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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Expressão da proteína prion celular no modelo da pilocarpina de epilepsia do lobo temporal

Rockenbach, Isabel Cristina January 2010 (has links)
Ratos que não expressam a proteína prion celular (PrPc) são mais sensíveis a crises epilépticas induzidas por diferentes protocolos. O hipocampo desses animais apresenta um brotamento supragranular de fibras musgosas semelhante ao observado em pacientes com epilepsia de lobo temporal relacionada a esclerose hipocampal (ELT-EH). Esses achados sugerem que a PrPc pode estar envolvida na epileptogênese da ELT-EH. Nós estudamos nessa tese a localização imunoistoquímica da PrPc no hipocampo de animais submetidos ao modelo de epilepsia de lobo temporal por pilocarpina (MELTP)em diferentes tempos de status epilepticus em ratos. Nesse trabalho induzimos estado de mal epileptico (EE) com o uso de pilocarpina em três diferentes grupos de ratos Wistar adultos. Os animais foram sacrificados 18 horas, 5 dias e 2 meses após a indução do EE. Os resultados foram comparados com cérebros controles de ratos que receberam injeções de solução salina. As lâminas foram processadas para coloração por hematoxilinaeosina, imunohistoquímica e neo-Timm. Observamos um aumento da expressão de PrPc nas regiões CA1 e CA3 do hipocampo 18 horas depois da injeção de pilocarpina. Essa expressão aumentada persistiu na região CA1 no quinto dia após a injeção. Não observamos diferenças significativas na expressão de PrPc durante a fase aguda do MELTP nas regiões CA2 e granular do hipocampo. No grupo crônico (2 meses) a PrPc foi observada na mesma localização em que se observou brotamento de fibras musgosas. Concluímos com esse trabalho que a expressão da PrPc é diferente nas diversas fases do modelo de epilepsia induzido por pilocarpina. A expressão transitória da proteína prion durante a fase aguda do modelo pode refletir mudanças de expressão visando tornar as células mais resistentes ao dano induzido pelas crises convulsivas. Alternativamente, essa expressão aumentada pode estar relacionadas à apotose ou então às fases iniciais da neuroplasticidade. A expressão de PrPc na mesma região dos brotamentos de fibras musgosas na fase crônica pode estar relacionada à neuroplasticidade, epileptogênese, neurotransmissão ou, ainda, estar implicada na proteção celular contra crises convulsivas recorrentes. Devido aos diversos achados relacionados a PrPc, sugerimos que o modelo de epilepsia do lobo temporal induzido pela pilocarpina possa ser um interessante modelo para o estudo do papel fisiológico da PrPc. / Mice lacking cellular prion protein (PrPc) are more sensitive to seizures induced by four different pharmacological protocols. The hippocampal formation of these animals exhibits supragranular mossy fiber sprouting which resembles that observed in patients with mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLEHS). These findings suggest that the PrPc may be involved in epileptogenesis in MTLE-HS. Here we investigated the immunohistochemical localization of the PrPc in the hippocampus of animals submitted to the pilocarpine model of temporal lobe epilepsy (PMTLE). Status epilepticus (SE) was induced with pilocarpine in three different groups of adult Wistar rats. The animals were sacrificed 18 hours, 5 days, and 2 months after SE induction and the results were compared to the respective saline-injected control animals. Slices were processed for hematoxylin-eosin, PrPc immunohistochemistry and neo-Timm .PrPc was increased in the CA1 and in CA3 regions of the hippocampus 18 hours after pilocarpine injection. PrPc continued to be increased in the CA1 region of the hippocampus five days after pilocarpine injection. In the CA2 and granular regions of the hippocampus we did not observe significant differences in PrPc expression during the acute phase of PMTLE. In the chronic group, PrPc was expressed co-localized with mossy fiber sprouting. Cellular prion protein is differentially expressed at different phases of the pilocarpine model of epilepsy. Transient expression of PrPc during the acute phase of the pilocarpine model may reflect changes which may render cells more resistant to seizure-induced damage and may be related to apoptosis or may to the initial phases of neuroplasticity. During the chronic period, PrPc is co-expressed in the same regions of mossy fiber sprouting. In chronic animals, PrPc might be related to neuroplasticity, epileptogenic processes, neurotransmission, or alternatively may be implicated in cellular protection against recurrent seizures.
152

Isolamento social precoce e consumo de uma dieta hiperlipídica : implicações no comportamento do tipo depressivo e em aspectos cognitivos em ratos adultos

Arcego, Danusa Mar January 2017 (has links)
Intervenções ambientais, como a exposição precoce a estressores ou a dietas ricas em calorias, podem alterar a trajetória da maturação neural e influenciar na susceptibilidade a certas patologias a longo-prazo. Neste contexto, o objetivo do presente estudo foi investigar os efeitos de uma exposição ao isolamento social durante o período pré-pubere associado ou não ao consumo precoce e crônico de uma dieta hiperlipídica (HFD) sobre aspectos cognitivos e emocionais, e possíveis mecanismos neuroquímicos associados a essas alterações, no hipocampo, no córtex pré-frontal e no núcleo accumbens de ratos machos na idade adulta. Os resultados mostraram que os dois fatores, estresse e dieta (separadamente), induziram um comportamento do tipo depressivo nos animais na idade adulta. Além disso, os animais isolados apresentaram um déficit cognitivo associado à memória de curta-duração e de trabalho, enquanto que animais com acesso à HFD demonstraram prejuízo somente na memória de curta-duração. Curiosamente, a interação entre os fatores (estresse e dieta) causou uma reversão dos déficits na memória de curta-duração. Em relação às avaliações do comportamento alimentar hedônico, observamos que o grupo com consumo crônico de HFD apresentou uma menor motivação para obter diferentes tipos de alimentos palatáveis doces. Essa redução motivacional não parece ser associada a uma menor palatabilidade e/ou a uma maior saciedade induzida pela HFD. Em relação aos marcadores de plasticidade analisados no córtex pré-frontal, observamos interações entre os fatores estresse e dieta na atividade da enzima Na+K+-ATPase, nos níveis de BNDF e no imunoconteúdo das proteínas AKT e MAPK/ERK, sendo que os fatores quando aplicados isolados diminuem os níveis dos parâmetros analisados, porém quando associados, os níveis retornam ou aumentam em relação aos valores do grupo controle. O hipocampo foi a estrutura mais afetada pelas intervenções ambientais neste trabalho. Observamos que tanto o estresse, como a dieta hiperlipídica (separadamente) causaram uma redução da plasticidade sináptica hipocampal, por meio de diferentes mecanismos: o acesso crônico à HFD afeta proteínas relacionadas ao funcionamento das sinapses, enquanto o isolamento social parece afetar mais particularmente a via de sinalização do BDNF. Com relação aos achados neuroquímicos no núcleo accumbens, observamos uma redução dos receptores dopaminérgico-1 (D1) e canabinóide-1 (CB1) com o consumo de HFD, enquanto que os animais isolados na pré-puberdade apresentaram uma redução do metabolismo dopaminérgico nesta estrutura. Em suma, esta tese demonstra que tanto o isolamento social e como o consumo contínuo de HFD causam comportamento do tipo depressivo e outras alterações comportamentais, e reduzem marcadores de plasticidade importantes no córtex prefrontal e hipocampo. O acesso à HFD também causa uma menor motivação para o comportamento alimentar hedônico. Assim, tais eventos precoces podem afetar a plasticidade neural levando a importantes alterações comportamentais, e assim predispor a diferentes patologias durante a vida. / Environmental interventions, such as early exposure to stressors or high calorie-diets, can alter the trajectory of neural maturation and influence the susceptibility to some pathologies throughout life. In this context, the aim of the present study was to investigate the effects of exposure to social isolation, during the pre-pubertal period, associated or not with early and chronic consumption of a hyperlipid diet (HFD) on cognitive and emotional aspects, and possible mechanisms associated with these changes, in the hippocampus, the prefrontal cortex and the nucleus accumbens of male rats in adulthood. The results showed that both pre-pubertal social isolation and chronic access to a hyperlipidic diet induced a depressive-like behavior in animals during adulthood. In addition, isolated animals had a cognitive deficit associated with short-term and working memory, whereas animals with access to HFD demonstrated impairment only in short-term memory. Interestingly, the interaction between the factors (stress and diet) caused a reversal in relation to short-term memory, remaining similar to the control group. Regarding the evaluations of the hedonic eating behavior, we observed that HFD group presented a lower motivation to obtain different sweet palatable foods. This impaired motivation does not appear to be associated with less palatability and/or satiety induced by the high-fat diet. Concerning plasticity markers in the prefrontal cortex, we observed interactions between stress and diet on Na+ K+-ATPase activity, BNDF levels and AKT and MAPK/ERK immunocontents. These interactions follow a similar profile: when applied alone, the levels of the analyzed parameters decrease, but when associated, the levels return or increase in relation to the values of the control group. The hippocampus was the structure most affected by the environmental interventions. Both stress and HFD caused a reduction of hippocampal synaptic plasticity through different mechanisms: chronic access to HFD affects proteins related to synaptic function, while social isolation affects the BDNF signaling pathway more significantly. Regarding the neurochemical findings in the nucleus accumbens, we observed a reduction in dopaminergic-1 (D1) and cannabinoid-1 (CB1) receptors with chronic HFD intake, whereas isolated animals had a reduction of dopaminergic metabolism in this same structure. In summary, this thesis shows that both social isolation and chronic consumption of HFD lead to depressive-like behavior and to other behavioral changes; they reduce plasticity markers in prefrontal cortex and hippocampus. HFD access also induced a lower motivation for hedonic feeding. Therefore, these early interventions may affect neural plasticity, leading to important behavioral changes, and thus, predispose to different pathologies later in life.
153

Investigating the Efficacy of Novel TrkB Agonists to Augment Stroke Recovery

January 2013 (has links)
abstract: Stroke remains the leading cause of adult disability in developed countries. Most survivors live with residual motor impairments that severely diminish independence and quality of life. After stroke, the only accepted treatment for these patients is motor rehabilitation. However, the amount and kind of rehabilitation required to induce clinically significant improvements in motor function is rarely given due to the constraints of our current health care system. Research reported in this dissertation contributes towards developing adjuvant therapies that may augment the impact of motor rehabilitation and improve functional outcome. These studies have demonstrated reorganization of maps within motor cortex as a function of experience in both healthy and brain-injured animals by using intracortical microstimulation technique. Furthermore, synaptic plasticity has been identified as a key neural mechanism in directing motor map plasticity, evidenced by restoration of movement representations within the spared cortical tissue accompanied by increase in synapse number translating into motor improvement after stroke. There is increasing evidence that brain-derived neurotrophic factor (BDNF) modulates synaptic and morphological plasticity in the developing and mature nervous system. Unfortunately, BDNF itself is a poor candidate because of its short half-life, low penetration through the blood brain barrier, and activating multiple receptor units, p75 and TrkB on the neuronal membrane. In order to circumvent this problem efficacy of two recently developed novel TrkB agonists, LM22A-4 and 7,8-dihydroxyflavone, that actively penetrate the blood brain barrier and enhance functional recovery. Findings from these dissertation studies indicate that administration of these pharmacological compounds, accompanied by motor rehabilitation provide a powerful therapeutic tool for stroke recovery. / Dissertation/Thesis / Ph.D. Neuroscience 2013
154

Expressão da proteína prion celular no modelo da pilocarpina de epilepsia do lobo temporal

Rockenbach, Isabel Cristina January 2010 (has links)
Ratos que não expressam a proteína prion celular (PrPc) são mais sensíveis a crises epilépticas induzidas por diferentes protocolos. O hipocampo desses animais apresenta um brotamento supragranular de fibras musgosas semelhante ao observado em pacientes com epilepsia de lobo temporal relacionada a esclerose hipocampal (ELT-EH). Esses achados sugerem que a PrPc pode estar envolvida na epileptogênese da ELT-EH. Nós estudamos nessa tese a localização imunoistoquímica da PrPc no hipocampo de animais submetidos ao modelo de epilepsia de lobo temporal por pilocarpina (MELTP)em diferentes tempos de status epilepticus em ratos. Nesse trabalho induzimos estado de mal epileptico (EE) com o uso de pilocarpina em três diferentes grupos de ratos Wistar adultos. Os animais foram sacrificados 18 horas, 5 dias e 2 meses após a indução do EE. Os resultados foram comparados com cérebros controles de ratos que receberam injeções de solução salina. As lâminas foram processadas para coloração por hematoxilinaeosina, imunohistoquímica e neo-Timm. Observamos um aumento da expressão de PrPc nas regiões CA1 e CA3 do hipocampo 18 horas depois da injeção de pilocarpina. Essa expressão aumentada persistiu na região CA1 no quinto dia após a injeção. Não observamos diferenças significativas na expressão de PrPc durante a fase aguda do MELTP nas regiões CA2 e granular do hipocampo. No grupo crônico (2 meses) a PrPc foi observada na mesma localização em que se observou brotamento de fibras musgosas. Concluímos com esse trabalho que a expressão da PrPc é diferente nas diversas fases do modelo de epilepsia induzido por pilocarpina. A expressão transitória da proteína prion durante a fase aguda do modelo pode refletir mudanças de expressão visando tornar as células mais resistentes ao dano induzido pelas crises convulsivas. Alternativamente, essa expressão aumentada pode estar relacionadas à apotose ou então às fases iniciais da neuroplasticidade. A expressão de PrPc na mesma região dos brotamentos de fibras musgosas na fase crônica pode estar relacionada à neuroplasticidade, epileptogênese, neurotransmissão ou, ainda, estar implicada na proteção celular contra crises convulsivas recorrentes. Devido aos diversos achados relacionados a PrPc, sugerimos que o modelo de epilepsia do lobo temporal induzido pela pilocarpina possa ser um interessante modelo para o estudo do papel fisiológico da PrPc. / Mice lacking cellular prion protein (PrPc) are more sensitive to seizures induced by four different pharmacological protocols. The hippocampal formation of these animals exhibits supragranular mossy fiber sprouting which resembles that observed in patients with mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLEHS). These findings suggest that the PrPc may be involved in epileptogenesis in MTLE-HS. Here we investigated the immunohistochemical localization of the PrPc in the hippocampus of animals submitted to the pilocarpine model of temporal lobe epilepsy (PMTLE). Status epilepticus (SE) was induced with pilocarpine in three different groups of adult Wistar rats. The animals were sacrificed 18 hours, 5 days, and 2 months after SE induction and the results were compared to the respective saline-injected control animals. Slices were processed for hematoxylin-eosin, PrPc immunohistochemistry and neo-Timm .PrPc was increased in the CA1 and in CA3 regions of the hippocampus 18 hours after pilocarpine injection. PrPc continued to be increased in the CA1 region of the hippocampus five days after pilocarpine injection. In the CA2 and granular regions of the hippocampus we did not observe significant differences in PrPc expression during the acute phase of PMTLE. In the chronic group, PrPc was expressed co-localized with mossy fiber sprouting. Cellular prion protein is differentially expressed at different phases of the pilocarpine model of epilepsy. Transient expression of PrPc during the acute phase of the pilocarpine model may reflect changes which may render cells more resistant to seizure-induced damage and may be related to apoptosis or may to the initial phases of neuroplasticity. During the chronic period, PrPc is co-expressed in the same regions of mossy fiber sprouting. In chronic animals, PrPc might be related to neuroplasticity, epileptogenic processes, neurotransmission, or alternatively may be implicated in cellular protection against recurrent seizures.
155

Impacto da inflamação aguda sobre a plasticidade sinaptica de motoneuronios espinhais apos avulsão das raizes nervosas / Impact of acute inflammation on spinal motoneuron synaptic plasticity following ventral root avulsion

Barbizan Petinari, Roberta, 1982- 15 August 2018 (has links)
Orientador: Alexandre Leite Rodrigues de Oliveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-15T21:42:08Z (GMT). No. of bitstreams: 1 BarbizanPetinari_Roberta_M.pdf: 3388045 bytes, checksum: 36c57768eef8605e519d96d0a068487a (MD5) Previous issue date: 2010 / Resumo: A avulsão das raízes nervosas ventrais (ARV) promove a axotomia dos motoneurônios na interface entre o sistema nervoso central e periférico. Sabe-se que apesar da intensa reação inflamatória, esta lesão, quando realizada durante o curso da encefalomielite autoimune experimental (EAE), resgata um significativo número de motoneurônios. A interpretação para tal evento seria a produção de fatores neurotróficos produzidos pelas células T. O presente trabalho teve por objetivo estudar a sobrevivência neuronal, bem como o processo de eliminação sináptica e a reatividade dos astrócitos e da microglia em relação aos motoneurônios axotomizados através de ARV, durante as fases de surto e remissão da EAE. Ratos Lewis fêmeas (n=30) com 7 semanas de idade foram submetidos à avulsão das raízes ventrais L4-L6. Esses animais foram divididos em 3 grupos: o GRUPO1 - não sofreu indução da doença. Dois grupos foram imunizados com proteína básica de mielina (MBP) associada à Mycobacterium tuberculosis (MT) para a indução da EAE, trinta minutos após a lesão nervosa, sendo o GRUPO2 - investigado na fase de surto e o GRUPO3 - na fase de remissão. As intumescências lombares foram dissecadas para a realização de imunoistoquímica e microscopia eletrônica de transmissão. Adicionalmente, a sobrevivência dos motoneurônios foi avaliada pela contagem dos motoneurônios presentes no núcleo motor dorsolateral da medula lombar na região da lesão corados com Nissl. Os resultados do presente estudo indicam que os animais axotomizados com EAE apresentaram menor reatividade da glia, tanto de astrócitos, quanto da microglia, maior cobertura sináptica e sobrevivência neuronal, em comparação aos animais somente avulsionados. Apesar da visão tradicional de que a resposta imune no SNC possa atuar negativamente na delicada rede neuronal, os presentes resultados apontam para um papel neuroprotetor do processo inflamatório durante o surto EAE. / Abstract: Ventral root avulsion is a proximal lesion of motoneurons in which the motor rootlets are torn out at the surface of the spinal cord resulting in extensive neuronal death. It has been previously shown that, if such lesion is performed during the course of the experimental autoimmune encephalomyelitis (EAE), a significant number of motoneurons can be rescued in spite of the intense inflammatory reaction. The interpretation for that is that the influx of T cells results in the production of a number of neurotrophic factors. Synaptological changes may be involved in neuronal degeneration and the better understanding of its role may be of importance for developing new strategies leading to neuronal survival. In this sense, the objective of the present work was to evaluate neuronal survival, astroglial reaction and synaptic inputs changes within the motor nucleus after ventral root avulsion during peak disease and after EAE remission. Lewis rats were subjected to unilateral avulsion of lumbar ventral roots (VRA) which were divided into tree groups: only VRA, VRA at peak of EAE and VRA during EAE remission. The animals were sacrificed and their lumbar spinal cords processed for immunohistochemistry, transmission electron microscopy (TEM) and motoneuron counting. The results indicated a reduction in glial reaction, increase in the synaptic covering of the motoneurons and neuronal survival in VRA+EAE compared to VRA alone. The present findings indicate that CNS inflammation may influence positivelly the synaptic plasticity as well as the stability of neuronal networks. This may in turn positively influence the survival of lesioned neurons. / Mestrado / Anatomia / Mestre em Biologia Celular e Estrutural
156

Efeitos da cúrcuma na recuperação funcional após hemissecção medular / Effects of curcumin on functional recovery after medular hemisection

Valéria Mendes da Rocha 22 September 2017 (has links)
A lesão medular é uma injúria do sistema nervoso central que resulta em grande déficit funcional. É uma condição relacionada ao desenvolvimento industrial e tecnológico e acomete principalmente adultos jovens em idade produtiva. Apesar de algumas tentativas terapêuticas estarem sob investigação, ainda não há tratamento eficaz que garanta recuperação funcional. A maioria das estratégias utilizadas visa estimular eventos de neuroplasticidade. A cúrcuma é um composto dietético que tem potencial terapêutico por interferir em processos inflamatórios, oxidativos e imunológicos. O presente estudo investigou possíveis efeitos terapêuticos da cúrcuma após hemissecção medular em ratos. O protocolo experimental foi aprovado pelo Comitê de Ética em Uso de Animais da Escola de Artes, Ciências e Humanidades. Os animais foram submetidos à hemissecção medular após a medula espinhal ser exposta por laminectomia. Os animais foram divididos em 2 grupos experimentais: i) lesionado com cúrcuma (LC); ii) lesionado sem tratamento (LS). Os testes comportamentais BBB Score, Combined Behavior Score, plano inclinado e Beam Walking foram realizados 24h, 72h e 7 dias depois da lesão para avaliar o reaprendizado medular e a recuperação funcional. Os resultados demonstraram melhora do comportamento sensitivo-motor dos animais, provavelmente envolvendo neuroproteção das vias de tato, dor e pressão. As propriedades anti-inflamatórias e antioxidantes da cúrcuma podem ter levado à melhora funcional. Análises celulares e moleculares são necessárias para entendermos melhor os efeitos no epicentro da lesão depois do tratamento com a cúrcuma. Um dos possíveis efeitos prováveis é sobre a conversão de alguns ácidos graxos envolvidos na inflamação, como o ácido araquidônico, diminuindo sua ação e gerando ganhos funcionais. O uso da cúrcuma na fase aguda da hemissecção medular interferiu positivamente na recuperação sensitivo-motora deflagrando, portanto, eventos de neuroproteção e neuroplasticidade / The spinal cord injury is a condition that results in severe functional deficit. It is related to the industrial and technological development and affects mainly young adults. Despite some therapeutic trials are under investigation, there is no treatment that guarantees functional recovery. Most of those strategies for recovery involve neuroplasticity. Curcumin is a dietetic compound with known therapeutic potential, interfering on inflammatory, oxidative and immunological processes. The present study investigated the effects of the treatment with curcumin on acute phase of spinal cord hemi-section in rats. The protocol has been approved by Ethics Committee of School of Arts, Sciences and Humanities. The animals were submitted to hemi-section after laminectomy and were divided in two groups: i) injured with curcumin (LC); ii) injured without treatment (LS). The following behavioral tests were performed 24h, 72h and 7 days after lesion: BBB Score, Combined Behavior Score, inclined plane and Beam Walking test aiming to evaluate medular relearning and functional recovery. The tests indicated an improvement of the sensitive-motor behavior probably by neuroprotection of tactile, pain and pressure pathways. The anti antiinflammatory and antioxidant properties of curcumin could result in functional improvement. Cellular and molecular analysis are necessary to better understand the effects could be over the conversion of some fatty acids involved on inflammation, such as arachidonic acid, reducing its action and promoting functional gain. The use of curcumin in the acute phase of spinal cord hemi-section seems to interfere positively in sensorial-motor recovery triggering neuroprotection and plasticity
157

L'expérience théâtrale comme expérience de transformation : théâtre et neuroscience des émotions / The theatrical experience as a transformative experience : theater and neuroscience of emotion

Calvert, Dorys Faria 25 November 2014 (has links)
Il s’agit d’une étude interdisciplinaire – englobant essentiellement le théâtre, la psychologie et les neurosciences – dont le but est celui d’analyser le potentiel transformateur (et, d’une certaine manière, thérapeutique) inhérent à la pratique théâtrale. Ce travail se divise en deux axes centraux d’investigation : le premier se concentre sur le dialogue que le théâtre a entretenu avec les sciences de la vie au long de l’histoire de la civilisation occidentale tout en mettant en avant l’idée selon laquelle l’étude scientifique des émotions se présente comme le fil conducteur des échanges théorico-pratiques entre les arts scéniques et les sciences du vivant. Le deuxième axe de ce travail de recherche concerne les rapports entre les neurosciences contemporaines des émotions, le travail de l’acteur et les modifications que le l’expérience théâtrale peut opérer – surtout chez l’acteur – sur le plan ontologique. Dans ce travail de recherche, quelques notions neuroscientifiques qui s’avèrent fondamentales pour l’élaboration d’une approche neurobiologique du travail émotionnel de l’acteur ont été développées. Ce sont : la neuroplasticité, le système de neurones miroirs, le circuit cérébral du plaisir et l’utilisation consciente de la mémoire procédurale. / This is an interdisciplinary study – essentially encompassing theater, psychology and neuroscience – whose goal is to analyze the transforming (and, somehow, therapeutic) potential inherent to theater practice. This work is divided into two core areas of investigation: the first focuses on the dialogue that the theater has had with the life sciences throughout the history of Western civilization, highlighting the idea that the scientific study of emotions is presented as the main thread between theoretical and practical exchanges of the performing arts and life sciences. The second focus area of this research concerns the relationship between contemporary neuroscience of emotions, the work of the actor and the transformations that could occur through the theatrical experience – especially for the actor – on an ontological level. In this research, some neuroscientific concepts that prove fundamental to the development of a neurobiological approach to the emotional work of the actor have been developed. They are: neuroplasticity, the neuron mirror system, the brain gratification circuit and the conscious use of the procedural memory.
158

Imaging Pain And Brain Plasticity: A Longitudinal Structural Imaging Study

Bishop, James Hart 01 January 2017 (has links)
Chronic musculoskeletal pain is a leading cause of disability worldwide yet the mechanisms of chronification and neural responses to effective treatment remain elusive. Non-invasive imaging techniques are useful for investigating brain alterations associated with health and disease. Thus the overall goal of this dissertation was to investigate the white (WM) and grey matter (GM) structural differences in patients with musculoskeletal pain before and after psychotherapeutic intervention: cognitive behavioral therapy (CBT). To aid in the interpretation of clinical findings, we used a novel porcine model of low back pain-like pathophysiology and developed a post-mortem, in situ, neuroimaging approach to facilitate translational investigation. The first objective of this dissertation (Chapter 2) was to identify structural brain alterations in chronic pain patients compared to healthy controls. To achieve this, we examined GM volume and diffusivity as well as WM metrics of complexity, density, and connectivity. Consistent with the literature, we observed robust differences in GM volume across a number of brain regions in chronic pain patients, however, findings of increased GM volume in several regions are in contrast to previous reports. We also identified WM changes, with pain patients exhibiting reduced WM density in tracts that project to descending pain modulatory regions as well as increased connectivity to default mode network structures, and bidirectional alterations in complexity. These findings may reflect network level dysfunction in patients with chronic pain. The second aim (Chapter 3) was to investigate reversibility or neuroplasticity of structural alterations in the chronic pain brain following CBT compared to an active control group. Longitudinal evaluation was carried out at baseline, following 11-week intervention, and a four-month follow-up. Similarly, we conducted structural brain assessments including GM morphometry and WM complexity and connectivity. We did not observe GM volumetric or WM connectivity changes, but we did discover differences in WM complexity after therapy and at follow-up visits. To facilitate mechanistic investigation of pain related brain changes, we used a novel porcine model of low back pain-like pathophysiology (Chapter 6). This model replicates hallmarks of chronic pain, such as soft tissue injury and movement alteration. We also developed a novel protocol to perform translational post-mortem, in situ, neuroimaging in our porcine model to reproduce WM and GM findings observed in humans, followed by a unique perfusion and immersion fixation protocol to enable histological assessment (Chapter 4). In conclusion, our clinical data suggest robust structural brain alterations in patients with chronic pain as compared to healthy individuals and in response to therapeutic intervention. However, the mechanism of these brain changes remains unknown. Therefore, we propose to use a porcine model of musculoskeletal pain with a novel neuroimaging protocol to promote mechanistic investigation and expand our interpretation of clinical findings.
159

Tanec očima nevidomých / Dancing with the Eyes of the Blind

Stráníková, Anežka January 2017 (has links)
This diploma thesis is focused on issues of dance in relation to blind people. The goal of the thesis is to find out how to compensate for a blind person's lack of visual perception through dance. A secondary goal is to explore what dance means to blind people. The research is based on theoretical solutions obtained by analysis of available sources and based on research using qualitative strategies. To fulfill the research task, techniques of participant observation and interviews were used. From the data obtained through semi-structured interviews and observation of blind respondents in the framework of dance events, it has been found that dance is an effective form of stimulation and development of the compensatory senses of blind people. Most significantly dance influenced the participants' perception of their bodies, developing their capabilities and ability to respond to internal and external stimuli. The results of other interviews show that all blind participants have experience with dance. This experience is overwhelmingly positive. The survey confirms the importance of dance for blind people in the planes of their physical, mental and social faculties. KEY WORDS blindness, dance, compensation, perception, senses, movements, neuroplasticity
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Impact des modalités d'un exercice physique sur la neuroplasticité. Focus sur les sources de BDNF / Impact of exercise modalities on neuroplasticity. Focus on BDNF sources

Cefis, Marina 08 November 2019 (has links)
L’exercice physique (EX) est reconnu comme la stratégie non pharmacologique la plus efficace pour améliorer la santé cérébrale. Les études menées chez l’Homme et l’animal s’accordent pour impliquer le brain-derived neurotrophic factor (BDNF), une neurotrophine dont les taux cérébraux augmentent en réponse à l’EX et qui est unanimement reconnue comme une molécule de signalisation cruciale de la neuroplasticité. Principalement exprimé par les neurones, le BDNF est également très exprimé par la cellule endothéliale et la cellule musculaire. Très largement sollicités lors d’un effort physique, l’endothélium et le muscle pourraient intervenir dans les effets positifs induits par l’EX. Bien qu’il existe aujourd’hui un consensus sur l’implication du BDNF dans les effets cérébraux de l’EX, il n’en existe pas concernant les modalités d’EX à pratiquer pour optimiser de manière efficace la plasticité cérébrale. Dans ce contexte, les objectifs de ces travaux étaient de déterminer l’impact des modalités de l’EX sur les expressions protéiques de BDNF dans différents territoires (cerveau, endothélium, muscle) et d’étudier les mécanismes à l’origine de l’augmentation de BDNF en réponse à l’EX.Nos résultats montrent que 1) l’expression du BDNF dans des vaisseaux périphériques de même territoire vasculaire (diamètre interne différent) est similaire en réponse à l’EX et majoritairement d’origine endothéliale, 2) l’augmentation de l’expression cérébrale de BDNF en réponse à l’EX dépend de l’intensité de l’EX, mais pas du type de contraction (excentrique/concentrique), 3) la mémoire est restaurée par un EX de forte intensité, 4) l’EX n’impacte pas l’expression musculaire de BDNF, mais augmente l’expression du précurseur de l’irisine (FNDC5), 5) l’expression du BDNF dépend de la composition du muscle en fibres musculaires, 6) les effets cérébraux de l’intensité de l’EX ne semblent pas être reliés à la surexpression de l’irisine musculaire.En conclusion, nos données démontrent que l’EX impacte positivement l’expression endothéliale, cérébrale mais pas musculaire de BDNF. Les résultats mettent en évidence l’importance du paramètre intensité de l’EX sur les taux cérébraux de BDNF. Enfin, selon nos données obtenues, l’irisine et le BDNF musculaires ne semblent pas être impliqués dans l’augmentation cérébrale de BDNF en fonction de l’intensité de l’EX. / Physical exercise (EX) is recognized as the most potent non-pharmacological strategy to positively enhance brain health. From Human and animal studies there is a consensus to involve brain-derived neurotrophic factor (BDNF), a neurotrophin strongly expressed in response to EX and implicated in neuroplasticity mechanisms. Mainly expressed by neurons, BDNF is also expressed by endothelial and muscle cells. Largely sought during a physical effort, endothelium and skeletal muscle could be involved in positive effects induced by EX. Although there is a real consensus about BDNF and cerebral effect of EX, the typology of the better regimen of EX to enhance cerebral plasticity is not known. In this context, objectives of this works were to determine the impact of EX modalities on BDNF protein expression in different territory (brain, endothelium and muscle) and to identify mechanisms related in BDNF increases in response to EX.Our results showed that 1) BDNF expression in peripheral vessels from the same vascular territory (distinct internal diameter) is similar in response to EX, 2) cerebral BDNF increases induced by EX is dependent on EX intensity but not on the type of contraction (eccentric/concentric), 3) memory is restored by high intensity EX, 4) after EX, BDNF muscular expression is unchanged while the precursor of irisine (FNDC5) expression is increased, 5) BDNF expression depends on muscular fibers typology, 6) cerebral beneficial effects of EX intensity is might not be related to muscular irisine production.In conclusion, our data demonstrated that EX positively impact endothelial, cerebral but not muscular BDNF expression. Results highlighted the importance of the intensity parameter of EX on cerebral BDNF levels. Finally, according to our data, irisine and BDNF from the muscle might not be related to the cerebral increases of BDNF induced by EX intensity.

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