AMP-activated protein kinase (AMPK) is a key regulator of energy homeostasis in cells. It has been implicated as a therapeutic target for various metabolic diseases like type II diabetes and obesity. However, its role in cancer is context-dependent and therefore warrants further studies to explore its possible use as a therapeutic target. AMPK can either promote or retard the growth of cancer cells depending on other cues and stresses in the milieu of the cancer cells. This study aims to understand AMPK signalling in response to extracellular cues of matrix deprivation and matrix stiffness that are important determinants of metastasis. 1) Calcium-Oxidant Signalling Network Regulates AMPK Activation upon Matrix Deprivation. Recent work from our lab, as well as others, has identified a novel role for the cellular energy sensor AMP-activated protein kinase in epithelial cancer cell survival under matrix deprivation. However, the molecular mechanisms that activate AMPK upon matrix-detachment remain unexplored. In this study, we show that AMPK activation is a rapid and sustained phenomenon upon matrix deprivation, while re-attachment to the matrix leads to its dephosphorylating and inactivation. Since matrix-detachment leads to loss of integrin signalling, we investigate whether integrin signalling negatively regulates AMPK activation. However, modulation of FAK or Src, the major downstream components of integrin signalling, fails to cause a corresponding change in AMPK signalling. Further investigations reveal that the upstream AMPK kinases, LKB1 and CaMKKβ, contribute to AMPK activation upon detachment. Additionally, we show LKB1 phosphorylation and cytosolic translocation upon matrix deprivation, which might also contribute to AMPK activation. In LKB1-deficient cells, we find AMPK activation to be predominantly dependent on Caskβ. We observe no change in ATP levels under detached conditions at early time points suggesting that rapid AMPK activation upon detachment is not triggered by energy stress. We demonstrate that matrix deprivation leads to a spike in intracellular calcium as well as oxidant signalling and both these intracellular messengers contribute to rapid AMPK activation upon detachment. We further show that ER calcium release induced store-operated calcium entry (SOCE) contributes to intracellular calcium increase, leading to ROS production, and AMPK activation. We additionally show that the LKB1/CaMKK-AMPK axis and intracellular calcium levels play a critical role in anchorage-independent cancer sphere formation. We find a significant increase in LKB1 as well as pACC levels in breast tumour tissues in comparison to normal tissues. Further, we observe a significant correlation between LKB1 and pACC levels in breast tumour tissues suggesting that LKB1-AMPK signaling pathway is active in vivo in breast cancers. Thus, the Ca2+/ROS triggered LKB1/CaMKK-AMPK signalling cascade may provide a quick, adaptable switch to promote survival of metastasising cancer cells. 2) Extracellular Matrix Stiffness Regulates Stemless through AMPK. Cancer cells experience changes in extracellular matrix stiffness during cancer progression. However, the signalling pathways utilised in sensing matrix stiffness are poorly understood. In this study, we identify AMPK pathway as a possible mechanosensory pathway in response to matrix stiffness. AMPK activity, as measured by downstream target phosphorylation, is found to be higher in soft matrix conditions. We additionally show that compared to stiff matrices, soft matrices increase stemless properties, as evidenced by the increased expression of stemless markers, which is dependent on AMPK activity. Thus, we elucidate a novel mechanotransduction pathway triggered by matrix stiffness that contributes to stemness of cancer cells by regulating AMPK activity. Taken together, our study identifies a novel calcium-oxidant signaling network in the rapid modulation of AMPK signaling in the context of matrix detachment. This pathway is especially relevant in the context of metastasising cancer cells that may not face energy stress in the blood stream but are matrix-deprived. Inhibition of AMPK might compromise the viability of these circulating cells thereby reducing the metastatic spread of cancer. Our study further suggests that varying stiffnesses experienced by cancer cells can modulate AMPK activity and this, in turn, regulates stem-like properties. Thus our study provides novel insights into various extracellular cues that regulate this kinase and contribute to cell survival and metastasis. This knowledge can be utilised in the stage-specific use of AMPK inhibitors in the treatment of breast cancer patients.

In Canada alone, there were an estimated 800,000 visually impaired people in 2007, costing the federal government an annual amount of $15.8 billion in services, treatments and lost revenue. These costs are estimated to double by the year 2032, as the population ages. The leading causes of visual impairment and blindness is retinal degeneration, characterized by the progressive death of retinal cells. The research presented in this PhD thesis aimed to prevent retinal degeneration by over-expressing the X-linked Inhibitor of Apoptosis (XIAP) in retinal cells using plasmid and adeno-associated viral vectors. The work is divided into four sequential chapters targeted at developing an anti-apoptotic gene therapy strategy to prevent retinal cell death. The first chapter examines XIAP gene therapy in the treatment of Leber’s Hereditary Optic Neuropathy (LHON). In vitro studies using the 661W cone-photoreceptor cell line showed that XIAP over-expression significantly lowers cell death when 661W cells are exposed to a number of apoptotic stimuli. In a mouse model of Leber’s Hereditary Optic Neuropathy (LHON), XIAP expression in retinal ganglion cells (RGCs) protected the ultrastructure of the RGC axons within the optic nerve, in addition to providing evidence of functional protection. The second and third chapters further examine the potential for XIAP gene therapy in the treatment of retinal disease by developing an in vivo model of retinal detachment in cats, followed by evaluating the efficacy of XIAP gene therapy intervention. When XIAP was over-expressed in the photoreceptor cells, there was significant structural protection and trends in preservation of function in this model of degeneration. Finally, the fourth chapter explores an alternate method to viral gene therapy by evaluating the efficacy and toxicity of chitosan microparticles as a protein delivery system to the retina. Results show that chitosan microparticles are mucosal-adhesive and are non-toxic at low concentrations in vitro in 661W cells and in vivo in rats. This thesis work provides strong evidence that XIAP gene therapy is an effective method for preventing retinal degeneration, and works as a broad spectrum gene therapy strategy that can be applied to different forms of retinal degeneration.

L’œuvre littéraire de Boris Vian interpelle par la diversité des émotions qu’elle suscite. Elle est pourtant restée longtemps méconnue, masquée par les talents protéiformes de son auteur. Boris Vian, dont la majorité des textes ont été publiés à titre posthume, fut perçu comme un touche-à-tout avant d’être véritablement reconnu comme écrivain, pour finalement entrer dans l’édition de la Pléiade en 2010, cinquante et un an après sa mort. Le premier réflexe est de faire appel à la notion de fantaisie pour analyser son œuvre. Le monde fictionnel qu’il crée est un univers fantaisiste où triomphent imaginaire et inventivité. Pourtant, des univers contradictoires s’entremêlent : féerie et cruauté, légèreté et inquiétude, désinvolture et gravité, imaginaire et réalité. En nous appuyant uniquement sur les textes de fiction en prose (romans, nouvelles et pièces de théâtre), nous nous sommes donc interrogés sur la légitimité de la notion de fantaisie. Son évidence apparente résiste-t-elle à un examen plus poussé ? Ce questionnement nous a conduits à élaborer la notion de « fantaisie noire ». Tantôt féerique, invraisemblable, langagière, comique ou parodique, la fantaisie se heurte à l’intériorité des personnages et à un sentiment d’inquiétude qui contamine les êtres et les choses. La fantaisie cède le pas à la noirceur d’un monde étouffant où le fantasme se révèle dans toute sa puissance. Le retour à la fantaisie n’est alors possible que par des effets de distanciation comiques et une inventivité langagière qui contribue à laisser l’œuvre ouverte. / Boris Vian's literary work calls to mind by the feelings it arouses. For a long time it nevertheless remained unknown concealed by its author's protean talents. Boris Vian, whose texts were mostly published posthumously, wasn't at the beginning seen as a writer to finally get in the Pléiade in 2010, 51 years after his death. To analyse his work it appears natural to consider the idea of fantasy. The fictional world he created remains a fantasist one where imagination and inventiveness prevail. Yet, opposing worlds get mixed up: fairy and cruelty, casualness and anxiety, indifference and seriousness, fantasy and reality. Considering only the fictional texts in prose (novels, short stories and plays) we questionned the legitimity of the fantasy notion. Does its obviousness withstand a further analysis? This questioning drove us to the idea of 'fantaisie noire'. Sometimes magical, incredible, linguistic, comical or parodic, the fantasy collides with the inwardness of the characters and with an anxiety that contaminates both beings and objects. The fantasy defers to an oppresive world where the dream reveals itself in all its power. The come back to fantasy is then only possible by comical detachments and a linguistic inventiveness that contributes to let the work opened.

Deafblindness is a combined impairment of vision and hearing with an incidence of about 1: 8000 children and 1: 5500 adults. The most common genetic causes are the Stickler (STL) and Usher (USH) syndromes. The main goal of this work is to provide an up-to-date overview of STL and USH in the Czech and Slovak Republic (CR and SR), to determine the correlations between the genotype and phenotype in our population and the associated diagnostic criteria. Using sequencing and MLPA we examined 45 patients from 28 families for suspected STL. We found potentially causal variants of STL genes in 39 patients from 22 families. Fifteen different COL2A1 variants (8 being novel) were found in 28 patients from 18 families and 4 novel COL11A1 variants were found in 11 patients from 4 families. We identified the cause of the disease in 79 % of the families. The USH study involved 30 patients from 27 families. The most frequent cause was USH2A pathogenic variants, i.e. 19 variants in 14 families, 9 being novel. Less common were pathogenic variants in MYO7A (6 variants in 3 families, 5 being novel), USH1C and CDH23 (3 variants, 2 being novel, in 2 families both) genes. In 2 families, compound heterozygosity was found for variants in two different USH genes. The deafblindness etiology was clarified for 24 patients from...

The paper introduces briefly topics of retinal detachment, vitrectomy and applicable postoperative care. A system for increasing patient comfort is described, which continuously records and signalizes head tilt. The software part of aforementioned system is implemented, using C++ Builder programming environment and helper libraries supplied by system's hardware component vendors. This software application allows user to analyze recorded data and manage the system. Application's user interface and usage is described in detail, as well as implementation details concerning internal functions and organization.

Depuis le début des années 2000 se développe une littérature enjoignant les professionnels au contact des malades d'Alzheimer à "personnaliser" leur prise en charge. Derrière ce terme se cache en réalité une véritable injonction à l'humanisation dans le cadre d'une relation où cette dimension semble faire défaut. Ce qui est demandé au personnel médical et paramédical, c'est un engagement véritable et authentique auprès de cette population. Ce qui est visé, c'est un contrôle des émotions et de leur manifestation.Cette thèse interroge la mise en pratique de la "personnalisation" au sein des unités Alzheimer en EHPAD. S'appuyant sur une démarche qui s'inspire des enquêtes interactionnistes, cette recherche montre non seulement la banalité de l'"engagement" dans ce type d'univers, mais également la complexité de sa mise en oeuvre.Dans la perspective des études sur le care, un travail souterrain, qui reste le souvent invisible, consiste à faire en sorte que la vie de l'étage soit possible pour l'ensemble des individus en présence. C'est cette intelligence de la situation qui conduit, d'un côté, à éloigner le risque de la réification et, de l'autre, à prévenir l'épuisement professionnel.Bien loin de la rhétorique de la "bonne distance professionnelle", l'enquête montre que l'activité des soignants s'articule autour d'un subtil dosage entre engagement et distanciation, pour reprendre la proposition d'Elias (1956). Les émotions sont tout à la fois une nécessité dans le cadre de la réalisation des tâches qui incombent aux professionnels, et une source de danger qu'il faut parfois savoir mettre à distance.L'univers des unités Alzheimer est marqué par un poids relativement important de la régulation autonome par rapport à la régulation de contrôle, pour reprendre la terminologie de Reynaud (2004). Les velléités de formalisation achoppent face au caractère fondamentalement insaisissable et local du care. / In France, since early 2000s spreads a literature inviting professionals in contact with people suffering from Alzheimer disease to "personalize" the way they take care of them. This term refers to a humanization that seems to fade away in this particular context. What is asked to medical and paramedical staff, is a true and authentic commitment toward these patients. What is aimed, is a control of emotions and the way they are expressed.This Ph.D explores the way in which "personalization" is practically accomplished in the context of Alzheimer’s Special Care Units. Based on interviews and observations, it shows the banality of "commitment", and also the complexity of it’s execution. From the ethics of care perspective, an invisible work makes life possible for every protagonist living in that kind of environment. This cleverness of the situation drives away the danger of reification, and prevents burnout.Far from the chimerical "professional distance", this field work shows an articulation between commitment and detachment (Elias, 1956). Emotions appears to be a necessity in order to carry out the tasks, but also a danger that requires to be put away. Thus, Alzheimer’s units are characterized by the relative importance of autonomous regulation, in comparison with control regulation (Reynaud, 2004) : formalization process struggle due to the elusive and local nature of the ethics of care.

Models using 3D cell culture techniques are increasingly accepted as the most biofidelic in vitro representations of tissues for research. These models are generated using biomatrices and bulk populations of cells derived from tissues or cell lines. This thesis study focuses on an alternate method to culture individually selected cells in relative isolation from the rest of the population under physiologically relevant matrix conditions. Matrix gel islands are spotted on a cell culture dish to act as support for receiving and culturing individual single cells; a glass capillary-based microfluidic setup is used to extract each desired single cell from a population and seed it on top of an island. Using examples of breast and colorectal cancers, we show that individual cells evolve into tumors or aspects of tumors displaying different characteristics of the initial cancer type and aggressiveness. By implementing a morphometry assay with luminal A breast cancer, we demonstrate the potential of the proposed approach to studying phenotypic heterogeneity. Results reveal that intertumor heterogeneity increases with time in culture and that varying degrees of intratumor heterogeneity may originate from individually seeded cells. Moreover, we observe a positive correlation between fast-growing tumors and the size and heterogeneity of their nuclei.

Different theoretical approaches and interpretations offer diverse delineations and clusters of Enneagram type in terms of Horney’s interpersonal trends of moving toward, moving against and moving away from people. The present study reports the results of an empirical investigation into the relationship between Enneagram type and Horney’s interpersonal trends. A sample of 2 3 participants completed the Test of Object Relations (TOR) and 125 of these participants completed the Horney-Coolidge Tridimensional Inventory (HCTI). Two one-way, between-groups multivariate analyses of variance revealed differences between Enneagram types for each of the HCTI interpersonal trends of compliance, aggression and detachment and the TOR dimensions of separation anxiety, symbiotic merging, narcissism, egocentricity, social isolation and fear of engulfment. For each trend, an Enneagram type could be identified as a unique marker or benchmark of the trend. However, the empirical result does not offer clear support for one theoretical approach or viewpoint rather than another. / Psychology / M.A. (Psychology)

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Le présent mémoire constitue une tentative de circonscrire - par l’étude d’un corpus textuel principalement emprunté à l’œuvre vernaculaire (allemande) de Maître Eckhart de Hochheim (1260-1328) – le rôle joué par certains motifs conceptuels caractérisant la notion moderne de sujet-agent au sein de la pensée de ce philosophe, théologien et prédicateur. Plus précisément, il y est question de déterminer en quoi le « je » (ich) décrit en plusieurs lieux textuels de l’œuvre d’Eckhart présente les caractères d’autonomie et de transparence à soi qui sont l’apanage de la subjectivité telle que la conçoit majoritairement une certaine modernité postcartésienne. Notre argument, qui se déploie sur trois chapitres, adopte sur le corpus faisant l’objet de cette étude et la conceptualité qu’il déploie, trois perspectives différentes – lesquelles perspectives sont respectivement d’ordre ontologique (premier chapitre), existentiel ou éthique (second chapitre) et anthropologique (troisième chapitre). La première approche – ontologique – explicite le sens que donne Eckhart aux notions d’être, de néant, d’intellect et d’image, ainsi que la manière dont elles se définissent dialectiquement en rapport les unes avec les autres. Le second chapitre, dont l’approche est existentielle, expose les applications éthiques des concepts abordés au chapitre précédent, analysant la méthode de détachement prescrite par Eckhart pour parvenir à l’état de béatitude. Le troisième et dernier chapitre cherche, quant à lui, à définir de quelle manière l’homme se définit par rapport à l’union à laquelle l’invite Eckhart, et ce autant sur le plan spécifique que sur le plan individuel. / The following dissertation attemps to establish the presence of certain conceptual motives pertaining to the modern conception of subjectivity (as exemplified by the cartesian understanding of the self), in the middle-high german works of Master Eckhart of Hochheim, philosopher, theologian and predicator who was born in 1260 and died in 1328. In order to do so, it develops a three-fold argument taking place over three chapters, each of which presents a different approach - a different perspective - on Eckhart’s thought. The first chapter presents an ontological argument designed to explicitate the meaning of the key eckhartian notions of being, nothingness, intellect and image, whereas the second chapter exploits the existential consequences of Eckhart’s outlook on those notions – consequences which in ethical terms translate into the necessity for the human individual to practice a systematic annihilation of oneself in order to achieve an absolutely pure union with God. The third and last chapter of this dissertation attemps to explicitate de notion of “I” (ich), used by Eckhart to designate the identity that the detached human soul and God share, a type of identity in which we find similarities with the modern conception of the self – conception which Heidegger thought of as being entirely absent from precartesian philosophy.