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Thesis PlanB (M.S.)--University of Wisconsin--Stout, 2007. / Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 186-197).

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No description available.

Cranberry (Vaccinium macrocarpon), a commercially grown evergreen dwarf shrub, is a dominant taxon in temperate bogs in North America. It spreads clonally by runners, and reproduces sexually predominantly by self-fertilization on upright stems. The objective of this project was to investigate genetic and clonal variation and phenotypic plasticity of V. macrocarpon. Specifically, I wanted to test whether there exists an inverse relationship between population genetic variation and the amount of overall phenotypic plasticity of vegetative characteristics. As background information I assessed the vegetation and edaphic factors of marginal cranberry bogs found in the mid-to-southern Appalachians. A gradient of nutrient availabilities was found among bogs that was positively associated strongly with the dominance of the more generalist Rubus hispidus and negatively with ericaeous bog shrubs such as V. macrocarpon. Eutrophication may lead to the replacement of endemic bog species with generalist plastic species. Theoretically, it would be plausible for environmental heterogeneity or stress to allow selection for more phenotypically plastic clones within a species. A single adaptively plastic clone for growth strategy could sweep a site, excluding intraspecific competitors. That is, selection could favor clones with high plasticity that could subsequently lead to a loss of genetic variation within a population. The environmental and genetic conditions favoring this would more likely exist in distributionally marginal sites because of spatial and temporal heterogeneity and island-like biogeography. Field and common garden experiments in which nutrients were manipulated were performed to test for an inverse relationship between phenotypic plasticity and genetic heterogeneity. Random amplified polymorphic DNA (RAPD) profiling was coupled with ecological measurements of plant growth on the experimental clones and other clones from the experimental populations to estimate genetic heterogeneity. Genetic heterogeneity was found to be significantly lower in marginal populations than in central populations. Phenotypic plasticity was somewhat higher in a more marginal population in the field sites, but direct statistical comparisons could not be made. The common garden study was inconclusive, possibly due to transplant shock, but a trend among natural populations was towards higher plasticity among marginal clones. Additional research on other species is needed to clarify the possible inverse relationship between phenotypic plasticity and genetic variation within populations. / Ph. D.

The adhesion of bacteria to uroepithelial cells or urinary catheters is the first step in the development of biofilm formation and urinary tract infections (UTIs). Previous research has suggested that consumption of cranberry juice can prevent the recurrence of UTIs by decreasing bacterial adhesion since isolated compounds in cranberries, known as A-type proanthocyanidins (PACs), change the conformation of proteinaceous fimbriae that help attach bacteria to epithelial cell receptors. Most clinical and laboratory studies have shown the effects of cranberry juice cocktail (CJC) on large communities of bacteria; however, very few studies have evaluated how cranberry affects the adhesion forces of a single bacterium as well as effects on cellular composition and biofilm formation. We used atomic force microscopy (AFM) to investigate the effects of CJC and PACs on the adhesion forces between E. coli and a silicon nitride tip. Bacterial cultures were grown in tryptic soy broth (TSB), supplemented with 0 and 10 wt.% light cranberry juice cocktail (L-CJC) or 128 µg/mL PACs. E. coli bacteria were continuously cultured in the presence of cranberry products up to twelve times. Experiments were conducted at different scales to test bacterial attachment and adhesion forces. At the macroscale, bacteria were incubated with uroepithelial cells and the number of bacteria attached per uroepithelial cell was determined. In nanoscale experiments, the forces of adhesion between E. coli and a silicon nitride AFM tip were probed for bacteria grown in L-CJC or PACs for different numbers of culture times. Successive replacement of media and continued culture in L-CJC and PACs resulted in a significant decrease in adhesion forces for E. coli strains. Finally, during the continuous exposure of L-CJC to bacteria we examined the growth, morphology, and ability to form biofilms of E. coli. We found a decrease in growth rates related to changes in Gram staining with increasing number of cultures in L-CJC. Growth of bacteria in L-CJC or PACs inhibited the development of biofilms on polyvinyl-chloride, which can model biofilm formation on urinary catheters. We also determined that growth of E. coli in L-CJC results in prevention of the expression of indole which can be linked to the inhibition of biofilm formation. Our results help support the molecular mechanisms for the role of cranberry in preventing the adhesion of E. coli to biotic and abiotic surfaces, thus helping to scientifically validate the use of cranberry juice as a prophylactic treatment for the prevention of UTIs.

The North American cranberry plant (Vaccinium macrocarpon Aiton) is a wetland crop species grown commercially in natural or constructed peat or sandy soil basins. Since production is highly water dependent, water requirements are very significant and have prompted growers to explore new water management practices to improve irrigation efficiency and protect water resources. One way of conserving and better managing water, given the infrastructure in place, would be to develop sub-irrigation. / The design of a subsurface irrigation system requires the evaluation of various soil properties. This was undertaken at four established cranberry production sites, situated near Saint-Louis-de-Blanford, Quebec. Two of the fields contained a sandy soil, and the other two were peat soils. Soil physical properties measured included: saturated hydraulic conductivity, bulk density, porosity, soil moisture characteristic curves and particle size distribution.

Nosocomial, or hospital acquired, infections, are ubiquitous within the modern clinical setting leading to over $5 billion annually of related healthcare costs in North America. All indwelling devices are highly susceptible to bacterial colonization where physico-chemical interactions between bacteria and biomaterial surfaces have been implicated as determinant factors in the fate of the initial adhesion processes. It has been proposed that by exploiting interference strategies within this critical step of infection the ability to create 'non-infective' biomaterials may be developed. / This thesis demonstrates the effectivity of North American cranberry (Vaccinium macrocarpon) derived proanthocyanidins in preventing the adhesion of pathogenic bacteria to biomaterial surfaces. Specifically, using a model of catheter associated urinary tract infection, significant reductions in initial adhesion of uropathogenic Escherichia coli and Enterococcus faecalis to PVC and PTFE were observed. With the application of colloidal theory, a mechanism of steric interference was determined as responsible for these effects. / The evidence presented implicates PAC as a molecule of interest for the development of novel biomaterials with increased resistance to bacteria colonization.