Stability of cassava flour-based food bars

The consumption of Brazilian cassava has been reduced due to a lack of adjustment to the modern lifestyle. To reverse this trend, new products could be developed specifically targeted to high-value niche markets. Cereal bars stand out as fast food high in nutritional value. A bar formula mimicking cereal bars was prepared using a mixture of Brazilian cassava flour, hydrogenated vegetable fat, dried bananas, ground cashew nuts, and glucose syrup. After being pressed, the bars were dried for 1 hour at 65 °C, packaged in films, and stored under ambient conditions. Its stability was continuously monitored for 210 days in order to ensure its safety and enable its introduction to the market. Texture loss was observed in the packed bars after 90 days of storage, but the sensory characteristics allowed the testers to perceive this tendency after only 30 days of storage. However, chemical, physical, and microbial analyses confirmed that the bars were safe for consumption for 180 days. The results showed that a 45 g cassava flour-based bar enriched with nuts and dried fruits can meet 6% of the recommended daily fiber intake with a caloric value between that of the common cereal bar and that of an energy bar. Adapting the formula with ingredients (fruits, nuts) from different regions of Brazil may add value to this traditional product as a fast food.

Dynamic capabilities as enablers of value co-creation between an MBA school and its students

This study presents an understanding of how a U.S. based, international MBA school has been able to achieve competitive advantage within a relatively short period of time. A framework is built to comprehend how the dynamic capability and value co-creation theories are connected and to understand how the dynamic capabilities have enabled value co-creation to happen between the school and its students, leading to such competitive advantage for the school. The data collection method followed a qualitative single-case study with a process perspective. Seven semi-structured interviews were made in September and October of 2015; one current employee of the MBA school was interviewed, with the other six being graduates and/or former employees of the MBA school. In addition, the researcher has worked as a recruiter at the MBA school, enabling to build bridges and a coherent whole of the empirical findings. Data analysis was conducted by first identifying themes from interviews, after which a narrative was written and a causal network model was built. Thus, a combination of thematic analysis, narrative and grounded theory were used as data analysis methods. This study finds that value co-creation is enabled by the dynamic capabilities of the MBA school; also capabilities would not be dynamic if value co-creation did not take place. Thus, this study presents that even though the two theories represent different level analyses, they are intertwined and together they can help to explain competitive advantage. The MBA case school’s dynamic capabilities are identified to be the sales & marketing capabilities and international market creation capabilities, thus the study finds that the MBA school does not only co-create value with existing students (customers) in the school setting, but instead, most of the value co-creation happens between the school and the student cohorts (network) already in the recruiting phase. Therefore, as a theoretical implication, the network should be considered as part of the context. The main value created seem to lie in the MBA case school’s international setting & networks. MBA schools around the world can learn from this study; schools should try to find their own niche and specialize, based on their own values and capabilities. With a differentiating focus and a unique and practical content, the schools can and should be well-marketed and proactively sold in order to receive more student applications and enhance competitive advantage. Even though an MBA school can effectively be treated as a business, as the study shows, the main emphasis should still be on providing quality education. Good content with efficient marketing can be the winning combination for an MBA school.

Scanning the future of Single Euro Payment Area – towards cashless payment methods

The future of paying in the age of digitalization is a topic that includes varied visions. This master’s thesis explores images of the future of paying in the Single Euro Payment Area (SEPA) up to 2020 and 2025 through the views of experts specialized in paying. This study was commissioned by a credit management company in order to obtain more detailed information about the future of paying. Specifically, this thesis investigates what could be the most used payment methods in the future, what items could work as a medium of exchange in 2020 and how will they evolve towards the year 2025. Changing consumer behavior, trends connected to payment methods, security and private issues of new cashless payment methods were also part of this study. In the empirical part of the study the experts’ ideas about probable and preferable future images of paying were investigated through a two-round Disaggregative Delphi method. The questionnaire included numeric statements and open questions. Three alternative future images were created with the help of cluster analysis: “Unsurprising Future”, “Technology Driven Future” and “The Age of the Customer”. The plausible images had similarities and differences, which were reflected to the previous studies in the literature review. The study’s findings were formed based on the images of futures’ similarities and to the open questions answers that were received from the questionnaire. The main conclusion of the study was that development of technology will unify and diversify SEPA; the trend in 2020 seems to be towards more cashless payment methods but their usage depends on the countries’ financial possibilities and customer preferences. Mobile payments, cards and cash will be the main payment methods but the banks will have competitors from outside the financial sector. Wearable payment methods and NFC technology are seen as widely growing trends but subcutaneous payment devices will likely keep their niche position until 2025. In the meantime, security and private issues are seen to increase because of identity thefts and various frauds. Simultaneously, privacy will lose its meaning to younger consumers who are used to sharing their transaction and personal data with third parties in order to get access to attractive services. Easier access to consumers’ transaction data will probably open the door for hackers and cause new risks in paying processes. There exist many roads to future, and this study was not an attempt to give any complete answers about it even if some plausible assumptions about the future’s course were provided.

Business modeling in turbulent environments

This study presents an agile tool set for the business modeling in companies, entering the turbulent environment. The study’s aim is to explore business modeling techniques and their tooling by utilizing a case study of a Finnish media monitoring company, expanding to the Russian market. This work proposes a tailored “two-approach” of business modeling development that analyzes both the past and future conditions of two key factors of business modeling for companies – internal and external environments. The study explores a case company by investigating the benefits and disadvantages of firm’s present business modeling tools, developing a new tooling and applying it to the case company. Among primary data utilization, such as interviews with media monitoring industry analysts and representatives of the competing companies, and academic experts, study leans up on the comprehensive analysis of Russian media monitoring niche and its players. This study benefits the business modeling research area and combines traditional analysis tools, such as market, PESTLE and competitor analyses, in a systemic manner, with the business modeling techniques. This transformation proceeds through applying of the integrated scenario, heat map and critical design issues’ analyses in the societal, industrial and competitive context of turbulent environments. The practical outcome of this approach is the development of agile business modeling tool set, customizable by company’s requirements.

Crowdfunding as a new funding alternative for early stage start-ups

Attracting outside capital is a common problem for start-up companies. Capital markets define the funding options for companies and firms which suffer the most from these capital market imperfections are small start-up companies. Therefore it is important to study any new funding model which can offer a new solution to this inefficiency of capital markets. This study explains the traditional funding models for start-ups such as founders, friends & family, banks, business angels and venture capitalist. After giving background to traditional start-up funding this study delves into crowfunding (CF) and introduces it as a new funding method. The objective of the thesis is to answer one broad research question: Why and how should start-up companies use CF as an alternative funding method? To properly delve into this, this question has the following sub-questions: What kind of funding alternatives do start-up companies have? What are the pros and cons of CF compared to other funding options? How can start-ups benefit from CF? This study gives background on the rise of CF and the reasons why this new model is needed. Author will explain the different components of CF such as platforms, crowdfunders and projects. Also benefits and challenges of the crowdfunding model are investigated. As a new funding model CF has had to clear out many obstacles from its way. These are, for example, legal and regulatory issues as well education of crowd investors to understand this new investment option. . Start-up entrepreneurs can gain valuable insight from this study. The author has attempted to form best practices and guidelines of how to operate in the CF environment. This study was conducted by performing expert interviews, collecting data from previous studies and performing a content analysis of successful crowdfunding cases. Main findings from the study were that CF has huge potential in funding entrepreneurial projects. It is still a niche way for funding but growing rapidly. CF is earning its place among traditional funding options and has potential to fund projects which otherwise would struggle to find funding. With CF entrepreneur can tap into geographically diverse audience. It is a powerful validation tool for products and ideas and has the power to bring democratic elements to entrepreneurial funding.

Mechanisms underlying Retinoic acid-induced chemoattraction in molluscan neurons

Retinoic acid, a derivative of vitamin A, is known to play diverse roles in development and regeneration. Previous research in the mollusc Lymnaea stagnalis has shown that a gradient of all-trans retinoic acid attracts the growth cones of cultured neurons. The present study investigates the sub-cellular mechanisms within the growth cones of Lymnaea pedal A neurons which mediate the attractive response to a gradient of alltrans retinoic acid. In this study, the mechanism of growth cone turning is shown to be local, as neurites mechanically isolated from their cell body retain the capacity to turn towards an exogenous gradient of all-trans retinoic acid. The turning response is dependent on the initiation of protein synthesis and calcium influx, but does not appear to involve signaling through protein kinase C (PKC). The retinoid X receptor (RXR), which classically functions as a transcription factor, was also shown to be involved in the turning response, functioning locally through a non-genomic pathway. These data show, for the first time in any species, that all-trans retinoic acid's chemotropic action involves a local mechanism involving non-genomic signaling through the RXR. As retinoic acid is known to playa role in regeneration, understanding the mechanisms underlying retinoic acid signaling may lead to further advances in regenerative neuroscience.

Rittermere Farm Craft Studio Fonds, 1951-2006

During the 1950’s, the Rittenhouse family of Vineland in the Niagara Peninsula opened a craft store and studio. Within a short period of time, they realized that resources for the craft of rug hooking were in demand and they began to build their business around this niche. Edna Rittenhouse, the mother, was the wool dyer; Margaret Rowan, the daughter, was the pattern designer; Ted Rowan, the son-in-law, changed careers and became the manager of the family business. The 1960’s were a prosperous time, not only in the Niagara Peninsula, but also for the Rittenhouse business. Edna Rittenhouse had been hooking rugs for decades but she and her family worked at developing and sharing newer techniques with newer materials. Shading manuals were authored and published; students became teachers; creativity abounded in the demand for and the creation of new designs. Instead of using woolen yarn, they were using pure woolen fabric; instead of using a standard cutter, they began using a uniquely designed cutter; instead of using frames, they employed a table top method. The new material and technique resulted in a rug with a smooth, uniform texture and a soft nap. Since many crafters belonged to crafters guilds, Margaret and Ted Rowan began promoting the idea of a guild for rug hookers and in time the Ontario Hooking Craft Guild was also a reality. A joint project between Chatelaine magazine and the Rittermere studio for Canada’s centennial year of 1967 was extremely well received within the circle of hooking crafters and the Rittermere Farm Craft Studio became a North American landmark for crafters. From this point onward the studio had a large customer base not only in North America but also overseas. The studio remained popular until 1984 when Margaret and Ted Rowan decided to retire. The Rittermere name has been preserved in the name of Rittermere-Hurst-Field which is a similar business located in Aurora which is just north of Toronto.

Identification and characterization of retinoic acid-induced morphological and electrophysiological changes in an invertebrate nervous system

The vitamin A metabolite, retinoic acid (RA) is known to play an important role in the development, patterning and regeneration of nervous tissue, both in the embryo and in the adult. Classically, RA is known to mediate the transcription of target genes through the binding and activation ofits nuclear receptors: the retinoic acid receptors (RARs) and retinoid X receptors (RXRs). Recently, mounting evidence from many animal models has implicated a number of RA-mediated effects operating independently of gene transcription, and thus highlights nove~ nongenornic actions of RA. For example, recent work utilizing cultured neurons from the pond snaa Lymnaea stagnalis, has shown that RA can elicit a regenerative response, growth cone turning, independently of "classical" transcriptional activation While this work illustrates a novel regeneration-inducing effect in culture, it is currently -unknown whether RA also induces regeneration in situ. This study has sought to determine RA's regenerative effucts at the morphological and molecular levels by utilizing an in situ approach focusing on a single identified dopaminergic neuron which possesses a known "mapped" morphology within the CNS. These studies show, for the first time in an invertebrate, that RA can increase neurite outgrowth of dopaminergic cells that have undergone a nerve-crush injury. Utilizing Western blot analysis, it was shown that this effect appears to be independent of any changes in whole CNS expression levels of either the RAR or RXR. Additionally, utilizing immunohistochemistry, to examine protein localization, there does not appear to be any obvious changes in the RXR expression level at the crush site. Changes in cell morphology such as neurity extension are known to be modulated by changes in neuronal firing activity. It has been previously shown that exposure to RA over many days can lead to changes in the electrophysiological properties of cultured Lymnaea neurons; however, no studies have investigated whether short-term exposure to RA can elicit electrophysiological changes and/or changes in firing pattern of neurons in Lymnaea or any other species. The studies performed here show, for the first time in any species, that short-tenn treatment with RA can elicit significant changes in the firing properties of both identified dopaminergic neurons and peptidergic neurons. This effect appears to be independent of protein synthesis, activation of protein kinase A or phospholipase C, and calcium influx but is both dose-dependent and isomer-dependent. These studies provide evidence that the RXR, but not RAR, may be involved, and that intracellular calcium concentrations decrease upon RAexposure with a time course, dose-dependency and isomer-dependency that coincide with the RA-induced electrophysiological changes. Taken together, these studies provide important evidence highlighting RA as a multifunctional molecule, inducing morphological, molecular and electrophysiological changes within the CNS, and highlight the many pathways through which RA may operate to elicit its effects.

Elucidation of the Retinoid Signalling Pathway Involved in Axon Guidance in Lymnaea stagnalis and Xenopus laevis

The vitamin A metabolite, retinoic acid (RA), is known to play a crucial role in several developmental processes including axial patterning and differentiation. More recently, RA has been implicated in the regenerative process acting through its classical signaling pathway, the nuclear receptors, retinoic acid receptor (RAR) and retinoid X receptor (RXR), to mediate gene transcription. Moreover, RA has been shown to act as a guidance molecule for growth cones of regenerating motorneurons of the pond snail, Lymnaea stagnalis. Our lab has recently shown that RA can induce this morphological response independent of nuclear transcription, however, the role of the retinoid receptors in RA-induced chemoattraction is still unknown. Here, I show that the retinoid receptors, RXR and RAR, may mediate the growth cones response to the metabolically active retinoic acid isomers, all-trans and 9-cis RA, in Lymnaea stagnalis. Data presented here show that both an RXR and RAR antagonist can block growth cone turning in response to application of both isomers. Because no prior investigations have shown growth cone turning of individual vertebrate neurons, I aimed to show that both retinoic acid isomers were capable of inducing growth cone turning of embryonic spinal cord neurons in the frog, Xenopus laevis. For the first time in Xenopus, I showed that both all-trans and 9-cis RA were able to induce significantly more neurite outgrowth from cultured embryonic spinal cord neurons and induce positive growth cone turning of individual growth cones. In addition, I showed that the presence of the RXR antagonist, HX531, blocked 9-cis RA-induced growth cone turning and the RARβ antagonist, LE135, blocked all-trans RA-induced growth cone turning in this species. Evidence provided here shows for the first time, conservation of retinoic acid-induced growth cone turning in a vertebrate model system. In addition, these data show that the receptors involved in this morphological response may be the same in vertebrates and invertebrates.

Understanding the Intersection of Reformed Faith and Dutch Immigrant Culture in Ontario Independent Christian Schools: Principals’ Experiences and Perspectives

In the aftermath of World War II, a wave of Dutch Reformed immigrants arrived in Ontario, many of whom joined the Christian Reformed Church. Following familiar cultural patterns, history, and their Reformed Christian faith, these immigrants settled in Ontario with remarkable institutional completeness (Breton, 1964). They quickly established independent, parent-operated Christian schools across Ontario. The primary purpose of the schools was to educate children through a comprehensive biblically based school program, yet this religious purpose often intersected with a Dutch immigrant ethnic culture. Van Dijk (2001) states that “the schools were the most important organization in maintaining the religious and ethnic identity of Calvinists” (p. 66). In this qualitative study I explore the intersection of Reformed faith and Dutch Canadian immigrant ethnic culture in Christian schools through the experiential and professional lens of eight retired principals. Employing a theoretical framework informed by Berger’s (1967) Sacred Canopy, I suggest that the intersection of faith and culture was experienced in the schools and was embodied by the schools themselves. Findings point to this intersection being located in the participants’ experience of (a) Dutchness, (b) the struggle for Christian education, (c) the ties that bound the school community together, and (d) the cloud of witnesses that founded and continues to support and encourage the Christian school community. The study offers insight into a Dutch Reformed immigrant group’s experience carving out a niche for themselves on the educational landscape in Ontario. This study also offers suggestions on how Christian schools can broaden their canopy and become more ethnically and denominationally diverse in the future.

Régulation de l’expression du gène Six6 par les facteurs de transcription Lhx2 et Pax6 dans le contexte des cellules souches rétiniennes

La rétinogésèse des vertébrés est la culmination de processus biologiques complexes parfaitement exécutés. Cette délicate orchestration est principalement contrôlée par les facteurs de transcription qui permettent aux progéniteurs rétiniens de proliférer, de s’auto-renouveler et de se différencier de façon appropriée. Les facteurs de transcription à homéodomaine sont les protéines qui sont responsables de la démarcation du site du primordium optique et participeront même à la différenciation tardive des différents types cellulaires de la rétine. Le contrôle génétique concernant l‘activation de l’expression de facteurs de transcription est peu connu. Nous avons étudié les séquences génomique avoisinant le gène Six6 afin d’identifier et mieux comprendre son promoteur. Des expériences d’immunoprécipitation de chromatine et des essais luciférases ont confirmé la liaison et la transactivation synergique du promoteur potentiel de Six6 par Lhx2 et Pax6 in vitro. Cette présente étude confirme et précise également le rôle de Lhx2 au niveau du développement précoce de l’oeil. La compréhension détaillée des réseaux génétiques régulant les progéniteurs rétiniens à former une rétine fonctionnelle est essentielle. En effet, lorsque ces connaissances seront acquises, nous serons en mesure d’appliquer les thérapies cellulaires pour rétablir les fonctions rétiniennes lors de pathologies dégénératives.

Rôle des Cellules Endothéliales Progénitrices dans la Régulation de la Fonction Plaquettaire

Les Cellules Endothéliales Progénitrices ("Endothelial Progenitor Cells", EPCs) sont des précurseurs endothéliaux qui jouent un rôle émergeant en biologie vasculaire. Les EPCs ont été localisées dans le cordon ombilical, la moelle osseuse, le sang périphérique et dans certains tissus régénérateurs. Les interactions des EPCs avec les cellules sanguines et vasculaires peuvent largement influencer leurs propriétés biologiques et dicter leur fonctionnement pendant la réparation endothéliale. Plus spécifiquement, les interactions des EPCs avec les plaquettes circulantes induisent leur migration, leur recrutement et leur différentiation en cellules endothéliales aux sites de lésions vasculaires. Cependant, l’impact d’une telle interaction sur la fonction plaquettaire n’a pas été recherché. Le but de mon projet était de :1) générer des EPCs à partir des cellules mononucléaires du sang humain périphérique ("Peripheral Blood Mononuclear Cells", PBMCs); 2) étudier les interactions adhésives entre les EPCs et les plaquettes; 3) déterminer leur impact sur la fonction plaquettaire et la formation du thrombus et 4) décrire le mécanisme d’action des EPCs sur les plaquettes et le thrombus. Mises en culture sur une surface de fibronectine dans un milieu conditionné, les PBMCs fraîchement isolées possédaient une morphologie ronde et une petite taille. Après cinq jours, les PBMCs adhérentes donnaient naissance à des colonies, puis formaient une monocouche de cellules aplaties caractéristiques des EPCs après dix jours de culture. Les EPCs différenciées étaient positives pour l’Ulex-lectine et l’Acétyle des lipoprotéines de faible densité ("Acetylated Low Density Lipoprotein", Ac-LDL), exprimaient les marqueurs progéniteurs (CD34, P-sélectine, VEGFR2, vWF et VE-Cadhérine) tandis que les marqueurs leucocytaires (CD14, PSGL-1 et L-sélectine) étaient absents. Ces EPCs interagissaient avec les plaquettes activées par un mécanisme dépendant de la P-sélectine plaquettaire, inhibaient l’activation et l’agrégation plaquettaire et réduisaient significativement l’adhésion plaquettaire, principalement par l’action de prostacycline (PGI2). En fait, ceci était associé avec une augmentation de l’expression de la cyclooxygénase-2 (COX-2) et du monoxyde d’azote (NO) synthéthase inductible (iNOS). Toutefois, les effets inhibiteurs des EPCs sur la fonction plaquettaire ont été renversés par une inhibition de la COX et non pas du NO. Bien que les EPCs fussent en mesure de lier les plaquettes via la P-sélectine, leurs effets prédominants étaient médiés essentiellement par une sécrétion paracrine, impliquant la PGI2. Néanmoins, un rapprochement étroit ou un bref contact entre les EPCs et les plaquettes était requis pour que cette fonction soit complètement réalisée. D’ailleurs, cet aspect a été investigué chez des souris déficientes en P-sélectine (P-sel-/-) et chez leurs congénères de phénotype sauvage (Wild Type, WT). Chez les souris WT, les EPCs inhibaient l’agrégation plaquettaire dans le sang complet de manière concentration-dépendante alors que dans les souris P-sel-/-, l’action des EPCs n’avait pas d’effet significatif. De plus, en utilisant un modèle murin de thrombose artérielle, nous avons démontré que l’infusion systémique des EPCs altéraient la formation du thrombus et réduisaient significativement sa masse chez les souris WT, mais non pas chez les souris P-sel-/-. En outre, le nombre des EPCs incorporées au niveau du thrombus et de la paroi vasculaire était visiblement réduit chez les P-sel-/- par rapport aux souris WT. Dans cette étude, nous sommes parvenus à différentier adéquatement des EPCs à partir des PBMCs, nous avons étudié les interactions adhésives entre les EPCs et les plaquettes, et nous avons décrit leur impact sur la fonction plaquettaire et la formation du thrombus. De plus, nous avons identifié la PGI2 comme étant le principal facteur soluble sécrété par les EPCs en culture et responsable de leurs effets inhibiteurs sur l’activation, l’adhésion et l’agrégation plaquettaire in vitro. De surcroît, nous avons élucidé le mécanisme d’action des EPCs sur l’agrégation plaquettaire et la formation du thrombus, in vivo, et nous avons souligné le rôle de la P-sélectine plaquettaire dans ce processus. Ces résultats ajoutent de nouvelles connaissances sur la biologie des EPCs et définissent leur rôle potentiel dans la régulation de la fonction plaquettaire et la thrombogenèse.

Caractérisation du risque associé au virus de l'hépatite E chez le porc

Dans cette étude, la bile d’un porc canadien naturellement infecté par une souche du virus de l’hépatite E (VHE) a été utilisée afin d’inoculer deux groupes de porcelets. Dans l’étude précoce (E), 4 porcelets âgés de 4 semaines et exempts de pathogènes spécifiques (SPF), ont été suivis jusqu’à 14 jours post-inoculation (pi). Dans l’étude tardive (L), 9 porcelets ont été suivis à chaque semaine jusqu’à l’abattage, soit 120 jours pi. À la nécropsie, la présence du VHE a été évaluée dans différents organes à 7, 14 et 120 jours pi. Des porcelets témoins (E=2 et L=3) ont été inoculés par de la bile exempte de VHE. Le virus a persisté chez certains animaux jusqu’à 84 à 105 jours pi dans le sérum malgré la présence d’anticorps IgG anti-VHE dans le sang, suggérant une virémie prolongée. L’excrétion virale dans les fèces s’est étalée également sur une période de 105 jours pi chez certains animaux. De plus, la détection de l’ARN viral dans les organes évalués s’est révélée presque nulle à l’âge d’abattage à l’exception de quelques vésicules biliaires, alors qu’on retrouvait l’ARN viral dans plusieurs organes à 7 et 14 jours pi. Pour évaluer la distribution du VHE chez les porcs commerciaux du Québec, un échantillonnage de porcs de trois abattoirs a été réalisé. Environ 100 échantillons de sang, fèces, foies et bile provenant des mêmes animaux en processus d’abattage ont été prélevés dans chacun des abattoirs, sur des porcs destinés à la consommation humaine. La détection de l’ARN viral et des anticorps du VHE a été réalisée à l’aide d’une RT-PCR nichée et d’un test ELISA adapté pour déceler les anticorps porcins anti-VHE. Chez les porcs d’abattoir, 12,9 % des échantillons de bile contenaient de l’ARN viral du VHE, alors que la détection virale était moindre dans les autres organes. Une séroprévalence en IgG de 26,0 % a été obtenue pour les sérums porcins analysés. Une analyse phylogénétique des différentes souches isolées pendant l’étude a démontré qu’elles sont du génotype 3. Ces données indiquent une exposition potentielle des travailleurs de l’industrie porcine au VHE porcin, notamment par les fèces, le sang et les organes et également pour les consommateurs par le biais des foies.

Altérations métaboliques et nature des acides gras : implication dans la différenciation des cellules régénératives du tissu adipeux

Par la sécrétion d’adipokines, le tissu adipeux blanc viscéral présent chez des patients souffrant d’obésité promeut l’installation d’altérations métaboliques telles que l’intolérance au glucose, la résistance à l’insuline et le diabète de type 2. Les complications cardiovasculaires, en particulier l’athérosclérose, sont les principales causes de mortalité chez les patients atteints de diabète de type 2. Il a été démontré que la fraction vasculaire stromale du tissu adipeux est composée de cellules régénératives dérivées du tissu adipeux (CRTA) et que ces cellules possèdent des caractéristiques des cellules progénitrices stromales (CPS). L’impact de l’intolérance au glucose et du diabète de type 2 sur les adipocytes sont assez bien documentés. Par contre, les conséquences de ces pathologies sur le comportement des CRTA n’ont pas été mesurées d’une façon approfondie. Plus particulièrement, l’impact de ces altérations métaboliques sur le potentiel de différenciation des CRTA en adipocytes et en cellules endothéliales n’a pas été étudié. Ce projet a pour but d’évaluer, dans un modèle murin, l’effet de ces altérations métaboliques sur l’équilibre de la différenciation in vitro des CRTA en adipocytes ou en cellules endothéliales. L’intolérance au glucose et le diabète de type 2 ont été induit chez les souris par la prise de deux diètes riches en acides gras de provenance végétale (DV) ou animale (DA). L’impact de l’origine des acides gras sur la différenciation des CRTA a également été étudié. Pour ce faire, une mise au point de la culture cellulaire des CRTA s’est avérée nécessaire et compte pour une partie de ces travaux de maîtrise. Nos travaux ont démontré en premier lieu, que le DMSO est un agent qui conserve la viabilité et les propriétés progénitrices des CRTA suite à leur congélation. De plus, parmi les matrices testées, le collagène s’est avéré être celle qui conserve le mieux les caractéristiques des progéniteurs et même, qui enrichie la population cellulaire ensemencée en cellules progénitrices. La densité cellulaire des cellules non-adipeuses du tissu adipeux s’avère être significativement plus élevée chez les souris du groupe de la DV comparativement aux souris contrôles. De plus, l’évaluation in vitro de la différenciation adipogénique démontre un potentiel de différenciation plus important pour les CRTA provenant des souris de la DV par rapport au groupe contrôle et à la DA. Cependant, la différenciation en cellules endothéliales est inhibée chez les CRTA de la DV, comparativement à un retard de ce processus pour la DA. Nos travaux suggèrent que le potentiel de différenciation adipogénique et endothéliale des CRTA est affecté par le statut métabolique des souris ainsi que par la nature de la diète. Ces résultats mettent en lumière pour la première fois l’importance d’évaluer le comportement des CRTA en fonction du statut métabolique du donneur, un paramètre pouvant avoir un impact majeur dans l’utilisation des CRTA autologues en thérapie cellulaire pour la réparation de tissus vasculaires chez des patients diabétiques.