Yes / Our aim is to provide an understanding of the experience of women with IBD who have made the transition to motherhood. Twenty-two mothers with IBD were recruited from around the UK. Semi-structured interviews were conducted and analyzed using thematic analysis. The central concept – Blurred Lines – offers a novel frame for understanding the transition to motherhood with IBD through identifying parallels between having IBD and becoming, and being, a mother. Parallels clustered into three main themes: Need for Readiness, Lifestyle Changes, and Monitoring Personal and Physical Development. Hence, women with IBD are in some ways well prepared for the challenges of motherhood even though, as a group, they tend to restrict their reproductive choices. We recommend health professionals initiate conversations about reproduction early and provide a multidisciplinary approach to pregnancy and IBD in which women have confidence that their on-going treatment will be integrated successfully with their maternity care. / Crohn’s & Colitis UK [grant number SP2013/2].

Ce travail présente les résultats de recherches sur le contrôle d'écoulement dans les liquides diélectriques. L'objectif est d'étudier les potentialités du contrôle d'écoulement au moyen d'actionneurs ElectroHydroDynamiques. La 1re partie de cette thèse est notamment consacrée à l'étude bibliographique générale du contrôle d'écoulement et des techniques disponibles pour la mesure de vitesse de fluide. La méthode PIV est choisie pour caractériser l'écoulement de panache chargé. Cependant la présence d'un champ électrique intense dans un liquide diélectrique remet potentiellement en question l'hypothèse selon laquelle les traceurs suivent fidèlement les mouvements du liquide. Des études théorique et expérimentale permettent de préciser les conditions d'un traceur idéal et de choisir le meilleur type d'ensemencement pour l'huile de silicone. La 2nde partie de ce travail est consacrée à l'étude du contrôle d'écoulement sur un profil d'aile NACA0015 à ultra-bas Reynolds (Re < 5000). Une étude bibliographique présente les stratégies de contrôle d'écoulement autour de profil d'aile ainsi que les types d'actionneurs EHD appliqués aux liquides diélectriques. L'écoulement naturel en champ de vitesse moyen puis instationnaire est caractérisé et comparé à l'écoulement contrôlé. Le calcul de la force à partir d'un bilan de quantité de mouvement (Navier-Stokes), permet d'estimer les efforts hydrodynamiques appliqués par le fluide sur le profil immergé. Des polaires de portance et de traînée sont obtenues et permettent de quantifier l'efficacité de l'actionneur EHD. Enfin, les mécanismes de contrôle sont précisés et mettent en lumière les potentiels et les limites de l'actionneur. / This work presents results of research on flow control in a dielectric liquid. The aim is to demonstrate our ability to control flow by means of ElectroHydroDynamic actuation. The first part of this PhD thesis is dedicated to a general overview of flow control and the methods available for measuring fluid velocity. The PIV method is selected to charaterize the flow of a charged plume. However, the presence of a high electric field in the dielectric liquid might bring into question the validity of using PIV, which is based on the fact that tracers accurately follow fluid movement. Theoretical and experimental studies were performed to find the proper conditions for using an ideal tracer that guarantees the accuracy of velocity measurements. This part enables us to choose the best seeding particle in silicone oil. The second part of this work is devoted to the study of flow control on a NACA0015 wing profile at ultra-low Reynolds numbers (Re < 5000). A bibliographic study presents strategies of flow control around wing profiles and in addition deals with different EHD actuators for dielectric liquids. Mean velocity fields and unsteady velocity fields of baseline flow are characterized and compared to controlled flow. The calculation of force based on the conservation of momentum (Navier-Stokes equations) enables us to estimate the hydrodynamic stresses applied by the fluid to the immersed profile. Lift and drag polarities are obtained to quantify the efficiency of the EHD actuator. Finally, the mechanisms of control are clarified and highlight the potential and limits of the EHD actuator for flow control applications.

The mammalian intestine harbors an estimated 100 trillion microorganisms, which normally maintain a mutually beneficial relationship with the host. The intestinal epithelium consists of a single layer of intestinal epithelial cells (IECs) that provides a physical barrier as well as innate immune defense, preventing this vast community of microbes from entering host tissues. Secretory immunoglobulin A (SIgA) acts as the first line of antigen-specific immunity at the interface between the gut microbiota and the intestinal epithelium. Polymeric IgA secreted by plasma cells in the intestinal lamina propria is transported across IECs by the polymeric immunoglobulin receptor (pIgR). Defects in epithelial barrier and immune functions can lead to infections with opportunistic and pathogenic microbes and contribute to the etiology of inflammatory bowel disease (IBD). Here we investigate the ability of IEC biomarkers to define the mechanism and severity of intestinal inflammation, as well as provide insight into the function of IEC in regulating intestinal homeostasis and inflammation. Importantly, down-regulation of pIgR expression was a common feature in human IBD and mouse models of experimental colitis. One molecule of pIgR is consumed for every molecule of SIgA transported, thus high expression of pIgR is required to maintain sufficient supply of SIgA. Accordingly, we investigate the mechanisms by which IECs regulate pIgR expression in response to colonic bacteria. Cross-talk between the microbiota and IECs is mediated by pattern recognition receptors, including Toll-like receptors (TLR), leading to expression of gene products that enhance epithelial barrier function and innate immunity. The cytoplasmic adaptor protein MyD88 transduces signals from TLRs that recognize bacterial products. We show that pIgR induction by colonic bacteria is dependent on TLR4-MyD88 activation of NF-κB signaling. We examined the role of epithelial-specific MyD88 signaling in antibacterial immunity and epithelial expression of key gene products that participate in innate immunity in the gut by generating mice with an IEC-targeted deletion of the Myd88 gene (MyD88ΔIEC). MyD88ΔIEC mice display immunological and antimicrobial defects resulting in increased susceptibility to experimental colitis. We conclude that cross-talk between bacteria and IECs via MyD88-dependent signaling is crucial for maintenance of gut homeostasis.

Inflammatory bowel diseases (IBD) are an autoimmune illnesses affecting gastrointestinal tract. The main types include ulcerative colitis and Crohn's disease. Recently, primary sclerosing cholangitis (PSC) has also been associated with IBD. PSC is a chronic liver disease associated with bile duct stenosis. The exact pathogenesis and etiology of these diseases is not clear, despite the great efforts of the scientific community. They are multifactorial diseases that are associated with dysbiosis of intestinal microbiota. Their diagnosis is based on for patients unpleasant endoscopic examinations and therefore the search for new serum biomarkers is needed and appreciated target of scientific interest. In the first part of diploma thesis, we focused on the reactivity of peripheral blood cells of IBD patients to 10 selected representatives of typical intestinal microbiota: Lactobacillus plantarum, Bifidobacterium adolescentis, Blautia coccoides, Roseburia intestinalis, Eubacterium rectale, Faecalibacterium prausnitzii, Ruminococcus flavefaciens, Bacteroides thetaiotaomicron, Prevotella ruminicola and Escherichia coli. Reactivity of CD, UC and PSC- IBD patients was increased after stimulation with Faecalibacterium, Lactobacillus and Prevotella. However, we got low percentage of cytokine-producing cells,...

Initiation and perpetuation of inflammatory bowel diseases (IBD) may result from an exaggerated mucosal immune response to the luminal microbiota in a susceptible host. We proposed that this may be caused either 1) by an abnormal microbial composition or 2) by weakening of the protective mucus layer due to excessive mucus degradation, which may lead to an easy access of luminal antigens to the host mucosa triggering inflammation. We tested whether the probiotic Enterococcus faecium NCIMB 10415 (NCIMB) is capable of reducing chronic gut inflammation by changing the existing gut microbiota composition and aimed to identify mechanisms that are involved in possible beneficial effects of the probiotic. To identify health-promoting mechanisms of the strain, we used interleukin (IL)-10 deficient mice that spontaneously develop gut inflammation and fed these mice a diet containing NCIMB (106 cells g-1) for 3, 8 and 24 weeks, respectively. Control mice were fed an identically composed diet but without the probiotic strain. No clear-cut differences between the animals were observed in pro-inflammatory cytokine gene expression and in intestinal microbiota composition after probiotic supplementation. However, we observed a low abundance of the mucin-degrading bacterium Akkermansia muciniphila in the mice that were fed NCIMB for 8 weeks. These low cell numbers were associated with significantly lower interferon gamma (IFN-γ) and IFN-γ-inducible protein (IP-10) mRNA levels as compared to the NCIMB-treated mice that were killed after 3 and 24 weeks of intervention. In conclusion, NCIMB was not capable of reducing gut inflammation in the IL-10-/- mouse model. To further identify the exact role of A. muciniphila and uncover a possible interaction between this bacterium, NCIMB and the host in relation to inflammation, we performed in vitro studies using HT-29 colon cancer cells. The HT-29 cells were treated with bacterial conditioned media obtained by growing either A. muciniphila (AM-CM) or NCIMB (NCIMB-CM) or both together (COMB-CM) in Dulbecco’s Modified Eagle Medium (DMEM) for 2 h at 37 °C followed by bacterial cell removal. HT-29 cells treated with COMB-CM displayed reduced cell viability after 18 h (p<0.01) and no viable cells were detected after 24 h of treatment, in contrast to the other groups or heated COMB-CM. Detection of activated caspase-3 in COMB-CM treated groups indicated that death of the HT-29 cells was brought about by apoptosis. It was concluded that either NCIMB or A. muciniphila produce a soluble and heat-sensitive factor during their concomitant presence that influences cell viability in an in vitro system. We currently hypothesize that this factor is a protein, which has not yet been identified. Based on the potential effect of A. muciniphila on inflammation (in vivo) and cell-viability (in vitro) in the presence of NCIMB, we investigated how the presence of A. muciniphila affects the severity of an intestinal Salmonella enterica Typhimurium (STm)-induced gut inflammation using gnotobiotic C3H mice with a background microbiota of eight bacterial species (SIHUMI, referred to as simplified human intestinal microbiota). Presence of A. muciniphila in STm-infected SIHUMI (SIHUMI-AS) mice caused significantly increased histopathology scores and elevated mRNA levels of IFN-γ, IP-10, tumor necrosis factor alpha (TNF-α), IL-12, IL-17 and IL-6 in cecal and colonic tissue. The number of mucin filled goblet cells was 2- to 3- fold lower in cecal tissue of SIHUMI-AS mice compared to SIHUMI mice associated with STm (SIHUMI-S) or A. muciniphila (SIHUMI-A) or SIHUMI mice. Reduced goblet cell numbers significantly correlated with increased IFN-γ (r2 = -0.86, ***P<0.001) in all infected mice. In addition, loss of cecal mucin sulphation was observed in SIHUMI-AS mice. Concomitant presence of A. muciniphila and STm resulted in a drastic change in microbiota composition of the SIHUMI consortium. The proportion of Bacteroides thetaiotaomicron in SIHUMI, SIHUMI-A and SIHUMI-S mice made up to 80-90% but was completely taken over by STm in SIHUMI-AS mice contributing 94% to total bacteria. These results suggest that A. muciniphila exacerbates STm-induced intestinal inflammation by its ability to disturb host mucus homeostasis. In conclusion, abnormal microbiota composition together with excessive mucus degradation contributes to severe intestinal inflammation in a susceptible host. / Die Initiation and die Manifestation von entzündlichen Darmerkrankungen (inflammatory bowel diseases - IBD) können aus einer übersteigerten mukosalen Immunreaktion auf die luminale Mikrobiota in einem empfänglichen Wirt resultieren. Wir schlagen vor, dass dies entweder durch 1) eine abnormale mikrobielle Zusammensetzung oder 2) die Abschwächung der schützenden Schleimschicht, eingeleitet durch deren fortgeschrittenen Abbau, verursacht werden kann. Diese Entwicklung ermöglicht einen erleichterten Zugang des luminalen Antigens zu der Mukosa des Wirts und somit die Auslösung der Entzündung. Wir haben getestet, ob das probiotische Bakterium Enterococcus faecium NCIMB 10415 (NCIMB) in der Lage ist, der chronischen Darmentzündung durch Veränderung der Zusammensetzung der Darmmikrobiota entgegenzuwirken und strebten an, die zugrunde liegenden Mechanismen der probiotischen Wirkungsweise zu identifizieren. Für die Aufklärung der gesundheitsfördernden Mechanismen dieses Bakterienstammes wurden Interleukin-10 defiziente Mäuse verwendet, die spontan eine Darmentzündung entwickeln. Den Mäusen wurde für 3, 8 und 24 Wochen eine NCIMB enthaltende Diät verabreicht. Nach der Fütterung waren keine eindeutigen Unterschiede zwischen den Gruppen hinsichtlich der Genexpression von pro-inflammatorischen Zytokinen und der Zusammensetzung der Darmmikrobiota zu beobachten, obwohl eine geringere Zellzahl des schleimabbauenden Bakteriums Akkermansia muciniphila in den mit NCIMB gefütterten Mäusen nach 8 Wochen festgestellt wurde. Daraus folgt, dass NCIMB nicht in der Lage ist, dem Verlauf der Darmentzündung im IL-10-/--Mausmodell entgegenzuwirken. In der nachfolgenden Studie wurde untersucht, wie die Anwesenheit von A. muciniphila den Ausprägungsgrad einer intestinalen Salmonella enterica Typhimurium (STm) induzierten Darmentzündung beeinflusst. Dafür wurden gnobiotische C3H-Mäuse mit einem mikrobiellen Hintergrund von acht Bakterienspezies (SIHUMI) verwendet. Die gleichzeitige Anwesenheit von A. muciniphila und STm verursachte eine drastische Veränderung der Mikrobiota-Zusammensetzung des SIHUMI-Konsortiums. Diese Ergebnisse zeigen, dass A. muciniphila durch seine Fähigkeit, die Homöostase/Selbstregulation der Schleimbildung zu stören, die STm-induzierte Darmentzündung verschärft. Es kann geschlußfolgert werden, dass eine abweichende Zusammensetzung der Mikrobiota in Kombination mit einem massiven Abbau des Mucus zur schweren intestinalen Entzündung im empfänglichen Wirt beiträgt.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Background: Exacerbated or prolonged inflammatory responses can be detrimental to the host, then any antiinflammatory mediators act to regulate the properties of pro-inflammatory factors and ensure the homeostasis of the organic systems. Objectives: Aims: This study has focused in the regulation of expression and the immunomodulatory properties of annexin A1, a protein of 37 KDa, originally known as the second messenger action of glucocorticoids, in inflammatory and infectious processes. Methods: Using molecular (qPCR), biochemical (luminometry) and immunological (flow cytometry, immunofluorescence) tools, we investigated the endogenous and exogenous of ANXA1 and its mimetic peptide (Ac2-26) in different conditions in vitro and in vivo: fungi infection, HIV/SIV infecion, bowel inflammatory disease and renal ischemic injury. Results: The Ac2-26 pre-treatment of PMN and PBMC of human peripheral blood stimulated with opsonized-zymosan inhibited the production of reactive oxygen species in a dose-dependent manner. In parallel, incubation of phagocytes with the peptide was shown to decrease expression of TLR2 receptor, responsible for the recognition of zymosan on phagocyte, suggesting a regulatory mechanism of surface receptor by ANXA1 peptide. Due to last data, the expression of CCR5, chemokine receptor and HIV co-receptor, was investigated in the same in vitro conditions. CCR5 transcription was down-regulated in PBMC from HIV-infected and healthy subjects, partially by ANXA1/FPR pathway. Consistently, both PBMC subject groups showed an impairment of percentage of CCR5+CD4+ T cells after Ac2-26 incubation. In contrast, Ac2-26 showed an up-regulation of CCR5 surface expression in monocytes, however the peptide switched the profile of monocyte subsets, increasing CD14highCD16- and decreasing CD14lowCD16+ populations. The last one is the most susceptible to HIV infection. In conclusion, the data suggest that the action of N-terminal ANXA1 is cell-dependent and may contribute indirectly modulating the HIV-1. Coherently, the study in vivo of ANXA1 expression in a non-human model of AIDS, showed that ANXA1 is regulated during the progression of the disease in the main compartments of infection, the blood and the gut. In comparison with samples of uninfected animals, the ANXA1 transcripts in peripheral blood increased from acute to chronic SIV infection, whereas in the intestinal mucosa it was down-regulated, reaching baseline levels only in chronic infection. Analysis of typical markers of AIDS progression, showed that increased ANXA1 transcripts was significantly correlated with the activation of T cells. However, the expression of ANXA1 had a positive correlation with antiinflammatory cytokines in the blood and in the intestine and a inverse dynamics of viral load and depletion of CD4 T cells, suggesting that activation of its transcription is related to an attempt to reduce the immune depletion during infection. In addition, based on the described differential modulation of the ANXA1 in the gut of primates, another goal was to analyze the expression of ANXA1 in patients with IBD (inflammatory bowel disease) or not treated with immunosuppressive drugs. The correlation among those factors and clinical data were analyzed. In IBD patients, the expression of ANXA1 is reduced in level of mRNA in peripheral blood and protein in the colonic mucosa. In these patients, immunotherapy with infliximab (anti-TNF-alpha) modulates the transcription of ANXA1 and TNF-&#945;, and even systemic lymphocyte activation in accordance with the duration of treatment and the side effects of drugs, such as bacteremia. The dynamics of ANXA1 added to other clinical and immunological factors appear to be associated with the course of IBD. Finally, acute and chronic inflammatory process induced by ischemia/reperfusion (I/R) procedure, revealed that exogenous ANXA1 mimetic peptide granted a remarkable protection against kidney I/R injury, preventing glomerular filtration rate and urinary osmolality decreases and acute tubular necrosis development by affording striking structural protection due to the abortion of neutrophil extravasation, attenuation of macrophage infiltration and regulation of endogenous annexin A1 expression in renal epithelial cells. Conclusions: In a general analysis of all studies presented, we conclude that exogenous ANXA1 and its derived peptides act as key molecules in the modulation of specific activation, immunophenotype and distribution of phagocytes and lymphocytes participating as a line of defense or targeting of infectious agents, via FPRs or not. And, emphasizing the importance of ANXA1 in the defense of homeostasis, although it was found that the pathways related to the regulation of endogenous ANXA1 is differentially activated in tissues and fluids under acute and chronic inflammation caused by viral infection, autoimmunity or hypoxia. / Introdução: As respostas inflamatórias exacerbadas ou prolongadas podem ser prejudiciais para o hospedeiro, então muitos mediadores antiinflamatórios atuam para regular as propriedades dos fatores pró-inflamatórios e garantir a homeostasia dos sistemas. Objetivos: Assim, o foco do presente trabalho foi estudar a regulação da expressão e as propriedades imunomodulatórias da anexina A1, uma proteína de 37 KDa, inicialmente conhecida como a segunda mensageira da ação dos glicocorticóides, em processos inflamatórios e infecciosos. Metodologia: Para tanto, por meio de técnicas moleculares (qPCR), bioquímicas (luminometria) e imunológicas (citometria de fluxo, imunofluorescência), foi investigado o papel endógeno da ANXA1 e exógeno do peptídeo N-terminal da ANXA1 em diferentes condições in vitro e in vivo: infecção fúngica, infecção viral por HIV-1 e SIV, doença inflamatória intestinal e injúria isquêmica renal. Resultados: O peptídeo N-terminal da ANXA1, Ac2-26, quando usado como tratamento prévio de PMN e PBMC do sangue periférico humano estimuladas por zymosan-opsonizado, inibe a produção de espécies reativas de oxigênio de modo dose-dependente. Paralelamente, a incubação dos fagócitos com o peptídeo demonstrou diminuir a expressão do receptor TLR2, responsável pelo reconhecimento de zymosan nos fagócitos, sugerindo um mecanismo de regulação de receptores de superfície pelo Ac2-26. Frente a este dado e a sinalização de ANXA1 via FPRs, a expressão do receptor de quimiocina e coreceptor do vírus HIV-1, CCR5, também foi investigada em tais condições in vitro. Os transcritos de CCR5 diminuíram em PBMCs de indivíduos HIV+ e saudáveis, parcialmente pela via ANXA1/FPR. Consistentemente, Ac2-26 também diminuiu a expressão do CCR5 na superfície de células T CD4+, os principais alvos do vírus. Em contraste, nos monócitos o peptídeo aumentou a expressão de CCR5, no entanto, induziu uma mudança na distribuição dos subfenótipos, diminuindo a quantidade dos monócitos com maior susceptibilidade a infecção por HIV-1 (CD14lowCD16+). A investigação da ANXA1 endógena em um modelo não humano de AIDS, realizado pela infecção de macacos por SIV, mostrou que a expressão transcricional da ANXA1 é regulada durante a progressão da doença nos principais compartimentos de infecção, o sangue e o intestino. Em comparação com as amostras de animais não-infectados, os transcritos de ANXA1 aumentaram gradualmente no sangue periférico entre as fases aguda e crônica da infecção por SIV, enquanto que na mucosa intestinal houve uma regulação negativa, atingindo os níveis basais apenas na infecção crônica. A análise de marcadores típicos da progressão da AIDS mostrou que a expressão de ANXA1 está relacionada à ativação de células T. No entanto, a expressão da ANXA1 tem uma correlação positiva com o número de transcritos de citocinas antiinflamatórias e uma correlação negativa com a carga viral e depleção de células T CD4+ no sangue e no intestino, sugerindo que a ativação da sua transcrição está relacionada a tentativa de diminuir a exaustão imunológica durante a infecção. Frente aos dados da modulação diferencial da ANXA1 no intestino de primatas, o próximo objetivo foi analisar a expressão da ANXA1 nos portadores de IBD (doença inflamatória intestinal) tratados ou não com drogas imunossupressoras. Nos indivíduos com IBD, a expressão da ANXA1 é diminuída em nível de RNAm, no sangue periférico, e proteína, na mucosa colônica. Nestes pacientes, a imunoterapia com infliximab (anti-TNF-&#945;) modulou sistemicamente a transcrição da ANXA1 e do TNF-&#945;, e ainda a ativação linfocitária e a bacteremia. Em suma, a dinâmica da ANXA1 somada a outros elementos imunológicos e clínicos parecem estar associados a progressão do curso das IBDs. Finalmente, os processos inflamatórios agudo e crônico induzidos pelo procedimento de isquemia e reperfusão (I/R) revelou que o peptídeo mimético ANXA1 exógeno protegeu significativamente contra a lesão por I/R renal. Os animais pré-tratados com Ac2-26 mostraram menores taxas de filtração glomerular, osmolalidade urinária e desenvolvimento da necrose tubular aguda, possivelmente, por manter a integridade tecidual devido ao bloqueio total do extravasamento de neutrófilos, à atenuação de infiltração de macrófagos e à regulação da expressão protéica da ANXA1 endógena em células epiteliais renais. Estes resultados apontam um importante papel da ANXA1 na defesa das células epiteliais contra a lesão de I/R e indicam que os neutrófilos são mediadores-chave para o desenvolvimento da lesão do tecido renal após I/R. Conclusões: Em uma análise geral do conjunto de estudos apresentados, é possível concluir que a ANXA1 exógena e seus peptídeos derivados atuam como moléculas chave na modulação específica da ativação, imunofenótipo e distribuição dos fagócitos e linfócitos que participam como linha de defesa ou como alvo de agentes infecciosos, por meio da ligação com os FPRs ou por uma via ainda não elucidada. E, enfatizando a relevância da ANXA1 na defesa da homeostasia, ainda foi constatado que as vias relacionadas à regulação da ANXA1 endógena são ativadas diferencialmente em tecidos e fluidos sob inflamação aguda e crônica iniciadas quer seja por infecção viral, autoimunidade ou hipóxia. / Doutor em Genética e Bioquímica

Inflammatory bowel disease (IBD), which includes the subtypes Crohn's disease (CD) and ulcerative colitis (UC), is a common disease particularly in the Western world. IBD is characterised by inflammation of the small intestine and/or colon. The two subtypes affect different gut locations but both show an increased intestinal permeability or the 'leaky gut syndrome'. This led to the hypothesis that tight junction (TJ) proteins expressed in the epithelium may affect the intestinal permeability as a cause or effect of IBD.Initially, variants in the CARD15, IL23R and ATG16L1 genes, previously associated with an increased risk of IBD, were genotyped in a cohort of 500 IBD (295 CD and 205 UC) patients and 877 matched controls. These variants were significantly associated in our cohort. A random effects meta-analysis was undertaken on all previously reported CD associations with the variant rs2241880 from ATG16L1 (n=25, p=0.0017, OR: 1.36 95% CI 1.12-1.66) and with rs11209026 from IL23R (n=26, p=0.0006, OR: 0.37 95% CI 0.21-0.67), showing pooled odds ratios consistent with those reported in our cohort. Individuals carrying >1 CARD15 mutant variant were found to have a 2.5 fold increased risk of CD (p=0.0001). Candidate TJ proteins were chosen on the basis of previous reported associations and through the investigation of the claudin proteins which are abundant at TJs. Twenty one candidate genes were selected and 79 variants successfully genotyped in up to 1063 IBD (502 CD and 478 UC) and 870 control patients. Significant associations were detected with variants in the CLDN1, CLDN5 and CDH1 genes with CD; CLDN5, CLDN8 and CDH1 variants were associated to IBD; and the rs7791132 variant (between CLDN4 and ELN) and a CDH1 variant were associated to UC. The CLDN1 rs6809685 variant trended towards association in a Toronto ascertained IBD replication cohort (genotypic p=0.04, allelic p=0.06) suggesting this may be a novel IBD susceptibility variant. Small intestinal biopsies from CD patients with known rs6809685 genotypes showed a dose dependent reduced immunohistochemical staining of claudin 1 with carriage of the mutant G allele. Claudin 1 helps seal TJs and reduced levels may increase risk of CD.Peroxisome proliferator activator receptors (PPARs) can directly affect TJ proteins and could therefore affect intestinal permeability. Twelve PPARγ variants were genotyped in up to 1050 IBD (502 CD and 467 UC) and 725 control patients. Significant genotypic associations were found with the rs2067819 variant in CD (p=0.05) and IBD (p=0.02), and also the rs13099634 variant in UC (P=0.02). There was a strong gender difference particularly for rs2067819 and rs4135247, where allelic associations were highly significant and increased risk of IBD in men (p=0.01 and p=0.007 respectively). However no significant associations were found in the female cohort. Troglitazone a PPARα agonist increased Caco2 cell transepithelial electrical resistance (TEER), a marker of TJ integrity, and increased expression of claudins -3 and -4. In contrast, the PPARα antagonist GW6471 reduced the TEER without causing cell death and PPARγ ligands did not affect TEER measurements. In summary, using a robust cohort of cases and controls the data indicates that variants in genes encoding TJ proteins may affect susceptibility to IBD and that PPARs can regulate these proteins altering intestinal permeability.

The presented thesis discusses the issues of chronic inflammatory diseases of the digestive system and suggests the possibility of the alternative natural remedies improving the health conditions or prolonging the remission phase of IBD. The main goal is to design a probiotic supplement enriched by natural anti-inflammatory agents. Phytochemicals, concretely phenolic compounds, flavonoids, and carotenoids suppress harmful inflammatory processes by direct targeting the function of the immune cells or by inhibiting damaging oxidative stress in general. Therefore, there were several plants potentially rich for these biologically active substances selected. Concretely, blueberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), turmeric (Curcuma longa), peppermint (Mentha piperita), chamomile (Matricaria recutita), cinnamon (Cinnamomum zeylanicum), ginger (Zingiber officinale) and flax (Linum usitatissimum). The suitable parts of these plants were extracted by using a total of three different solvents – water, ethanol, and hexane for obtaining lipidic extracts. The concentration of total polyphenols, total flavonoids, total carotenoids, and the ascertainment of specific polyphenols was determined in the prepared extracts. These characteristics were enhanced by the measurement of antioxidant activity of the aqueous and ethanolic extracts. The interaction of individual samples with probiotic cultures (Bifidobacterium breve, Lactobacillus acidophilus) and the ability of extracts to influence the viability of probiotics in the model digestion process has been examined. The most interesting samples (aqueous extracts of blueberries, mint, chamomile, and cinnamon) were selected for further experiments. The possible cytotoxicity towards human intestinal epithelial cells was tested in vitro by the MTT tests utilizing the CaCo-2 cell line. Extracts showing the highest levels of beneficial phytochemicals and antioxidant activity, supporting the growth of probiotic cultures, and showing minimal cytotoxic effects on human intestinal cells were then co-encapsulated with probiotics into alginate particles of a diameter of 1 mm. Water extracts of mint, chamomile, and cinnamon have been chosen. The encapsulation efficiency of successfully entrapped probiotics and phenolic compounds was determined in prepared particles. Furthermore, the particles were studied during the process of model digestion, when the release of the desired substances in the various parts of the digestive system was observed and assessed whether the components would reach the crucial point of action – the colon. For the use of the proposed probiotic mixture as a dietary supplement, a recommended dose of 1 g has been determined. Lastly, possible adjustments such as lyophilization or sheathing by an extra protective polymerous layer, e.g. chitosan, were suggested to prolong the shelf life of the particles and volatile substances stability.

Bakgrund: Inflammatoriska tarmsjukdomar (IBD) är ett samlingsnamn för Crohns sjukdom och ulcerös kolit. Sjukdomarna är kroniska och kännetecknas av symtom som kommer i skov. Både Crohns sjukdom och ulcerös kolit har ökat i världen. Trotts det stigande antalet av sjukdomsfall i världen är kunskapen om IBD förhållandevis låg. Det är viktigt att upplevelserna av att leva med IBD lyfts fram, för att kunna möjliggöra en god personcentrerad omvårdnad. Syfte: Syftet var att beskriva upplevelser av att leva med en inflammatorisk tarmsjukdom (IBD) i det dagliga livet. Metod: En allmän litteraturstudie baserat på tio kvalitativa artiklar. Informationssökningen skedde i tre olika databaser: Cinahl, PudMed samt Psycinfo. Artiklarna granskades enligt Röda Korsets granskningsmall (2005). En innehållsanalys med deduktiv ansats utefter Patersons (2001) perspektivmodell med inspiration av Graneheim och Lundman (2004) gjordes. Resultat: Två innehållsområden och tio underkategorier framkom i resultatet: Upplevelser när sjukdomen bestämmer i det vardagliga livet: maten som fiende, trötthet som en ständig följeslagare, mediciner som stjälper istället för hjälper, en osynlig sjukdom som lätt leder till missförstånd, en vacklande framtidstro, att tvingas försaka och Upplevelser när välbefinnandet får styra i det vardagliga livet: maten som medicin, strävan efter kontroll, hopp och stöd i den kroniska sjukdomen, att se ny möjligheter. Diskussion: Metoddiskussionen skrevs utifrån Shentons (2004) trovärdighetsbegrepp. Resultatdiskussionen diskuterades utifrån tre fynd med hjälp av Paterson (2001) perspektivmodell och etiska begrepp samt ur ett samhällsperspektiv. De tre fynden är: Bristande förståelse, Begränsningar i det vardagliga livet samt Utveckling av färdigheter och förmågor efter satt diagnos.

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