816 research outputs found
Desenvolvimento e implementação automatizados de recomendações clínicas
No full textDissertação de mestrado em Engenharia InformáticaCurrently the health sector where the growing needs to standardize medical practices and promote the improvement of clinical practice to reduce costs becomes increasingly important to find a solution that will allow these goals to be more easily achieved. For this the solution that best catches the interest currently is the use of Clinical Recommendations.
Clinics offer recommendations in the form of long documents advice of good medical practice, in which concepts are often vague and inconclusive and are rarely available at the time of the medical act. Hence arises the idea of representing these recommendations computationally, ie, use Computer-interpretable Guidelines (CIGS), which are structured representations of clinical recommendations that can be interpreted and implemented computationally.
The aim well this dissertation is the development of a web application that allows the creation and implementation of a simple and structured clinical guidelines allowing medical professionals to easily visualize and implement clinical recommendations.Atualmente no setor da saúde onde, a crescente necessidade de estandardizar as práticas
médicas e promover a melhoria das práticas clínicas de forma a reduzir os custos exige uma
solução que permita que estes objetivos sejam mais facilmente atingidos. Para o efeito, a
solução que mais desperta o interesse atualmente é a utilização de Recomendações de Práticas
Clínicas.
Recomendações Clínicas oferecem, na forma de documentos longos, conselhos de boas práticas
médicas em circunstâncias específicas. Contudo, por vezes os conceitos existentes nestes
documentos são vagos e inconclusivos. Para além disso, o seu tamanho e formato
desestruturado torna os difíceis de consultar e de estarem disponíveis no momento do ato
médico. Daqui surge a ideia de representar estas recomendações computacionalmente, isto é,
recorrer a Computer-Interpretable Guidelines, que são representações estruturadas de
recomendações clínicas, que podem ser interpretadas e executadas por máquinas.
O que se pretende assim nesta dissertação, é o desenvolvimento de uma aplicação web que
permita a criação e implementação de forma simples e estruturada de Recomendações Clínicas,
permitindo aos profissionais de saúde facilmente criá-las, aplicá-las e modificá-las.
A aplicação é capaz de, a partir do modelo de representação de guidelines, permitir a um
utilizador aplicar uma guideline representada e executá-la. A aplicação oferece todos os recursos
necessários para consultar recomendações clínicas, e armazena toda a informação processada e
gerada pela aplicação numa base de dados que está localizada junto com o servidor principal.
Conta ainda com uma aplicação web que permite a interface com o utilizador tanto para
executar guidelines como para gerir utilizadores
A Journey Around Tiago Rodrigues’ Room
No full textTiago Rodrigues is, today, one of the most credited European theatre artists.
From an actor who wrote and often directed his own texts, Rodrigues quickly began to establish
himself also as an author and director. There is an undoubtable singularity in Tiago
Rodrigues’ theatre. He is one of the clearest examples in contemporary world performance
of a Goethian drive for “world literature”. It is our argument that one of Rodrigues most
perceivable dramaturgical axes is a desire to pay homage to European humanistic traditions
as a gesture of political resistance through art and memory. His literary journey through the
words and titles of the past aim poignantly to supersede the failures of the present.info:eu-repo/semantics/acceptedVersio
TIAGO BAPTISTA: HISTÓRIAS DE HOMENS E LENDAS DA PINTURA
Get PDFResumoO presente artigo pretende dar a conhecer uma perspectiva individual do trabalho plástico do artista Tiago Baptista. Nele encontramos uma profunda relação com um universo de preocupações que se centralizam na identificação das nossas falhas humanas. Neste vasto contexto são convocadas antigas lendas da História da Pintura e são pressentidas variadas referências de autores que integram essa mesma história. Partindo da praxis do próprio autor, das suas palavras, e das palavras que outros construíram a partir das suas representações ambíguas, importa perceber como a simbiose das questões enumeradas sustentam as imagens criadas por Baptista.AbstractThis article aims to present an individual perspective on Tiago Baptista’s work. In it, we find a deep relationship with a universe of concerns related with the identification of our human flaws. In this wider context old legends about the History of Painting are called upon his work, mixed with several references of notable artists who integrate that same history. Through the praxis of this author, through his own words, and the words that others have found faire to create about this ambiguous representations, it is important to understand this specific symbiosis which supports the images made by Baptista
Littérature de parti et écriture normative: l’oeuvre de Manuel Tiago/Álvaro Cunhal
No full textEvery communist thesis’ novel, as well as every ideological conflict, divides human kind in good and bad ones, what originates a binary axiology: this can be found in the work of Manuel Tiago whose writing is explanatory and normative. The author often turns to a deontic modality, what characterizes the normative, as well as the evaluative commentaries and, consequently the epistemic modality. His first novel, Até Amanhã, Camaradas, written during the Salazar dictatorship, served as a manual for the PCP members, who should transform themselves in “professional revolutionaries”, fighting undercovered.---Original in French.Tout roman à thèse communiste, comme tout conflit idéologique, répartit l’humanité en bons et en méchants, ce qui donne lieu à une axiologie binaire : c’est ce que l’on observe dans l’œuvre de Manuel Tiago dont l’écriture est explicative et normative. L’auteur, d’ailleurs, recourt fréquemment à la modalité déontique, qui caractérise le normatif, ainsi qu’aux commentaires évaluatifs, et donc à la modalité épistémique. Son premier roman, Até Amanhã, Camaradas, écrit sous la dictature salazariste, a servi de manuel aux membres du PCP qui devaient se transformer en « révolutionnaires professionnels » en luttant dans la clandestinité.----------------------------------------------------------------------LITERATURA DE PARTIDO E ESCRITA NORMATIVA: A OBRA DE MANUEL TIAGO/ÁLVARO CUNHALTodo o romance de tese comunista, assim como todo o conflito ideológico, divide a humanidade em bons e maus, o que dá origem a uma axiologia binária : é o que se verifica na obra de Manuel Tiago cuja escrita é explicativa e normativa. O autor, aliás, recorre frequentemente à modalidade deôntica, que caracteriza o normativo, bem como aos comentários avaliadores e, consequentemente, à modalidade espitémica. O seu primeiro romance, Até Amanhã, Camaradas, escrito sob a ditadura salazarista, serviu de manual para os membros do PCP que deviam transformar-se em « revolucionários profissionais », lutando na clandestinidade.---Artigo em francês
A Compact Disc Recording of Three Commissioned Works Featuring the Clarinet by Portuguese Composers, which include Portuguese Folk Music Elements
Get PDFabstract: Despite the wealth of folk music traditions in Portugal and the importance of the clarinet in the music of bandas filarmonicas, it is uncommon to find works featuring the clarinet using Portuguese folk music elements. In the interest of expanding this type of repertoire, three new works were commissioned from three different composers. The resulting works are Seres Imaginarios 3 by Luis Cardoso; Delirio Barroco by Tiago Derrica; and Memória by Pedro Faria Gomes. In an effort to submit these new works for inclusion into mainstream performance literature, the author has recorded these works on compact disc. This document includes interview transcripts with each composer, providing first-person discussion of each composition, as well as detailed biographical information on each composer. To provide context, the author has included a brief discussion on Portuguese folk music, and in particular, the role that the clarinet plays in Portuguese folk music culture.Dissertation/ThesisSeres Imaginarios 3 - Movement I - Olhapim (composed by Luis Cardoso)Seres Imaginarios 3 - Movement II - Jana (composed by Luis Cardoso)Seres Imaginarios 3 - Movement III - Trasgo (composed by Luis Cardoso)Delirio Barroco - Movement I - Ouverture (composed by Tiago Derrica)Delirio Barroco - Movement II - Fantasia (composed by Tiago Derrica)Delirio Barroco - Movement III - Fuga (composed by Tiago Derrica)Delirio Barroco - Movement IV - Fantasia 2 (composed by Tiago Derrica)Delirio Barroco - Movement V - Coral (composed by Tiago Derrica)Memoria (composed by Pedro Faria Gomes)D.M.A. Music 201
From AMPAR lateral diffusion to whisker perception : a new model for cortical remapping
No full textLes champs récepteurs corticaux se réorganisent en réponse aux changements de l'environnement. Par exemple, suite à une lésion périphérique, les modalités sensorielles préservées gagnent de l'espace cortical au détriment de celles lésées. L'étude du cortex somatosensoriel en tonneau des rongeurs a fourni des données importantes pour la compréhension des mécanismes synaptiques à l'origine de cette réorganisation corticale. En condition normale, les neurones de chaque colonne corticale répondent préférentiellement à la stimulation d'une seule vibrisse principale ("Principal Whisker, PW"). Au contraire, suite à l'amputation de l'ensemble des vibrisses sauf une ("Single Whisker Experience, SWE"), les neurones des colonnes associées aux vibrisses amputées répondent à la stimulation de la vibrisse conservée, à l'origine du renforcement et de l'expansion des représentations corticales des vibrisses conservées. Bien que des preuves indirectes aient révélées un rôle de la potentialisation à long terme ("Long-Term Potentiation, LTP") de synapses préexistantes dans la modification des cartes corticales, probablement via une augmentation du nombre des récepteurs AMPA (AMPARs) aux synapses, un lien direct entre la LTP, la réorganisation des cartes corticales, et l'adaptation des comportements sensori-moteurs suite à une altération des entrées sensorielles n'a pas encore été démontré. L'objectif de cette thèse a donc été de mettre en évidence cette relation de façon expérimentale et en condition physiologique. Pour cela, nous avons mis au point une stratégie in vivo combinant des enregistrements électrophysiologiques, de l'imagerie biphotonique et l'analyse du comportement d'exploration chez la souris contrôle ("Full Whisker Experience, FWE) et amputée de certaines vibrisses (SWE). Nous avons d'abord confirmé que la stimulation rythmique de la PW ("Rhytmic Whisker Swtimulation, RWS") renforce les synapses excitatrices (RWS-LTP) in vivo des souris anesthésiées FWE. Au contraire des souris FWE, les neurones pyramidaux des souris SWE présentent une augmentation de l'excitabilité neuronale et une absence de RWS-LTP, indiquant ainsi que les synapses corticales associées à la vibrisse intacte ont été potentialisées en réponse au protocole SWE. Pour mieux comprendre l'implication de la RWS-LTP dans la réorganisation des cartes corticales et l'adaptation des comportements sensori-moteurs, nous avons développé une nouvelle approche pour manipuler la LTP in vivo grâce à l'immobilisation des AMPARs par des anticorps extracellulaires ("cross-linking"). En effet, notre équipe a montré précédemment que le cross-linking des AMPARs empêche la LTP in vitro. Par ailleurs, une accumulation des AMPARs au niveau post-synaptique a été démontrée in vivo par imagerie biphotonique au cours d'une stimulation RWS, suggérant un rôle de la mobilité de ces récepteurs dans cette RWS-LTP. Au cours de cette thèse, nous avons démontré que le cross-linking des AMPARs in vivo bloque également l'expression de la RWS-LTP, mais sans affecter la transmission synaptique basale, ni l'induction de la RWS-LTP, indiquant ainsi que la mobilité des AMPARs est également fondamental pour l'expression de la LTP in vivo. De façon importante, le cross-linking des AMPARs de façon chronique, au cours du SWE, permet non seulement de rétablir la RWS-LTP et l'excitabilité neuronale, et donc de bloquer la réorganisation corticale, mais aussi de modifier les capacités de récupération sensori-motrices des souris amputées. Dans l'ensemble, nos données démontrent pour la première fois un rôle critique et direct de la RWS-LTP dans le réarrangement des circuits en réponse à l'amputation de certaines vibrisses. La réorganisation des cartes corticales serait ainsi assurée par le renforcement de la transmission synaptique, et constituerait alors un mécanisme compensatoire pour optimiser le comportement sensorimoteur de l'animal lors de l'altération des entrées sensorielles.Neuronal receptive fields in the cerebral cortex change in response to peripheral injury, with active modalities gaining cortical space at the expense of less active ones. Experiments on the mouse whisker-to-barrel cortex system provided important evidences about the synaptic mechanisms driving this cortical remapping. Under normal conditions, neurons in each barrel-column have receptive fields that are strongly tuned towards one principal whisker (PW). However, trimming all the whiskers except one (single-whisker experience, SWE) causes layer (L) 2/3 pyramidal neurons located in the deprived and spared-related columns to increase their response towards the spared input. This results in a strengthening and expansion of the spared whisker representation within the barrel sensory map. Indirect evidences suggest that these cortical alterations might depend on the activity-dependent potentiation of pre-existing excitatory synapses (LTP), likely through increased levels of postsynaptic AMPA receptors (AMPARs). However, a clear link between LTP, cortical remapping, and the adaptation of sensorimotor skills following altered sensory experience has not yet convincingly been demonstrated. Here, we combined in vivo whole-cell recordings, 2-Photon calcium imaging and a whisker-dependent behavior protocol to directly demonstrate this relationship. It has been described that rhythmic whisker stimulation potentiates cortical synapses (RWS-LTP) in vivo. An accumulation of postsynaptic AMPARs during similar sensory stimulation was also reported by imaging evidences. Our data demonstrates that this potentiation is occluded by SWE, suggesting that cortical synapses are already potentiated by this trimming protocol. This is translated into an increased neuronal excitability in the spared column and sensorimotor recovery by the spared whisker. To better understand the implication of LTP in cortical remapping, we developed a novel approach to manipulate LTP in vivo without affecting overall circuit properties. Our team showed previously that the blockage of AMPARs synaptic recruitment by extracellular antibody cross-linking prevents LTP in vitro. Here, we report that in vivo cross-linking of AMPARs blocks the expression but not the induction of RWS-LTP, suggesting that the synaptic recruitment of AMPARs is fundamental for in vivo LTP as well. Moreover, chronic AMPAR cross-linking during SWE reverts RWS-LTP occlusion and the increased neuronal excitability caused by whisker trimming. As consequence, the sensorimotor performance by the spared whisker is permanently impaired by the blockage of cortical remapping. Altogether, these evidences led us to define a critical role for synaptic LTP on circuit re-arrangement after whisker trimming. Our data shows that LTP-driven cortical remapping is a compensatory mechanism to optimize animal’s sensorimotor behavior upon altered sensory experience
Para uma análise retórico-pragmática da Carta de Tiago do saber "destruidor" ao fazer "sabedor"
Get PDFA Carta de Tiago, eclipsada pelas epístolas de Paulo, é o objeto de investigação desse trabalho, a partir da teoria de uma abordagem retórico-pragmática, sobre a questão do dizer e do fazer. A análise tomará como referencial as teorias dos atos de fala de Austin e Searle, pois para ambos, as palavras não são meramente palavras, mas são ações que moldam o mundo e a realidade das pessoas. As palavras da Carta de Tiago são carregadas desse elemento significativo do fazer. Para o autor da Carta, discurso e prática caminham juntos. O discurso não pode estar dissociado da ação. Isso, quando se trata de fé e obra, mas sobretudo, quando se trata de ética. São questões que exigem uma pronta resposta. Suas exigências vão além de respostas prontas e retóricas, requer saídas, alternativas para suas crises que são as mais diversas. Crises que vão dos problemas econômicos, políticos, sociais, familiares, religiosos, tanto numa visão global, quanto numa visão localizada, portanto, a Carta de Tiago apresenta um discurso ético persuasivo que, a luz das teorias dos atos de fala, é posto em evidência, pois o discurso deve sair do dizer para o fazer.The Letter of James, eclipsed by the epistles of Paul, is the object of investigation of this work, from the theory of a rhetorical-pragmatic approach, on the question of saying and doing. The analysis will take as reference the theories of the acts of speech of Austin and Searle, because for both, the words are not merely words, but they are actions that shape the world and the reality of the people. The words of the Letter of James are loaded with this significant element of doing. For the author of the letter speech and practice walk together. Discourse can not be dissociated from action. This is when it comes to faith and works, but especially when it comes to ethics. These are questions that require a prompt response. Their demands go beyond ready and rhetorical answers, they require exits, alternatives to their crises that are the most diverse. Crises ranging from economic, political, social, family, religious problems, both in a global vision and in a localized vision, therefore the Charter presents a persuasive ethical discourse that the light of the theories of speech acts is put in evidence, since discourse must leave the saying to do so
De la diffusion latérale des récepteurs AMPA à la perception des whiskers : un nouveau modèle de cartographie corticale
No full textNeuronal receptive fields in the cerebral cortex change in response to peripheral injury, with active modalities gaining cortical space at the expense of less active ones. Experiments on the mouse whisker-to-barrel cortex system provided important evidences about the synaptic mechanisms driving this cortical remapping. Under normal conditions, neurons in each barrel-column have receptive fields that are strongly tuned towards one principal whisker (PW). However, trimming all the whiskers except one (single-whisker experience, SWE) causes layer (L) 2/3 pyramidal neurons located in the deprived and spared-related columns to increase their response towards the spared input. This results in a strengthening and expansion of the spared whisker representation within the barrel sensory map. Indirect evidences suggest that these cortical alterations might depend on the activity-dependent potentiation of pre-existing excitatory synapses (LTP), likely through increased levels of postsynaptic AMPA receptors (AMPARs). However, a clear link between LTP, cortical remapping, and the adaptation of sensorimotor skills following altered sensory experience has not yet convincingly been demonstrated. Here, we combined in vivo whole-cell recordings, 2-Photon calcium imaging and a whisker-dependent behavior protocol to directly demonstrate this relationship. It has been described that rhythmic whisker stimulation potentiates cortical synapses (RWS-LTP) in vivo. An accumulation of postsynaptic AMPARs during similar sensory stimulation was also reported by imaging evidences. Our data demonstrates that this potentiation is occluded by SWE, suggesting that cortical synapses are already potentiated by this trimming protocol. This is translated into an increased neuronal excitability in the spared column and sensorimotor recovery by the spared whisker. To better understand the implication of LTP in cortical remapping, we developed a novel approach to manipulate LTP in vivo without affecting overall circuit properties. Our team showed previously that the blockage of AMPARs synaptic recruitment by extracellular antibody cross-linking prevents LTP in vitro. Here, we report that in vivo cross-linking of AMPARs blocks the expression but not the induction of RWS-LTP, suggesting that the synaptic recruitment of AMPARs is fundamental for in vivo LTP as well. Moreover, chronic AMPAR cross-linking during SWE reverts RWS-LTP occlusion and the increased neuronal excitability caused by whisker trimming. As consequence, the sensorimotor performance by the spared whisker is permanently impaired by the blockage of cortical remapping. Altogether, these evidences led us to define a critical role for synaptic LTP on circuit re-arrangement after whisker trimming. Our data shows that LTP-driven cortical remapping is a compensatory mechanism to optimize animal’s sensorimotor behavior upon altered sensory experience.Les champs récepteurs corticaux se réorganisent en réponse aux changements de l'environnement. Par exemple, suite à une lésion périphérique, les modalités sensorielles préservées gagnent de l'espace cortical au détriment de celles lésées. L'étude du cortex somatosensoriel en tonneau des rongeurs a fourni des données importantes pour la compréhension des mécanismes synaptiques à l'origine de cette réorganisation corticale. En condition normale, les neurones de chaque colonne corticale répondent préférentiellement à la stimulation d'une seule vibrisse principale ("Principal Whisker, PW"). Au contraire, suite à l'amputation de l'ensemble des vibrisses sauf une ("Single Whisker Experience, SWE"), les neurones des colonnes associées aux vibrisses amputées répondent à la stimulation de la vibrisse conservée, à l'origine du renforcement et de l'expansion des représentations corticales des vibrisses conservées. Bien que des preuves indirectes aient révélées un rôle de la potentialisation à long terme ("Long-Term Potentiation, LTP") de synapses préexistantes dans la modification des cartes corticales, probablement via une augmentation du nombre des récepteurs AMPA (AMPARs) aux synapses, un lien direct entre la LTP, la réorganisation des cartes corticales, et l'adaptation des comportements sensori-moteurs suite à une altération des entrées sensorielles n'a pas encore été démontré. L'objectif de cette thèse a donc été de mettre en évidence cette relation de façon expérimentale et en condition physiologique. Pour cela, nous avons mis au point une stratégie in vivo combinant des enregistrements électrophysiologiques, de l'imagerie biphotonique et l'analyse du comportement d'exploration chez la souris contrôle ("Full Whisker Experience, FWE) et amputée de certaines vibrisses (SWE). Nous avons d'abord confirmé que la stimulation rythmique de la PW ("Rhytmic Whisker Swtimulation, RWS") renforce les synapses excitatrices (RWS-LTP) in vivo des souris anesthésiées FWE. Au contraire des souris FWE, les neurones pyramidaux des souris SWE présentent une augmentation de l'excitabilité neuronale et une absence de RWS-LTP, indiquant ainsi que les synapses corticales associées à la vibrisse intacte ont été potentialisées en réponse au protocole SWE. Pour mieux comprendre l'implication de la RWS-LTP dans la réorganisation des cartes corticales et l'adaptation des comportements sensori-moteurs, nous avons développé une nouvelle approche pour manipuler la LTP in vivo grâce à l'immobilisation des AMPARs par des anticorps extracellulaires ("cross-linking"). En effet, notre équipe a montré précédemment que le cross-linking des AMPARs empêche la LTP in vitro. Par ailleurs, une accumulation des AMPARs au niveau post-synaptique a été démontrée in vivo par imagerie biphotonique au cours d'une stimulation RWS, suggérant un rôle de la mobilité de ces récepteurs dans cette RWS-LTP. Au cours de cette thèse, nous avons démontré que le cross-linking des AMPARs in vivo bloque également l'expression de la RWS-LTP, mais sans affecter la transmission synaptique basale, ni l'induction de la RWS-LTP, indiquant ainsi que la mobilité des AMPARs est également fondamental pour l'expression de la LTP in vivo. De façon importante, le cross-linking des AMPARs de façon chronique, au cours du SWE, permet non seulement de rétablir la RWS-LTP et l'excitabilité neuronale, et donc de bloquer la réorganisation corticale, mais aussi de modifier les capacités de récupération sensori-motrices des souris amputées. Dans l'ensemble, nos données démontrent pour la première fois un rôle critique et direct de la RWS-LTP dans le réarrangement des circuits en réponse à l'amputation de certaines vibrisses. La réorganisation des cartes corticales serait ainsi assurée par le renforcement de la transmission synaptique, et constituerait alors un mécanisme compensatoire pour optimiser le comportement sensorimoteur de l'animal lors de l'altération des entrées sensorielles
O riso melancólico do absurdo [Encontrar o Sol e Karl Valentin Kabarett, Teatro do Eléctrico]
No full textCrítica aos espectáculos Encontrar o Sol. Autor: Edward Albee. Encenação: Ricardo Neves‑Neves. Tradução: João Paulo Esteves da Silva. Direcção musical: João Paulo Esteves da Silva. Apoio vocal: João Henriques. Sonoplastia: Sérgio Delgado. Luz: Elduplo. Cenografia: Tiago Pinhal Costa. Figurinos: José António Tenente. Interpretação: Cucha Carvalheiro, Custódia Gallego, Luís Gaspar, Marques d’Arede, Romeu Costa, Rita Cruz, Tânia Alves e Tadeu Faustino. Produção: Teatro do Eléctrico, Theatro Circo e São Luiz Teatro Municipal. Local e data de estreia: Sala Luis Miguel Cintra do São Luiz Teatro Municipal, Lisboa, 17 de Fevereiro de 2017; Karl Valentin Kabarett. Autor: Karl Valentin. Encenação: Ricardo Neves‑ ‑Neves. Tradução: Almeida Faria, Jorge Silva Melo, Luíza Neto Jorge, Maria Adélia Silva Melo e Osório Mateus. Assistência de encenação: Rafael Gomes. Direcção musical: Rita Nunes. Apoio vocal: João Henriques. Orquestra: Francisco Andrade, Ivo Rodrigues, José Almeida, José Massarrão, Marcos Lazáro, Rita Nunes, Rui Pereira, Simon Wadsworth, Tomás Pimentel e Xavier Ribeiro. Cantor: Tiago Amado Gomes. Sonoplastia: Sérgio Delgado. Coreografia: Tiago Careto. Figurinos: Rafaela Mapril. Interpretação: Elsa Galvão, Fernando Gomes, Joana Campelo, José Leite, Márcia Cardoso, Rafael Gomes, Rita Cruz, Sílvia Figueiredo, Tadeu Faustino, Tânia Alves e Vítor Oliveira. Produção: Teatro do Eléctrico, Festival de Almada e Teatro da Trindade. Local e data de estreia: Palco Grande da Escola D. António da Costa, Festival de Almada, Almada, 10 de Julho de 2017
De la diffusion latérale des récepteurs AMPA à la perception des whiskers : un nouveau modèle de cartographie corticale
No full textNeuronal receptive fields in the cerebral cortex change in response to peripheral injury, with active modalities gaining cortical space at the expense of less active ones. Experiments on the mouse whisker-to-barrel cortex system provided important evidences about the synaptic mechanisms driving this cortical remapping. Under normal conditions, neurons in each barrel-column have receptive fields that are strongly tuned towards one principal whisker (PW). However, trimming all the whiskers except one (single-whisker experience, SWE) causes layer (L) 2/3 pyramidal neurons located in the deprived and spared-related columns to increase their response towards the spared input. This results in a strengthening and expansion of the spared whisker representation within the barrel sensory map. Indirect evidences suggest that these cortical alterations might depend on the activity-dependent potentiation of pre-existing excitatory synapses (LTP), likely through increased levels of postsynaptic AMPA receptors (AMPARs). However, a clear link between LTP, cortical remapping, and the adaptation of sensorimotor skills following altered sensory experience has not yet convincingly been demonstrated. Here, we combined in vivo whole-cell recordings, 2-Photon calcium imaging and a whisker-dependent behavior protocol to directly demonstrate this relationship. It has been described that rhythmic whisker stimulation potentiates cortical synapses (RWS-LTP) in vivo. An accumulation of postsynaptic AMPARs during similar sensory stimulation was also reported by imaging evidences. Our data demonstrates that this potentiation is occluded by SWE, suggesting that cortical synapses are already potentiated by this trimming protocol. This is translated into an increased neuronal excitability in the spared column and sensorimotor recovery by the spared whisker. To better understand the implication of LTP in cortical remapping, we developed a novel approach to manipulate LTP in vivo without affecting overall circuit properties. Our team showed previously that the blockage of AMPARs synaptic recruitment by extracellular antibody cross-linking prevents LTP in vitro. Here, we report that in vivo cross-linking of AMPARs blocks the expression but not the induction of RWS-LTP, suggesting that the synaptic recruitment of AMPARs is fundamental for in vivo LTP as well. Moreover, chronic AMPAR cross-linking during SWE reverts RWS-LTP occlusion and the increased neuronal excitability caused by whisker trimming. As consequence, the sensorimotor performance by the spared whisker is permanently impaired by the blockage of cortical remapping. Altogether, these evidences led us to define a critical role for synaptic LTP on circuit re-arrangement after whisker trimming. Our data shows that LTP-driven cortical remapping is a compensatory mechanism to optimize animal’s sensorimotor behavior upon altered sensory experience.Les champs récepteurs corticaux se réorganisent en réponse aux changements de l'environnement. Par exemple, suite à une lésion périphérique, les modalités sensorielles préservées gagnent de l'espace cortical au détriment de celles lésées. L'étude du cortex somatosensoriel en tonneau des rongeurs a fourni des données importantes pour la compréhension des mécanismes synaptiques à l'origine de cette réorganisation corticale. En condition normale, les neurones de chaque colonne corticale répondent préférentiellement à la stimulation d'une seule vibrisse principale ("Principal Whisker, PW"). Au contraire, suite à l'amputation de l'ensemble des vibrisses sauf une ("Single Whisker Experience, SWE"), les neurones des colonnes associées aux vibrisses amputées répondent à la stimulation de la vibrisse conservée, à l'origine du renforcement et de l'expansion des représentations corticales des vibrisses conservées. Bien que des preuves indirectes aient révélées un rôle de la potentialisation à long terme ("Long-Term Potentiation, LTP") de synapses préexistantes dans la modification des cartes corticales, probablement via une augmentation du nombre des récepteurs AMPA (AMPARs) aux synapses, un lien direct entre la LTP, la réorganisation des cartes corticales, et l'adaptation des comportements sensori-moteurs suite à une altération des entrées sensorielles n'a pas encore été démontré. L'objectif de cette thèse a donc été de mettre en évidence cette relation de façon expérimentale et en condition physiologique. Pour cela, nous avons mis au point une stratégie in vivo combinant des enregistrements électrophysiologiques, de l'imagerie biphotonique et l'analyse du comportement d'exploration chez la souris contrôle ("Full Whisker Experience, FWE) et amputée de certaines vibrisses (SWE). Nous avons d'abord confirmé que la stimulation rythmique de la PW ("Rhytmic Whisker Swtimulation, RWS") renforce les synapses excitatrices (RWS-LTP) in vivo des souris anesthésiées FWE. Au contraire des souris FWE, les neurones pyramidaux des souris SWE présentent une augmentation de l'excitabilité neuronale et une absence de RWS-LTP, indiquant ainsi que les synapses corticales associées à la vibrisse intacte ont été potentialisées en réponse au protocole SWE. Pour mieux comprendre l'implication de la RWS-LTP dans la réorganisation des cartes corticales et l'adaptation des comportements sensori-moteurs, nous avons développé une nouvelle approche pour manipuler la LTP in vivo grâce à l'immobilisation des AMPARs par des anticorps extracellulaires ("cross-linking"). En effet, notre équipe a montré précédemment que le cross-linking des AMPARs empêche la LTP in vitro. Par ailleurs, une accumulation des AMPARs au niveau post-synaptique a été démontrée in vivo par imagerie biphotonique au cours d'une stimulation RWS, suggérant un rôle de la mobilité de ces récepteurs dans cette RWS-LTP. Au cours de cette thèse, nous avons démontré que le cross-linking des AMPARs in vivo bloque également l'expression de la RWS-LTP, mais sans affecter la transmission synaptique basale, ni l'induction de la RWS-LTP, indiquant ainsi que la mobilité des AMPARs est également fondamental pour l'expression de la LTP in vivo. De façon importante, le cross-linking des AMPARs de façon chronique, au cours du SWE, permet non seulement de rétablir la RWS-LTP et l'excitabilité neuronale, et donc de bloquer la réorganisation corticale, mais aussi de modifier les capacités de récupération sensori-motrices des souris amputées. Dans l'ensemble, nos données démontrent pour la première fois un rôle critique et direct de la RWS-LTP dans le réarrangement des circuits en réponse à l'amputation de certaines vibrisses. La réorganisation des cartes corticales serait ainsi assurée par le renforcement de la transmission synaptique, et constituerait alors un mécanisme compensatoire pour optimiser le comportement sensorimoteur de l'animal lors de l'altération des entrées sensorielles
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