostas dentro do campo receptivo clássico (CRF do inglês classical receptive field) a características básicas dos estímulos visuais como a orientação, direção de movimento, contraste, entre outras. Entretanto, nas últimas duas décadas, tornou-se cada vez mais evidente que a atividade de neurônios em V1 pode ser modulada por estímulos fora do CRF. Desta forma, áreas visuais primárias poderiam estar envolvidas em funções visuais mais complexas como, por exemplo, a separação de um objeto ou figura do seu fundo (segregação figura-fundo) e assume-se que as conexões intrínsecas de longo alcance em V1, assim como as conexões de áreas visuais superiores, estão ativamente envolvidas neste processo. Sua possível função foi inferida a partir da análise das variações das respostas induzidas por um estímulo localizado fora do CRF de neurônios individuais. Mesmo sendo muito provável que estas conexões tenham também um impacto tanto na atividade conjunta de neurônios envolvidos no processamento da figura quanto no potencial de campo, estas questões permanecem pouco estudadas. Visando examinar a modulação do contexto visual nessas atividades, coletamos potenciais de ação e potenciais de campo em paralelo de até 48 eletrodos implantados na área visual primária de gatos anestesiados. Estimulamos com grades compostas e cenas naturais, focando-nos na atividade de neurônios cujo CRF estava situado na figura. Da mesma forma, visando examinar a influência das conexões laterais, o sinal proveniente da área visual isotópica e contralateral foi removido através da desativação reversível por resfriamento. Fizemos isso devido a: i) as conexões laterais intrínsecas não podem ser facilmente manipuladas sem afetar diretamente os sinais que estão sendo medidos, ii) as conexões inter-hemisféricas compartilham as principais características anatômicas com a rede lateral intrínseca e podem ser vistas como uma continuação funcional das mesmas entre os dois hemisférios e iii) o resfriamento desativa as conexões de forma causal e reversível, silenciando temporariamente seu sinal, permitindo conclusões diretas a respeito da sua contribuição. Nossos resultados demonstram que o mecanismo de segmentação figurafundo se reflete nas taxas de disparo de neurônios individuais, assim como na potência do potencial de campo e na relação entre sua fase e os padrões de disparo produzidos pela população. Além disso, as conexões laterais inter-hemisféricas modulam estas variáveis dependendo da estimulação feita fora do CRF. Observamos também uma influência deste circuito lateral na coerência entre potenciais de campo entre eletrodos distantes. Em conclusão, nossos resultados dão suporte à ideia de um mecanismo complexo de segmentação figura-fundo atuando desde as áreas visuais primárias em diferentes escalas de frequência. Esse mecanismo parece envolver grupos de neurônios ativos sincronicamente e dependentes da fase do potencial de campo. Nossos resultados também são compatíveis com a hipótese que conexões laterais de longo alcance também fazem parte deste mecanismo

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The use of non-human primates in scientific research has contributed significantly to the biomedical area and, in the case of Callithrix jacchus, has provided important evidence on physiological mechanisms that help explain its biology, making the species a valuable experimental model in different pathologies. However, raising non-human primates in captivity for long periods of time is accompanied by behavioral disorders and chronic diseases, as well as progressive weight loss in most of the animals. The Primatology Center of the Universidade Federal do Rio Grande do Norte (UFRN) has housed a colony of C. jacchus for nearly 30 years and during this period these animals have been weighed systematically to detect possible alterations in their clinical conditions. This procedure has generated a volume of data on the weight of animals at different age ranges. These data are of great importance in the study of this variable from different perspectives. Accordingly, this paper presents three studies using weight data collected over 15 years (1985-2000) as a way of verifying the health status and development of the animals. The first study produced the first article, which describes the histopathological findings of animals with probable diagnosis of permanent wasting marmoset syndrome (WMS). All the animals were carriers of trematode parasites (Platynosomum spp) and had obstruction in the hepatobiliary system; it is suggested that this agent is one of the etiological factors of the syndrome. In the second article, the analysis focused on comparing environmental profile and cortisol levels between the animals with normal weight curve evolution and those with WMS. We observed a marked decrease in locomotion, increased use of lower cage extracts and hypocortisolemia. The latter is likely associated to an adaptation of the mechanisms that make up the hypothalamus-hypophysis-adrenal axis, as observed in other mammals under conditions of chronic malnutrition. Finally, in the third study, the animals with weight alterations were excluded from the sample and, using computational tools (K-means and SOM) in a non-supervised way, we suggest found new ontogenetic development classes for C. jacchus. These were redimensioned from five to eight classes: infant I, infant II, infant III, juvenile I, juvenile II, sub-adult, young adult and elderly adult, in order to provide a more suitable classification for more detailed studies that require better control over the animal development

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Immediate-early genes (IEGs) expression has been widely used as a valuable tool to investigate brain areas activated by specific stimuli. Studies of natural vocalizations, specially in songbirds, have largely benefited from this tool. Here we used IEGs expression to investigate brain areas activated by the hearing of conspecific common marmoset (Callithrix jacchus) vocalizations and/or utterance of antiphonal vocalizations. Nine adult male common marmosets were housed in sound-attenuating cages. Six animals were stimulated with playbacks of freely recorded natural long distance vocalizations (phee calls and twitters; 45 min. total duration). Three of them vocalized in response (O/V group) and three did not (O/n group). The control group (C) was composed by the remaining animals, which neither heard the playbacks nor spontaneously vocalized. After one hour of the stimulation onset (or no stimulation, in the case of the C group), animals were perfused with 0,9% phosphate-saline buffer and 4% paraformaldehyde. The tissue was coronally sectioned at 20 micro meter in a cryostat and submitted to immunohistochemistry for the IEGs egr-1 and c-fos. Marked immunoreactivity was observed in the auditory cortex of O/V and O/n subjects and in the anterior cingulate cortex, the dorsomedial prefrontal cortex and the ventrolateral prefrontal cortex of O/V subjects. In this study, brain areas activated by vocalizations of common marmosets were investigated using IEGs expression for the first time. Our results with the egr-1 gene indicate that potential plastic phenomena occur in areas related to hearing and uttering conspecific vocalizations.

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The retinal projections in mammals usually reach, classically, three major functional systems: the primary visual system, the accessory optic system, and the circadian timing system. But the retinal projections also reach areas classically considered non-visual, one of which groups the neurons of the zona incerta (ZI), target this study. The primary visual system includes thalamic lateral geniculate complex is formed by the dorsal lateral geniculate nucleus, intergeniculate leaflet and the ventral lateral geniculate nucleus and other Components. The accessory optic system is composed of the small nuclei: nuclei terminal dorsal, lateral, medial and the interstitial nucleus of the superior posterior fasciculus. These nuclei are involved in visuo-motor activities. The circadian timing system is comprised of the suprachiasmatic nucleus of the hypothalamus, that act as master circadian pacemaker, entraining pathways and efferents pathways to the efectors, and the intergeniculate leaflet, that seems to act as a modulator of the pacemaker. The retinal projections too reach classically considered non-visual areas, including the zona incerta. This region is localized in the ventral thalamus and has been implicated in various functional properties including nociceptive and somatosensory processing, motor response, sociosexual behaviour, feeding and drinking, in symptoms of neurodegenerative diseases, arousal and attention. It also displays connection with several areas of central nervous system. The aim of this study was characterize the retinal projection in the zona incerta of Callithrix jacchus (sagüi), a primate of the New World through the anterograde axonal transport of the cholera toxin subunit b and analyze the citoarchicteture using Nissl and NeuN, and neurochemical substances such as serotonin, GABA, VIP, VP, GFAP and binding-calcium proteins. The zona incerta showed a different division of the literature in citoarquitetura, both by means of Nissl as neurochemical by NeuN, with a subdivision ventrolateral and dorsomedial. The neurochemical to the other substances corroborate with this subdivision. The GFAP was almost completely negative for the zona incerta, result non evidenced in previous studies yet. The 16 retinal projection in sagüi, unlike other primates and rodents, reached the caudal portion only. This work helps to make further studies are conducted based on this subdivision and the localization of the neurochemical substances associated with possible behaviors that the zona incerta is involved

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Most cochlear implant (CI) users, who suffer from post lingual hearing loss, are able to perceive sounds and comprehend speech after the implant. The prediction of maximal benefit over time, with the use of CI, can be useful for counseling patients about their expectations in using the new device. The measurement of satisfaction should be of primary interest in medical intervention, as the results may be used for intervention feedback. The purpose of this study is to analyze auditory performance of CI over time, as well as to evaluate users‟ satisfaction. Therefore two types of study designs were employed: a) retrospective cohort study with the analysis of medical records from 59 subjects about auditory performance before and after surgery. Results were submitted to the Kaplan -Meier estimator of cumulative probability and compared to prognostic factors of auditory performance using the logrank test. b) A sectional study design was conducted to evaluate the satisfaction of 51 subjects. The instrument consists of two specific questionnaires: Satisfaction with Amplification in Daily Life SADL and International Outcome Inventory Cochlear Implant IOI- CI. Results show statistical significant differences (p<0,001) in auditory performance before and after CI. The majority obtained satisfactory results of CI use during the first six months. Logrank tests does not indicate significant correlation between the analyzed covariates and the time in which adequate speech perception occurs. SADL e IOI-CI questionnaires indicate that most of the CI users are satisfied with their devices. The SADL detected a 27, 5% insatisfaction amongst CI users in relation to services and costs involved with the CI. The results of the IOI show 4% of insatisfaction with the use of CI and the social environment. In conclusion CI is capable to rehabilitate social auditory function in a short period of time and CI users demonstrate satisfaction with auditory, social and psychological gain offered through CI device

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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RACIONAL: O carcinoma de pequenas células primário do esôfago é tumor raro, agressivo, morfologicamente indistinguível de seu correspondente no pulmão. OBJETIVO: Apresentar os aspectos clínico-patológicos de dois pacientes com carcinoma de pequenas células do esôfago. RELATO DE CASOS: Paciente 1: masculino, 56 anos com disfagia progressiva há seis meses e emagrecimento, com antecedentes de tabagismo e etilismo. A endoscopia mostrou lesão vegetante dos 30 aos 40 cm da arcada dentária superior e o exame anatomopatológico, diagnosticou neoplasia maligna indiferenciada de pequenas células com marcadores imunoistoquímicos positivos para cromogranina e sinaptofisina, caracterizando a linhagem neuroendócrina da neoplasia. Após dois ciclos de quimioterapia (cisplatina e etoposide) associada à radioterapia ele apresentou remissão da disfagia. Paciente 2: masculino, 55 anos, com queixas de pirose, disfagia, rouquidão há seis meses, com emagrecimento de 10 kg no período. A endoscopia mostrou lesão vegetante à 30 cm da arcada dentária superior, obstrutiva. O exame anatomopatológico revelou carcinoma de pequenas células, com os mesmos marcadores imunoistoquímicos positivos para linhagem neuroendócrina. Tomografia computadorizada mostrou metástases hepáticas. Frente ao estadio avançado da doença optou-se pela indicação de gastrostomia. O paciente desenvolveu pneumonia e faleceu dois meses após o diagnóstico. CONCLUSÃO: A evolução dos portadores de carcinoma de pequenas células do esôfago depende do estadiamento da doença e apesar da alta agressividade biológica, este tumor apresenta boa resposta à quimioterapia associada à radioterapia.

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This study is about the primary stakeholder management - the resident community, given its participation and support for the development of tourism in touristic destinations. It has as a general aim to analyze the factors that are capable to influence the residents‟ support to the development of religious tourism in Santa Cruz, RN, and the existing interrelationships between factors. In order to achieve this objective, it was necessary to use exploratory and descriptive research, followed by a quantitative approach through questionnaires with 422 residents of Santa Cruz -RN. The study was based on the variables relationship model proposed by Nunkoo and Ramkissoon (2012), it was also used the technique of Structural Equation Modeling - SEM, aiming to explain the relationships between the constructs studied. The results found on the survey suggest that the more residents realize the benefits generated by tourism, as well as trust in government actors in charge of tourism development, the more there will be a propensity to support the development of religious tourism. This result is similar to the one found in the study of Nunkoo and Ramkissoon (2012). We conclude that the structural model that best represents the reality of Santa Cruz -RN is composed of the factors: benefits, costs, and confidence in governmental actors, which are able to influence the support of Santa Cruz‟s residents for the development of religious tourism. It is also noteworthy that it was found a highly significant connection between the factors benefits perceived from tourism and confidence in governmental actors and between both of them, the political support for tourism

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The diversity of fish species from South America has been affected by various anthropogenic practices. Some studies have reported the influence that illegal transferring or introduction of exotic species have on the trophic webs of continental lakes. The loss of diversity on fish populations and consequent impacts on fishery are commonly evidenced in these cases. The Brazilian Northeast has ponds for which exotic Amazonian species were transferred as Extremoz Lake. These environments serve as study models for comparison and investigation about the possible impacts of these introductions. We tested the hypothesis that loss of species that this trend can be related with the insertion of the genus Cichla, commonly documented as top predator in its endemic environment. Possible structural causes that interfere in other processes such as migration were also investigated. Thus, the local ecological knowledge of fishermen and a current ecotrophic model were used. We took samples of phytoplankton, zooplankton and fishes during two annual cycles. Concurrently, we made interviews with the fishing community. In fact, there are relations between the loss of fish and the insertion of peacock bass in Extremoz Lake. However, Cichla kelberi was not indicated as primary factor to explain fish species decline. The construction of bridges located in the Rio Doce was main factor for respondents and what explains loss of species. The migration of saltwater fish and / or from the river to Extremoz Lake is hindered by the unsuitability of the crossing-streams that are under these structures. According to the ecotrophic model Hoplias malabaricus was considered key-species and Cichla kelberi top predator. This last trend was similarly noticed in the stomach and local ecological knowledge of fishermen analysis. Overfishing simulations to Cichla kelberi resulted that only raising its captures in 200%, other native species would increase their biomass values only 15 to 30% (in 6 years).The negative effects of the alien species introduction without prior studies and lack of investments in appropriating these constructions to the needs of the fish fauna structures seem to act simultaneously. Both are causing the decline of fish species richness and consequent local artisanal fishery collapse

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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OBJETIVO: Comparar duas técnicas de tratamento da hérnia incisional em coelhos utilizando a tela de polipropileno apoiando um reforço peritônio - aponeurótico ou suturada nas bordas do anel herniário 'em ponte . MÉTODOS: Foram operados 60 coelhos para a produção de hérnia incisional, em uma incisão mediana de 4 centímetros. Após 30 dias, metade dos animais foram operados com o fechamento primário da parede, com colocação de uma tela de polipropileno apoiando o reforço e a outra metade dos animais com a colocação da tela suturada nas bordas do anel herniárioem ponte . Os animais foram avaliados com 30 (M1), 60 (M2)e 90 (M3) dias de pós-operatório. Os parâmetros analisados foram a evolução clínica, análise da força de ruptura da cicatriz, estudo macroscópico, análise microscópica e morfométrica. RESULTADOS: Não foram observadas diferenças significantes com relação a força de ruptura e estudos histológicos nos dois grupos e vários momentos estudados. Não houve diferença estatística com relação às complicações, embora os animais que receberam a telaem ponte tiveram aderências mais firmes e intensas à parede abdominal. CONCLUSÕES: As duas técnicas utilizadas para correção da hérnia incisional em coelhos não mostraram diferenças significantes quanto a força de ruptura, análise histológica e morfométrica. O número de complicações foi semelhante, porém a aderência de órgãos da cavidade abdominal à área de cicatriz foi muito mais intensa no grupo em que a tela foi colocadaem ponte .

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The separation methods are reduced applications as a result of the operational costs, the low output and the long time to separate the uids. But, these treatment methods are important because of the need for extraction of unwanted contaminants in the oil production. The water and the concentration of oil in water should be minimal (around 40 to 20 ppm) in order to take it to the sea. Because of the need of primary treatment, the objective of this project is to study and implement algorithms for identification of polynomial NARX (Nonlinear Auto-Regressive with Exogenous Input) models in closed loop, implement a structural identification, and compare strategies using PI control and updated on-line NARX predictive models on a combination of three-phase separator in series with three hydro cyclones batteries. The main goal of this project is to: obtain an optimized process of phase separation that will regulate the system, even in the presence of oil gushes; Show that it is possible to get optimized tunings for controllers analyzing the mesh as a whole, and evaluate and compare the strategies of PI and predictive control applied to the process. To accomplish these goals a simulator was used to represent the three phase separator and hydro cyclones. Algorithms were developed for system identification (NARX) using RLS(Recursive Least Square), along with methods for structure models detection. Predictive Control Algorithms were also implemented with NARX model updated on-line, and optimization algorithms using PSO (Particle Swarm Optimization). This project ends with a comparison of results obtained from the use of PI and predictive controllers (both with optimal state through the algorithm of cloud particles) in the simulated system. Thus, concluding that the performed optimizations make the system less sensitive to external perturbations and when optimized, the two controllers show similar results with the assessment of predictive control somewhat less sensitive to disturbances