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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Příprava receptury bezlepkového chleba obohaceného o vybrané antioxidanty a posouzení jeho senzorické hodnoty

PECHOVÁ, Klára January 2018 (has links)
Bread has been one of the basic foodstuffs for more than 30,000 years. It´s prepared mainly by baking, where gluten plays an important role. Gluten is important for holding the gas in the dough to achieve the desired structure, texture and volume. At a time when agriculture began to develop, a disease of gluten began to emerge. One of the best known is the intolerance of gluten, the so-called celiac disease, which affect sapproximately 1 % of the world's population. The cause is gluten-rich proteins (prolamins and glutelins), found in wheat, rye, barley and oats. The second known diseaseis gluten allergy, which is often confused with celiac disease. The difference consist in a different autoimmune reaction to the presence of glucose, when the immunization on glucose produces IgE immunoglobulin and does not damage the small intestine mucosa The only possible treatment for patiens with a dinase is a strict gluten-free diet. Gluten-free breads and pastries are one of the main foods for celiac and allergy sufferers. Preparing a dough without gluten is difficult. Proper selection of raw materials plays an important role in meeting sensory properties. The aim of the diploma thesis was to prepare suitable recipe senriched with selected sources of antioxidants. In total, six different recipes were prepared, both from cereal gluten-free flour and legumes flour. Curcuma and red onion skin were selected sources of antioxidants. In the practical part a sensory evaluation of all samples of bread is performed. There was a positive evaluation of the questionnaire itself. When to Cheb the suitability of raw materials and procedures for dough preparation and baking. Based on the DPPH and FRAP tests, antioxidant aktivity was evaluated for all gluten-free bread. Bread senriched with red onion skin have the highest antioxidant activity in both basic bread and basic bread with legume flour. Thus, it can be said that onion skin effectively increase antioxidant activity. In the final part, a financial evaluation of all six types of gluten-free bread was made on the basis of raw materials used as compared to those already purchased in the shop. Based on this finding, it can be said that home preparation is a cheaper option.
112

Výběr bezlepkových potravin z pohledu diagnostikovaného celiaka / Selection of gluten-free food from the perspective of diagnosed celiac

Musilová, Iveta January 2018 (has links)
This diploma focuses on the selection of gluten-free foods from the perspective of a diagnosed celiac. In the theoretical part is described the history of celiac disease, anatomy and physiology of small intestine, pathogenesis, manifestation and forms of celiac disease, diagnosis, screening and complications from celiac disease. It also describes a treatment of celiac disease which shows inappropriate and appropriate aliments in gluten free diet. One chapter deals with labeling of gluten free foods in the Czech Republic and in Canada. There is also a comparison of the Czech Republic and Canada regarding health care, government and restaurants offering gluten free dishes. The aim of the research is to map the selection of gluten free foods in people with diagnosed celiac disease, the second target is to explore differences in food selection in the Czech Republic and Canada. The third objective is focused on factors influencing the choice of gluten free foods. The research was conducted through a questionnaire survey. The survey was filled in the Czech Republic by 78 celiacs and in Canada by 56 celiacs. In the Czech Republic the survey was online on page named Celiake and Mladí Celiaci on Facebook. The Canadian survey was online on page The Celiac scene on facebook and filled out by costumers in...
113

Prevalencia e aspectos clinicos da associação entre diabetes mellitus tipo 1 e doença celiaca / Prevalence and clinical aspects of type 1 diabetes mellitus and celiac disease association

Whitacker, Fatima Cristina de Freitas 20 February 2008 (has links)
Orientadores: Gil Guerra Junior, Gabriel Hessel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-11T04:12:05Z (GMT). No. of bitstreams: 1 Whitacker_FatimaCristinadeFreitas_M.pdf: 1719204 bytes, checksum: 7c00e2334204e8bd5e787cd47276ce2f (MD5) Previous issue date: 2008 / Resumo: Justificativa: Há quatro décadas é conhecida a associação entre Diabetes mellitus tipo 1 (DM1) e doença celíaca. Entretanto, a manifestação predominantemente atípica desta doença em diabéticos, dificulta seu diagnóstico e o reconhecimento de possíveis efeitos desta associação no controle do diabetes. Objetivos: Estimar a prevalência da associação entre DM1 e doença celíaca e verificar a presença de sintomas da doença celíaca, a ocorrência de outras doenças auto-imunes entre os pacientes e seus parentes de primeiro grau e as possíveis influências da doença celíaca no controle do diabetes. Casuística e métodos: Estudo transversal com 195 pacientes com DM1, que responderam um questionário sobre a presença de sintomas gastrintestinais e a ocorrência de doenças auto-imunes em familiares. Foi dosada a IgA e pesquisado o anticorpo anti-endomísio (EMA). Os pacientes com EMA positivo foram submetidos à biópsia intestinal. Aqueles com doença celíaca confirmada por biópsia (grupo casos) foram pareados com pacientes apenas diabéticos (grupo controle) segundo idade no momento da triagem, tempo de duração do diabetes e gênero. Resultados: O EMA foi positivo em nove pacientes. Em sete a biópsia confirmou DC (prevalência de 4%). No pareamento de casos (DM1 e doença celíaca) e controles (somente DM1), os sintomas gastrintestinais foram significativamente mais freqüentes no grupo casos, porém não houve diferença entre os grupos quanto ao controle do diabetes. Conclusões: A prevalência de doença celíaca neste grupo de pacientes com DM1 foi de 4%. A amostra de pacientes celíacos apresentou predomínio de sintomas gastrintestinais e a presença de doença celíaca não interferiu no controle do diabetes / Abstract: Justify: There were four decades that the association between Diabetes Mellitus type 1 (DM1) and celiac disease is known. However, the manifestation of celiac disease in diabetic patients is predominantly atypical, what difficult its diagnosis and the recognition of possible effect of this association in the control of diabetes. Objectives: To estimate the prevalence of DM1 and celiac disease association and to verify the existence of celiac disease symptoms, the occurrence of other autoimmune diseases among the patients and their first-degree relatives and the possible influences of celiac disease in diabetes control. Patients and methods: It was done a cross-sectional study with 195 patients that ansewered a questionnaire about gastrintestinal symptoms and the occurrence of autoimmune diseases in theirs first-degree relatives. IgA was measured and antiendomysial antibody (EMA) screened. The patients with positive EMA were submitted to intestinal biopsy. Those with celiac disease confirmed by biopsy (case group) were paired with DM1 patients without celiac disease (control group) according to age at the screening, time of diabetes duration and gender. Results: EMA was positive in nine patients. In seven of them the biopsy confirmed celiac disease (4.0%). Comparing the cases with controls, the gastrointestinal symptoms were significantly more frequent in the first group and there was no difference between the groups regarding to the control of diabetes. Conclusions: The prevalence found was 4.0%. This sample of celiac patients showed a predominance of gastrointestinal symptoms and the celiac disease did not influence the diabetes control / Mestrado / Pediatria / Mestre em Saude da Criança e do Adolescente
114

Detecção e quantificação de glúten em alimentos industrializados por técnica de ELISA / Detection and quantification of gluten in processed food by ELISA

Rafael Plaza da Silva 10 November 2010 (has links)
A doença celíaca (DC) é uma doença inflamatória induzida pela ingestão de glúten em indivíduos geneticamente predispostos e seu tratamento é baseado em uma dieta sem glúten por toda a vida. A doença celíaca refratária é um problema comum que afeta de 10% a 19% dos pacientes célicos tratados. Provavelmente, a contaminação da dieta por glúten é uma das razões principais para a persistência de sintomas em pacientes celíacos tratados, assim como a ingestão inadvertida de glúten, devido a rotulagem incorreta. Assim, o objetivo deste estudo foi avaliar a confiabilidade dos rótulos dos alimentos brasileiros processados, através de testes de contaminação de glúten nos seguintes grupos (a) produtos \"livres de glúten\" - preparados especificamente para a população celíaca; (b) produtos \"naturalmente sem glúten\" feitos com arroz, milho, soja e mandioca, utilizados por toda a população e (c) produtos rotulados com \"contém glúten\", mas que não apresentam glúten em sua composição no rótulo. Foram analisados 213 produtos alimentícios agrupados em: 115 produtos do grupo \"sem glúten\"; 86 produtos do grupo \"naturalmente sem glúten\" e 12 produtos do grupo rotulados com \"contém glúten\". O teor de glúten foi detectado e quantificado por ELISA-R5 (Ridascreen®gliadin) e os resultados foram expressos em ppm e mg/100 g de alimento. A linha de corte foi estabelecida em 20 ppm para a contaminação de glúten. Todas as contaminações por glúten foram confirmadas por Western-blotting. Resultados: (a) alimentos livres de glúten 15 das 115 (13%) apresentaram contaminação por glúten (20 ppm), (b) grupo de alimentos naturalmente sem glúten - 8 de 86 (9,3%) apresentaram contaminação por glúten (20 ppm); (c) grupo de alimentos rotulados com contem glúten - somente 2 de 12 (16,7%) apresentaram contaminação por glúten (20 ppm). A análise de Western-blotting confirmou 36 das 38 (95%) contaminações encontradas no ELISA-R5. CONCLUSÕES: Ambos os grupos de alimentos \"sem glúten\" e \"naturalmente sem glúten\" comercializados no Brasil apresentaram razoável porcentagem de contaminação por glúten, o que dificulta a realização de uma dieta adequada ao paciente celíaco. O grupo de alimentos rotulado \"com glúten\" não apresentou 100% de contaminação, o que revela que a rotulagem desses produtos deve ser feita como uma medida preventiva. Uma maior chance de contaminação pelo glúten foi observada para os produtos a base de arroz (13,6x), soja (13,3x) e milho (9,3x), mas não naqueles à base de mandioca. Em média, encontramos 10,8% (23 de 213) de contaminação de glúten para os alimentos analisados, um panorama positivo para a população brasileira celíaca, principalmente devido ao uso da mandioca, uma alternativa para a farinha de trigo. No entanto, a contaminação de glúten encontrada mostra a importância da quantificação de glúten em todos os alimentos industrializados. / Celiac disease (CD) is an inflammatory disorder induced by ingestion of gluten in genetically predisposed individuals and its treatment is based on a life-time gluten-free diet. Nonresponsive celiac disease is a common problem affecting from 10% to 19% of treated celiac patients. Probably a gluten contamination in diet is one of the major reasons for symptoms persistence in celiac patients as well as an inadvertent gluten intake due to a misleading nutritional label. The aim of this study was to evaluate the reliability of Brazilian processed food labels by testing gluten contamination in (a) gluten-free products - prepared specifically for the celiac population; (b) in naturally gluten-free products made with rice, corn, soy bean and cassava and used by all population and (c) in not gluten-free products labeled to contain gluten but not having it in their composition. We analyzed 213 food samples grouped accordingly to its type: 115 samples of \"gluten-free food, 86 samples of \"naturally gluten-free food and 12 samples of not-gluten free labeled products. The gluten content was detected and quantified by ELISA-R5 (Ridascreen® Gliadin) and the results were expressed in ppm and mg/100 g of food. A cut-off line was established in 20 ppm for gluten contamination. All gluten contaminations were confirmed by Western-blotting. Results: (a) Gluten-free foods - we found 100 of 115 samples (87%) with no contamination (< 20 ppm) and 15 of 115 (13%) showed gluten contamination 20 ppm; (b) Naturally Gluten-free foods - we found 78 of 86 samples (90,7%) showing no contamination (< 20 ppm) and 8 of 86 (9,3%) with gluten levels 20 ppm; (c) Not gluten-free foods - we found 10 of 12 samples (83,3%) showing no contamination (< 20 ppm) and 2 of 12 (16,7%) with gluten contamination 20 ppm. The Western-blotting analysis confirmed 36 of 38 (95%) contaminations found in the ELISA-R5. CONCLUSIONS: Both \"gluten-free and \"naturally gluten-free foods commercialized in Brazil have presented some gluten contamination making a restricted gluten-free diet hard to be achieved by the celiac population. Unexpectedly the not gluten-free group was not entirely contaminated showing a preventive measure in labeling by food companies. A higher odds ratio for gluten contamination was observed for products made with rice (13.6), soy bean (13.3) and corn (9.3) but not to cassava products (not significant). In general, we found a 10.8% (23 of 213) of gluten contamination for all food products analyzed, a positive panorama for the Brazilian celiac population mainly due to cassava products, an alternative for wheat starch. Nevertheless the gluten contamination found here leads us to the importance for a gluten quantification in all industrialized food to guarantee an appropriated diet to the Brazilian celiac group
115

Cytotoxic lymphocytes in children's cow's milk sensitive enteropathy of delayed type

Augustin, M. (Merja) 10 May 2005 (has links)
Abstract Food hypersensitivities are becoming increasingly common worldwide. Previous studies indicate that cell mediated immunity has a role in delayed paediatric gastrointestinal food hypersensitivities, but the exact pathogenetic mechanisms are unknown. Cytotoxic activation of T-lymphocytes is known to play an important role in the pathogenesis of celiac disease (CD). The pathogenetic mechanisms of cow's milk protein sensitive enteropathy (CMSE) are largely unknown. CMSE is a non-IgE related type of food hypersensitivity with variable gastrointestinal symptoms but no visible mucosal abnormalities on light microscopy. The diagnosis is based on an open or blinded elimination/challenge test, as the endoscopic, histological and laboratory findings are generally non-specific. This thesis aims to characterize the role of lymphocyte cytotoxicity in the pathogenesis and diagnosis of CMSE in preschool and school aged children, including comparison with CD where the pathogenetic significance of cytotoxicity is well established. The study cohort consisted of 151 children, including 57 with untreated CMSE, 18 with treated CMSE, 24 with CD, and 52 controls. Using immunohistochemistry, the mucosal expressions of cytotoxic T cell-restricted intracellular antigen type 1 (TIA-1), perforin, granzyme A and B were analysed in the duodenal bulb and descending duodenum. Intraepithelial T-lymphocytes were labelled with CD3, alpha/beta and gamma/delta T cell receptor antigens. To determine the rates of overall and epithelial apoptosis as well as proliferation, the immunohistochemical TUNEL technique, M30 and Ki-67 antibodies were used. Serum levels of granzymes, CD30 and soluble Fas were studied using ELISA method. The number of intraepithelial lymphocytes with TIA-1, perforin and granzyme A containing granules was increased in CMSE. This increase was related to antigen challenge and not a constitutional abnormality. The cytotoxic reaction in CMSE differed from that in CD by being of lesser magnitude, concerning predominantly the descending duodenum and not showing signs of cytotoxicity related epithelial destruction. The serum levels of GrA, GrB and CD30 were increased in both CMSE and CD, correlating with the number of duodenal CD3+, alpha/beta and gamma/delta+ intraepithelial lymphocytes. The results strongly support the role of cell-mediated immunity in the pathogenesis of CMSE. Mucosal cytotoxic activation seems to be manifested by the release of cytoxicity related proteins in serum. This provides a new approach to the monitoring of intestinal immune activation which could help in diagnosis and in objectively monitored treatment response.
116

Impact of Whole Grain Consumption Compliance on Gluten Sensitivity and Bowel Health

Roberts, Sarah Anne 01 January 2015 (has links)
While many health benefits have been associated with increased whole grain consumption, current researchers have not considered if the consumption of whole grains in currently recommended or higher amounts actually leads to health problems, specifically to a correlated increase in gluten sensitivity. The purpose of this study was to determine if diets high in whole grains or those that met the recommended daily intake of whole grains help minimize or increase gluten sensitivity, and when whole grains are consumed as recommended if they cause more harm than good. The theoretical basis for this quantitative, cross sectional design was the precaution adoption process model, allowing for the examination of preventive behaviors as a series of cognitive steps over time. Individuals (N = 5,746) from the National Health and Nutrition Examination Survey 2007 to 2012 were assessed for daily intake of whole grains before and after the release of the 2010 Dietary Guidelines for Americans, and from 2007 to 2010 for bowel health and sensitivity to whole grains. SAS correlations and regression analysis at p < .05 were analyzed. There was an increase in whole grain intake by 7.4% and in bowel sensitivity with 50% reporting increases in gas, but more data are needed to determine exact amounts that caused these increases in symptoms. Understanding the complete picture, policy makers and others will be more informed about current recommendations and the way that Americans eat, as well as if changes are needed for the future.
117

Exploring Dietary Sacrifice in Intimate Relationships for Couples with Celiac Disease

Alley, Lindsey Marie 30 March 2015 (has links)
Prior research on eating behaviors has shown that romantic partners actively merge their dietary preferences throughout the course of a relationship and find significant value in cooking and eating the same foods together at the same times. Yet, little is known regarding the impacts of specific dietary support processes involved in maintaining said communal diet when one partner drastically alters his or her eating patterns. The current study defined dietary sacrifice as a phenomenon within the context of Celiac Disease (CD): a chronic illness that requires strict adherence to the gluten-free diet (GFD). Drawing from existing research on sacrifice within romantic relationships (e.g., Impett & Gordon, 2008), this project examined whether non-Celiac partners' adherence to the GFD during shared mealtimes impacted relationship satisfaction for both couple members. Female Celiacs and their non-Celiac cohabitating partners (N=152 couples) were recruited for an online survey through various support organizations. Given the dyadic design of this study, the Actor-Partner Interdependence Mediation Model (APIMeM; Ledermann, Macho, & Kenny, 2011) was used to examine the mediating influence of Dietary Approach and Avoidance Motives. Results indicated that partner support in the form of shared GFD adherence bolstered couple happiness to the extent that it was performed for positive gains (e.g., promoting health and well-being) by the non-Celiac. While dietary sacrifice was positively associated with Celiacs' relationship satisfaction above and beyond non-Celiacs' endorsement of Dietary Avoidance Motives, both dyad members experienced significantly lower relationship satisfaction when non-Celiac partners adhered to the diet to deflect negative outcomes (e.g., rejection, fighting). This study serves as the first application of relationship sacrifice research to a specific health issue, and the first psychological exploration into intimate partners' dietary support processes within the Celiac population.
118

Development of a Prolyl Endopeptidase Expression System in <i>Lactobacillus Reuteri</i> to Reduce the Clinical Manifestation of Celiac Disease

Jew, Kara Lynn 01 July 2019 (has links) (PDF)
Celiac Disease (CD) is an autoimmune disorder that emerges due to the ingestion of gluten, a protein found in a variety of common grains such as wheat, rye, and barley. Approximately 1 in 100 individuals in the US suffer from CD, making it the most commonly diagnosed gastrointestinal disorder (Ciclitira et. al., 2005). These proline-rich gluten peptides are resistant to proteolysis and accumulate in the duodenum of the small intestine. Once in the duodenum, these peptides illicit an autoimmune response resulting in villous atrophy. Current treatment for CD requires a rigorous adherence to a gluten-free diet. Nevertheless, gluten-containing grains are ubiquitous in the western diet, so accidental exposure to gluten remains as a persistent threat. The approach of this project centers on genetically engineering a strain Lactobacillus reuteri to secrete a Myxococcus xanthus prolyl endopeptidase (PEP), an enzyme that hydrolyzes a peptide bond adjacent to an internal proline residue. The data from this study revealed that recombinant M. xanthus PEP purified from E. coli was effective in degrading Suc-Ala-Pro-pNA, a chromogenic substrate containing an internal proline residue. When introduced into a L. reuteri expression vector, mutations accumulated in the vector over the course of 5 days. These data suggested that toxicity was possibly associated with M. xanthus PEP and the amyl signal peptide.
119

Mass screening for celiac disease in 12-year-olds : Finding them and then what?

Rosén, Anna January 2012 (has links)
Background Mass screening for celiac disease (CD) as a public health intervention is controversial. Before implementation, a suitable screening strategy should be outlined, and the acceptability of the screening scrutinized. Also, the benefits of early detection and possible negative consequences should be explored and compared. The overall aim of this thesis was to evaluate different strategies for finding 12-year-olds with undiagnosed CD in the general population, and to explore the experiences of those receiving the diagnosis in a mass screening. Methods A school-based CD screening of 12-year-olds was conducted in five study sites across Sweden. Out of 10041 children who were invited, 7208 had a blood sample analyzed for CD-marker tissue transglutaminase of isotype IgA (tTG-IgA) and 7161 for total serum IgA (s-IgA). If the s-IgA value was low, tTG-IgG was also measured. Additional analysis of endomysial antibodies (EMA) was performed if borderline values of tTG were found. In total, 192 had elevated CD-markers, 184 underwent a small intestinal biopsy and 153 eventually had CD diagnosed. Before receiving knowledge about their CD status, children and their parents filled in questionnaires regarding symptoms and CD-associated conditions. Questionnaires were returned by 7054 children (98%) and 6294 parents (88%). Later, all adolescents who had been diagnosed with CD more than one year ago (n=145), and their parents, were invited to a mixed-method follow-up study in which they shared their experiences in questionnaires, written narratives and focus group discussions. In total, we have information on 117 (81%) of these adolescents, either from the adolescents themselves (n=101) and/or from their parent/s (n=125). Data were analyzed using a combination of descriptive and analytical quantitative and qualitative methodologies. Results We found that information on symptoms and CD-associated conditions were poor predictors for finding undiagnosed CD in the study population. Questionnaire-based case-finding by asking for CD-associated symptoms and conditions would have identified 52 cases (38% of all cases) at a cost of blood-sampling 2282 children (37% of the study population). The tTG-IgA test had an excellent diagnostic accuracy with the area under the receiver operating characteristic curve of 0.988. If using the recommended cut-off for tTG-IgA (&gt;5 U/mL) 151 had fulfilled biopsy criteria and 134 CD cases had been identified. The strategy of lowering the cut-off to tTG-IgA&gt;4 U/mL, and adding the EMA analysis in those with tTG-IgA between 2-4 U/mL, identified another 17 cases (a 12% increase) at the cost of performing 32 additional biopsies. Measuring total s-IgA in 7161 children discovered only two additional cases at the cost of performing 5 additional biopsies. The positive predictive value of our screening strategy was 80%.  Results from the follow-up study of the screening-detected CD cases illustrated that 54% reported health improvement after initiated treatment, but also that these health benefits had to be balanced against social sacrifices. We also found that although the screening-detected diagnosis was met with surprise and anxiety, the adolescents and their parents were grateful for being made aware of the diagnosis. A majority of parents (92%) welcomed a future screening, but both adolescents and parents suggested that it should be conducted earlier in life. Conclusion Obtaining information on symptoms and CD-associated conditions was not a useful step in finding undiagnosed CD cases in a general population. The serological marker tTG-IgA, however, had excellent diagnostic accuracy also when lowering the cut-off. The diagnosis had varying impact on adolescents’ quality of life, and their perceived change in health had to be balanced against the social sacrifices resulting from the diagnosis. Overall, CD mass screening seemed acceptable to most of those who were diagnosed and their parents.
120

Une nouvelle stratégie de traitement de la maladie cœliaque basée sur les polymères séquestrants

Pinier, Maud 11 1900 (has links)
La maladie cœliaque ou sprue cœliaque est une intolérance au gluten. Il s’agit d’une maladie inflammatoire de l’intestin liée à l’ingestion de gluten chez des personnes génétiquement susceptibles. Ce désordre présente une forte prévalence puisqu’il touche 1 % de la population mondiale. En l’état actuel des choses, il n’existe aucun outil pharmacologique pour traiter ou pallier à cette maladie. Cependant, grâce aux avancées dans la compréhension de sa pathogenèse, de nouvelles cibles thérapeutiques ont été identifiées. À l’heure actuelle, le seul traitement efficace consiste à suspendre la consommation de l’agent pathogène, à savoir le gluten. Le gluten est un ensemble de protéines de stockage des céréales contenu dans le blé, l’orge et le seigle. Le gluten du blé se subdivise en gluténines et gliadines. Ce sont ces dernières qui semblent les plus impliquées dans la maladie cœliaque. Les gliadines et ses protéines apparentées (i.e. sécalines et hordéines, respectivement dans le seigle et l’orge) sont riches en prolines et en glutamines, les rendant résistantes à la dégradation par les enzymes digestives et celles de la bordure en brosse. Les peptides résultant de cette digestion incomplète peuvent induire des réponses immunitaires acquises et innées. L’objectif principal de cette thèse était de tester un nouveau traitement d’appoint de la maladie cœliaque utile lors de voyages ou d’évènements ponctuels. Dans les années 80, une observation italienne montra l’inhibition de certains effets induits par des gliadines digérées sur des cultures cellulaires grâce à la co-incubation en présence de mannane: un polyoside naturel composé de mannoses. Malheureusement, ce traitement n’était pas applicable in vivo à cause de la dégradation par les enzymes du tractus gastro-intestinales du polymère, de par sa nature osidique. Les polymères de synthèse, grâce à la diversité et au contrôle de leurs propriétés physico-chimiques, se révèlent être une alternative attrayante à ce polymère naturel. L’objectif de cette recherche était d’obtenir un polymère liant la gliadine, capable d’interférer dans la genèse de la maladie au niveau du tube digestif, afin d’abolir les effets délétères induits par la protéine. Tout d’abord, des copolymères de type poly (hydroxyéthylméthacrylate)-co-(styrène sulfonate) (P(HEMA-co-SS)) ont été synthétisés par polymérisation radicalaire contrôlée par transfert d’atome (ATRP). Une petite bibliothèque de polymères a été préparée en faisant varier la masse molaire, ainsi que les proportions de chacun des monomères. Ces polymères ont ensuite été testés quant à leur capacité de complexer la gliadine aux pH stomacal et intestinal et les meilleurs candidats ont été retenus pour des essais cellulaires. Les travaux ont permis de montrer que le copolymère P(HEMA-co-SS) (45:55 mol%, 40 kDa) permettait une séquestration sélective de la gliadine et qu’il abolissait les effets induits par la gliadine sur différents types cellulaires. De plus, ce composé interférait avec la digestion de la gliadine, suggérant une diminution de peptides immunogènes impliqués dans la maladie. Ce candidat a été testé in vivo, sur un modèle murin sensible au gluten, quant à son efficacité vis-à-vis de la gliadine pure et d’un mélange contenant du gluten avec d’autres composants alimentaires. Le P(HEMA-co-SS) a permis de diminuer les effets sur les paramètres de perméabilité et d’inflammation, ainsi que de moduler la réponse immunitaire engendrée par l’administration de gliadine et celle du gluten. Des études de toxicité et de biodistribution en administration aigüe et chronique ont été réalisées afin de démontrer que ce dernier était bien toléré et peu absorbé suite à son administration par la voie orale. Enfin des études sur des échantillons de tissus de patients souffrants de maladie cœliaque ont montré un bénéfice therapeutique du polymère. L’ensemble des travaux présentés dans cette thèse a permis de mettre en évidence le potentiel thérapeutique du P(HEMA-co-SS) pour prévenir les désordres reliés à l’ingestion de gluten, indiquant que ce type de polymère pourrait être exploité dans un avenir proche. / Celiac Disease or celiac sprue is identified as a gluten intolerance. It is an inflammatory disorder of the intestine triggered by the ingestion of gluten in genetically susceptible individuals. This condition is highly prevalent because it affects up to 1% of the worldwide population. Nowadays, there is no pharmacological treatment available to treat or off set to the disease. Due to the huge progress in the understanding of the pathogenesis, new therapeutic targets have been discovered. At the present time, the only effective treatment remains the strict lifelong abandonment of the pathogen agent, gluten. Gluten encompasses the storage proteins in wheat, rye and barley. The wheat gluten is divided into glutenins and gliadins. The latter seem to be the most important trigger in the celiac disease. Gliadins and the related proteins (i.e. secalins and hordeins, respectively in rye and barley) are rich in prolin and glutamin residues, conferring them to be resistant by enzymatic digestion. The resulting peptides of the incomplete process may set off the inflammatory reaction. The main objective of this thesis was to test a new supportive therapy in treating celiac disease, useful in punctual occasion (i.e. during travel or social event when the gluten-free property cannot be ascertained). In the 1980’s, inhibition of some gliadin-induced effects on cell cultures were observed owing to mannan co-incubation. However, this compound, due to his osidic nature, may be cleaved by digestive enzymes in vivo. Synthetic polymers prove to be an attracting alternative owing to the tunability of their physical and chemical properties. The goal of this study was to obtain a polymeric gliadin-binder, interferring with the pathogenesis of the celiac disease in the gastro-intestinal tract, to abrogate the gliadin induced effects. Atom transfer radical polymerization was used to synthesize copolymers of the type poly (hydroxyethylméthacrylate)-co-(styren sulfonate) (P(HEMA-co-SS)). A small library of polymers varying in their molecular weight and in their constituting monomers ratio was prepared. The ability of these polymers to sequester gliadin was assessed at stomacal and intestinal pH. The best candidates were further evaluated in cell cultures. Our results revealed that a selective binding was obtained with the P(HEMA-co-SS) (45:55 mol%, 40 kDa). This compound abolished gliadin-induced effects on various cell lines. In addition, gliadin digestion was hindered, suggesting a decrease in the formation of immunogenic peptides known to trigger the diseases. In vivo experiments were additionally carried out on a murine model of gluten-sensitivity with this polymeric candidate. Its efficacy towards pure gliadin and gluten containing food was tested. P(HEMA-co-SS decreased gliadin–induced effect on permeability and inflammatory parameters and modulated the immune response due to gliadin/gluten gavage. Toxicity and biodistribution studies following acute and chronic administration were performed on murine to demonstrate that the polymer was well tolerated and not absorbed after oral administration. Finally, biopsies of patients suffering from CD disease exhibited therapeutic benefit of the polymer. Altogether, the results presented in this thesis evidenced the potential of P(HEMA-co-SS) to prevent the gluten-induced disorder, indicating that this type of polymer may be useful in a near future.

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