Thesis (M.S.)--University of Michigan, 1975.

Thesis (M. Phil.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 208-230).

Thesis--Copenhagen. / Bibliography: p. 127-134.

Thesis (M.S.)--Texas State University-San Marcos, 2007. / Vita. Includes bibliographical references (leaves 68-75).

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Cells respond to chemical, mechanical and topographical cues both in vivo and in vitro. Much research has been carried out into the effects of chemical signals and to a lesser degree, mechanical. However, less is known about cell responses to topographical cues, particularly to topographies with nanoscale dimensions. Understanding how cells respond to topography is of particular interest to the field of tissue engineering, where it is crucial to characterise the effects that biomaterial surfaces have on the cells that they come into contact with. Observations of the impact that topographic signalling has on cells, within two tissue engineering systems, are discussed in this thesis. These systems are: polymer conduits for peripheral nerve regeneration and thin films for the replacement of the retinal pigment epithelium. Understanding the effects that micro and nano scaled topographies have on nerve and retinal cell regeneration is important for successful development and implementation of appropriate tissue engineered devices. In order to fabricate topographical patterns on biomaterial surfaces, a number of fabrication techniques were investigated. The fundamental requirement of these techniques was for reliable production of uniform nano and micro scale topographical patterns over large lateral areas (millimeter scale). Initially, the suitability of electrohydrodynamic lithography (EHDL) was assessed. EHDL is a relatively new technique, first published in 2000, which employs electrostatic forces to pattern thin polymer films. Subsequently, techniques traditionally associated with the computing industry, such as e-beam lithography and reactive ion etching, were evaluated. Following successful pattern fabrication, NG108-15 and ARPE-19 cells were cultured on grooved topographies. Against a baseline parameter of elapsed time, the cell morphologies and their propensity for alignment with the grooves was rigorously assessed and compared. ARPE-19 and NG108-15 cell responses differed from one another, and were sensitive to varying groove dimensions. Ultimately, the developing morphologies (for both cell types) proved to be clearly dependent on groove dimensions and elapsed time.

In this investigation the electrophysiological response to stimulation of the olfactory epithelium in response to trout scent and some of its chemical components was studied. Recordings were made both from the lamprey nasal sac and the catfish olfactory tract and the various responses described and compared with responses measured by other authors. / Thesis / Master of Science (MS)

The transporters primarily responsible for transporting important nutrients involved in energy metabolism have a wide substrate specificity setting up the potential for drug-nutrient transporter interactions. Pharmacological inhibition of nutrient transport across the lactating mammary and neonatal intestinal epithelial barrier can directly and indirectly affect growth and maturation of the developing neonate by either reducing the uptake of important nutrients by the neonate or by disrupting epithelial barrier integrity. My thesis focused on two transporters, OCTN2 and MCT1, expressed in immortalized intestinal and mammary epithelial cell cultures to assess the effects of their pharmacological inhibition on L-carnitine and butyrate flux, respectively, and polarized epithelial barrier integrity. Human colorectal adenocarcinoma (Caco-2) and bovine mammary (BME-UV) cell lines were grown into monolayers on 12-well tissue culture plates and subsequently exposed to the presence or absence of OCTN2 and MCT1 inhibitors for 6, 12, and 24 hours as well as 7 days. Failure to obtain a polarized mammary monolayer prevented the analysis of the direct effects of nutrient transport inhibition on nutrient flux forcing the focus on the indirect effects. To assess polarized epithelial barrier integrity, transepithelial electrical resistance and Lucifer yellow rejection rates were measured at each time point. No trend was noted between control and treated groups. To assess the acute and chronic effects of pharmacological exposure on polarized epithelial function, a limited appraisal of nutrient transporter expression and cellular homeostasis parameters was conducted. Following exposure at each time point, mRNA expression of OCTN1, OCTN2, MCT1, MCT2 and GADPH were measured using qPCR. Low mRNA yields resulted in an inability to assess transporter expression levels in the epithelial systems. Cellular homeostasis parameters were analyzed using the CellTiter-Glo Luminescent Cell Viability Assay, pH-Xtra Glycolysis Assay and MitoXpress Xtra Oxygen Consumption Assay. These assays measured ATP synthesis, glycolytic flux and cellular respiration, respectively. No significant trend was noted in ATP synthesis between control and treated groups. An upward trend in both glycolytic flux and cellular respiration was noted in treatment with both inhibitors in both cell lines. Complications in obtaining polarized monolayer forced the focus on the indirect affects, therefore, obtaining and utilizing a more accurate portrayal of the lactating mammary and neonatal intestinal epithelium is critical in answering this research question as both of these systems are highly synthetic and complex. By doing so, a more accurate representation of the effects of pharmacological inhibition of nutrient transporters essential for energy metabolism can be identified.

published_or_final_version / abstract / Biological Sciences / Doctoral / Doctor of Philosophy

Cystic Fibrosis (CF) is one of the most common heriditary diseases. This congenital condition, caused by CFTR gene mutation, affects gastrointestinal and respiratory system especially. The affection of respiratory system is considered the most serious life-threatening symptom. Pacients suffer from reccurent infections proceeding to the development of chronic inflammation and progressive pulmonary tissue destruction. A typical specific microoganism colonizating pulmonary tissue of thouse suffering from CF is recognised as Pseudomonas aeruginosa. Pulmonary infections caused by this microorganism are the most often cause of death in patients suffering from CF. Antiobiotics are the first-line therapy of this condition currently. Nevertheless, the need to find alternatives occurs due to antibiotics resistance development. Passive immunization by specific hen-egg-yolk antibodies against P. aeruginosa is a possible alternative. An observation of IgY influence on a bacterial adhesion to pulmonary epithelial cells required an appropriate model. In this context an appropriate adhesion testing method based on P. aeruginosa and pulmonary epithelial cells visualisation was searched. At first bacterial cells labelling was tested by CellTracker, resazurin, FITC and consequently PKH 26. P. aeruginosa fluorescent...