Defining the Role of Complement Factor B of the Alternative Complement Pathway in Diabetic Retinopathy

Poorly controlled complement activation is now associated with many pathologies, and recent evidence implicates complement dysregulation in the pathogenesis of several neovascular ocular diseases, including diabetic retinopathy. Although evidence that complement activation may contribute to vascular pathology is promising, crosstalk between the complement system and neovascularisation remains largely unclear. Taking a step back to understand the role of complemen in diabetic retinopathy would not only provide a more in-depth knowledge of the cellular and molecular mechanisms involved in disease pathogenesis, but it could also highlight novel therapeutic targets for DR and other vasoproliferative diseases in the eye. The objectives of the studies presented in this thesis were to test to test the hypothesis that complement has a novel function in angiogenesis which is separate from its characterised role as an immune surveillance system within the ocular environment. This work is specifically focused on exploring the role of the central component of the alternative complement pathway, complement factor B in regulating retinal angiogenesis. Initially, CFB expression was characterised using rodent models and human patient samples. In the retina of STZ-induced diabetic mice there was no difference in CFB expression between buffer-injected controls and STZ-induced diabetic mice. Similarly, characterisation of systemic CFB levels in human patient serum samples revealed no differences between control and diabetic patients at different stages of retinopathy. However, analysis of ocular CFB levels in human aqueous samples, revealed a higher expression in diabetic patients with retinopathy compared to diabetic patients without. The well-established mouse model of oxygen induced retinopathy was carried out to study CFB expression in pathologic vessel formation. RT-qPCR analysis demonstrated that CFB was significantly upregulated in mice retina subject to oxygen-induced retinopathy. To establish the impact of CFB on retinal vascular cell function and angiogenesis, in vitro and ex vivo angiogenesis assays were carried out. Results demonstrate that CFB was able to promote human retinal endothelial cell viability, proliferation, tube formation, Transwell migration, and aortic ring sprouting, thus indicating a pro-angiogenic role of CFB. Finally, to elucidate the mechanism through which CFB exerts its pro-angiogenic function the relationship between CFB and the VEGF signalling system was investigated using in vitro cultures of human retinal endothelial cells. Observations from these preliminary mechanistic studies revealed that CFB mediates VEGF gene expression, and VEGFR2 gene and protein expression. And that the pro-angiogenic function of CFB is upstream of, and acts through the VEGF signalling pathway. Several reports have implicated complement and complement related proteins in the development of DR. However, few studies have investigated the more precise role played by CFB and the mechanism(s) by which complement mediates its tissue damaging effects. Collectively, results from this study clearly indicate a pro-angiogenic role of CFB in DR associated neovascularisation

A “Wokeness” that Never Was: The Affective Economy of White Innocence and the Possibilities of Shame

This thesis critiques white liberal subjectivity, primarily through the work of Claudia Rankine. In Rankine’s The White Card, she critiques white liberal subjectivity through the form of a play, a space of encounter. In the case of The White Card, the play’s primary encounter appears to be about white people encountering Black people, but in actuality the encounter resides in white people encountering their own white liberal subjectivity. In order to further conceive of how white liberal subjectivity functions, I draw from Gloria Wekker’s “white innocence” and Sara Ahmed’s “affective economies” to craft the lens of an affective economy of white innocence. An affective economy of white innocence demonstrates how affects both comprise collectivities, such as the white liberal subjectivity, as well as stratify collectivities from one another. In addition to Wekker and Ahmed, I place Rankine’s critique of white liberal subjectivity in dialogue with the works of thinkers such as Hortense Spillers, Franz Fanon, Sara Ahmed, and Saidiya Hartman. While the affect of guilt structures much of the white liberal subjectivity, I also consider how the affect of shame, as understood by George Yancy and James Cone, may access an otherwise to the white liberal subjectivity. Through these dialogues, I encounter the harms of white liberal subjectivities as well as an otherwise to white liberal subjectivities

An Analysis of Novel Yeasts and Their Brewing Potential

Within the brewing community, there is a race to discover new ways to brew beers to create new flavor and smell profiles. Scientists across the globe are searching for novel species of yeasts which have the potential to enhance the flavor and smell of their beer. While most beers are brewed using one of a handful of domesticated yeast strains -- also known as pitching yeasts -- finding “wild” yeasts is one way to change fermentation products. Experimentation has been started on this front due to the wide array of properties that a wild yeast can change in a brew. For example, wild beers like the Belgium Lambic are often called sours due to a distinctive tart taste. This is achieved by adding bacteria, most commonly Lactobacillus, to the fermentation process to create lactic acid. Common flavors are fruity notes, maltiness, woodiness, and less common ones are citrus and peppery flavors. Yeasts can also determine the dryness of a beer. Many yeasts will also accentuate pre-existing flavors like honey and caramel and citrus. Discovery of new yeast strains adds variety to the brewing industry and partners the science industry with the commercial beverage industry. In choosing the ideal strain for industrial usage, we are evaluating the potential strains with respect to temperature tolerance, pH tolerance, and ethanol tolerance. Fermentation temperature is easily standardized by the temperature of the surroundings around the fermentation vessel. Generally, brewing temperatures are within 9-14℃ for lagers and 15-26℃ for ales.These temperature ranges are conserved across a wide variety of the commonly used yeasts. Temperature parameters will determine the base flavor profiles which each strain produces. pH also works to influence potential flavor. The pH of beers change dynamically during fermentation; all ferments start at around pH 5 and changes are monitored over time. Since pH drops largely during fermentation, the final pH determines the flavor profile of the final beer. Lastly, ethanol tolerance is an indicator for the amount of final alcohol that the yeast produces. During the fermentation process, yeasts consume sugars in the ferment and produce carbon dioxide and alcohol. Fermentation will end and the alcohol concentration will be capped when the alcohol concentration exceeds the yeasts tolerance. A yeast which is able to tolerate a higher concentration of alcohol will continue to ferment for longer periods. To discover new yeasts that might be appropriate for brewing, local fruits were harvested from Illinois Wesleyan University campus. The fruits collected were ground and strained. Cultures were isolation-streaked and grown on Yeast Peptone Dextrose (YPD) media with chloramphenicol at 30℃ for three days. The plates were then examined using colony morphology features which are consistent with known yeast. Once they were confirmed as yeasts, the cultures were analyzed using genetic tests and light microscopy imaging. Three isolates, which were confirmed as yeasts, were chosen for further work based on genetic identification and lab safety

Generic Preemption: Applying Conflict Preemption after Wyeth v. Levine

If a generic manufacturer does not have control over its safety warnings, can it comply with the obligations posed by state tort liability? State failure-to-warn actions evaluate whether a product manufacturer has met its obligation to warn consumers about known dangers associated with its product. In essence, if a manufacturer knows about a potentially dangerous outcome, it has a duty to warn its consumers. If the generic manufacturer can comply with a state duty to warn only by changing a label that the FDA will not allow it to change, it becomes impossible for the corporation to meet both requirements. This impossibility indicates that conflict preemption applies and the generic manufacturer ought not to be liable for claims arising under state tort law. This situation is distinct from branded pharmaceutical manufacturers who do have the ability to control and modify their safety labels. Part I begins by examining the doctrine of preemption, considering state tort liability and federal preemption theories. Part II reviews recent Supreme Court jurisprudence relevant to pharmaceutical preemption. Part III then looks at how generic drugs fit into the preemption landscape and concludes that preemption applies to generic drugs. Finally, Part IV evaluates the implications of preemption within the generic drug context