Biomedical Engineering and Bioengineering Commons^™

Antimicrobial Susceptibility Of P. Aeruginosa Clinical Isolates, Tian Gao

Theses - ALL

Long-term infection caused by P. aeruginosa poses a major threat to personal and public health, and causes billions of dollars in medical expenses. To develop more effective controls, it is important to accurately evaluate antibiotic susceptibility of clinical isolates and understand how susceptibility changes during the course of infection. Conventional drug susceptibility tests using nutrient-rich media have been questioned regarding their relevance due to the difference between the model in vivo test conditions and the environment in the patients. Here, we report that 27 clinical strains of P. aeruginosa isolated from cystic fibrosis patients showed higher drug resistance in Artificial …

A Computational Model For Calcium Signaling In Osteocyte Cell Cultures Under Mechanical Stimulation, Courtney Rose Ogando

Theses - ALL

Bone is a highly complex and organized tissue that is composed of an abundance of cells including the osteocyte. While it is known that osteocytes are responsible for the control of the bone remodeling process and the maintenance of calcium (Ca2+) homeostasis using their network of gap junction connections, their complete role is not yet fully understood. It is also known that various bone related diseases as well as cancer demonstrate an alteration of Ca2+ homeostasis during the progression of the disease. Previous researchers have combined computational modeling with experimental studies to gain a better understanding of cell-to-cell Ca2+ signaling …

Optical Printing Of Multiscale Hydrogel Structures, Zheng Xiong

Dissertations - ALL

Hydrogel has been a promising candidate to recapitulate the chemical, physical and mechanical properties of natural extracellular matrix (ECM), and they have been widely used for tissue engineering, lab on a chip and biophotonics applications. A range of optical fabrication technologies such as photolithography, digital projection stereolithography and laser direct writing have been used to shape hydrogels into structurally complex functional devices and constructs. However, it is still greatly challenging for researchers to design and fabricate multiscale hydrogel structures using a single fabrication technology.

To address this challenge, the goal of this work is the design and develop novel multimode …

Computational Investigation Of Biological Membranes, Allyson Karmazyn

Theses - ALL

Lipids are the building blocks of biological membranes, and the types of lipids that compose these cellular envelopes influence the physicochemical properties of the chemicals that can enter or exit the cell across the membrane. This work focuses on the lipid membrane compositions of eukaryotic (red blood cells) and prokaryotic (Pseudomonas aeruginosa) membranes. By analyzing the lipid-lipid and lipid-protein interactions results of the computational simulations, insights into lipid aggregation, bilayer leaflet behavior, membrane asymmetry, and small molecule transport through protein channels were obtained. The differences between prokaryotic and eukaryotic cell membranes are qualitative known; however, this work provides these concepts …

Computational Algorithms For Predicting Membrane Protein Assembly From Angstrom To Micron Scale, Nandhini Rajagopal

Dissertations - ALL

Biological barriers in the human body are one of the most crucial interfaces perfected through evolution for diverse and unique functions. Of the wide range of barriers, the paracellular protein interfaces of epithelial and endothelial cells called tight junctions with high molecular specificities are vital for homeostasis and to maintain proper health. While the breakdown of these barriers is associated with serious pathological consequences, their intact presence also poses a challenge to effective delivery of therapeutic drugs. Complimenting a rigorous combination of in vitro and in vivo approaches to establishing the fundamental biological construct, in addition to elucidating pathological implications …

Computational Algorithms For Predicting Membrane Protein Assembly From Angstrom To Micron Scale, Nandhini Rajagopal

Dissertations - ALL

Biological barriers in the human body are one of the most crucial interfaces perfected through evolution for diverse and unique functions. Of the wide range of barriers, the paracellular protein interfaces of epithelial and endothelial cells called tight junctions with high molecular specificities are vital for homeostasis and to maintain proper health. While the breakdown of these barriers is associated with serious pathological consequences, their intact presence also poses a challenge to effective delivery of therapeutic drugs. Complimenting a rigorous combination of in vitro and in vivo approaches to establishing the fundamental biological construct, in addition to elucidating pathological implications …

Predicting Tight Junction Formation Via Claudin Chimeras, Patrick Matthew Marsch

Theses - ALL

Tight junctions are vital to epithelial and endothelial barrier functions aiding in ion transport and preventing toxins from crossing into paracellular space. Claudins, made of four transmembrane helices and two extracellular loops, are a major part of the assembly of tight junctions along with other transmembrane proteins. The dimer interactions of two members of the 27-known members of the claudin family—claudin-2 and claudin-4—were analyzed. We created claudin chimera by switching claudin 2’s extracellular loops with claudin 4’s. The chimeras were analyzed using molecular dynamic simulations by comparing them to the natural claudins. This analysis provided new insight into the assembly …

Blood-Material Interactions With Degradable Shape Memory Polymer Foams, Ellen Barlow Shepherd

Theses - ALL

Shape memory polymer (SMP) foams are a class of smart materials that show promise for managing uncontrolled hemorrhage on the battlefield. The current standard treatments of gauze and tourniquets are not able to effectively control hemorrhage in up to 80% of combat injuries. Most hemostatic devices also require removal within 12 hours of application. Patient transportation to a facility for removal may not be possible within this time frame and the removal process itself can cause further damage to the wound. As an alternative hemostatic device, polyurethane SMP foams have shown to be effective and biocompatible hemostats; however, removal still …