O objetivo desta pesquisa foi comparar o desempenho - em termos de capacidade e segurança de interseções semaforizadas dotadas de grupos focais convencionais, com as dotadas de grupos focais com informação do tempo de verde/vermelho restante na via principal. Foram analisados três modelos distintos, em relação à maneira que é disposta a informação do tempo de verde/vermelho restante. Os resultados obtidos mostram que praticamente não há alteração no valor da capacidade da passagem de veículos pela interseção semaforizada quando se substitui o grupo focal convencional por grupo focal com informador de tempo. Quanto à segurança, a substituição de grupo focal convencional por grupo focal com informador de tempo na via principal trouxe significativa redução do número de acidentes. No entanto, a questão que se coloca é se o ganho de segurança e estética, dos grupos focais com indicação de tempo, não poderia ser obtido com custos menores com o emprego de focos maiores dotados de LED, com anteparos grandes dotados de orla refletiva e com grupos focais posicionados sobre a via (quando for o caso). / The objective of this research was to compare performance - in terms of capacity and safety of - signalized intersections equipped with conventional focus groups, endowed with the focus groups with remaining green/red time information on the main road. Three different models were analyzes, in the manner in which information on remaining green/red time is displayed. The results show that there is practically no change in the value of the capacity of vehicles crossing the signalized intersection when replacing the conventional focus group for a focus group with time informer. Regarding the safety, the replacement of conventional focus group for focus group with time informer on the main road has brought significant reduction in accidents. However, the question that arises is whether the gain in traffic safety, as well as aesthetics, of the focus groups with indication of time could not be obtained at much lower cost with the use of larger foci (when appropriate), with foci endowed with LED, with large screens equipped with reflective edge and with focus groups positioned on the road (when appropriate).

Dois surtos de intoxicação por selênio em suínos que ocorreram no estado do Paraná são descritos. Foram acometidos leitões em fase de creche, 16 de um lote de 100 com 27 dias de idade (surto 1) e 350 de 2285 com 22 dias de idade (surto2) apresentaram poliomielomalácia simétrica focal. Animais que sobreviveram aos surtos desenvolveram lesões de casco características de intoxicação crônica por selênio. Os sinais clínicos iniciaram após 6 dias e 30 horas da introdução da ração com alto teor de selênio nos surtos 1 e 2, respectivamente. O surgimento dos sinais foi abrupto, os animais começavam com andar cambaleante, evoluiam para paralisia dos membros pélvicos e progrediam para paralisia dos membros torácicos e tetraparesia. Os animais do surto 1 não tinham alterações de comportamento e mantinham estado de alerta e animais do surto 2 apresentaram quadros de depressão. Macroscopicamente, observaram-se focos circulares amarelados com áreas deprimidas mais escura, em alguns animais, restritas ao corno ventral da substância cinzenta (H medular) em intumescências cervical e lombar. Microscopicamente, essas áreas corresponderam à malácia da substância cinzenta, caracterizada por microcavitações, perda neuronal, cromatólise, neuronofagia, infiltrado de células Gitter, microgliose, astrócitos de Alzheimer tipo II e proliferação de células endoteliais evidenciadas na imuno-histoquímica (IHQ) para fator de von Willebrand. 9Continua) No segundo surto, dois animais apresentaram vacuolização difusa do citoplasma de neurônios. Em um animal, Astrócitos gemistocíticos foram observados. Na IHQ para Proteína Ácida Glial Fibrilar (GFAP), obteve-se marcação positiva na maioria dos animais e, na IHQ para Proteína S-100, obteve-se marcação em alguns casos. Além dessas alterações medulares, foram encontrados, em dois animais lesões de polioencefalomalácia em porções do tronco encefálico. Fragmentos de fígado de oito animais e ração de ambos os surtos foram encaminhados para dosagem de selênio. Em amostras de ração, detectou-se 3,38 ppm (surto 1) e 154 ppm (surto 2) e em amostras de fígado teve dosagens superiores a 3,34 ppm. No surto 2, foi realizada uma visita onde seis suínos foram eutanasiados para monitoramento de níveis hepáticos de selênio, sendo dois animais controles e quatro sobreviventes do surto. Quarenta e dois dias após a retirada da ração, os níveis de selênio foram inferiores ao controle e ao nível considerado em quadros de intoxicação (3 ppm). / Two outbreaks of selenium poisoning occurred in pigs in Cruzeiro do Iguaçu and Dois Vizinhos, both of the located in Paraná State. The affected pigs were in the post-weaning period, 16 out of 100 were 27 days of age (outbreak 1) and 350 out of 2285 were 22 days of age (outbreak 2). Affected animals showed signs of focal symmetrical poliomyelomalacia. Surviving pigs developed lesions in hoof, which are characteristic of chronic poisoning by selenium. Clinical signs were observed 6 days and 30 hours after the introduction of the feed with high selenium content in outbreaks 1 and 2, respectively. The appearance of the signs was abrupt, beginning with gait and progressing to paralysis of rear limbs and the forelimbs, or tetraparesis. Animals of outbreak 1 were alert and had no behaviors changes and animals of outbreak 2 showed depression. Macroscopically, in some animals there were yellow circular focus with dark areas, restricted to the ventral horn of the gray matter of spinal cord in cervical and lumbar intumescence. Microscopically, these areas corresponded to gray substance malacia characterized by microcavitation, neuronal loss, chromatolysis, Gitter cell infiltrate, neuronophagia, microgliosis, Alzheimer type II astrocytes and proliferation of endothelial cells, which were labeled by immunohistochemistry (IHC) for von Willebrand factor. In the second outbreak, two animals showed a diffuse cytoplasm vacuolization of the neurons. Gemistocytic astrocytes were observed in one animal. In most affected pigs, positive in test for glial fibrillary acid protein (GFAP) was observed, but only in some cases, there was positive anti-S-100 IHC. In addition these spinal cord changes were seen polioencephalomalacia in portions of the brainstem in two animals. Liver samples from eight animals and feed samples from both outbreaks were referred to determine selenium concentration. Selenium dosages in feed samples were 3.38 ppm (outbreak 1) and 154 ppm (outbreak 2) and in liver samples were above 3.34 ppm. Additions six animals were euthanized for monitoring hepatic levels of selenium, two were control animals and four were survivors of the second outbreak. 42 days after the withdrawal of the diet, selenium levels were lower than in internal control and the level seen in intoxication outbreaks (3 ppm).

Introdução: A epilepsia é uma das condições mais comuns na prática neurológica. Sua prevalência na população em geral é expressiva (cerca de 2%). Dentre esses pacientes, existem aqueles que são fármaco-resistentes, ou seja aqueles que não atingem controle de suas crises com dois fármacos adequados de maneira otimizada, os quais correspondem a cerca de 20-40%. Esses pacientes apresentam um controle inadequado de sua condição crônica e o tratamento a longo prazo torna-se insatisfatório e de alto custo, sem levar em consideração a redução da qualidade de vida do paciente, o impacto psicossocial, as incapacidades e o risco aumentado de morte. Somando-se a isso, existe o fato de eles, muitas vezes, necessitarem de cuidadores, geralmente familiares, os quais, por consequência, também deixam de produzir. Sendo assim, é imperativo que tratamentos alternativos custo-efetivos sejam disponibilizados para esses pacientes. A cirurgia da epilepsia é uma opção muito adequada para pacientes selecionados, uma vez que ela pode melhorar substancialmente a qualidade de vida dos pacientes, em muitos casos fazendo até mesmo com que o paciente fique livre de crises, além da redução dos custos à longo prazo. O grande problema é anterior à cirurgia: reside no fato de existir uma certa dificuldade em identificar e encaminhar esses pacientes para uma avaliação adequada, seja por desconhecimento por parte dos médicos em geral, seja pela escassez de recomendações formais. Objetivos: Avaliar uma ferramenta online para indicar pacientes candidatos à cirurgia da epilepsia, colaborando, assim com uma maior facilidade para fins de tomada de decisão clínica com uma melhor identificação destes pacientes. Métodos: Realizamos um estudo transversal avaliando a indicação cirúrgica de pacientes com epilepsia focal, conforme testagem de uma ferramenta online disponível para este fim. Este trabalho foi realizado com pacientes consecutivos que frequentaram o Ambulatório de Epilepsia do Serviço de Neurologia do Hospital de Clínicas de Porto Alegre, no período de janeiro a abril de 2014. Todos os pacientes incluídos no estudo apresentavam o diagnóstico de epilepsia e suas informações foram retiradas da revisão de seus prontuários através de um questionário padronizado respondido pelos pesquisadores. As informações que porventura não constavam registradas em prontuário foram coletadas durante a consulta de rotina. No total, foram avaliados 211 pacientes. Resultados: No nosso estudo, primeiramente realizamos uma análise de prevalência, encontrando um resultado de 56,9% de pacientes com indicação à avaliação cirúrgica. Além disso, realizamos uma avaliação das variáveis que contribuem para a indicação ou não do tratamento cirúrgico. Nessa etapa, encontramos a frequência das crises, o número de fármacos testados e a presença de efeitos colaterais como as variáveis com maior significância estatística para indicação ao tratamento cirúrgico. Conclusão: Acreditamos que este trabalho possui grande relevância clínica por se tratar de uma ferramenta que pode ajudar na tomada de decisão para fins de tratamento, beneficiando, assim, pacientes e possivelmente reduzindo custos do sistema de saúde a médio e longo prazo. / Background: Epilepsy is one of the most commons neurological conditions in practice. Its prevalence in the general population is significant (about 2%). Among these patients, there are those that are drug-resistant (those who do not achieve control of their seizures with two suitable drugs optimally), which correspond to about 20-40%. These patients have inadequate control of their chronic condition and long-term treatment becomes unsatisfactory and expensive, regardless of the reduced quality of life of patients, the psychosocial impact, disability and increased risk of death. In addition, the fact that they often need caregivers usually familiar, which, therefore, also fail to produce. It is therefore imperative that cost-effective alternative treatments are available for these patients. The epilepsy surgery is a suitable option for selected patients, since it can substantially improve the quality of life of patients, in many cases making even the patient seizure free, in addition to reducing costs in the long term. The big problem is before surgery: lies in the fact that there is some difficulty in identifying and referring these patients for proper evaluation, either by ignorance on the part of physicians in general, and the lack of formal recommendations. Objectives: Evaluate an online tool to nominate patients candidates for epilepsy surgery, thus contributing to a larger facility for the purposes of clinical decision-making with better identification of these patients. Methods: We conducted a cross-sectional study evaluating the surgical indication in patients with focal epilepsy, as testing of an online tool available for this purpose. This work was performed with consecutive outpatients attending at the Epilepsy Clinic of the Hospital de Clínicas de Porto Alegre, in the period of January-April 2014. All patients included in the study had a diagnosis of epilepsy and their information was taken from the review of their medical records using a standardized questionnaire answered by researchers. The informations who were not registered, were collected during a routine visit. In total, 211 patients were evaluated. Results: In our study, first we conducted a prevalence analysis, finding a result of 56.9% of patients referred for surgical evaluation. In addition, we conducted an evaluation of variables that contribute to the indication or not of surgical treatment. At this stage, we found the frequency of seizures, the number of tested drugs and the presence of side effects such as variables with greater statistical significance for indication for surgical treatment. Conclusion: We believe that this work has great clinical relevance because it is a tool that can help in decision making for treatment, thus benefiting patients and reducing health care costs in the medium and long term.

L’implication d’un facteur circulant et des dysfonctions du système immunitaire entrainant les altérations de la barrière de filtration glomérulaire a été suggérée dans la pathogénèse de la hyalinose segmentaire et focal récidivante. Nous avons identifié par spectrométrie de masse la présence de la protéine CASK dans des sérums de patients après immunoadsoroption sur une colonne de protéine A. CASK recombinante est capable d'induire des modifications de l’architecture des podocytes in vitro, tels qu’une redistribution de la protéine de diaphragme de fente ZO-1 et de la protéine régulatrice d’actine synaptopodine, et une perte de fibres de stress d’actine. Ces podocytes acquièrent ainsi un phénotype motile et une perméabilité accrue à l’albumine en présence de CASK recombinante in vitro. L’injection de CASK chez des souris entraine une protéinurie et l’effacement des pédicelles de podocytes. L’interaction entre CASK et son récepteur CD98 dans les podocytes a été mise en évidence par l’expérience de pontage covalent et co-immunoprécipitation. L’inhibition de l’expression de CD98 par ARNi a permis de préserver l’architecture des podocytes en présence de CASK. Nous avons remarqué la surexpression de CASK dans les monocytes chez les patients atteints de la HSF récidivante par rapport aux témoins. In vitro, CASK est surexprimée dans les macrophages ayant une polarité M2 et est retrouvée dans le surnageant de la culture de ces cellules. La sécrétion de CASK est associée aux exosomes qui sont des microvésicules d’origine endosomale. Dans les cellules, CASK est partiellement co-distribuée avec ALIX, un marqueur exosomal, et leur interaction a été mise en évidence par co-immunoprécipitation. CASK est fortement exprimée dans les exosomes de patients atteints de HSF récidivante comparé aux donneurs sains. Le traitement des podocytes par des exosomes issus des macrophages de type M2 induit des altérations du cytosquelette et augmente la motilité des podocytes comme cela avait été observé en présence de CASK recombinante. Pour conclure, nous avons identifié CASK comme nouveau facteur soluble qui pourrait jouer un rôle au cours de la HSF récidivante après transplantation rénale. Ces découvertes ouvrent de nouvelles orientations pour le traitement des malades atteints de SNI récidivant. / Focal segmental glomerulosclerosis (FSGS) is often associated with a high rate of progression to end-stage renal disease. The idiopathic form has a high recurrence rate (rFSGS) after transplantation suggesting the presence of a systemic circulating factor that causes the glomerular permeability. This factor can be removed by plasmapheresis or immunoadsorption using protein-A columns. We used mass spectrometry to analyze the proteins eluted from protein-A columns, taken from patients with rFSGS after immunoadsorption. A serum form of calcium/calmodulin-dependent serine/threonine kinase (CASK) was identified in rFSGS patients but not in controls. In cultured podocytes, recombinant CASK induced reorganization of the actin cytoskeleton. We also demonstrated the interaction of CASK with CD98 at the cell surface. Injection of recombinant CASK in mice induced proteinuria and foot process effacement on podocytes. We identified that CASK is produced by monocytes in patients with rFSGS. CASK is also expressed and secreted by M2 polarized macrophages but not by M1 subset. CASK was associated with exosomes produced by these cells. CASK has a partial codistribution with ALIX, an exosomal component involved in their development. We’ve also demonstrated that CASK interacts with ALIX in M2 macrophages. Moreover exosomes derived from M2 macrophages cause podocytes cytoskeleton alterations and increase of podocyte motility as observed previously with recombinant CASK. In conclusion, a serum form of CASK secreted by macrophages acts as a permeability factor in patients with rFSGS suggesting its involvement in the physiopathology of rFSGS.

<div>Mesenchymal stem cells (MSCs) are responsive to mechanical stimuli that play an essential role in directing their differentiation to the chondrogenic lineage. A better</div><div>understanding of the mechanisms that allow MSCs to respond to mechanical stimuli is important to improving cartilage tissue engineering and regenerative medicine. Hydrostatic pressure (HP) in particular is known to be a primary mechanical force in joints. However, little is known about the underlying mechanisms that facilitate HP</div><div>mechanotransduction. Understanding the signaling pathways in MSCs in transducing HP to a beneficial biologic response and their interrelationship were the focus of this thesis. Studies used porcine marrow-derived MSCs seeded in agarose gel. Calcium ion Ca++ signaling, focal adhesion kinase (FAK) involvement, and sirtuin1 activity were investigated in conjunction with HP application.</div><div><br></div><div><div>Intracellular Ca++ concentration was previously shown to be changed with HP application. In our study a bioreactor was used to apply a single application of HP to the MSC-seeded gel structures and observe Ca++ signaling via live imaging of a fluorescent calcium indicator in cells. However, no fluctuations in Ca++ concentrations were observed with 10 minutes loading of HP. Additionally a problem with the biore actor design was discovered. First the gel was floating around in the bioreactor even without loading. After stabilizing the gel and stopping it from floating, there were still about 16 µm of movement and deformation in the system. The movement and deformation was analyzed for the gel structure and different parts of the bioreactor. </div><div><br></div><div>Furthermore, we investigated the role of FAK in early and late chondrogenesis and also its involvement in HP mechanotransduction. A FAK inhibitor was used on MSCs from day 1 to 21 and showed a dose-dependent suppression of chondrogenesis. However, when low doses of FAK inhibitor added to the MSC culture from day 21 to 42, chondrogenesis was not inhibited. With 4 hour cyclic HP, FAK phosphorylation increased. The beneficial effect of HP was suppressed with overnight addition of the</div></div><div><div>FAK inhibitor to MSC medium, suggesting FAK involvement in HP mechanotransducation by MSCs.</div></div><div><br></div><div>Moreover, sirtuin1 participation in MSC chondrogenesis and mechanotransduction was also explored. The results indicated that overnight sirtuin1 inhibition increased chondrogenic gene expression (Agc, Col2, and Sox9) in MSCs. Additionally, the activity of sirtuin1 was decreased with both 4 hour cyclic hydrostatic pressure and inhibitor application. These two together demonstrated that sirtuin1 inhibition enhances chondrogenesis.</div><div><br></div><div><div>In this research we have investigated the role of Ca++ signaling, FAK involvement, and sirtuin1 activity in the mechanotransduction of HP in MSCs. These understandings about the mechanisms regulating the chondrogenesis with respect to HP could have important implications for cartilage tissue engineering and regenerative studies.</div></div>

Förster Resonance Energy Transfer (FRET)-based techniques are gaining an increasing importance in cell biology and cell-matrix adhesion studies because they allow both the detection of conformational changes of target proteins and their localisation in cells. Frequency Domain-Fluorescence Lifetime Microscopy (FD-FLIM) is currently considered one of the most reliable methods to measure FRET in live cells. However, due to its dependence on many technical prerequisites, its use is not yet widespread. The purpose of this work was to first establish FD-FLIM measurements of FRET on a new FD-FLIM microscope module. Then we aimed to apply FD-FLIM-FRET measurements to the study of conformational changes of the cell matrix-adhesion proteins vinculin and integrin and of the growth factor receptor Tie-2. In the first part of the work, published FRET probes including distance-sensors and two sets of vinculin-based probes were extensively tested with FD-FLIM, sensitised emission and ratiometric FRET. FD-FLIM was shown to be the most accurate method in approximating molecular distances between fluorophores. Moreover this study unveiled specific caveats associated with both existing vinculin FRET probes. FD-FLIM was then used to study conformational changes of the extracellular matrix receptor alphavβ3 integrin and of the angiopoietin receptor Tie-2 using specific FRET probes designed by us. While data showed that the alphav-integrin-FRET probe localised to adhesion sites, more experiments will be required to evaluate its full functionality. The Tie-2-FRET probe was fully functional and, upon ligand binding, allowed the detection of a bending movement of the extracellular domain towards the cell membrane. Finally, a combination of FRET, immunofluorescence and tension release experiments were used to show that intracellular tension is not required to maintain integrins in their activated conformation. However, intracellular tension is required to recruit other key proteins such as vinculin, talin and tensin to adhesions sites. Overall this work demonstrates the importance of FD-FLIM-FRET as a tool to investigate conformational changes of adhesion proteins and transmembrane receptors within the cell environment.

Diferenciar-se no competitivo mercado global exige que as empresas sejam cada vez mais inovadoras. Considerando que as inovações são desenvolvidas por pessoas interagindo em certo espaço, buscou-se por pesquisas sobre esses ambientes de inovação. Como os trabalhos detectados apenas diagnosticavam os ambientes e não faziam proposições de como aperfeiçoá-los, o presente estudo visa preencher essa lacuna, propondo uma sistemática para aprimorar os ambientes de inovação. Como forma de atingir esse objetivo, foram identificadas, por meio da busca teórica, nove dimensões que contemplam esses complexos ambientes. Para cada dimensão foi criada uma série de perguntas, culminando em um questionário com 40 indagações. Ele foi respondido quali-quantitativamente por 30 desenvolvedores de inovações de cinco grandes empresas. De posse do conjunto de dados daí oriundos, foram realizadas análises estatísticas como suporte para as demais análises. Para uma das análises foi adotada a técnica de Grupo Focal (GF), o qual foi composto por pessoas da alta gestão das empresas pesquisadas e por professores estrangeiros. Visando auxiliar a condução do GF, foi desenvolvido um jogo especificamente para esse fim. Como forma de verificar se ao menos duas dimensões apresentavam resultados significativamente diferentes para a soma de rankings foi utilizado o teste de Kruskall Wallis. O resultado do teste evidenciou que as dimensões Liderança e Autonomia apresentaram notas significativamente mais altas que as dimensões Processos e Recursos. Como parte final importante, a sistemática propõe um Guia de Diretrizes, embasado nas ideias expostas pelos autores estudados, pelos respondentes do questionário e pelos participantes do GF. Compreende-se que toda e qualquer empresa pode adequar a sistemática e aprimorar seus ambientes organizacionais direcionados a inovações. / Differentiate themselves in the competitive global market requires companies to be more innovative. Considering that innovations are developed by people interacting in a certain space, it searched for researches about these innovation environments. As the works detected only diagnosed environments and made no proposals for how to improve them, this study aims to fill this gap by proposing a system to improve the innovation environments. In order to achieve this goal, nine dimensions that address these complex environments have been identified through the theoretical search. For each dimension a series of questions was created, culminating in a questionnaire with 40 questions. The questionnaire was answered in a qualitative and quantitative way by 30 innovation developers within five large companies. Based on derived data set, statistical analysis were performed as support for other analysis. In order to perform the analysis it was adopted the Focus Group technique (FG), which was composed of people from the top management of those companies surveyed and foreign teachers. Aiming to assist the conduct of the FG, a game was developed specifically for this purpose. In order to check whether at least two dimensions had significantly different results for the sum of rankings was used the Kruskal-Wallis test. The test result showed that the dimensions Leadership and Autonomy had significantly higher scores than the dimensions Processes and Resources. As an important final part, the method proposes a Guide of Directives, based on the ideas exposed by the studied authors, by the respondents of the questionnaire and the participants of the FG. It is understood that any company can tailor the method and improve organizational environments driven to innovations.

Entre 15 et 20% des cancers du sein diagnostiqués sont des cancers du sein triple-négatifs (CSTN). Ce sous-type de cancer du sein est caractérisé par l'absence ou le faible niveau d'expression du récepteur au facteur de croissance épidermique de type 2 (HER2) et des récepteurs hormonaux à l'œstrogène et à la progestérone. Par définition, les patientes atteintes de CSTN ne peuvent bénéficier des traitements antihormonaux ou des thérapies ciblées anti-HER2 qui ont nettement amélioré la prise en charge thérapeutique des autres sous-types de cancers du sein. En marge de ces progrès, les CSTN sont ainsi principalement traités par chimiothérapies cytotoxiques, des thérapies ne parvenant pas toujours à empêcher leur dissémination métastatique. Par conséquent, les CSTN sont aujourd'hui associés à des pronostics relativement mauvais et l'identification de nouvelles cibles thérapeutiques constitue un enjeu majeur de la recherche sur le cancer du sein. C'est dans ce contexte qu'une cible thérapeutique potentielle contre les CSTN a récemment été identifiée: la sérine-thréonine kinase PKC thêta. Cette PKC nouvelle est fortement exprimée dans les CSTN alors qu'elle ne l'est pas, ou très faiblement, dans des cancers du sein exprimant le récepteur aux œstrogènes et dans les tissus mammaires non transformés. L'objectif de ma thèse a été d'étudier la fonction de PKC thêta dans le contrôle de l'invasion de cellules tumorales mammaires, une étape clé de la formation de métastases. Nos travaux montrent qu'une inhibition de PKC thêta aboutit à une nette diminution des capacités invasives de lignées de cellules CSTN in vitro. De même, in vivo cette inhibition limite fortement la formation de métastases chez la souris. Nous identifions le mécanisme moléculaire par lequel PKC thêta contrôle l'invasion: PKC thêta est capable d'activer la voie des adhérences focales en phosphorylant directement la kinase des adhérences focales (FAK) sur des sites de phosphorylations encore jamais identifiés, les sérines 892 et 893. Ces phosphorylations sont essentielles aux effets positifs de PKC thêta sur l'invasion et la FAK phosphorylée de la sorte est retrouvée spécifiquement au front de cellules CSTN en migration. De façon intéressante, ces phosphorylations de FAK par PKC thêta permettent une modification de la dynamique de formation des adhérences cellule/matrice ainsi que celle des protrusions. Le contrôle de ces protrusions passe très certainement par une altération de la dynamique d'activité des RhoGTPases induite par PKC thêta De surcroît, l'utilisation d'une PKC thêta activable par la rapamycine nous permet de finement étudier la temporalité des effets de PKC thêta sur la génération des protrusions et des adhérences cellule/matrice. Enfin, concernant le contrôle de l'activité de PKC thêta en amont, nous constatons que son activation de même que ses effets sur la voie FAK et l'invasion dépendent entièrement de CDCP1 (Cub Domain-Containing Protein 1), un récepteur transmembranaire associé à l'agressivité de plusieurs cancers, dont les CSTN. Mes travaux mettent ainsi en évidence un mécanisme inédit de contrôle de la voie FAK permettant l'invasion de cellules tumorales mammaires. De plus, ils valident PKC thêta en tant que cible thérapeutique potentielle dont l'inhibition pourrait permettre de limiter la dissémination métastatique des CSTN et ce sans effets secondaires majeurs, la fonction physiologique de PKCthêta étant non essentielle. / Triple-negative breast cancer is a subtype of breast cancer that primarily affects women under the age of 40. TNBCs account for 15 to 20% of all diagnosed breast cancers and are defined by tumour cells lacking or weakly expressing the oestrogen receptor, the progesterone receptor and the human epidermal growth factor receptor 2 (HER2). By definition, these cancers cannot benefit from hormonal therapies or targeted therapies against the HER2 that have both proved to be very efficient in other breast cancer subtypes. Hence, therapies against TNBC are based essentially on classical cytotoxic chemotherapies that are not always able to block metastatic dissemination of those cancers. As a consequence, TNBCs are associated with poor prognosis and thus, finding new therapeutic targets for TNBC constitutes a major challenge for breast cancer research. In that context, a new potential TNBC therepeutical target has recently been identified: the serine threonine PKC theta. This novel PKC is highly expressed in TNBC whereas it is not expressed in breast cancer expressing the oestrogen receptor or non-transformed mammary tissues. The aim of my PhD was to study the function of PKC theta in the control of breast cancer cells invasion, a key step to metastasis formation that can be defined as the ability of cells to migrate through an extracellular matrix. We have shown that PKC theta inhibition leads to strong diminution of the invasive abilities of TNBC cell lines in vitro. Accordingly, we show in vivo that PKC theta inhibition strongly impairs metastasis formation in mice. We have identified the molecular mechanisms through which PKC theta controls invasion: PKC theta is able to activate focal adhesion signalling by directly phosphorylating FAK (Focal Adhesion Kinase) at newly identified phosphorylation sites, serines 892 and 893. We observe that this phosphorylated FAK localizes to nascent adhesions at the leading edge of migrating breast cancer cells and that those phosphorylations are essential to PKC theta control of invasion. PKC theta phosphorylations of FAK also modify the dynamic of cell/matrix adhesions and protrusion formation. The effects on protrusion formation are most certainly linked to PKC theta alteration of Rho GTPases activity dynamic. Furthermore, the use of an activatable PKC theta enables us to precisely study the temporality of PKC theta effects on both protrusions and adhesions. Protrusions and adhesions being essential to cell migration, those results explain PKC theta positive effects on invasion. Finally, regarding the upstream control of PKC theta we observe that PKC theta activation, together with its effect on FAK and invasion, depend on CDCP1, a transmembrane receptor that has been linked to the aggressiveness of several cancers, including TNBC. Altogether, my work reveals a new mechanism of FAK pathway activation leading to breast cancer cell invasion. Moreover, it further defines PKC theta as an interesting therepeutical target, whose inhibition could limit metastatic dissemination of TNBC without major secondary effects, as PKC theta has a non-essential physiological function.

O objetivo desta pesquisa foi comparar o desempenho - em termos de capacidade e segurança de interseções semaforizadas dotadas de grupos focais convencionais, com as dotadas de grupos focais com informação do tempo de verde/vermelho restante na via principal. Foram analisados três modelos distintos, em relação à maneira que é disposta a informação do tempo de verde/vermelho restante. Os resultados obtidos mostram que praticamente não há alteração no valor da capacidade da passagem de veículos pela interseção semaforizada quando se substitui o grupo focal convencional por grupo focal com informador de tempo. Quanto à segurança, a substituição de grupo focal convencional por grupo focal com informador de tempo na via principal trouxe significativa redução do número de acidentes. No entanto, a questão que se coloca é se o ganho de segurança e estética, dos grupos focais com indicação de tempo, não poderia ser obtido com custos menores com o emprego de focos maiores dotados de LED, com anteparos grandes dotados de orla refletiva e com grupos focais posicionados sobre a via (quando for o caso). / The objective of this research was to compare performance - in terms of capacity and safety of - signalized intersections equipped with conventional focus groups, endowed with the focus groups with remaining green/red time information on the main road. Three different models were analyzes, in the manner in which information on remaining green/red time is displayed. The results show that there is practically no change in the value of the capacity of vehicles crossing the signalized intersection when replacing the conventional focus group for a focus group with time informer. Regarding the safety, the replacement of conventional focus group for focus group with time informer on the main road has brought significant reduction in accidents. However, the question that arises is whether the gain in traffic safety, as well as aesthetics, of the focus groups with indication of time could not be obtained at much lower cost with the use of larger foci (when appropriate), with foci endowed with LED, with large screens equipped with reflective edge and with focus groups positioned on the road (when appropriate).

O presente projeto de pesquisa trata da investigação detalhada dos aspectos relacionados à \'\'Região Ótima\" do campo de radiação, particularmente voltada a sistemas mamográficos. Tal região foi definida em pesquisas anteriores como a faixa do campo onde o sistema apresenta sua melhor performance em termos de resolução espacial, produzindo, portanto, imagens mais nítidas. A investigação aqui proposta tomará por base a associação de dois métodos de avaliação de sistemas de imagem radiológica, que empregam simulação computacional para determinar as Funções de Transferência de Modulação (FTMs) - método de simulação a partir da FEL [SCHIABEL92] e método de simulação a partir da FEP [MARQUES92] - devidas ao ponto focal em diversas orientações e posições do campo. A finalidade é propor um método de prever a existência e extensão da Região Ótima, bem como seu significado prático para a nitidez da imagem e para a utilização de equipamentos mamográficos não isotrópicos, através de comparações entre os modelos de simulação. A comprovação prática dos resultados e das conclusões foi complementada com avaliações de imagens radiográficas feitas com \"phantoms\". / The propose of this work is to make a detailed investigation related with the optimum region aspects of x-rays radiation fields, specially in mammographic systems. Previous researches defined the optimum region as a field range where the system produces the best performance and best sharpened images.This investigation is based on the association of two analysis methods of radiological imaging systems which use computational simulation to determine the focal spot Modulation Transfer Function (MTF) - simulation method of Spread Line Function [SCHIABEL92] and simulation method of Spread Point Function [MARQUES94] - in severa! orientations and x-ray field positions. The intent is to propose a method to preview the existence of the optimum region, as well its practical meaning for the image sharpness and the utilization of a non-isotropic mammographic equipment, through comparison between both simulation models. The practical validation of the results and conclusions was complemented with the valuation of some radiographic images made with \"phantoms\".