Diss. (sammanfattning) Göteborg : Göteborgs universitet , 2007. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 4 uppsatser.

Diss. (sammanfattning) Linköping : Univ., 2006. / Härtill 5 uppsatser.

Thesis (Ph.D.)--Duquesne University, 2009. / Title from document title page. Abstract included in electronic submission form. Includes bibliographical references (p. 129-140) and index.

abstract: Celiac Disease (CD) is now widespread as one in 133 people are currently diagnosed, while there were only one in 150 in 2006. Much of the research concerning CD is still in the early stages, as formal epidemiological studies are relatively recent. CD is aggravated by the consumption of gluten, which is found mainly in wheat, rye, oats, and barley. Not surprisingly, the rising prevalence of CD has created a significant business opportunity for food manufacturers in developing products that are tailored to CD sufferers. While the entire Gluten-Free (GF) industry has been experiencing double digit growth rates, the expansion in available snack foods has outstripped all others. Observation of GF snack food prices suggests that food manufacturers are responding to high retail prices associated with GF foods. However, GF foods are often also advertised with other attributes that generally sell for a premium over conventional foods. Therefore, whether the high retail price for GF snack foods can be attributed specifically to the GF attribute is an empirical question. The objective of this research is to determine whether there is a retail-price premium for GF snack foods and, if there is, to estimate its magnitude. A hedonic pricing model is used to answer this question. Specifically, a hedonic pricing model was applied to a unique dataset of snack food products in order to estimate the marginal value for the GF attribute, while controlling for a number of other important attributes. Results show that the GF attribute is both economically and statistically significant, implying a premium of nearly $1.86 above gluten-containing products. Production costs for smaller manufacturers can be two to three times higher for GF foods relative to non-GF foods, but this still implies an excess premium of over $0.50 (assuming 40% margins). However, high premiums may not last as large retailers are utilizing their influence over suppliers to keep retail margins low. Therefore, the primary implication of the research is that the rapid growth in recent years can easily be explained on economic grounds for large agribusinesses, as this implies a major profit opportunity. / Dissertation/Thesis / M.S. Agribusiness 2010

INTRODUCTION: Foods enter the oral cavity and mix with saliva. Some foods are not well tolerated, for instance, gluten proteins in individuals suffering from celiac disease (CD). Celiac disease is a chronic immune-mediated inflammation of the duodenum, triggered by gliadin component of gluten contained in wheat, barley and rye. In previous studies we showed that oral Rothia bacteria can degrade gliadin in vitro. The objective of this study was to gain more insights into the role of Rothia bacteria and subtilisin-A enzyme on gliadin digestion in vivo, with the ultimate goal to find new therapeutic options for CD. MATERIALS AND METHODS: Part I: Rothia bacterial proteins were analyzed for enzyme activity and subjected to LC-ESI-MS/MS. For in vivo, mice chow was prepared with and without R. aeria. Gliadin epitope abolishment was assessed in the mice stomach contents (n=9/group) by ELISA. Part II: Subtilisin-A was dissolved in various solutions, temperatures and incubation time to assess enzyme activity by using enzyme substrate (Suc-AAPF-pNA). Part III: PEGylation of subtilisin-A (Sub-A) was performed by mixing Sub-A with methoxy-polyethylene glycol (mPEG) and further encapsulated by polylactic-glycolic acid (PLGA). The activity of the modified enzyme to detoxify the immunogenic gliadin epitopes was evaluated at pH3.0. RESULTS: Part I: R. aeria gliadin-degrading enzyme was found to be a member of the subtilisin family. In vivo, gliadins immunogenic epitopes were reduced by 32.6%. Part II: Sub-A dissolved at pH1.5 showed a band of 27kDa, while it only showed bands below 10kDa when dissolved at pH7.0, suggesting auto-proteolysis. The enzyme activity was completely lost at temperatures exceeding 60°C and also reduced 4-fold after 6hr incubation at 37°C. Part III: PEGylation protected Sub-A from autolysis. The microencapsulated Sub-A-mPEG-PLGA showed significantly increased protection against acid exposure in vitro. In vivo, gliadin immunogenic epitopes were decreased by 60% in the stomach of the mice fed with chow containing Sub-A-mPEG-PLGA. CONCLUSION: The results provide proof for the contribution of oral Rothia bacteria to gliadin digestion and pharmaceutical modification can protect Sub-A from auto-digestion as well as from acidic insults, thus rendering the usefulness of coated subtilisins as a digestive aid for gluten degradation. / 2019-01-13T00:00:00Z

8 pp. / With the growing popularity of the gluten-free diet, there are many misconceptions surrounding gluten, carbohydrates, celiac disease, and gluten-sensitivity. This article explains the definitions of and differences between celiac disease, gluten-sensitivity, and other gluten-related conditions. The article also addresses the risks of adopting a gluten-free diet without a medical necessity to do so. Lastly, the article provides a healthy gluten-free recipe.

Introduction: The main objective of this thesis is to develop an algorithm to accurately identify cases of biopsy-proven Celiac Disease (CD) in children aged 6 months-14 years old from Ontario health administrative data. Method: CD cases diagnosed in 2005-2011 were identified from CHEO, and linked to the health administrative data to serve as reference for algorithms derivation. Algorithms based on outpatient physician visits for CD plus endoscopy billing code were constructed and tested. Results: The best algorithm selected based on performance from derivation study and clinical expertise consisted of an OHIP-based endoscopy billing claim followed by 1 or more adult or pediatric gastroenterologist encounters after the endoscopic procedure. The sensitivity, specificity, PPV, and NPV for the algorithm were 70.4%, >99.9%, 53.3% and >99.9% respectively. Conclusion: Study results suggest that the currently available Ontario health administrative data is not suitable for identifying incident pediatric CD cases.

Rothia mucilaginosa (Rm) is a gram-positive bacterium residing in the oral cavity. Recent studies in our laboratory have shown that this microorganism is able to cleave gluten, including immunogenic domains implicated in celiac disease. This can be beneficial to patients with celiac disease because exploitation of Rm can provide a novel mode of treatment. The enzymes responsible for this cleavage are as yet unknown. The purpose of this study was to optimize the transformation efficiencies of Rm cells through electroporation, with the ultimate goal to create knock-out mutants for enzyme activity. We have determined various aspects of Rm cells relevant for this project: (1) the growth curve characteristics of Rm; (2) the presence of endogenous restriction enzyme activities; and (3) the conditions facilitating Rm electroporation by varying electroporation voltages. Furthermore, electroporation and transformation of the plasmid pUC18 was conducted in Escherichia coli. The growth curve of Rm cells in BHI growth medium incubated at 37°C while shaking showed a doubling time of approximately 3 hours in the logarithmic growth phase. Using a cell sonicate of Rm cells incubated with Lambda DNA and four different restriction enzyme buffers, we found that there were no apparent endogenous restriction enzyme activities detectable. For the electroporation experiments, we used previously published protocols for the bacterium Staphylococcus aureus, as a standard condition to electroporate Rm cells. Those studies have shown that changing electrical parameters during the electroporation would yield a high efficiency rate of gram-positive bacterial transformation (Lofblom et. al., 2006; Metzler et. al., 1992). Therefore in our study, we increased the field strengths (kV*cm-1) to electroporate Rm cells. Rm cells could not be successfully transformed, and we observed that field strengths exceeding 18 kV*cm-1 destroyed Rm cells. On the other hand, the transformation of E. coli with pUC18 was successful. Our studies have laid the groundwork for investigating the transformation of Rm cells, and future studies can use the results obtained to further investigate ways to optimize transformation of Rm cells for potential utility in celiac patients.