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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.
311

Clinical and Experimental Studies on Inflammatory Bowel Disease with special emphasis on Collagenous Colitis

Wagner, Michael January 2010 (has links)
This thesis describes studies in patients with inflammatory bowel disease (IBD) and collagenous colitis (CC). We investigated mucosal eosinophil and neutrophil granulocytes and T-cells involved in the inflammatory processes and aimed at determining whether these processes are reflected in the faecal (F) contents of specific proteins secreted by cells in the intestinal mucosa. Thus, we measured eosinophil cationic protein (ECP) and eosinophil protein X (EPX) and the neutrophil derived myeloperoxidase (MPO) and calprotectin (C); and in addition, chromogranin A (CgA), Chromogranin B (CgB) and secretoneurin (SN), derived from EEC cells and cells in the enteric nervous system. We found that a normalised FC level can serve as a surrogate marker for successful treatment in patients with IBD, but persistently high FC levels need further evaluation (study I). Furthermore, FC and F-MPO appear to relate better than F-EPX to treatment outcome in IBD. We evaluated F-ECP, F-EPX, F-MPO and FC as markers of disease activity and treatment outcome in patients with CC (study III) and concluded that F-ECP was the best discriminator of detecting active CC. Normalised F-ECP and F-EPX could serve as markers of successful treatment. We showed that the inflammation in CC is characterised by activated eosinophils, but that there is no neutrophil activity (study II). T-cells have a lower grade of activity in active CC than in control subjects. During budesonide treatment the normal activation of eosinophils and T-cells is restored, with concomitant clinical remission. The findings in studies II and III indicate that the eosinophils have an essential role in the pathophysiology of CC. Markedly higher values of F-CgA, F-CgB and F-SN were found in patients with CC than in those with IBD and controls (study IV) indicating a crucial role for the intestinal neuro-endocrine system in the pathogenesis of collagenous colitis.
312

Epidemiologie chronisch entzündlicher Darmerkrankungen bei Kindern und Jugendlichen in Sachsen sowie jungen Erwachsenen in Leipzig

Zurek, Marlen 13 June 2013 (has links) (PDF)
Hintergrund: Angaben zu Inzidenz und Prävalenz von chronisch entzündlichen Darmerkrankungen (CED) bei Kindern und Jugendlichen in Deutschland fehlen bisher, die Daten des im Jahr 2000 gegründeten Sächsischen CED-Registers für Kinder und Jugendliche wurden bisher nicht veröffentlicht. Bei internen Diskussionen der Registerdaten zeigte sich stets eine nicht erklärbare abfallende altersspezifische Inzidenz der CED ab dem 15. Lebensjahr. Es wurde vermutet, dass einige ältere Jugendliche ausschließlich von Erwachsenengastroenterologen betreut wurden und bei einigen Adoleszenten eine längere diagnostische Latenz zur Diagnosestellung nach dem 18. Lebensjahr führte. Patienten und Methoden: Zur Prüfung der Thesen wurden alle gastroenterologisch tätigen Internisten in Leipzig aufgesucht und Patienten eingeschlossen, bei denen bis zum 26. Lebensjahr in den Jahren 2005-2009 eine CED endoskopisch neu diagnostiziert wurde. Die Auswertung des Sächsischen CED-Registers erfolgte hinsichtlich Inzidenz, Prävalenz, Geschlechterverteilung und diagnostischer Latenz im Zehnjahreszeitraum 2000-2009. Ergebnisse: Es wurden tatsächlich einige Jugendliche vor dem 18. Lebensjahr ausschließlich von Internisten betreut und nicht an das Register gemeldet. Die korrigierte Inzidenz von CED bei Patienten bis zum 18. Lebensjahr in Leipzig lag um 37 % höher als im Register angegeben. Nach dem 15. Lebensjahr wurde – ebenfalls in Abweichung zu den Registerdaten – ein kontinuierlicher Anstieg der altersspezifischen Inzidenz bis zum 18. Lebensjahr registriert. Es zeigte sich eine Tendenz zur längeren diagnostischen Latenz bei Adoleszenten, die sich jedoch nicht statistisch sichern ließ. Bis zum 15. Lebensjahr wurden nahezu alle Patienten im CED-Register erfasst.
313

The Ontario Crohn’s and Colitis Cohort: Incidence and Outcomes of Childhood-onset Inflammatory Bowel Disease in Ontario, Canada

Benchimol, Eric Ian 15 September 2011 (has links)
Inflammatory bowel disease (IBD), characterized by chronic gastrointestinal inflammation, represents a significant childhood chronic disease. In this thesis, a case ascertainment definition of paediatric-onset IBD was validated using administrative data and developed the Ontario Crohn’s and Colitis Cohort (OCCC). The epidemiology of paediatric IBD in Ontario was described, demonstrating that Ontario has one of the highest worldwide incidence rates. Statistically significant increases in incidence were noted in 0-4 year olds (5.0%/year, p=0.03) and 5-9 year olds (7.6%/year, p<0.0001), but not in other age groups. Lower income children were more likely to be hospitalized at least once (hazard ratio (HR) 1.17, 95% confidence intervals (CI) 1.05-1.30) or visit the ED (HR 1.21, 95% CI 1.09-1.35) and had more IBD-related physician visits (odds ratio (OR) 3.73, 95% CI 1.05-13.27). Lower income children with Crohn's disease (CD) (not ulcerative colitis [UC]) were more likely to undergo intra-abdominal surgery within 3 years of diagnosis (OR 1.22, 95% CI 1.01-1.49), especially if diagnosed after 2000 (OR 1.79, 95% CI 1.27-2.53). Finally, changes in health services utilization and surgical rates were described, as were changes in specialist care provision and immunomodulator use in children with IBD between 1994-2007. The changes to care included increased outpatient care provided by paediatric gastroenterologists, and increased immunomodulator use. Children diagnosed with CD, but not UC, in recent years had lower surgical rates. In CD patients, intra-abdominal surgical rates within three years of diagnosis decreased from 18.8% in children diagnosed in 1994-1997 to 13.6% in those diagnosed in 2001-2004 (P = 0.035). When stratified by age at diagnosis, this decrease was significant in children diagnosed ≥10 years old (OR 0.67, 95% CI 0.48-0.93). The OCCC will continue to be used to investigate the epidemiology and burden of paediatric IBD and to improve the care received by children with IBD in Ontario.
314

The Ontario Crohn’s and Colitis Cohort: Incidence and Outcomes of Childhood-onset Inflammatory Bowel Disease in Ontario, Canada

Benchimol, Eric Ian 15 September 2011 (has links)
Inflammatory bowel disease (IBD), characterized by chronic gastrointestinal inflammation, represents a significant childhood chronic disease. In this thesis, a case ascertainment definition of paediatric-onset IBD was validated using administrative data and developed the Ontario Crohn’s and Colitis Cohort (OCCC). The epidemiology of paediatric IBD in Ontario was described, demonstrating that Ontario has one of the highest worldwide incidence rates. Statistically significant increases in incidence were noted in 0-4 year olds (5.0%/year, p=0.03) and 5-9 year olds (7.6%/year, p<0.0001), but not in other age groups. Lower income children were more likely to be hospitalized at least once (hazard ratio (HR) 1.17, 95% confidence intervals (CI) 1.05-1.30) or visit the ED (HR 1.21, 95% CI 1.09-1.35) and had more IBD-related physician visits (odds ratio (OR) 3.73, 95% CI 1.05-13.27). Lower income children with Crohn's disease (CD) (not ulcerative colitis [UC]) were more likely to undergo intra-abdominal surgery within 3 years of diagnosis (OR 1.22, 95% CI 1.01-1.49), especially if diagnosed after 2000 (OR 1.79, 95% CI 1.27-2.53). Finally, changes in health services utilization and surgical rates were described, as were changes in specialist care provision and immunomodulator use in children with IBD between 1994-2007. The changes to care included increased outpatient care provided by paediatric gastroenterologists, and increased immunomodulator use. Children diagnosed with CD, but not UC, in recent years had lower surgical rates. In CD patients, intra-abdominal surgical rates within three years of diagnosis decreased from 18.8% in children diagnosed in 1994-1997 to 13.6% in those diagnosed in 2001-2004 (P = 0.035). When stratified by age at diagnosis, this decrease was significant in children diagnosed ≥10 years old (OR 0.67, 95% CI 0.48-0.93). The OCCC will continue to be used to investigate the epidemiology and burden of paediatric IBD and to improve the care received by children with IBD in Ontario.
315

Sjukdomsrelaterad oro hos personer med Crohns sjukdom- en intervjustudie / Disease-related worries in persons with Crohn´s disease - an interview study

Wåhlin, Monica January 2015 (has links)
Bakgrund: En kronisk oförutsägbar sjukdom som Crohns sjukdom framkallar fysisk, psykologisk och social stress. Sjukdomen påverkar vardagen, försämrar livskvalitet och skapar oro. För att bedriva personcentrerad vård krävs insikt i hur denna oro upplevs. Syfte: Syftet med studien var att belysa sjukdomsrelaterad oro hos personer med Crohns sjukdom. Metod: Åtta kvinnor och fyra män mellan 30 och 64 år som skattat sin sjukdomsrelaterade oro som hög eller mycket hög identifierades. Intervjuer genomfördes och analyserades med kvalitativ innehållsanalys. Resultat: Analysen genererade tre kategorier: (1) Oro för sjukdomen i sig, (2) känslor runt oron, (3) samt hantering av oron. Sjukdomens oförutsägbarhet samt nedsatt funktion till följd av trötthet och bristande kontroll över tarmfunktionen var de mest framträdande orsakerna till oro. Oron skapade känslor av stress, skuld och besvikelse. Deltagarna uttryckte önskemål att få prata om och synliggöra oron men hade också funnit egna sätt att hantera denna. Slutsats: Det finns ett kvarstående behov av att ventilera och få förståelse för sjukdomsrelaterad oro, även efter många års sjukdom. Personer med Crohns sjukdom måste få prata om sin oro, vara en aktiv partner i vården och tillsammans med vårdgivaren finna sätt att hantera oron så att denna kan lindras. / Background: A chronic, unpredictable disease as Crohn's disease provides physical, psychological and social stress. The disease affects everyday life, impairs quality of life and create worries. To conduct person-centered care requires insight into how this worry is experienced. Objective: To explore disease-related worries in persons with Crohn´s disease. Method: Eight women and four men between 30 and 64 who estimated their disease-related worries high or very high were identified. Interviews were conducted and analyzed with content analysis. Results: The analysis generated three categories: (1) Worries about the disease itself, (2) feelings around the worries, (3) management of the worries. The unpredictable course of the disease and the impaired function due to fatigue and lack of control of bowel function were the most prominent causes of worries. The worries created feelings of stress, guilt and disappointment. The participants expressed the wish to talk about and make the worries visible but had also found their own ways to handle it. Conclusion: There is a persistent need to vent and get an understanding of disease-related worries, even after many years of disease. Persons with Crohn's disease need to talk about their worries, be an active partner in healthcare and together with the health-care providers find ways to handle the worries so it can be relieved.
316

On the pathophysiological significance of CD154/CD40-mediated leukocyte-endothelial cell interaction / On the pathophysiological significance of CD154/CD40-mediated leukocyte-endothelial cell interaction

Gao, Dingcheng 07 May 2003 (has links)
No description available.
317

Neue Biomarker zur Überwachung der zellulären Immunität chronisch-entzündlicher Darmerkrankungen / New biomarkers for monitoring of cellular immunity of chronic inflammatory bowel disease

Weigand, Sebastian 24 June 2013 (has links)
Zurzeit existieren keine validen Biomarker, welche die Krankheitsaktivität oder das Rezidiv-Risiko von chronisch-entzündlichen Darmerkrankungen objektivierbar machen. Im Rahmen dieser Arbeit wurden neue Biomarker des Immunmonitorings auf ihren Nutzen bei der Beurteilung der Krankheitsaktivität von Patienten mit chronisch-entzündlichen Darmerkrankungen (CED) untersucht. Hierzu wurde bei 98 Patienten mit CED, nach positivem Votum der Ethikkommission, die intrazelluläre ATP-Konzentration der CD4+-Zellen gemessen, um diese mit der Krankheitsaktivität der Patienten in Bezug zu setzen. Die Patientendaten wurden zuvor mithilfe von standardisierten Fragebögen erhoben, um daraufhin die Krankheitsaktivitätsindices CDAI, HBI und SCCAI aus den klinischen Daten zu ermitteln. Es wurde keine signifikante Korrelation zwischen der ATP-Konzentrationen und der Krankheitsaktivität der Patienten festgestellt. Dies führte zu der Schlussfolgerung, dass Einzelmessungen der intrazellulären ATP-Konzentration von Lymphozyten nicht die Krankheitsaktivität von Patienten mit chronisch-entzündlichen Darmerkrankungen widerspiegeln. Ein signifikanter Unterschied der intrazellulären ATP-Konzentration CD4+-Zellen wurde allerdings zwischen Patienten mit und ohne Infliximab-Therapie nachgewiesen. Die Patienten, die unter einer Infliximab-Therapie standen, hatten signifikant niedrigere intrazelluläre ATP-Konzentrationen der Lymphozyten (p<0,01, Mann-Whitney-U). Dieses Ergebnis verdeutlicht, dass Infliximab als TNF-α-Blocker die Immunantwort bzw. die Aktivität von Lymphozyten inhibiert. Mithilfe der intrazellulären ATP-Konzentration wäre somit evtl. ein Werkzeug gegeben, um die Effektivität der Inhibierung der lymphozytären Immunreaktion durch TNF-α-Blocker zu kontrollieren. Weiterhin wurde bei 99 CED-Patienten die Anzahl regulatorischer T-Zellen im peripheren Blut bestimmt. Hierfür wurden die Zellen mithilfe von CD4-, CD25-, CD127- und FoxP3-Antikörpern angefärbt und mittels der FACS-Analytik quantifiziert. Anschließend wurde die so ermittelte Anzahl regulatorischer T-Zellen (CD4+CD25highCD127-FoxP3+-Zellen) mit der Krankheitsaktivität der Patienten korreliert. Auch dabei wurde keine signifikante Korrelation nachgewiesen. Bei der Unterteilung der Patienten in Gruppen mit erhöhter und erniedrigter Krankheitsaktivität deutete sich ein Unterschied bezüglich der Anzahl regulatorischer T-Zellen an, der jedoch nicht signifikant war (p=0,073, Mann-Whitney-U-Test). Diese Ergebnisse führten zu der Annahme, dass sich die durchflusszytometrisch quantifizierte Anzahl regulatorischer T-Zellen ebenfalls nicht als Surrogatmarker für die Krankheitsaktivität von Patienten mit chronisch-entzündlichen Darmerkrankungen eignet. Zudem wurde postuliert, dass die Quantifizierung von Tregs keine Hilfe bei der Unterscheidung zwischen den beiden Erkrankungen Morbus Crohn und Colitis ulcerosa liefern kann. Der tendenzielle Unterschied in der Anzahl von Tregs zwischen Patienten mit niedriger und erhöhter Krankheitsaktivität zeigt jedoch, dass regulatorische T-Zellen bei der Pathogenese von chronisch-entzündlichen Darmerkrankungen eine Rolle zu spielen scheinen. Allerdings deutet sich auch eine Abhängigkeit von weiteren pathogenen Faktoren in der komplexen Ätiologie von chronisch-entzündlichen Darmerkrankungen an. Bei 35 der CED-Patienten wurde zusätzlich eine weitere Methode zur Quantifizierung regulatorischer T-Zellen angewendet. Hierbei handelte es sich um einen DNA-Methylierungsassay, welcher die regulatorischen T-Zellen anhand einer spezifischen Demethylierungsregion der DNA (TSDR) ermittelt. Diese TSDR ist bei den Tregs demethyliert, während sie bei allen anderen Zellen des Blutes methyliert ist. Die Ergebnisse dieses Assays korrelierten jedoch nicht mit der Krankheitsaktivität der Patienten und korrelierten auch nicht mit den Ergebnissen für die Anzahl regulatorischer T-Zellen aus der FACS-Analytik. Diese Tatsache könnte zum einen darauf beruhen, dass in der FACS-Analytik im Gegensatz zum DNA-Methylierungsassay auch aktivierte T-Effektorzellen quantifiziert werden, welche nur transient FoxP3 exprimieren. Zum anderen werden mittels des DNA-Methylierungsassays auch CD8+FoxP3+-Zellen quantifiziert, welche keine oder geringe regulatorischen Eigenschaften besitzen und in der Durchflusszytometrie nicht quantifiziert werden. Zudem könnte eine fehlende Korrelation zwischen den Ergebnissen der beiden Verfahren auch daran liegen, dass sich die quantifizierten Tregs aus der Durchflusszytometrie auf die Gesamtheit der CD4+-Zellen beziehen, während sich die Tregs des DNA-Methylierungsassays auf die gesamten DNA-haltigen Zellen des Vollblutes beziehen. Zur besseren Vergleichbarkeit könnte in zukünftigen Studien ein Quotient aus Tregs und CD4+-Zellen gebildet werden. Zusammenfassend hat sich im Rahmen dieser Arbeit gezeigt, dass sich weder mithilfe der intrazellulären ATP-Konzentrationen von Lymphozyten noch der Anzahl regulatorischer T-Zellen eine Aussage bezüglich der Krankheitsaktivität oder des Rezidivrisikos von CED-Patienten treffen lässt. Da die chronisch-entzündlichen Darmerkrankungen derzeit nicht heilbar sind, werden weitere Surrogatmarker zum Objektivieren der Krankheitsaktivität benötigt, um Krankheitsrezidiven zeitnah entgegenwirken zu können.
318

The potential of proton magnetic resonance spectroscopy (1H MRS) in detecting early colonic inflammation and assessing the effect of various dietary fatty acids on modulation of inflammatory bowel disease in an animal model

Varma, Sonal 14 May 2008 (has links)
The objectives of our study were to determine the potential of 1H MRS in detecting (1) early colonic inflammation, (2) effects of various fatty acids on normal colon and (3) their effects on IBD. Sprague dawley rat fed with 2% carrageenan was used as a model of IBD. Flaxseed oil served as ω-3, corn oil as ω-6 and beef tallow as saturated fatty acid sources. Control group animals were fed 5% corn oil, whereas, those in high-fat diet groups received an additional 7% of the respective fatty acids. After 2 weeks, 1H MRS and histology were conducted on excised colonic mucosa. Statistical classification strategy (SCS) used for analyzing 1H MRS data achieved an accuracy of 82 % in stage 1, 90-100% in stage 2 and 96-100% in stage 3. This implies that 1H MRS is a sensitive tool to diagnose early IBD and the effects of dietary fat on IBD.
319

Microbial etiology of Inflammatory Bowel Disease: Microbial diversity and the role of Escherichia coli

SEPEHRI, SHADI 12 April 2010 (has links)
Inflammatory bowel disease (IBD), comprises Crohn’s disease (CD) and ulcerative colitis (UC), and is a chronic relapsing inflammation of gastrointestinal tract without any known cause or cure. Currently, it is accepted that IBD is a result of a dysfunctional immune response to commensal bacteria in a genetically susceptible host, and that environmental factors can trigger the onset or reactivation of the disease. This thesis considers the possibility of a specific pathogenic agent as well as an imbalance in the composition of the normal microflora in the pathogenesis of IBD. Gut biopsy tissues were taken from a population-based case-control tissue bank held at the University of Manitoba. Automated ribosomal intergenic spacer analysis (ARISA) and terminal restriction fragment length polymorphisms (T-RFLP) were employed to assess the diversity of gut microbiota. The phylogenetic, virulence and biochemical characteristics of Escherichia coli isolated from IBD biopsies were examined using multi-locus sequence typing (MLST), DNA microarray technology and API 20E system. Utilizing ARISA and T-RFLP, a remarkable increase in the order of unclassified Clostridia was detected in inflamed tissues, particularly in CD patients (P < 0.05). Moreover, species richness and diversity were the highest in non-inflamed IBD biopsies. Culture-based quantification detected a significantly higher number of E. coli in IBD tissues (P < 0.05). Phylogenetic analysis revealed the tendency of E. coli isolated from IBD patients to be grouped into separate clonal clusters based on their allelic profiles (P = 0.02). A link was detected between uropathogenic E. coli (UPEC) CFT073 and strains isolated from IBD, with regards to gene distribution and virulence, using microarray technology. Amino acid substitutions N91S and S99N in FimH, the adhesive subunit of E. coli type I fimbria, were significantly associated to IBD (P < 0.05). This study demonstrated an increase in the microbial diversity of non-inflamed IBD tissues and suggested a recruitment phase of bacterial adherence and colonization, before the inflammation sets in. Furthermore, E. coli isolated from IBD tissues were distinct from commensal strains in both clonal and virulence characteristics and shared remarkable traits with extraintestinal pathogenic E. coli. Features involved in bacterial adhesion to epithelial cells may hold the key to E. coli pathogenesis in IBD.
320

Human intestinal alkaline phosphatase : tissue expression and serum levels

Domar, Ulla January 1992 (has links)
Human alkaline phosphatase (ALP) comprises four isozymes, viz liver/bone/ kidney or tissue unspecific (AP), intestinal (LAP), placental (PLAP) and germ cell or PLAP-like alkaline phosphatase, with their main expression in specific tissues as indicated by their names. The isozymes are coded by different genes, but they are closely related, with more than 50% amino acid sequence homologies. Their biological function is unclear. In certain malignant and benign diseases, serum elevations of one or more of the isozymes occur, which is of diagnostic importance. In this study, the special expression of the intestinal isozyme in human tissues and sera, in normal as well as in pathological conditions, has been investigated by use of isozyme specific monoclonal antibodies. Monoclonal antibodies against the AP, IAP and PLAP isozymes were prepared, and specific assays developed, based on these monoclonal antibodies and the catalytic activity of the isozymes. By use of these assays the basal levels of all three isozymes were examined in selected normal organs. The isozymes were found to be expressed in measurable amounts in all the examined organs. IAP was immunohistochemically localized to the epithelial cells of membranes lining the ducts and tubules of the kidney, liver, pancreas and small intestine. Normal human serum contained all three isozymes. The AP isozyme constituted about 90% of the total ALP activity, the IAP isozyme less than 10% and the PLAP isozyme about 1%. Considerable interindividual variations of the serum IAP activity were observed. The serum activities of the IAP isozyme were related to the individual ABO blood group and secretor status. Non-secretors had low levels of IAP activity amounting to about one tenth of the activity in sera from blood group B or 0 secretors, while blood group A secretors had serum IAP activities in the same order as non-secretors. High individual day to day variations were observed. Fat absorption caused serum IAP to increase significantly for all persons, but it was rapidly cleared from the blood. We found that the release of IAP into the blood was linked to lipid absorption, but removal from the blood was not linked to lipoprotein clearance. Certain tumors of the testis expressed elevated levels of all three ALP isozymes. The highest activitiy of LAP was observed in one yolk sac tumor, in agreement with the endodermal origin of this tumor. In seminoma tissue the AP and PLAP isozymes were significantly, and IAP moderately elevated. Cirrhosis of the liver caused significantly increased serum levels of IAP besides the AP isozyme. In inflammatory diseases of the small intestine, normal serum IAP activities were observed. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1992, härtill 7 uppsatser.</p> / digitalisering@umu

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