Real-time biosensor for the assessment of nanotoxicity and cancer electrotherapy

Knowledge of cell electronics has led to their integration to medicine either by physically interfacing electronic devices with biological systems or by using electronics for both detection and characterization of biological materials. In this dissertation, an electrical impedance sensor (EIS) was used to measure the electrode surface impedance changes from cell samples of human and environmental toxicity of nanoscale materials in 2D and 3D cell culture models. The impedimetric response of human lung fibroblasts and rainbow trout gill epithelial cells when exposed to various nanomaterials was tested to determine their kinetic effects towards the cells and to demonstrate the biosensor's ability to monitor nanotoxicity in real-time. Further, the EIS allowed rapid, real-time and multi-sample analysis creating a versatile, noninvasive tool that is able to provide quantitative information with respect to alteration in cellular function. We then extended the application of the unique capabilities of the EIS to do real-time analysis of cancer cell response to externally applied alternating electric fields at different intermediate frequencies and low-intensity. Decreases in the growth profiles of the ovarian and breast cancer cells were observed with the application of 200 and 100 kHz, respectively, indicating specific inhibitory effects on dividing cells in culture in contrast to the non-cancerous HUVECs and mammary epithelial cells. We then sought to enhance the effects of the electric field by altering the cancer cell's electronegative membrane properties with HER2 antibody functionalized nanoparticles. An Annexin V/EthD-III assay and zeta potential were performed to determine the cell death mechanism indicating apoptosis and a decrease in zeta potential with the incorporation of the nanoparticles. With more negatively charged HER2-AuNPs attached to the cancer cell membrane, the decrease in membrane potential would thus leave the cells more vulnerable to the detrimental effects of the applied electric field due to the decrease in surface charge. Therefore, by altering the cell membrane potential, one could possibly control the fate of the cell. This whole cell-based biosensor will enhance our understanding of the responsiveness of cancer cells to electric field therapy and demonstrate potential therapeutic opportunities for electric field therapy in the treatment of cancer.

Real-time Biosensor for the Assessment of Nanotoxicity and Cancer Electrotherapy

Knowledge of cell electronics has led to their integration to medicine either by physically interfacing electronic devices with biological systems or by using electronics for both detection and characterization of biological materials. In this dissertation, an electrical impedance sensor (EIS) was used to measure the electrode surface impedance changes from cell samples of human and environmental toxicity of nanoscale materials in 2D and 3D cell culture models. The impedimetric response of human lung fibroblasts and rainbow trout gill epithelial cells when exposed to various nanomaterials was tested to determine their kinetic effects towards the cells and to demonstrate the biosensor’s ability to monitor nanotoxicity in real-time. Further, the EIS allowed rapid, real-time and multi-sample analysis creating a versatile, noninvasive tool that is able to provide quantitative information with respect to alteration in cellular function. We then extended the application of the unique capabilities of the EIS to do real-time analysis of cancer cell response to externally applied alternating electric fields at different intermediate frequencies and low-intensity. Decreases in the growth profiles of the ovarian and breast cancer cells were observed with the application of 200 and 100 kHz, respectively, indicating specific inhibitory effects on dividing cells in culture in contrast to the non-cancerous HUVECs and mammary epithelial cells. We then sought to enhance the effects of the electric field by altering the cancer cell’s electronegative membrane properties with HER2 antibody functionalized nanoparticles. An Annexin V/EthD-III assay and zeta potential were performed to determine the cell death mechanism indicating apoptosis and a decrease in zeta potential with the incorporation of the nanoparticles. With more negatively charged HER2-AuNPs attached to the cancer cell membrane, the decrease in membrane potential would thus leave the cells more vulnerable to the detrimental effects of the applied electric field due to the decrease in surface charge. Therefore, by altering the cell membrane potential, one could possibly control the fate of the cell. This whole cell-based biosensor will enhance our understanding of the responsiveness of cancer cells to electric field therapy and demonstrate potential therapeutic opportunities for electric field therapy in the treatment of cancer.

Administrators' perspectives of culture at a multicampus community college

The purpose of this study was to explore how administrators’ perceived the campus and administrative cultures found on a single campus of a multicampus community college system. A review of the literature revealed that the culture found in higher education institutions contains a high degree of human interactions, has a myriad of cultures, and that individuals play a significant role in the maintenance or the evolution of the cultures present. The study site was Neighborhood Campus which is one campus of a large urban community college system containing a total of eight campuses, Urban College. Kuh’s conventional organizational models served to identify the model on Neighborhood Campus, Levin’s cultural definitions described the campus culture, and cultural definitions from Bergquist and Pawlak formed the framework for the administrative culture. The study was guided by the following research questions: What are the administrators’ perspectives of the campus culture on a community college campus and what are the administrators’ perspectives of the administrative culture on a community college campus? A qualitative case study method was used, data collection included interviews, document and videograph reviews, and observations of administrative meetings. The participants for the interview portion of the study included 10 individuals defined as administrators. ^ The study revealed that administrators’ perspectives of these cultures demonstrated five themes (student-centered, size, location, Hispanics, and family) served as contributors to the campus culture. The administrative culture was supported by six themes (size, team, collaboration, open, Inclusion, and rewards and recognition). ^ The findings revealed three of Kuh’s conventional organizational models (rational, bureaucratic, and collegial models) were seen as being in place at Neighborhood Campus. Levin’s traditional and service cultures were seen in the campus culture with the service culture demonstrating dominance. Using Bergquist and Pawlak’s definitions, components of the collegial, managerial, and developmental cultures appear to be present in the administrative culture with the collegial culture serving as the dominant administrative culture. ^ Through an understanding of these cultures and themes, administrators can provide leadership that is sensitive to these cultures, especially if institutional change is required.^