Thesis (Ph. D.)--Georgia State University, 2008. / Title from title page (Digital Archive@GSU, viewed July 1, 2010) Jenny J. Yang, committee chair; Edward Brown, Giovanni Gadda, Zhi-ren Liu, committee members. Includes bibliographical references (p. 230-258).

Thesis (Ph.D.)--University of California, San Francisco, 2004. / Includes bibliographical references. Also available online.

Thesis (Ph.D.)--University of California, San Francisco, 2004. / Includes bibliographical references. Also available online.

Thesis (Ph. D.)--Drexel University, 2007. / Includes abstract. Includes bibliographical references (leaves 106-114).

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 148-166).

Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 104-120).

Thesis (MSD) --Boston University, Henry M. Goldman School of Dental Medicine, 2014 (Department of Endodontics). / Includes bibliographic references: leaves 41-49. / Sjogren's syndrome (SS) is a chronic, multisystem inflammatory disorder of multifactorial etiology resulting in loss of secretory function in the exocrine glands including salivary and lacrimal. Even though the pathophysiology progression of SS has been subject to great amount of research, the roles of different mechanisms remain inconclusive. The main dogma is that immune system pathology drives SS; however, there is no straightforward pathogenesis theory as there are multiple autoantibodies and changing proportions of different T-cell subsets with the progression of the disease along with many other different contributors. Interestingly, increasing evidence points to structural defects, including defective E-cadherin adhesion, to be involved in the etiology of SS. Recently, the Hippo signaling pathway has emerged as one of the main pathways regulating size of the organs and proliferation/ differentiation of cells, in part via interaction with E-cadherin junctions. Despite this, the role of Hippo signaling in the ... [TRUNCATED]

Dans le domaine des capteurs chimiques et biologiques, les besoins toujours croissants en termes de sensibilité, de rapidité et de sélectivité de l’analyse nécessitent le développement de couches sensibles transductrices de plus en plus performantes. Dans ce contexte et dans l’optique de pouvoir détecter de petites molécules non électroactives, telles que l’atrazine (ATZ), nous avons conçu, caractérisé et développé des couches sensibles constituées de polymères conducteurs fonctionnalisés à empreintes moléculaires (MICP) et les avons intégrées au sein de capteurs électrochimiques et gravimétriques. A partir de solutions d’acétonitrile contenant de l’ATZ, molécule empreinte en interaction avec des monomères fonctionnels dérivés du thiophène (FM = TMA, TAA, EDOT, TMeOH ou Th), différents polythiophènes FM-MICP de structures et de fonctionnalités différentes ont été électrosynthétisés sur substrats d’or et utilisés pour la détection de l’ATZ. Nous avons montré que les propriétés de reconnaissance des FM-MICP résultaient de la présence en leur sein d’empreintes moléculaires, fonctionnalisées par les résidus FM, qui conservaient la mémoire géométrique et fonctionnelle des molécules cibles. Néanmoins, une adsorption non-spécifique se produit systématiquement à la surface des couches sensibles et affecte par conséquent la sélectivité de la reconnaissance. Les techniques de caractérisation de surface employées nous ont permis de mettre en évidence l’influence de l’épaisseur et des propriétés structurales des couches sensibles sur l’efficacité de la détection. En outre, nous avons montré que du fait de la porosité de la couche polymère, le processus de reconnaissance se produisait en volume. Par ailleurs, des mesures électrochimiques corrélées à des calculs semi-empiriques ont permis de démontrer l’influence de la nature de FM d’abord sur la force de l’interaction ATZ-FM au sein de la solution de pré-polymérisation, ensuite sur le nombre d’empreintes moléculaires et enfin sur la sensibilité des FM-MICP vis-à-vis de l’ATZ. La couche TAA-MICP, qui présente un faible seuil de détection (10-9 mol L-1) ainsi qu’une large gamme dynamique (10-8 à 10-4 mol L-1), est la plus performante des couches sensibles puisqu’elle offre le meilleur compromis entre une détection spécifique de l’ATZ relativement élevée et une adsorption non-spécifique relativement faible. Enfin, le TAA-MICP a été utilisé comme couche sensible au sein d’un capteur électrochimique original à ondes acoustiques de surface (ESAW) dans l’optique de réaliser des mesures gravimétriques et électrochimiques couplées et simultanées. / In the field of chemical and biological sensors, the increased need for better sensitivity, faster response and higher selectivity during an analysis process, requires the development of more and more efficient transducing sensing layers. In this context, and with the aim to detect small non-electroactive molecules, such as atrazine (ATZ), we designed, characterized and developed sensing layers constituted by functionalized Molecularly Imprinted Conducting Polymers (MICP) and we integrated them into electrochemical and gravimetrical sensors. Starting from acetonitrile pre-polymerization media containing ATZ as template molecules in the presence of thiophene-based functional monomers (FM, namely TMA, TAA, EDOT, TMeOH or Th), differently functionalized and structurally different polythiophene-based FM-MICP films were electrosynthesized onto gold substrates and used for ATZ detection. The sensing properties of FM-MICP layers were shown to result from the presence in their backbones of pre-shaped FM-functionalized imprinted cavities which keep the memory of the targets. Nevertheless, non-specific adsorption onto the surface of the sensing layers takes place systematically, which affects the selectivity of the recognition process. Thanks to surface characterization techniques, we highlighted the influence of the thickness and of the structural properties of the layers on the efficiency of the recognition process. Besides, this latter was shown to operate in the bulk of the polymer matrixes thanks to layers porosity. On another hand, electrochemical measurements correlated with semi-empirical calculations demonstrated the influence of the nature of FM on the strength of the ATZ-FM interaction in the pre-polymerization medium, and then on the number of ATZ molecular imprints and on the sensitivity towards ATZ of the FM-MICP layers. We showed that TAA-MICP, which presents a low limit of detection (10-9 mol L-1) and a large dynamic range (10-8 to 10-4 mol L-1), is the best sensing layer since it offers the best compromise between high level of specific detection of ATZ and low level of non-specific adsorption. Finally, TAA-MICP was used as sensitive layer in an original Electrochemical Surface Acoustic Wave sensor (ESAW) which enabled simultaneous coupled gravimetric and electrochemical measurements.

Plasmodium spp. and Trypanosoma brucei spp. are protozoan parasites with complex lifecycles, each having to adapt to the diverse environments of their insect vector and mammalian host. Each has multiple developmental forms that differ in their morphology and metabolism. Differentiation between these forms is a tightly regulated and often synchronised process in response to changes in the parasite's environment. The molecular mechanisms by which they perceive and respond to such environmental changes are largely unknown. The Plasmodium and T. brucei genomes encode a homologue of the phylogenetically widespread GPR89 family of putative receptors or channels. The mammalian GPR89 homologue has been implicated in the regulation of Golgo acidification, whilst in plants it has been shown to be involved in G protein signally pathways. This study set out to characterise the Plasmodium and T. brucei GPR89 proteins in order to assess their potential role as environmental sensors. Bioinformatic analyses demonstrated that the GPR89 proteins are a highly divergent family of multi-transmembrane domain proteins that may perform a channel or transporter function. Several expression strategies were employed to evaluate the role of the GPR89 proteins. Functional insight was gained from the ectopic expression of both the T. brucei and Arabidopsis thaliana GPR89 proteins in T. Brucei cells. Over-expression of TbGPR98 causes premature stumpy formation in pleomorphic T. brucei cells. This phenotype was replicated by over-expression of a A. thaliana homologue in T. brucei despite signigicatnt sequence divergence. Furthermore, both were demonstrated to act on the same pathway as the putatuve RNA binding protein, RBP7 that was receontly identified in a genome-wide screen for components of the stumpy differentiation pathway. Hence, TbGPR89 is likely a compnent of the slender to stumpy differentiation pathway in bloodstream form trypanosomes and there appears to be functional complementarity between T. brucei and A. thaliana GPR89 proteins.

Magister Scientiae - MSc / Plants in the field are exposed to multiple stresses and their response to these various stresses determines their capacity to survive. Plants can use multiple signaling pathways and signals to mediate their response; for example, at least four different signal pathways have been identified for water-deficit stress (Shinozaki and Yamaguchi-Shinozaki, 1997; Xiong et al., 2002). Different forms of stress may activate or utilize the same components, including proteins and other signaling molecules. Signaling molecules such as jasmonic acid (JA) are involved in multiple stress response and development in plants (Creelman and Mullet, 1995, 1997; Turner et al., 2002). However it is the specific combination of various components of the signaling network coupled with spatial and temporal factors that allows the plant to mount a directed response to any given stress factors. Systemic defense responses thus provide an attractive model for the study of cell-to-to cell signal transduction pathways that operates over long distances (Lucas and Lee, 2004). Cellular and physiological evidence suggest the presence of a novel class of systemic mobile plant molecule that is recognized by antibodies against vertebrate atrial natriuretic peptides (ANPs). It has been demonstrated that a recombinant Arabidopsis thaliana natriuretic peptide analogue (AtPNP-A) molecule can induce osmoticumdependent water uptake into protoplast at nanomolar concentrations thus affecting cell volume and hence plant growth. In this study we confirm that active recombinant protein causes swelling in Arabidopsis mesophyll cell protoplasts (MCPs). / South Africa