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Bortom personlig integritet : En användarstudie av personlig integritet på gratis sociala medier / Beyond privacy : A user study of privacy on free social mediaEngberg, Per January 2016 (has links)
Detta är ett examensarbete som handlar om personlig integritet och användande utav sociala medier. Internet och sociala medier har fått en given del i vår vardag. Dessa sociala medier är gratis för användaren att använda och finansieras därför oftast via reklam som till en stor del baseras på den information användaren laddar upp på dessa tjänster när den använder dem, så kallad riktad reklam. Isbergsmodellen som Facebook bygger på innebär att man som användare inte ska märka av detta när man interagerar med tjänsten. Denna studie ämnar att undersöka om detta kan påverka användarnas personliga integritet och vad användarna anser om denna riktade reklam som baseras på information om dem. Detta studerades via en en webbenkät som distribuerats till unga vuxna inom Stockholmsområdet. Tre stycken djupare intervjuer utfördes även för att få en djupare förståelse kring användarnas beteende och resonemang. Metoden resulterade i 101 enkätsvar. Resultaten tolkas i enlighet med Alan F. Westins teorier om internetanvändarnas attityder till personlig integritet. Användarna i studien har en pragmatisk attityd till personlig integritet på internet och är därför väl medvetna om vad som försegår. Slutsatsen är därför att dessa unga vuxna i Stockholmsområdet inte löper någon risk att få sin personliga integritet kränkt vid användande av sociala nätverks-tjänster. / This thesis is about privacy and the use of social media. The internet and social media has become a given part of our everyday lives. These social media services are free to use and are therefore usually financed via advertising that to a large extent is based on the information that the users have uploaded to these services when they use them, so-called behavioral targeting. The iceberg model that Facebook is based on means that users will not notice this when they interact with the service. This study aims to investigate if this could affect the user's privacy and what the users opinion about targeted advertising is. This was studied via a survey that was distributed on the internet to young adults in the Stockholm area. Three in-depth interviews were also conducted to gain a deeper understanding of the user’s behavior and reasoning. The survey resulted in 101 responses. The results is interpreted with Alan F. Westins theories about privacy attitudes among internet users. The users in this study have a pragmatic approach to privacy on the internet. They are therefore well aware of what is going on behind the scenes. The conclusion is that these young adults in the Stockholm area don’t run any risk of having their privacy violated by using free social networking-services.
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Target your customer's contextually : Explaining contextual targeting’s effect within the banking marketBerlin, Alex, Johnsson, Anton January 2021 (has links)
Purpose: The purpose of this explanatory study was to explain how contextual targeting affects customer attitudes, privacy concerns, trust, and loyalty. Literature Review: The reviewed literature included concepts that are important within the banking market. Such as attitude (cognitive, affective, and conative), privacy concerns, trust, and loyalty. Based on the literature review the authors proposed six hypotheses that together formed the research model. Methodology: A positivistic and deductive research approach was adopted in the form of a quantitative research design. Primary data was collected through an online questionnaire created in Google Forms which generated a total of 132 responses. Descriptive statistics, Cronbach’s alpha, and Pearson's correlation stood as a basis to analyze and interpret the data. Lastly, regression analysis was conducted in order to address the authors' proposed hypotheses stemming from the literature review. Findings: The study found that contextual targeting had a significant positive effect on the three components of attitudes, cognitive, affective, and conative. Contextual targeting did not have a significant positive effect on privacy concerns, rather a negative effect in this study. Trust and loyalty were significantly positively affected by contextual targeting. The findings implied that contextual targeting positively affected visibility, awareness, preferences among customers of banks as well as their final purchase decision. Also, that contextual targeting affected trust and loyalty towards banks positively implying the positive aspects of utilizing the marketing strategy. Keywords - Contextual targeting, Attitudes, Cognitive, Affective, Conative, Privacy concerns, Trust, Loyalty
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Nanotechnologie a biomateriály pro využití v buněčné terapii míšního poranění / Nanotechnology and biomaterials for application in cell therapy of spinal cord injuryVaněček, Václav January 2013 (has links)
New approaches for the treatment of SCI use advances in the fields of nanotechnology, biomaterial science and cell therapy. The results presented in this thesis showed that superparamagnetic iron oxide nanoparticles coated with a stable dopamine-hyaluronane associate can be used for the safe and effective labeling of MSC. Cell labeling efficiency, viability and the relaxivity of the tested particles were significantly better than those obtained with the commercial particles Endorem®. The DPA-HA coated nanoparticles can be used for the noninvasive monitoring of cell therapy using MRI. Furthermore, we showed that SPION can be used for the targeted delivery of MSC to the site of a spinal cord lesion. The labeled cells can be concentrated in the lesion area by means of a magnetic implant. The process of cell targeting depends on the physical characteristics of the magnetic implant as well as on the biological features of the cells and nanoparticles, as we described with a proposed mathematical model. It is possible to modify the properties of the magnetic system, e.g. by changing the shape or size of the magnet, thus tuning the magnetic force distribution and the gradient of the magnetic field necessary for effective cell targeting. A promising therapeutic strategy for the treatment of spinal cord injury is the...
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Targeted Disruption of the Glutaredoxin 1 Gene Does Not Sensitize Adult Mice to Tissue Injury Induced by Ischemia/Reperfusion and HyperoxiaHo, Ye Shih, Xiong, Ye, Ho, Dorothy S., Gao, Jinping, Chua, Balvin H.L., Pai, Harish, Mieyal, John J. 01 November 2007 (has links)
To understand the physiological function of glutaredoxin, a thiotransferase catalyzing the reduction of mixed disulfides of protein and glutathione, we generated a line of knockout mice deficient in the cytosolic glutaredoxin 1 (Grx1). To our surprise, mice deficient in Grx1 were not more susceptible to acute oxidative insults in models of heart and lung injury induced by ischemia/reperfusion and hyperoxia, respectively, suggesting that either changes in S-glutathionylation status of cytosolic proteins are not the major cause of such tissue injury or developmental adaptation in the Glrx1-knockout animals alters the response to oxidative insult. In contrast, mouse embryonic fibroblasts (MEFs) isolated from Grx1-deficient mice displayed an increased vulnerability to diquat and paraquat, but they were not more susceptible to cell death induced by hydrogen peroxide (H2O2) and diamide. A deficiency in Grx1 also sensitized MEFs to protein S-glutathionylation in response to H2O2 treatment and retarded deglutathionylation of the S-glutathionylated proteins, especially for a single prominent protein band. Additional experiments showed that MEFs lacking Grx1 were more tolerant to apoptosis induced by tumor necrosis factor αplus actinomycin D. These findings suggest that various oxidants may damage the cells via distinct mechanisms in which the action of Grx1 may or may not be protective and Grx1 may exert its function on specific target proteins.
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Nanoparticules polymères ciblant le récepteur CXCR3 : élaboration et évaluation sur modèles de tumeur / CXCR3-targeting polymer nanoparticles : synthesis and evaluation on tumor modelsRodrigues, Laura 10 July 2018 (has links)
La thèse présentée porte sur l’élaboration de nanoparticules polymères fonctionnalisées par le ligand SCH546738 afin de cibler le récepteur CXCR3 surexprimé sur les cellules cancéreuses. La synthèse des copolymères à blocs Poly(triméthylène carbonate)-b-Poly(éthylène glycol) (PTMCb- PEG) et PTMC-b-PEG-SCH546738, puis leurs auto-assemblages dans l’eau avec des pourcentages différents de l’un par rapport à l’autre et enfin l’activité biologique de ces nanoparticules in vitro ont été réalisés. Une série de PTMC-b-PEG de fraction hydrophile massique f différentes (entre 34 et 6%) ont été obtenus par polymérisation par ouverture de cycle (ROP) du monomère triméthylène carbonate (TMC) amorcée par un PEG (MW= 2000 g/mol). Les études d’auto-assemblage ont montré que la fraction hydrophile était liée à la morphologie des objets obtenus (micelles et vésicules) et que la taille et la morphologie pouvaient être modulées en fonction du protocole utilisé. Des PTMC-b-PEG-SCH546738 ont été obtenus par couplage convergent entre le PEG-SCH546738 et le bloc PTMC. Le co auto-assemblage entre les copolymères fonctionnalisés et non fonctionnalisés a été réalisé par nanoprécipitation contrôlée par un système de microfluidique qui permet d’obtenir des polymersomes monodisperses de tailles contrôlées. Le pourcentage molaire de SCH546738 en surface des polymersomes a été fixé à 5, 10 et 20 % et à l’aide d’une nanoparticule contrôle ces échantillons ont pu être testés in vitro sur cellules HEK 293 et U87 surexprimant le CXCR3-A. L’influence du ligand et son pourcentage sur l’internalisation des nanoparticules à différents temps et sur le blocage des voies de signalisation des cellules cancéreuses ont été observés. / This thesis deals with the elaboration of polymeric nanoparticles functionalized by the ligand SCH546738 to target the CXCR3 receptor overexpressed in human healthy or tumoral cells. Poly(trimethylene carbonate-b-Poly(ethylene glycol) (PTMC-b-PEG) blocks copolymers and PTMC-b-PEG-SCH546738 synthesis, then their self-assembly with different ratios in water, and finally biological activity in vitro of these different nanoparticles were studied. A serie of PTMC-b-PEG with different hydrophilic mass fractions f (between 34 and 6%) were obtained by ring opening polymerization (ROP) of trimethylene carbonate (TMC) initiated by a block PEG (MW: 2000 g/mol). Self-assembly studies showed that the hydrophilic mass fraction was related to the morphology of the nano objects (micelles and vesicles) and that size and morphology of nano objects can be changed by the self-assembly protocol. PTMC-b-PEG-SCH546738 were obtained by the convergent coupling between PEG-SCH546738 and PTMC block. The co self-assembly of functionalized and not functionalized copolymers was done by nanoprecipitation controlled by a microfluidic system that allows monodisperse polymersomes with controlled size to be produced. The molar percentage of SCH546738 at the surface of polymersomes was fixed at 5, 10 and 20 %, and with the control nanoparticle, these samples were tested in vitro on HEK 293 and U87 cells overexpressing the CXCR3-A. The influence of the ligand and its percentage on nanoparticles internalization and signaling pathways blocking on cells were analyzed.
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The Shiga Toxin B-Subunit : a Promising Scaffold for the Targeting of Tumor Specific Glycosphingolipids / Exploitation de l’échafaudage moléculaire de la sous-unité B de la Toxine de Shiga pour le ciblage des glycosphingolipides tumorauxMurarasu, Thomas 13 December 2017 (has links)
Le cancer représente la second cause de décès au monde. Le développement de traitements innovants contre le cancer repose aujourd’hui sur l’identification de biomarqueurs des tumeurs et le développement de produits thérapeutiques capables de reconnaitre ces marqueurs de façon spécifique. Ces produits thérapeutiques de nouvelles générations ont le potentiel d’éliminer spécifiquement les cellules tumorales et donc de réduire les effets secondaires des traitements ainsi que les risques de rechute. Malheureusement, un certain nombre de patients ne peuvent bénéficier de ces traitements, du fait de l’absence de biomarqueurs connus à la surface de leur tumeur. Ce projet a ainsi pour ambition de développer de nouvelles thérapies ciblées en exploitant une nouvelle classe de biomarqueurs et ainsi de venir enrichir l’arsenal thérapeutique disponible pour le traitement des cancers. / Cancer is the second cause of death worldwide. Recent advance in cancer treatments involved the identification of cancer biomarkers and the development of efficient therapeutic products able to specifically recognize them. This new class of products has the ability to specifically target tumor cells, with the major advantages to decrease or abolish treatments side effects and relapses of the disease. Unfortunately, a certain number of patients do not respond to those treatments lacking the expression of those biomarkers on their tumor. This project aims at developing new targeted therapies by exploiting a new class of cancer biomarkers, which would potentially extend the therapeutics options against cancer.
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Stratégies de ciblage des macrophages alvéolaires pour l’administration de glucocorticoïdes / Targeting strategies for glucocorticoid administration to alveolar macrophagesPinheiro do nascimento, Ludmila 15 July 2019 (has links)
Au cours de ce travail de thèse nous avons proposé une stratégie de ciblage des macrophages alvéolaires afin d’y vectoriser des glucocorticoïdes. Une prodrogue de budésonide, le palmitate de budésonide (BP) a été synthétisée dans le but de prolonger sa demi-vie dans les poumons après inhalation. Des nanoparticules PEGylées de BP ont été développées et étudiées pour obtenir une formulation stable avec des caractéristiques physico-chimiques appropriées et un taux de charge élevé pour pénétrer dans les macrophages alvéolaires, cellules centrales dans l'inflammation pulmonaire. Des tests in vitro sur les macrophages RAW 264.7 ont confirmé l'activité anti-inflammatoire et l'absence de cytotoxicité des nanoparticules. Celles-ci ont ensuite été séchée au sein de microparticules Troyennes obtenues par atomisation-séchage afin de faciliter leur administration pulmonaire sous forme de poudres et libérer les nanoparticules à proximité des alvéoles pulmonaires. Les microparticulessphériques creuses contenant de 0 % à 20 % de nanoparticules de BP présentent des diamètres aérodynamiques et une fraction de particules fines appropriés pour la délivrance pulmonaire. Les études pharmacocinétiques in vivo montrent des concentrations élevées et prolongées de budésonide dans les poumons, avec de faibles concentrations plasmatiques. Dans la deuxième partie de cette thèse, une autre stratégie de ciblage des macrophages a été évaluée par la décoration de la surface des nanoparticules avec du mannose. Après la synthèse d'un lipide mannosylé, des nanoparticules ont été formulées et caractérisées, démontrant un taux de charge élevé et une bonne stabilité jusqu'à 30 jours. Des tests in vitro sur les macrophages RAW 264.7 ont montré que la présence du mannose à la surface augmente l'internalisation des nanoparticules d’un facteur 2 après 48 h d'incubation, par rapport aux nanoparticules PEGylées. / This work focuses on strategies to target glucocorticoids to alveolar macrophages. We have synthesized a budesonide prodrug, budesonide palmitate (BP), increasing its lipophilicity to extend drug half-life in the lungs. BP PEGylated nanoparticles were developed and studied to obtain a stable formulation with suitable physicochemical characteristics and high drug loading to enter alveolar macrophages, key players in lung inflammation. In vitro tests on RAW 264.7 macrophages confirmed the anti-inflammatory activity and absence of cytotoxicity of nanoparticles. These were then encapsulated into Trojan microparticles obtained by spray-drying to facilitate their delivery to the lung as dry powders and release nanoparticles directly to the pulmonary alveoli. Spherical hollow microparticles containing from 0 % to 20 % of BP nanoparticles presented suitable aerodynamic diameters and fine particle fraction for lung delivery. In vivo pharmacokinetic studies demonstrated high and extended budesonide concentrations in the lungs, with low plasma concentrations. In the second part of this thesis, another macrophage targeting strategy was assessed by decoration of nanoparticle surface with mannose. After synthesis of a mannosylated lipid, nanoparticles were formulated and characterized, demonstrating high drug loading and stability up to 30 days. In vitro tests on RAW 264.7 macrophages showed that the presence of mannose on the surface increases nanoparticles internalization 2 fold after 48 h incubation, as compared with PEGylated nanoparticles.
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La valence du ligand du récepteur à la transferrine 1 (TfR1) détermine son routage intracellulaire / The Transferrin Receptor 1 (TfR1) Ligand's Valency Determines its Intracellular RoutingMarchal, Michelle 18 November 2019 (has links)
Le récepteur à la transferrine (TfR1) est un récepteur très bien conservé au cours de l’évolution qui permet l’entrée du fer (Fe) lié à la transferrine (Fe-Tf) dans les cellules. Une fois internalisé, le fer se détache de la Tf et est exporté dans le cytoplasme tandis que le complexe Tf/TfR1 est recyclé à la membrane plasmique. Le TfR1 est internalisé par un mécanisme clathrine dépendant et peut être soit recyclé à la membrane plasmique par la voie rapide, soit être dirigé vers le compartiment endosomal de recyclage (ERC). Une fois dans l’ERC, le TfR1 peut être soit recyclé à la membrane plasmique par la voie lente, soit être dirigé vers les lysosomes. De nombreuses protéines régulent le routage des protéines internalisées comme les protéines Rab. Il s’agit de petites GTPases impliquées dans les échanges moléculaires entre les différents compartiments cellulaires.Etant la principale voie d’entrée du fer dans la cellule,le TfR1 est exprimé par la plupart des cellules et est surexprimé par les cellules hautement prolifératives dont certaines cellules cancéreuses. Le TfR1 est très étudié comme cible thérapeutique dans le développement de nouvelles stratégies anti-cancéreuses. A24 est un anticorps murin anti-TfR1 dont l’action anti-proliférative et pro-apoptotique ont été démontrées dans plusieurs hémopathies malignes.Nous nous sommes demandés comment la fixation de A24 sur le TfR1 peut produire des effets différents de la fixation de la Fe-Tf. En générant un fragment Fab, nous avons d’abord démontré que le routage du TfR1 dépend de la valence de son ligand. Nous avons ensuite démontré que la fixation monovalente du TfR1 par la Fe-Tf et le Fab induisent son recyclage sans passer par l’ERC. Nous avons également démontré que la fixation divalente du TfR1 par A24 induit son routage depuis l’ERC vers les lysosomes par une voie dépendante de Rab12. / The transferrin receptor (TfR1) is a highly conserved receptor that allows the entry of iron (Fe) linked to transferrin (Fe-Tf) into cells. Once internalized, Fe separates from the Tf and is exported in the cytoplasm whereas the complex Tf/TfR1 is recycled to the cell membrane. TfR1 is internalized by a clathrin mediated endocytosis and can be either recycled to the cell membrane through the rapid pathway or be routed towards the endosomal recycling compartment (ERC). Once in the ERC, the TfR1 can be either recycled to the cell membrane through the slow pathway or be routed towards lysosomes. Many proteins regulates the routing of internalized proteins such as Rab proteins. They are small GTPases involved in molecular exchanges between the different cellular compartments.Being the main mode of entry of iron into cells, TfR1is expressed by almost every cells and is overexpressed by highly proliferative cells including some cancer cells. TfR1 is extensively studied as a therapeutic target for the development of new anti-cancer strategies. A24 is a murine anti-TfR1 whose anti-proliferative and pro-apoptotic roles were demonstrated in several hematological malignancies.We wondered how A24 binding on TfR1 can produce different effects from Fe-Tf binding. By the manufacturing of a Fab fragment, we first demonstrated that TfR1 fate depends on its ligand’s valency. We then demonstrated that the monovalent binding of TfR1 with Fe-Tf or the Fab leads to its recycling without going through the ERC. We also showed that the divalent binding of the TfR1 by A24 leads to its routing from the ERC to lysosomes through a Rab12 dependent pathway.
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Developing Thyronamine Analog Pharmaceuticals Targeting TAAR1 to Treat Methamphetamine AddictionWahl, Troy Andrew 19 July 2013 (has links)
As a part of the overall program in the Grandy laboratory at Oregon Health & Science University (OHSU), studying the underlying chemical biology of methamphetamine (Meth) addiction, this dissertation reports on the development of six new thyronamine analogs which were synthesized and assayed against trace amine associated receptor 1 (TAAR1), giving preliminary results consistent with the analogs being inverse agonists. Due to highly variable TAAR1 expression levels in the assays, based on inter-assay response to control Meth stimulation as well as other possible factors, kinetic models were developed to qualitatively explain the assay results. The models set approximate limits on the analogs' binding and disassociation rates relative to those of Meth. Analysis of the assays also provides more evidence of TAAR1's basal activity. Based on the models, the conversion rate of ligand-free inactive TAAR1 to ligand-free active TAAR1 is less than 6% of the binding rate of Meth to TAAR1. The models also suggest that the inverse agonists bind to the inactive ligand-free form of TAAR1 between 10 and 100 times faster than Meth binds to the inactive ligand-free form of TAAR1. Three of the new analogs, G5-110s8, G5-112s5, and G5-114s5, bind to the ligand-free active form of TAAR1 faster than they bind to the inactive ligand-free form of TAAR1. The models do not suggest an upper limit on the binding rate of those 3 analogs to the ligand-free active form of TAAR1. A control assay lacking TAAR1 revealed an electrophysiological off-target effect caused by G5-109s8. Also, a novel synthetic route was developed for ET-92, the lead compound for this project, which reduced the number of synthetic steps from 14 to 5 and improved the overall yield from 15.3% to 18.3% (77.4 mg) with the hope that further improvements in yield are possible.
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Ciblage de l'activité de l'interféron alpha : de la preuve de concept à l'activité biologique / Cell-specific targeting of interferon alpha activityPaul, Franciane 24 November 2016 (has links)
Le ciblage de l’activité de l’IFNα est une stratégie développée afin d’augmenter l’index thérapeutique de cette cytokine, dont l’efficacité requiert de fortes doses au site d’action, responsables d’une toxicité systémique. Du fait de l’expression ubiquitaire de son récepteur, le ciblage de l’IFNα par immunocytokine est limité. En se basant sur le concept d'immunocytokine et utilisant un IFNα muté, peu actif, une efficacité de ciblage de 3 log a pu être obtenue, dans le système humain et murin, grâce au rétablissement de l'activité de l'IFNα sur les cellules ciblées. Ces IFNα ciblés sont doués d'une activité biologique, notamment antitumorale, dont la cible cellulaire reste à déterminer. Une stratégie inverse, en cours d'optimisation, permet d'inhiber l’activité des IFN-I spécifiquement sur les cellules ciblées. Cette double stratégie de ciblage de l’activité et de l’inhibition de l’IFN devrait permettre de déterminer les cibles des effets bénéfiques et néfastes des IFN-I, avec des applications thérapeutiques éventuelles. / Targeting IFN activity is a strategy developed to increase the therapeutic index of thiscytokine, whose efficiency requires high doses to site of action, responsible for systemictoxicity. Due to the ubiquitous expression of its receptor, the targeting efficiency of IFNbasedimmunocytokine is limited. Using a mutated IFNα, poorly active, a 3 log targetingefficiency was achieved, in the human and mouse system, by restoring the activity of IFNα ontargeted cells. The biological activity of these targeted IFNα include an antitumoral effect,the cellular target remains to be determined. A reverse strategy being optimized, can inhibitIFN-I activity specifically on targeted cells. This dual targeting strategy of the activity andinhibition of IFN should identify the targets of beneficial and deleterious effects of IFN-I,with possible therapeutic applications.
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