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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.
261

Pėdos raumenų elektrinis aktyvumas esant normaliai ir plokščiai pėdai / Electromyographic activity of foot muscles in subjects with normal and flat foot

Anužytė, Airė 10 September 2013 (has links)
Tyrimo objektas: Normalios ir plokščios pėdos raumenų elektrinis aktyvumas. Tyrimo tikslas: Nustatyti ir palyginti pėdos raumenų elektrinį aktyvumą esant normaliai ir plokščiai pėdai. Tyrimo uždaviniai: 1. Nustatyti ir palyginti atitraukiamojo kojos nykščio, priekinio blauzdos ir ilgojo šeivinio raumenų elektrinį aktyvumą stovint ant dviejų ir ant vienos kojos atpalaiduotoje ir neutralioje pašokikaulinio sąnario padėtyje esant normaliai pėdai. 2. Nustatyti ir palyginti atitraukiamojo kojos nykščio, priekinio blauzdos ir ilgojo šeivinio raumenų elektrinį aktyvumą stovint ant dviejų ir ant vienos kojos atpalaiduotoje ir neutralioje pašokikaulinio sąnario padėtyje esant plokščiai pėdai. 3. Palyginti atitraukiamojo kojos nykščio, priekinio blauzdos ir ilgojo šeivinio raumenų elektrinį aktyvumą stovint ant dviejų ir vienos kojos atpalaiduotoje ir neutralioje pašokikaulinio sąnario padėtyje tarp normalios ir plokščios pėdos. Tyrimo problema: Pėdos raumenys yra svarbūs išlaikant vidinį išilginį pėdos skliautą. Tačiau nėra žinoma ar skiriasi pėdos skliautą išlaikančių raumenų aktyvumas esant normaliai ir plokščiai pėdai. Išvados: 1. Esant normaliai pėdai atitraukiamasis kojos nykščio raumuo aktyviausias stovint ant vienos kojos neutralioje pašokikaulinio sąnario padėtyje (p<0,05), ilgasis šeivinis raumuo – stovint ant vienos kojos atpalaidavus (p<0,05). Statistiškai reikšmingo priekinio blauzdos raumens elektrinio aktyvumo pokyčių nenustatyta. 2. Esant plokščiai pėdai... [toliau žr. visą tekstą] / Object of the research: electromyographic activity of the normal and flat foot muscles. The aim of the research: To evaluate and compare electromyographic activity of foot muscles in subjects with normal and flat foot. The tasks of the research: 1. To evaluate and compare electromyographic activity of abductor hallucis, tibialis anterior and peroneus longus musles standing on two or one leg in relaxed and subtalar neutral position in subjects with normal foot. 2. To evaluate and compare electromyographic activity of abductor hallucis, tibialis anterior and peroneus longus muscles standing on two or one leg in relaxed and subtalar neutral position in subjects with flat foot. 3. To compare electromyographic activity of abductor hallucis, tibialis anterior and peroneus longus muscles standing on two or one leg in relaxed and subtalar neutral position between subjects with normal and flat foot. Problem of the research: Intrinsic and extrinsic foot muscles are important supporting medial longitudinal arch. However, there is no research about foot muscle activity in subjects with different foot types. Conclusions: 1. In subjects with normal foot the greatest electromyographic activity of abductor hallucis was standing on one leg in neutral subtalar joint position (p<0,05), the greatest activity of peroneus longus – standing on one leg in relaxed subtalar joint position (p<0,05). There were no significant differences in electromyographic activity of tibialis anetrior. 2. In... [to full text]
262

Papel do cortex pré-frontal medial no comportamento defensivo de camundongos : avaliação farmacológica da lateralização funcional

Costa, Nathália Santos 13 April 2017 (has links)
Submitted by Ronildo Prado (ronisp@ufscar.br) on 2017-08-23T19:35:48Z No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-23T19:35:55Z (GMT) No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-08-23T19:36:03Z (GMT) No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) / Made available in DSpace on 2017-08-23T19:36:10Z (GMT). No. of bitstreams: 1 DissNSC.pdf: 1757369 bytes, checksum: 8c5c3122b8536a2aa61fd673039785e3 (MD5) Previous issue date: 2017-04-13 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Stressful situations are risk factors to the development of neuropsychiatric diseases, as anxiety disorders. However, not everyone who experiences stressful events develops stress-related illness. That is due to the existence of differences in the ability to adapt to stress, that is, the manifestation of susceptibility or resilience phenotypes. The search for understanding neural systems involved to these differences has evidenced an important role of the medial Prefrontal Cortex (mPFC), and, recently, its functional lateralization has been highlighted. In this sense, the right mPFC (RmPFC) seems to modulate anxiogenic-like responses, while the left mPFC (LmPFC) would attenuate such responses, thereby facilitating animals to cope with threatening situations. If so, LmPFC inhibition would intensify ansiogenic-like behavior front to aversive stimuli. Under this hypothesis, one of the goals of the present study was to investigate whether the inhibition of the LmPFC could modulate the effect of two types of stress (the restraint and the social defeat) on anxiety. Yet, we also aimed to investigate whether NMDA-glutamate receptor would be involved to the anxiogenic-like effect induced by nitrergic activation of the RmPFC, given the anxiogenic potential of glutamate and the interaction already known between these neurotransmissions. To reach that, experiments were carried out (1) to characterize the effects of social defeat and restraint stress on animals exposed to elevated plus maze (EPM) 5 minutes or 24 hours later; (2) to evaluate the effects of restraint or social defeat combined to the synaptic inactivation (through nonspecific inhibitor, CoCl2) of the LmPFC on the defensive behavior of mice exposed to EPM 24 h after stress; (3) to investigate the effects of NMDA receptor antagonism and (4) the effect of that antagonism on anxiogenic-like effects induced by NO donor. The results showed that both restraint and defeat stress are anxiogenic at 5 minutes, but defeated mice do not display anxiety 24 h after stress. Furthermore, the synaptic inhibition produced a clear anxiogenic-like effect in defeated (but not restrained) mice. In addition, the blockade of NMDA receptors produced anxiolytic-like effects and reversed the anxiogenic effect induced by NO injection into the RmPFC. Taken together, these results corroborate previous studies demonstrating the functional lateralization of the mPFC, in which the right and left hemispheres seem to have distinct roles in the modulation of aversive events. / O estresse, que pode ser definido como uma condição que perturba o equilíbrio fisiológico e psicológico de um indivíduo, é fator de risco para o desenvolvimento de doenças neuropsiquiáticas, como transtornos de ansiedade. No entanto, nem todos os indivíduos que vivenciam um evento estressor desenvolvem doenças relacionadas a ele. Isto se deve à existência de diferenças na habilidade de se adaptar ao estresse, ou seja, a manifestação dos fenótipos de susceptibilidade ou resiliência. A busca pelo entendimento dos sistemas neurais envolvidos nessas diferenças tem evidenciado um papel importante do Córtex Pré-Frontal medial (CPFm) e, mais recentemente, a sua lateralização funcional vem ganhando especial destaque. Neste sentido, o CPFm Direito (D) parece modular respostas ansiogênicas, enquanto o CPFm Esquerdo (E) atenuaria essas respostas, ajudando o animal a lidar com eventos aversivos. Neste caso, a inibição do CPFmE intensificaria as respostas geradas por situações ameaçadoras. Sob essa hipótese, um dos objetivos do presente trabalho foi investigar se a inibição do CPFmE poderia modular o efeito de dois tipos de estresse (a contenção e a derrota social) sobre a ansiedade. Ainda, esse estudo também investigou se os receptores glutamatérgicos do tipo NMDA (N-metil-D-aspartato) estariam envolvidos no efeito ansiogênico provocado pela ativação nitrérgica [com injeção local do doador de óxido nítrico (NO), o NOC-9] no CPFmD, haja vista o potencial ansiogênico do glutamato e as interações já conhecidas entre essas neurotransmissões. Para tanto, foram feitos experimentos para (1) caracterizar os efeitos imediatos (após 5 minutos) ou tardios (após 24 horas) do estresse de derrota social e de contenção sobre o comportamento de animais expostos ao labirinto em cruz elevado (LCE); (2) avaliar os efeitos da combinação do estresse de contenção ou de derrota social com a inativação sináptica (através do inibidor inespecífico, CoCl2) do CPFm E no comportamento defensivo de camundongos expostos ao LCE 24h após o evento estressor; (3) investigar os efeitos do antagonismo per se de receptores NMDA e (4) o efeito desse antagonismo sobre a ansiogênese provocada pelo doador de NO sobre o comportamento de animais expostos ao LCE. Os resultados obtidos demonstram que ambos os estressores são ansiogênicos aos 5 minutos, mas a derrota social não provoca aumento de ansiedade 24 h após o estresse. Ainda, a inbição sináptica do CPFmE produz efeito ansiogênico 24 h depois quando associada ao estresse de derrota social (mas não à contenção). Além disso, o bloqueio de receptores NMDA por si provoca efeito ansiolítico e reverte o efeito ansiogênico provocado pelo NO em animais expostos ao LCE. Tomados em conjunto, esses resultados substanciam as evidências sobre a lateralização funcional do CPFm, em que os hemisférios direito e esquerdo parecem possuir diferentes participações na modulação de eventos aversivos.
263

Vogais postônicas não-finais: do sistema ao uso

Silva, André Pedro da 21 June 2010 (has links)
Made available in DSpace on 2015-05-14T12:43:28Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2125510 bytes, checksum: aa04eddf6c4ebfdab57270cd91d4cd05 (MD5) Previous issue date: 2010-06-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This paper describes the behavior of variable medial post-stressed vowel in nouns, in the dialect of the town of Sapé, located in the state of Paraiba. In this context, there were done two analyses. The first one is a variationist, in order to verify the effects of deletion of the medial post-stressed vowel, and compare the results with other studies of similar nature. To do so, we adopted the theoretical basis in Labov (1972) and Weinreich; Labov; Herzog (1968). The second analysis, phonological character, focused on analyzing the processes triggered either by resistance to syncope - the raising and rounding of the medial post-stressed vowels, based on Câmara Jr. (2002 [1970]) and Battisti; Vieira (2005) the former one is an occurrence of syncope: assimilation, resyllabification and restructuring of the feet, from two theoretical models Metrical Phonology: The Selkirk (1982) on the syllable, and Hayes (1995) on the accent. Under the Sociolinguistics Variation point of view, one analyzed statistically, linguistic and social variables that favor the deletion of the medial post-stressed vowel. The results were compared to those of other studies that aimed to investigate the same phenomenon, but with speech data from other regions of Brazil. It was found that the fact of year of schooling is the most important one in the medial poststressed vowels deletion in three out of four works under study, as well as the following phonological context, which was considered the most conducive to the process focused on this study. But Amaral (1999) and Lima (2008) state that the liquid vibrant is the most vibrant favoring the process of deletion, while Silva (2006) and Ramos (2009), state that the liquid side is the one. Thus, after the erasure process it occurs medial post-stressed vowel, the consonantal segment remaining after the deletion is incorporated herein to the stressed syllable, either to attack the unstressed final syllable, through resyllabification, causing a restructuring of syllabic feet, transforming them into penultimate stressed words as, respectively: música ~ musca and xícara ~ xicra. whenever this deletion does not occur, the medial post-stressed vowels [e] and [o] face prosecution for opening, for example, in a.bó.b[o].ra ~ a.bó.b[o].ra, and revolt in ár.v[o].re ~ ár.v[o]re. It is through this process of assimilation that a segment assimilates characteristics of the previous segment, as in física ~ [fizga], and/or segment, as in música ~ [musca]. / O presente trabalho descreve o comportamento variável das vogais postônicas mediais, em nomes, no dialeto da cidade de Sapé, localizada no interior do estado da Paraíba. Nesse contexto, objetivaram-se duas análises: uma variacionista, a fim de verificar os efeitos do apagamento da vogal postônica medial e comparar os resultados com outros estudos de mesma natureza. Para tanto, foram adotadas as propostas teóricas de Labov (1972) e de Weinreich, Labov e Herzog (1968). A segunda análise, de caráter fonológico, visou analisar os processos desencadeados ora pela resistência à síncope o alçamento e o arredondamento das vogais postônicas mediais, a partir da discussão de Câmara (2002 [1970]) e de Battisti e Vieira (2005) ora pela ocorrência da síncope: assimilação, ressilabação e reestruturação dos pés, a partir de dois modelos teóricos da Fonologia Métrica: o de Selkirk (1982), sobre sílaba, e o de Hayes (1995), sobre o acento. Sob a égide da Sociolinguística Variacionista, analisaram-se, estatisticamente, as variáveis linguísticas e sociais que favorecem o apagamento da vogal postônica medial. Os resultados foram comparados com os de outros trabalhos que tiveram por objetivo investigar o mesmo fenômeno, porém com dados de fala de outras regiões do Brasil. Constatou-se que o fator ano de escolarização é o mais relevante no processo de apagamento da vogal postônica medial em três dos quatro trabalhos em estudo, assim como o contexto fonológico seguinte, que foi tido por todos como sendo o mais propício ao processo aqui em estudo. Porém Amaral (1999) e Lima (2008) apontam a líquida vibrante como a mais favorecedora do processo de apagamento, ao passo que Silva (2006) e Ramos (2009), a líquida lateral. Assim sendo, depois de ocorrer o processo de apagamento da postônica medial, o segmento consonantal restante após o apagamento é incorporado ora à sílaba tônica, ora ao ataque da sílaba átona final, por meio da ressilabação, o que provoca uma reestruturação dos pés silábicos, transformando-as em palavras paroxítonas, como, respectivamente, em: música ~ musca e xícara ~ xicra. Quando não ocorre esse apagamento, as vogais [e] e [o] postônicas mediais sofrem processos de abertura, como por exemplo, em a.bó.b[o].ra ~ a.bó.b[o].ra, e de alçamento, em ár.v[o].re ~ ár.v[o].re. É por esse processo de assimilação que um segmento assimila características do segmento precedente, como em fizica ~ fizga, e/ou do segmento seguinte, como em música ~ musca.
264

Heterogeneous Object Modelling : Representation, Construction and Process Planning

Sharma, Gaurav Kumar January 2015 (has links) (PDF)
Heterogeneous Objects are engineered with multiple materials to achieve multiple functionalities like high hardness, high toughness and low structural weight. Heterogeneous objects are increasingly used to achieve multiple and often conflicting behaviour within a single object. Developing heterogeneous objects needs computational model for design, analysis and manufacturing. The computational model should map the geometry of the object with the material composition. The most general model is the volume based model that decomposes the geometry exhaustively into simple elements and defines the material distribution over these elements. This approach can model a wide range of objects. However, defining material distribution needs manual intervention to select these elements for material continuity, and to segment or subdivide them for better material approximation. Volume based representation is quite large in size and is cumbersome to edit, query or reuse. Feature based approaches have been proposed to address some of these issues. However, current art can model only limited class of Heterogeneous Objects that includes simple material distribution over complex geometry or complex material distribution over simple geometry. The thesis presents a new method to overcome these limitations. The method, a hybrid of volume based and feature based approaches, allows the user to define the complex material distribution over complex geometries intuitively and represent the same. The complex material distribution is modelled using material reference entities that may be mixed-dimensional, inclusive of non-manifold entities. It uses Medial Axis Transform for automated segmentation of these entities into independent regions, where the material distribution can be intuitively prescribed starting from the entity and terminating at the medial axis. The spatial variation of the material is captured by a parameterized distance field from the material reference entities. It develops new constructive operators to build a complex heterogeneous object model that allows the reuse of the existing heterogeneous object models, automates handling of material continuity, and controls the gradation of the material in the interface of the constituent heterogeneous objects. Constructions using these operators can be geometry driven or material driven i.e. the geometric form controls the material distribution or the material distribution is independent of the geometric form. The proposed representation can be adaptively meshed for generation of mesh in the direction of gradation of the material for finite element analysis and process planning for additive manufacturing. An iso-material contour representation has been proposed for process planning of Heterogeneous Object Models. This avoids the stair case effect by depositing material in the direction of material gradation, and avoids over-deposition or under-deposition due to frequent start and stop of the nozzles. The proposed method has been implemented to show that it can model wide range of heterogeneous objects and can be integrated with additive manufacturing.
265

Role of the ventromedial hypothalamus in control of innate defensive behaviours

Wroblewska, Natalia January 2018 (has links)
Our senses are constantly bombarded with information. How does the brain integrate such a variety of inputs to generate appropriate behaviours? Innate defensive behaviours are a good model to address this question. They are essential for animal survival and the brain circuits that control them are highly conserved across species. Moreover, the sensory inputs and behavioural outputs can be well defined and reliably reproduced in the lab. This allows us to study function of the individual components of the circuit controlling these behaviours. Ventromedial hypothalamus (VMH) is a key brain region for controlling responses to predators; it has been shown that inactivating the VMH can reduce defensive behaviours. Interestingly, activating the VMH output neurons (SF1+ cells) can produce a variety of different behaviours, from immobility to escape, depending on the intensity of activation. During my PhD I used a variety of approaches to address the question of the function of the VMH in control of defensive behaviours. At first I hypothesised that the VMH might act as a centre responsible for choosing an appropriate behavioural response according to the stimulus. I set to investigate how different activation levels of SF1+ neurons can produce such different behavioural outputs, and how this activity is modulated in vivo in response to predator stimuli. I began the project by quantifying mouse defensive behaviours in response to olfactory and auditory predator cues, as well as to the optogenetic activation of SF1+ neurons. I then questioned whether there was heterogeneity within the population of SF1+ neurons, which could explain their ability to trigger different behaviours. I performed patch clamp recordings from acute brain slices and conducted a study of the electrophysiological properties of SF1+ neurons. I next investigated how SF1+ neurons integrate excitatory inputs from the medial amygdala, a region which receives olfactory inputs from the accessory olfactory bulb. By combining optogenetics with slice electrophysiology and behavioural assessment, I described the physiology and relevance of this connection. Finally, I investigated in vivo activity in the VMH in response to predator cues by performing calcium imaging of the VMH neurons in freely moving mice. By presenting different sensory stimuli, I addressed the question of heterogeneity of the input pattern to the VMH neurons and the relationship between the VMH activity and the behavioural output. Taken all together, the results of this project have led to a hypothesis whereby the function of the VMH is to facilitate rather than directly control the choice of an appropriate behavioural response.
266

Síndrome da dor femoropatelar análise eletromiográfica, isocinética, ressonância magnética, dor e fadiga.

Souza, Alessandra de Castro 22 March 2005 (has links)
Made available in DSpace on 2016-06-02T20:18:25Z (GMT). No. of bitstreams: 1 TeseACS.pdf: 1629824 bytes, checksum: 9ffe05e7af325db5e778585c64e4910a (MD5) Previous issue date: 2005-03-22 / Universidade Federal de Sao Carlos / The purpose of this work was to analyze the electrical activity (EMG) of the vastus medialis obliquus (VMO) and vastus lateralis longus (VLL) and vastus lateralis obliquus (VLO) in association with the evaluation of the maximum isometric torque (MIT) of the quadriceps muscle, during the maximum voluntary isometric contraction (MVIC) of knee extension in open kinetic chain (OKC) at 20o, 30o, 50o and 60o of knee flexion, also, pain and fatigue and the aspects in relation to patellae positioning: the sulcus angle (SA), the congruence angle (CA), patellar tilt angle (PTA) and lateral patellar displacement (LDP). Twenty four female subjects were evaluated (12 with patellofemoral pain syndrome PFPS and 12 clinically normal controls). For the EMG analysis simple surface differential active electrodes and a Signal Conditioner Module (MCS 1000-v2) were used. The electromyographic signal was quantified by the Root Mean Square (RMS), in µV, and normalized by the MVIC of 90o of knee extension. The subjects made 5 MVIC of knee extension, at 30o of flexion for the EMG and MMIT analysis and the NMRI with the quadriceps muscle relaxed were obtained at the same angles. The following statistic tests were used: ANOVA Analysis of Variance with Repeated Measurements for the EMG and MMIT analysis; the Mann-Whitney U test for the NMRI; and the One Way Analysis of Variance for the evaluation of intensity and discomfort from pain and fatigue (p &#8804; 0.05). The results showed a higher electrical activity of the VLL muscle in relation to the VMO in the group with FPPS. The control group, the VMO and VLL did not present a significant difference in all studied angles. In both groups, VMO and VLL showed a higher electrical activity in comparison with VLO, in all angles. The MMIT values of the quadriceps did not differ among groups, however it did differ between angles. The highest MMIT value was 60o. The NMRI analysis revealed that the FPPS group presented higher values of SA and lower values of CA in relation to the Control group. The results showed an increase in pain and fatigue of the subjects with PFPS after the MVIC and in comparison with the Control group. The data of this study, on the experimental conditions, suggest that: a higher electrical activity of the VLL in addition with the increase in SA and decrease in CA in the subjects with PFPS can be factors favoring such individuals patellar instability. Pain and fatigue were greater in subjects with PFPS. The results showed that the EMG and the NMRI were instruments capable of differentiating the groups that were studied. / A proposta deste estudo foi analisar a atividade elétrica (EMG) dos músculos vasto medial oblíquo (VMO), vasto lateral longo (VLL) e vasto lateral oblíquo (VLO) associada à avaliação do torque isométrico máximo (TIM) do músculo quadríceps, durante contração isométrica voluntária máxima (CIVM) de extensão de joelho em cadeia cinética aberta (CCA) a 20o, 30o, 50o e 60o de flexão de joelho, juntamente com a análise da intensidade e desagradabilidade da dor e fadiga muscular; e os parâmetros de posicionamento da patela: Ângulo do Sulco (AS), Ângulo de Congruência (AC), Ângulo de Inclinação Patelar (AIP) e Deslizamento lateral da patela (DLP). Foram avaliadas 24 voluntárias, do sexo feminino, entre 18 e 34 anos (22,52 ± 3,94), sedentárias, que segundo critérios de inclusão e exclusão, avaliando os sinais e sintomas, foram classificas como sendo: 12 portadoras de Síndrome da Dor Femoropatelar, sintomáticas e as outras 12 consideradas clinicamente Normais. Para análise da EMG, foram utilizados eletrodos ativos diferenciais simples de superfície, com um ganho de 100 vezes e um Módulo Condicionador de Sinais (MCS 1000-v2), com ganho de 10 vezes. Os sinais eletromiográficos foram amostrados de forma sincrônica, analisados por meio do Root Mean Square RMS (µV) e normalizados pela CIVM extensão do joelho à 90 graus. Utilizou-se um dinamômetro isocinético para o registro do Torque Isométrico Máximo (TIM), um equipamento de Ressonância Magnética Nuclear por Imagem (RMNI) para verificar os posicionamentos da patela e uma escala visual analógica (EVA) para analise da dor e fadiga muscular, em mm. Os indivíduos realizaram 5 CIVM de extensão de joelho nos ângulos de 20o, 30o, 50o e 60o de flexão para análise da EMG e do TIM. A 30o de flexão de joelho, foram realizadas as RMNI com músculo relaxado. Foram utilizados os testes estatísticos: ANOVA - Análise de Variância de Medidas Repetidas para analisar a EMG e o TIM; o teste Mann-Whitney U para análise da RMNI e Análise de Variância One Way para avaliação da intensidade e desagradabilidade de dor e fadiga muscular (p &#8804; 0,05). Os resultados evidenciaram maior atividade elétrica do músculo VLL em relação ao VMO, no grupo com SDFP, enquanto que no grupo Controle, os músculos VMO e VLL não apresentaram diferença significativa entre si, em todos os ângulos estudados. Em ambos os grupos, os músculos VMO e VLL apresentaram maior atividade elétrica que o VLO, em todos os ângulos. Não houve diferença significativa do TIM entre os 2 grupos, mas sim entre os ângulos e o maior valor do TIM foi a 60 graus. A análise da RMNI revelou que o grupo com SDFP apresentou maiores valores do AS e menores do AC em relação ao grupo Controle. Os resultados mostraram ainda um aumento da dor e da fadiga nos indivíduos com SDFP após as CIVM quando comparar ao grupo Controle. Os dados desta pesquisa, nas condições experimentais utilizadas, sugerem que: uma maior atividade elétrica do VLL juntamente com o aumento do AS e a diminuição do AC nos indivíduos com SDFP, poderiam ser considerados como fatores que predispõem a instabilidade patelar destes indivíduos. A dor e a fadiga foram maiores nos indivíduos com SDFP. Os resultados revelaram que tanto a EMG quanto a RMNI foram instrumentos capazes de diferenciar os grupos estudados.
267

Efeito imediato da estimula??o el?trica neuromuscular seletiva do m?sculo VMO em pacientes com s?ndrome da dor femoropatelar

Augusto, Denise Dal'ava 13 April 2010 (has links)
Made available in DSpace on 2014-12-17T15:16:08Z (GMT). No. of bitstreams: 1 DeniseDA_DISSERT.pdf: 659589 bytes, checksum: a95e9f3f95d4524998e52ab9a5dd9577 (MD5) Previous issue date: 2010-04-13 / Patellofemoral pain syndrome (PFPS) is described as anterior or retropatellar pain knee in the absence of other pathologies and is frequently associated with dysfunction of the vastus medialis oblique (VMO). However, several studies have demonstrated the inability to selectively activate this muscle through exercise. To evaluate the effect of Neuromuscular Electrical Stimulation (NMES) selective VMO in women with syndrome. We evaluated thirty-eight women: twenty in the control group (24.15 ? 2.60 years) and eighteen diagnosed with PFPS (25.56 ? 3.55 years). Both groups were evaluated before and after a protocol of electro stimulation. To measure for comparing groups before and after treatment, we assessed the extensor torque concentric and eccentric knee through an isokinetic dynamometer, the intensity (Root Mean Square - RMS) and the onset of activation (onset) of VMO compared to the vastus lateralis (VL) in two types of exercise: open and closed kinetic chain. . Statistical analysis was performed using SPSS 15.0, with a significance level of 5%. Results: Our data showed an increase in the intensity of activation (RMS) of the VMO muscle after NMES in both study groups. During concentric contraction the RMS of the VMO before the NMES was 105.69 ? 32.26 &#956;V and after a single intervention was 122.10 ? 39.62 &#956;V (p = 0.048) for the control group. In the group with PPS, we found a similar behavior, with RMS of the VMO before NMES of 96.25 ? 18.83 &#956;V and 139.80 ? 65.88 &#956;V after the intervention (p = 0.0001). However, there was no evidence in the RMS value of VL muscle. The onset was calculated by subtracting the onset of VL by the onset of VMO. For the group with PFPS, the onset before the intervention was -0.007 ? 0.14 ms, indicating a delay of the VMO relative to VL, and after NMES was 0.074 ? 0.09 ms (p = 0.016), showing an activation previous VMO to VL. The same occurred for the control group. We also observed that NMES increased knee extensor power during the concentric contraction in both groups. Before the intervention the mean power was 28.97 ? 9.01 W for the PPS group and after NMES was 34.38 ? 7.61 W (p = 0.0001). Conclusion: We observed an increase in electromyographic activity of the VMO and also an anticipatory effect of this muscle / A S?ndrome da Dor Femoropatelar (SDFP) ? freq?entemente associada ? disfun??o do Vasto Medial Obl?quo (VMO). Diversos estudos t?m demonstrado a impossibilidade de ativar seletivamente este m?sculo por meio de exerc?cios. Avaliar os efeitos de uma ?nica sess?o de Estimula??o El?trica Neuromuscular (EENM) seletiva do m?sculo VMO, em sujeitos com SDFP. Foram avaliadas 38 mulheres sendo 20 pertencentes ao grupo controle (24,15 ? 2,60 anos) e 18 com diagn?stico de SDFP (25,56 ? 3,55 anos). Ambos avaliados antes e ap?s um protocolo de eletroestimula??o. Para medida de compara??o dos grupos antes e depois do tratamento, foram avaliados, o desempenho isocin?tico, a intensidade de ativa??o muscular (Root Mean Square RMS) e o in?cio da ativa??o (onset) do VMO comparado ao vasto lateral (VL). Para an?lise estat?stica foi utilizado o programa SPSS 15.0, com um n?vel de signific?ncia de 5%. Resultados: Nossos dados mostraram um aumento na intensidade de ativa??o (RMS) do m?sculo VMO ap?s a EENM, em ambos os grupos de estudo. Durante a contra??o conc?ntrica o RMS do VMO antes da EENM foi 105,69 ? 32,26 &#956;V e depois de uma ?nica interven??o foi de 122,10 ? 39,62 &#956;V (p=0,048) para o grupo controle. No grupo com SDFP, encontramos um comportamento semelhante, com RMS do VMO antes da EENM de 96,25 ? 18,83 &#956;V e 139,80 ? 65,88 &#956;V depois da interven??o (p=0,0001). Entretanto, n?o foi evidenciada altera??o no valor RMS do m?sculo VL. O onset foi calculado atrav?s da subtra??o do onset do VL pelo onset do VMO. Para o grupo com SDFP, o onset antes da interven??o foi de -0,007 ? 0,14 ms, evidenciando um atraso do VMO em rela??o ao VL, e ap?s a EENM foi 0,074 ? 0,09 ms (p=0,016), mostrando uma ativa??o do VMO anterior ao VL. O mesmo ocorreu para o grupo controle. Observamos tamb?m que a EENM aumentou a pot?ncia extensora do joelho, durante a contra??o conc?ntrica em ambos os grupos. Antes da interven??o a m?dia da pot?ncia era de 28,97 ? 9,01 W para o grupo SDFP e depois da EENM foi de 34,38 ? 7,61 W (p=0,0001). Conclus?o: Observou-se um aumento na atividade eletromiogr?fica do VMO ap?s a eletroestimula??o, al?m de um efeito antecipat?rio deste m?sculo
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Mediação do medo condicionado contextual por mecanismos serotoninérgicos do circuito núcleo mediano da rafe-hipocampo dorsal / Serotonergic mechanisms of the median raphe nucleusdorsal hippocampus in conditioned fear: Output circuit involves the prefrontal cortex and amygdala

Rafael Carvalho Almada 18 May 2009 (has links)
Vários estudos mostram que o núcleo mediano da rafe (NMR) e o hipocampo dorsal (HD) estão envolvidos no medo condicionado Pavloviano. Além disso, mecanismos serotoninérgicos do NMR parecem participar da expressão da resposta de medo condicionado contextual. Entretanto, ainda não existe uma abordagem experimental que integre os mecanismos do circuito NMR-HD. Neste trabalho, o paradigma do medo condicionado foi utilizado para testar a influência dos mecanismos serotoninérgicos do circuito NMR-HD no medo condicionado contextual. As respostas de sobressalto e congelamento foram avaliadas após a administração de drogas serotoninérgicas intra-NMR e no HD, 6 h depois a sessões treino, nas quais os ratos eram condicionados com choques nas patas. A redução da transmissão serotoninérgica no NMR é devido a microinjeção do 8-hidroxi-2(di-n-propilamino)-tetralin (8-OH-DPAT), um agonista de receptores 5-HT1A, no NMR promoveu redução das respostas de congelamento, mas não alterou a resposta de sobressalto. Estes resultados são consistentes com a ideia de que mecanismos serotoninérgicos no NMR regulam as respostas de congelamento a um contexto aversivo. A diminuição pós-sináptica da serotonina nas áreas de projeção do NMR ocorre devido a ativação de autoreceptores 5-HT1A nesta estrutura. Com relação ao hipocampo, a microinjeção de cetanserina, um antagonista de receptores 5-HT2, não promoveu alteração nas respostas de congelamento e sobressalto potencializado pelo medo, porém a ativação de receptores 5-HT1A pela injeção de 8-OH-DPAT 6 h após o treino inibiu essas respostas. De acordo com esses resultados, um mecanismo inibitório deva se interpor entre os processos associados à chegada de informação aversiva e os associados à saída delas no HD. As projeções HD-amígdala e córtex pré-frontal medial podem constituir a porta de saída dos processos neurais subjacentes a expressão do medo condicionado contextual, conforme foi observado no experimento em que estudou a imunorreatividade destas estruturas á proteína Fos em ratos submetidos ao mesmo procedimento experimental de medo condicionado contextual / Several studies have shown that the median raphe nucleus (MRN) and dorsal hippocampus (DH) are involved in Pavlovian conditioned fear. Moreover, previous findings have also implicated serotonergic mechanisms of the MRN in the retrieval of contextual conditioned fear. However, studies that examine the integrated involvement of serotonergic mechanisms of the MRN-DH are lacking. This study, a fear conditioning paradigm was used to test whether the serotonergic projections from the MRN to DH can influence contextual fear conditioning. Startle and freezing responses were avaliated after administration of serotoninergics drugs into the MRN or DH, 6 h previously rats received footshocks in the training session. A reduction of 5-HT transmission in the MRN by local infusions of the 5-HT1A agonist 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT) decreased freezing in response to the CS but did not reduce fear-potentiated startle. This pattern of results is consistent with the hypothesis that MRN serotonergic mechanisms selectively modulate the freezing response to the aversive context. As for the DH, a decrease in postsynaptic 5-HT receptor activity at projection areas has been proposed to be the main consequence of 5-HT1A receptor activation in the MRN. Infusions of the 5-HT2 receptor antagonist ketanserin into the DH had no effect, but activation of 5-HT1A receptors through intra-DH injections of 8-OH-DPAT inhibited both the freezing and fear-potentiated startle response to the CS. To reconcile these findings, an inhibitory mechanism may exist between the incoming DH 5-HT pathway from the MRN and the presynaptic 5-HT neurons that are part of the DH output to other structures. The DH-amygdala and medial prefrontal cortex projections could well be this output circuit modulating the expression of contextual fear conditioning as revealed by measurements of Fos immunoreactivity in these areas.
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Fatores preditivos de resultados desfavoráveis da meniscectomia medial artroscópica em pacientes com mais de 50 anos de idade / Predictors of poor outcomes of arthroscopic medial meniscectomy in patients over 50 years old

Alexandre de Christo Viegas 19 February 2015 (has links)
A evolução do conhecimento acerca das funções dos meniscos e do tratamento das suas lesões, impulsionada pelo advento da cirurgia artroscópica, consagrou e popularizou a meniscectomia por esta via, por ser uma técnica menos invasiva, com menor morbidade e menores custos hospitalares, a ponto de torná-la, atualmente, a cirurgia ortopédica mais frequentemente realizada no mundo. Embora a maior parte dos pacientes submetidos a esta intervenção cirúrgica tenha resultados favoráveis e resolução rápida dos sintomas, percebe-se que parte considerável dos pacientes, especialmente os mais idosos, não apresenta uma evolução póscirúrgica satisfatória, apresentando piora dos sintomas e, eventualmente, necessitando de nova cirurgia. Partindo da hipótese que em determinados pacientes a meniscectomia, em vez de tratar, precipita e acentua um desequilíbrio biomecânico do joelho, o autor realizou estudo observacional prospectivo não-controlado com 86 pacientes de ambos os gêneros, com idade superior a 50 anos (média de 60,2 ± 7,1 anos), submetidos à meniscectomia artroscópica para tratamento de lesão do menisco medial de natureza degenerativa, com o objetivo de determinar variáveis demográficas, clínicas, anatômicas e cirúrgicas relacionadas aos resultados desfavoráveis. As avaliações funcionais pré e pós-operatórias foram realizadas utilizandose o Índice do KOOS (Knee Injury and Osteoarthritis Outcome Score), aplicado a todos os pacientes antes da cirurgia e 60 meses depois. Após análise estatística dos resultados obtidos, o autor verificou que 10 fatores podem ser considerados preditivos das meniscectomias mediais artroscópicas neste grupo etário, sendo quatro fatores fortemente associados aos resultados desfavoráveis: lesão da raiz posterior do menisco medial, dor pré-operatória intensa, claudicação antes da cirurgia e tempo decorrido entre o início dos sintomas e a cirurgia; dois fatores foram considerados moderadamente associados aos resultados desfavoráveis: presença de edema de medula óssea na ressonância magnética (RM) préoperatória e duração da cirurgia; quatro fatores foram considerados associados de modo fraco aos resultados desfavoráveis: Índice de Massa Corporal (IMC) >= 30 kg/m2 , varismo do joelho, presença de cisto poplíteo na RM pré-operatória e extensão da ressecção do menisco medial / The evolution of knowledge concerning meniscal functions and the treatment of their injuries, boosted by the development of arthroscopic surgery, has established and popularized arthroscopic meniscectomy due to its less invasiveness, less post-operative morbidity and lower hospital costs, to the point it has become, nowadays, the most frequently performed orthopedic procedure in the world. Although the majority of patients undergoing this operation is quite pleased with the outcomes and with the prompt resolution of their symptoms, it is noticeable that a considerable amount of patients with meniscal injuries, mainly the older, does not have a satisfactory postoperative outcome, with worsening of symptoms after being operated on and occasionally requiring another surgery. Based on observations of his medical practice and on the assumption that meniscectomy, rather than treat, can hasten and accentuate a biomechanical imbalance of the knee in those patients, the author conducted an observational prospective uncontrolled study with 86 patients of both genders, aged over 50 years old (average 60.2 ± 7.1 years), who underwent arthroscopic meniscectomy for the treatment of degenerative medial meniscal lesions, aiming to determine demographic, anatomical, clinical and surgical variables related to poor outcomes. The functional pre and post-operative evaluations were performed using the KOOS index (Knee Injury and Osteoarthritis Outcome Score) applied to all patients before surgery and 60 months later. After statistical analysis of the results, the author found that 10 factors can be considered predictors of arthroscopic medial meniscectomy in this age group: four factors were strongly associated with unfavorable results - posterior root lesion of the medial meniscus, intense pre-operative pain, claudication before surgery and time elapsed between onset of symptoms and surgery; two factors were moderately associated with unfavorable results - bone marrow edema in preoperative magnetic resonance imaging (MRI) and surgery time length; four factors that were weakly associated with poor results - bone mass index (BMI) >= 30 kg/m2, varus knee, poplyteal cyst in pre-operative MRI and extension of meniscal ressection
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Implication de l’habénula latérale dans les processus mnésiques chez le rat / Involvement of the lateral habenula in memory processes in rat

Mathis, Victor 08 December 2016 (has links)
Ce travail de thèse avait pour objectif d’étudier le rôle de l’habénula latérale (HbL) dans les processus mnésiques chez le Rat en utilisant une approche par inactivation réversible grâce à l’administration de muscimol ou de CNQX. Nous avons ainsi montré l’implication de l’HbL dans : i) les processus d’encodage et de rappel d’une mémoire spatiale en piscine de Morris ; ii) la mémoire de travail, comme relais potentiel d’informations en provenance du cortex préfrontal médian, dans un paradigme de non-appariement différé à la position en boites de conditionnement opérant; iii) la réponse émotionnelle, aux niveaux comportemental et physiologique, à une situation stressante. L’ensemble de ces résultats suggèrent que l’HbL est impliquée dans les processus « online » de gestion des informations sensorielles, et qu’elle participe à la prise en compte de l’aspect émotionnel d’une situation. Ces particularités en font un lien important potentiel entre gestion des émotions et cognition. / The main objective of this thesis was to investigate the role of the lateral habenula (LHb) in mnemonic processes in rats using reversible inactivations with muscimol or CNQX. We have shown the involvement of the LHb in : i) encoding and retrieval of spatial reference memory in the Morris water maze ; ii) working memory, as a potential relay of top-down information coming from the medial prefrontal cortex, in a delayed non-matching to position paradigm using operant chambers ; iii) the behavioral and physiological responses to stressful situations. Altogether, those results suggest that the LHb is involved in the « online » process of sensory information. They also suggest that it is involved in coping with particularly stressful situations, and further position the LHb as an interface between emotions and cognition.

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