No description available.

No description available.

No description available.

The purpose of this study was to determine the prevalence of known risk factors associated with diabetes among James Moody Adams (JMA) clinic patients in order to develop and test educational material and clinical interventions to reduce the incidence of pre-diabetes and uncontrolled Type II Diabetes. The research objectives for this study focused on: 1. prevalence of Type II Diabetic patients at the Clinic; 2. pre- and post-test knowledge level of patients regarding their Type II Diabetes; 3. relationship between dependent variables (body mass index [BMI], blood glucose level, blood pressure, waist circumference, level of tobacco use, and level of depression) and the independent variables (age, gender, family history of diabetes, socio-demographical data [education level, level of income], literacy, and exercise regimen, medication, and diabetes knowledge); 4. effectiveness of a nutritional and lifestyle modification intervention program to control Type II Diabetes. Two hypotheses tests: 1. decrease blood glucose levels of Type II Diabetes Mellitus patients; 2. decrease weight by 5 percent among pre-diabetic and Type II Diabetes Mellitus patients. A follow-up survey determined participant's reflection on key dimensions of the study and impact of unforeseen political unrest that occurred during this study. The methodology was a case study with clinical and educational intervention across a 6 months. The population included patients presenting at the JMA clinic at onset of the study; an initial sample of 96 reduced to 48 due in part to political unrest was still within power test specification. Instrumentation include researcher developed, standard of care clinical practice and standardized forms. Analyses utilized descriptive statistics and t-test. Significant gain was determined for diabetic knowledge (p < 0.001); and significant decrease in Type II Diabetic blood glucose with p = 0.031. An important conclusion is that implementing a Type II Diabetic prevention program is feasible and effective in this study. Future recommendations include replication of the study and implementation of protocols and education that were successful in this study. / Ph. D.

Researchers of <i>Clostridium perfringens</i>, a Gram-positive anaerobic pathogen, were lacking a tightlyregulated, inducible promoter system in their genetic toolbox. We constructed a lactose-inducible plasmid-based system utilizing the transcriptional regulator, BgaR. Using the <i>E. coli</i> reporter GusA, we characterized its induction in three different strains of <i>C. perfringens</i>. We then used a newly-developed mutation system to create in-frame deletion mutants in three genes with homology to Type IV pilins, and we used the promoter system described above to complement the mutants. We analyzed each pilin for localization and expression, as well as tested each of the mutants for various phenotypes frequently associated with type IV pili (TFP) and type II secretion systems. PilA2, PilA3, and PilA4 localized to the poles of the cells. PilA2 was expressed in the wildtype when <i>C. perfringens</i> was grown on agar plates, and the PilA3 mutant lacked a von Willebrand factor A domain-containing protein in its secretome. We used our promoter system to express GFP-tagged versions of the TFP ATPase homologues and view them in cells growing on surfaces. We saw that PilB1 and PilB2 co-localized nearly all of the time, while a portion of PilT was independent of the PilB proteins. PilT appeared necessary for the localization of PilB, and it localized independently of TFP proteins in <i>Bacillus subtilis</i>. PilT's typical localization in <i>Bacillus subtilis</i> was disrupted when the GTPase and polymerization activity of cell division protein FtsZ was blocked, suggesting that PilT associates with cell division proteins. / Master of Science

Mechanical stiffening of the interstitial space in the lung – the protein-rich extracellular space between the alveoli and capillaries – plays an important role in modulating epithelial cell behaviors that contribute to cancer and idiopathic pulmonary fibrosis (IPF) disease etiologies. However, the effects of substrate stiffness and breathing-like stretch are not well understood in the context of cancer. In this thesis project, we utilize RNA sequencing to understand how the mechanical properties of extracellular environments modulate cancer related cells. To accomplish this goal, we examined the behavior of lung cancer derived A549 cells, cells that have epithelial lineages, on a biomimetic lung-on-a-chip devices. Importantly, our biomimetic devices allow us to modulate the stiffness of the interstitial space to have soft properties similar to those observed in healthy lung and stiff properties mimicking fibrotic tissues. After growing A549 cells on our biomimetic devices and plastic plate controls, we extracted and purified RNA for mRNA sequencing to examine differential gene expression. Subsequent gene ontology analysis found that differentially expressed genes are involved in cell cycle, metabolism, and cell migration. Connecting these pathways using KEGG analysis we identified pathways of downregulated or upregulated genes related to cancer and metastasis. Based on these results, changes in the interstitial stiffness surrounding A549 cells can change their behaviors and lead to activation of cancer pathways.

Neurofibromatosis Type II (NF2) is a neurological disorder arising from mutations in the rif2 gene. NF2 is characterized by formation of bilateral vestibular schwannomas. These tumors arise from Schwann cells, the myelin-forming glia in nerves. Schwannoma cells lose the characteristic bipolar, spindle morphology and assume a round fibroblast-like phenotype. Phenotypic de-differentiation of schwannomas has been attributed to increased levels of Cdc42/Rac-GTP and activation of downstream pathways. The n/2 gene encodes the tumor suppressor called merlin. It is targeted to the plasma membrane by direct binding to paxillin at paxillin-binding domain 1, encoded by exon 2 of the nj2 gene. At the plasma membrane, merlin associates with B1-integrin and erbB2/3 receptors and actin regulating proteins. We hypothesize that merlin modulates actin polymerization, and thus cell shape, by controlling the activity of actin filament regulating proteins. We developed an in vitro model ofNF2 using ad-ere ( ad-Cre) viral mediated deletion of nj2 exon 2 in primary mouse Schwann cells. Within 5 days of ad-Cre infection, merlin levels fall to 40% of normal levels in Schwann cells. Moreover, the expressed merlin protein has the expected lower molecular weight and does not target to the plasma membrane. Schwann cells expressing this mutant merlin lose their characteristic bipolar shape. We tested the activation levels of2 candidate Cdc42/Rac dependent-actin regulating proteins in these cells. Using immunofluorescence, we found that the activity of these proteins increased dramatically within 4 days of n/2 inactivation. This increase in activity was then confirmed with western blotting. We conclude that the function of these actin-filament regulating proteins could contribute to changes in morphology associated with schwannoma formation in NF2.

L’épidermolyse bulleuse simplex (EBS) est caractérisée par un décollement intra-épidermique au niveau de la couche basale de l’épiderme aboutissant à la formation de bulles et de cloques cutanées. L’EBS est causée par des mutations au niveau des gènes qui codent pour la kératine 5 (K5) ou la kératine (K14), qui sont transmises majoritairement selon un mode autosomique dominant. L’EBS affecte environ 1/50 000 à 1/30 000 personnes dans le monde et elle est considérée comme une maladie orpheline. Dans cette étude, les kératinocytes ont été isolés de biopsies de la peau de patients atteints d’EBS ayant des mutations dans le gène KRT14 et de témoins non atteints. Des essais thérapeutiques utilisant l’interféron gamma (IFN-γ) ont été réalisés afin de stimuler la production de la K15. Les résultats ont révélé que l’IFN-γ réduit l’expression et la production de la K15 contrairement à ce que suggérait la littérature. Cette discordance pourrait s’expliquer par un effet « régulateur » de l’IFN-γ sur la K15 lorsque les cellules seraient activées. Cette hypothèse a été validée par l’augmentation de l’expression de la KRT16 qui est considérée comme un marqueur de préactivation des kératinocytes. Ainsi, l’IFN-γ ne semble pas être une cible thérapeutique potentielle pour l’EBS causée par une mutation de KTR14 (R125S).

L'interféron-y est une cytokine produite entre autres par les lymphocytes T effecteurs et est impliquée dans la réponse immunitaire ainsi que dans les maladies inflammatoires de type Thl. Les intégrines liant le collagène ont été récemment impliquées dans les maladies inflammatoires de type Thl. Puisque les lymphocytes T effecteurs expriment ces intégrines, nous avons émis l'hypothèse que l'adhésion des lymphocytes T au collagène peut être impliquée dans la régulation de l'expression de l'interféron-y. Nous avons déterminé que le collagène de type I, par l'intermédiaire de son récepteur, l'intégrine oc2pi, augmentait significativement l'expression et la production de l'interféron-y induite par le TCR. Des expériences d'inhibition ont démontré que les MAP kinases ERK et JNK, mais pas p38 sont nécessaires pour la production d'interféron-y et que le collagène de type I augmentait significativement l'activation de ces deux MAP kinases. Le collagène de type I augmente également l'activation de la voie PI-3 kinase/AKT qui est aussi nécessaire à l'expression de l'interféron-y. Par contre, le collagène de type IV, liant l'intégrine al pi, n'augmente pas l'expression d'interféron-y, probablement dû au fait qu'il n'augmente pas l'activation de JNK induite par le TCR. Nos résultats suggèrent que l'intégrine oc2pi exprimée chez les lymphocytes T effecteurs peut contribuer au développement des maladies Thl en augmentant l'expression de l'interféron-y. Ainsi l'intégrine a2pi pourrait être une cible thérapeutique potentielle dans le traitement des maladies inflammatoires de type Thl. / Interferon-y is a cytokine produced by Thl cells and is involved in cell-mediated immune response and Thl inflammatory diseases. Collagen binding integrins have recently been involved in the development of Thl inflammatory diseases. Since Thl cells express these integrins, we hypothesized that adhesion of T cells to collagens could be involved in regulating the expression of interferon-y. We demonstrated that collagen type I, through its receptor the integrin a2pi, augmented significantly the expression and production of interferon-y induced by the T cell receptor (TCR). Inhibition studies demonstrated that the MAP kinases ERK and JNK but not p38 were necessary for interferon-y production and that collagen type I augmented significantly the TCR-dependant activation of these two MAP kinases. Similarly, collagen type I also augmented the activation of the PI-3 kinase/AKT pathway which is also required for the expression of interferon-y. Our results indicate that the a2|31 integrin expressed on effector T cells can participate in development of Thl diseases by augmenting the expression of interferon-y through the ERK, JNK and PI-3 kinase/AKT pathways. In contrast, collagen type IV, which binds to a l (31 integrin, does not increase interferon-y expression probably because it does not increase TCR-dependant activation of JNK. Our study suggests that a2(31 integrin could contribute to Thl diseases by increasing the production of interferon-y and therefore could be a potential target in the treatment of Thl inflammatory diseases.

Le cancer du sein et le diabète de type II sont deux pathologies chroniques majeures chez la femme, qui sont suspectées de partager de nombreux facteurs de risque. Mais leurs étiologies demeurent encore partiellement inconnues,notamment en ce qui concerne certains facteurs alimentaires, ou encore certaines composantes du syndrome métabolique. Les données de la cohorte française E3N ont ainsi été utilisées pour évaluer les associations entre la consommation d’alcool, de café, de viande, les apports en vitamine D et les risques de cancer du sein et de diabète de type II. De plus, s’il est avéré que le syndrome métabolique est associé à un sur-risque de diabète, des questions persistent quant à l’influence de certaines composantes du syndrome métabolique, tels que le taux de cholestérol ou certains facteurs anthropométriques, sur le risque de cancer du sein. Dans l’évaluation des risques respectifs de cancer du sein et de diabète de type II, nos travaux ont mis en évidence qu’une consommation élevée de café était associée à une diminution de risque de diabète de type II, qu’un taux sérique élevé de vitamine D, ou un apport élevé en vitamine D alimentaire parmi les femmes résidant dans les zones de forte exposition solaire, étaient associés à une diminution de risque de cancer du sein. Si une consommation nulle ou modérée d’alcool s’est avérée être associée à une absence de sur-risque de diabète de type II, la consommation d’alcool était quant à elle associée à un sur-risque de cancer du sein. Nos résultats sont également en faveur d’une limitation de la consommation de viande préparée industriellement. Par ailleurs, maintenir un indice de masse corporelle et un tour de hanche le plus faible possible, à l’aide d’un régime alimentaire équilibré et une activité physique régulière,permettrait également de réduire les risques de cancer du sein et de diabète de type II. / Breast cancer and type II diabetes are two of the main chronic diseases in women and are suspected to share common risk factors. But their etiologies are still partially unknown, in particular concerning some dietary factors and some parameters of the metabolic syndrome. If evidence is convincing that themetabolic syndrome is associated with an increased type II diabetes risk, questions remain unanswered regarding cholesterol level, anthropometric factors and breast cancer risk. The French E3N cohort database was thus used to evaluate the associations between alcohol, coffee, meat consumption and serum concentration and dietary intake of vitamin D on the risks of breast cancer and type II diabetes. We showed that a high coffee consumption was associated with a decreased risk of type II diabetes, and that a high vitamin D blood level was associated with a decreased risk of breast cancer. Whereas null or moderated alcohol consumption was not related to type II diabetes risk, an increase in alcohol consumption was associated with an increased breast cancer risk. Our results suggested limiting processed meat consumption. They also favoured recommendation towards low body mass index ora low hip circumference by a healthy diet and a regular physical activity so as to decrease breast cancer and type II diabetes risks.