Molecular, Cellular, and Tissue Engineering Commons^™

A Microfluidic Assay For Single Cell Bacterial Adhesion Studies Under Shear Stress, Amanda Trusiak

Electronic Theses and Dissertations

The study of bacterial adhesion to host cells is important in understanding bacterial pathogenesis and developing new therapeutic approaches. Here, we studied bacterial adhesion under shear stress using a novel microfluidic method. Specifically, the adhesion of a uropathogenic E. coli strain (FimHOn, ATCC 700928/CFT073) to mannose-modified substrates was studied under flow conditions. The FimHOn E. coli strain expresses FimH which is a mannose-specific adhesin found on the fimbriae that binds to glycoproteins on the epithelium. We developed a microfluidic method that mimics bacterial adhesion to urothelial cells. First, the microfluidic channels were modified by sequentially adsorbing BSA-mannose and BSA onto …

Investigating The Effect Of Dissolved Oxygen-Assisted Corneal Cross-Linking (Cxl) On Porcine Corneas, Julianni Dar

Electronic Theses and Dissertations

Corneal cross-linking is a clinical procedure that is known to stop the progression of keratoconus, an eye disease that affects the cornea’s structure, ultimately leading to vision loss in its advanced stages. The typical treatment plan includes riboflavin and UV-A exposure in the hope to increase the mechanical properties of the cornea. There are two types of CXL pathways, with Type-II CXL requiring oxygen. Naturally, the dissolved oxygen is limited in the cornea; therefore, limiting the effect of Type-II CXL. This study proposes to improve the Type-II CXL contribution by integrating dissolved oxygen during the standard CXL treatment used in …

Designing A Self-Regulating And Portable Heating Device For A Microfluidic Based Biosensor, Riya Mahajan

Discovery Undergraduate Interdisciplinary Research Internship

Paper-based biosensors are powerful microfluidic analytical devices that are potentially useful for a wide range of applications, ranging from medical diagnostics to agricultural and environmental monitoring. Molecular diagnostics have limitations because they need to send samples back to a centralized laboratory, which increases the cost and turnaround time of the test. This project aims to create a simple-to-use, low-cost, and portable heating system that would facilitate the creation of a field-deployable paper-based analytical device that can incubate the sample at elevated temperatures for conducting isothermal molecular assays. Our design aims to miniaturize a commercial water bath and will be fabricated …

A Versatile Python Package For Simulating Dna Nanostructures With Oxdna, Kira Threlfall

Computer Science and Computer Engineering Undergraduate Honors Theses

The ability to synthesize custom DNA molecules has led to the feasibility of DNA nanotechnology. Synthesis is time-consuming and expensive, so simulations of proposed DNA designs are necessary. Open-source simulators, such as oxDNA, are available but often difficult to configure and interface with. Packages such as oxdna-tile-binding pro- vide an interface for oxDNA which allows for the ability to create scripts that automate the configuration process. This project works to improve the scripts in oxdna-tile-binding to improve integration with job scheduling systems commonly used in high-performance computing environments, improve ease-of-use and consistency within the scripts compos- ing oxdna-tile-binding, and move …

The Interaction Of Angiotensin I And Ii On Calcified Aortic Valve Cells, Fah Sysavanh

Biomedical Engineering Undergraduate Honors Theses

Cardiovascular diseases affect the older population with limited treatments available. Aortic valve stenosis is a cardiovascular disease in which the aortic valve narrows, causing blood flow constriction and calcification.¹ The only treatment is to replace the valve, which can be costly and lead to other health complications.

The renin-angiotensin system (RAS) is a pathway that helps with maintaining cardiovascular homeostasis. Angiotensin I (ANGI) and II (ANGII) are hormones in the RAS that cause an increase in inflammation, stress, and blood pressure by binding to the Angiotensin Type 1 Receptor (AT1R).¹ Gelatin-based valve thin film (vTF) platforms were fabricated to investigate …

Sequential Illumination In A Tomographic Microendoscopic Probe For Imaging Tumor Microvasculature, Zachariah Neumeier

Biomedical Engineering Undergraduate Honors Theses

Knowledge of colorectal cancer biology is improving how we approach cancer treatment. Specifically, the tumor microenvironment and abnormal angiogenesis are of particular interest. Optical methods are a prime candidate for research of the tumor microenvironment due to their ability to quantitively assess tissue structure and perfusion in real time. Particularly, the “transport scattering regime” has been identified as a method of obtaining high-resolution images and reflectance spectroscopy data; this light scattering regime has been demonstrated compatible with endoscopic imaging systems. In this study, a proof-of-concept optical imaging system is presented, capable of resolving absorbers within scattering turbid media using a …

The Effects Of Microgravity On Human Endothelial Cells In Relation To Deep Vein Thrombosis, Allie Burgess

Biomedical Engineering Undergraduate Honors Theses

Deep vein thrombosis (DVT) is a condition where blood clots form in one or more of the deep veins of the body, causing leg pain and/or swelling, potentially leading to pulmonary embolism and/or stroke. The incidence of DVT among astronauts serving on the International Space Station has been shown to be greater than that of the general population, calling into question the effects of microgravity on human thrombolytic processes. Additionally, microgravity conditions have been shown to cause muscular atrophy and a decrease in muscle strength and mobility. Because collagen composes a large portion of muscle tissue, this study also assessed …

Hydrogel Drug Delivery Platform Integrity And Utilization Analysis, Joshua Carson Adams

Biomedical Engineering Undergraduate Honors Theses

Traumatic Spinal Cord Injury (SCI) generally results in permanent sensorimotor dysfunction. This is due to failed axonal regeneration at the site of injury. Recent studies have highlighted the use of stem-cell based therapies embedded in hydrogel to treat SCI. Embedding cell therapies in hydrogel provides a platform that increases the survival of both integrated grafted cells and stem cells/stem cell progeny. There are a variety of drug delivery agents for treating SCI such as neuro-regenerative cells and Schwann cells, however, single agents are not promising for functional regeneration. We propose a combinatorial approach using sciatic nerve (SN) extracellular matrix (ECM), …

Characterizing The Expression Pattern And Function Of Tartan During Drosophila Development, Alaina Baggett

Biomedical Engineering Undergraduate Honors Theses

The development of complex structures and organs by multicellular organisms relies on the ability of epithelial cells to self-organize. Epithelia are sheets of connected cells, and compartment boundaries are formed between certain epithelial cells to create distinct tissue compartments. Compartment boundaries are specialized cell-cell interfaces that are enriched for the cytoskeletal proteins actin and myosin, leading to straight cell edges under relatively high tension that act as fences keep cells from moving between compartments. In the model organism Drosophila melanogaster (fruit fly), compartment boundaries in the early embryo are established in response to the non-uniform striped expression of the cell-surface …

Isolation And Production Of Tandem Collagen Binding Domain From Clostridial Collagenase Colg And Developments In C1q Reagent Production For Future Molecule Characterization Work, Stephanie Beitle

Chemical Engineering Undergraduate Honors Theses

This thesis covers a two part project: the production methods to create a double collagen binding domain molecule with a growth factor for wound healing applications and the development of a new in-house production method for isolating C1q from bovine blood. The wound healing molecule was created using transformation, sonication, and purification before being tested via electrophoresis SDS page and Western blots to confirm the molecule’s presence. The C1q in-house production method utilizes an ultrafiltration flow cell rather than dialysis at a critical point in the process, allowing for researchers to not only be able to use a single small …

Modifications Of A Machine To Produce Clinically-Sized Angioplasty Balloons For Bifurcations, Natalie Smith

Biomedical Engineering Undergraduate Honors Theses

Coronary artery disease is the most common form of heart disease and the leading cause of death in the U.S. ("Heart Disease Facts | cdc.gov", 2021). Typically, coronary artery disease is a result of coronary stenosis, constriction of the coronary artery, which can cause heart failure, arrhythmia, or heart attack ("Coronary Artery Disease: Prevention, Treatment and Research", 2021). Angioplasty balloons are a common treatment method for coronary stenosis and work by placing a stent at the lesion site to widen the vessel and promote blood flow. A type of lesion which remains particularly difficult and relatively common to treat is …

Design Of A Four Channel Pulsatile Perfusion Bioreactor For Ex-Vivo Study Of Vascular Grafts, Thomas M. Fair

All Theses

Cardiovascular diseases are the leading cause of death in the United States. Atherosclerosis in peripheral arteries is a major contributing factor. Autologous saphenous vein grafts are the most common bypass grafts for treating peripheral artery diseases. A quarter of these grafts fail within a year, and around half have failed within 10 years of the initial surgery. Graft failure is attributed to the development of intimal hyperplasia indicated by the migration and proliferation of vascular smooth muscle cells, fibroblasts, and the deposition of extracellular proteins.

Increases in flow, pressure, the pulse frequency, and the differential of pressure that model an …

The Effects Of Metronomic And Maximum-Tolerated Dose Chemotherapy In Colorectal Cancer Angiogenesis: A Combined Approach Using Endoscopic Diffuse Reflectance Spectroscopy And Mrna Expression, Ariel Isaac Mundo Ortiz

Graduate Theses and Dissertations

Colorectal cancer (CRC) continues to be one of the most incident and deadliest types of cancer worldwide. Chemotherapy has proven effective to reduce tumor burden for CRC patients, but there are several disadvantages associated with the use of mainstay maximtolerated dose (MTD) chemotherapeutic strategies. Metronomic chemotherapy (MET) has been developed as an alternative that addresses the shortcomings of maximum-tolerated dose chemotherapy but so far its effectiveness as a neoadjuvant strategy for CRC has not been explored.

This dissertation uses a combined optics and molecular biology approach (using diffuse reflectance spectroscopy and mRNA expression) to study the changes in angiogenesis and …

Diffusive Dynamics Of Biological Macromolecules In The Cytoplasm Of Live Bacteria, Asmaa Ali Sadoon

Graduate Theses and Dissertations

Bacteria are small organisms that play important roles in our bodies and in maintaining our surrounding environment. However, bacterial infections are considered as one of the health diseases that threatens the lives of humans. Resistance of bacteria to antibiotics has made treating bacterial infections more challenging. With the emergence of many developed optical techniques, it has become possible to study various biological mechanisms of molecules inside these small organisms with high resolution and precise localization. In this research, single particle tracking photoactivation localization microscopy (sptPALM) technique was used to investigate the dynamics of fluorescent histonelike nucleoid-structuring proteins (H-NS) in live …

Characterization Of Fundamental Parameters That Modulate Acoustofluidic-Mediated Molecular Delivery To Cells., Connor Sterling Centner

Electronic Theses and Dissertations

Cell-based therapies represent the latest biotechnological revolution in medicine, but significant limitations exist in non-viral intracellular delivery techniques during manufacturing of cell therapies. To address these limitations, a novel acoustofluidic device was developed to deliver ultrasound waves into a flow chamber for rapid molecular delivery to human cells. Our acoustofluidic device delivers biomolecules by inducing expansion and collapse of exogenous gas-filled microbubbles (“cavitation”), which enhances molecular delivery to nearby cells. Experimental studies were conducted to characterize key parameters that influence acoustofluidic-mediated molecular delivery to human cells. A clinical ultrasound transducer was generally utilized with varying cationic microbubble concentrations. Intracellular delivery …

Erythrocyte Deformability In Response To Glucose Using Liquid Crystals, Jayden Goff

Biomedical Engineering Undergraduate Honors Theses

The worldwide prevalence of diabetes mellitus is rapidly increasing with about 9.3% of the adult population living with the disease. People with diabetes have trouble regulating their blood glucose levels which typically leads to hyperglycemia. Under normal physiological conditions, erythrocytes can undergo deformations in response to shear stress when passing through capillaries with a smaller diameter. Poorly managed hyperglycemia can lead to the glycosylation of erythrocyte membrane proteins and hemoglobin. This glycosylation leads to increased rigidity of the cells along with decreased deformability in response to mechanical stress; therefore, these cells have a higher susceptibility of getting stuck in the …

Clot Analogs For The Development Of Improved Treatment Methods In Ischemic Stroke, Charles A. Rieth

Biomedical Engineering Undergraduate Honors Theses

According to the CDC, nearly 800,000 individuals experience stroke each year in the United States [1]. Greater than 70% of strokes are of ischemic etiology and involve the occlusion of key arteries in the cardiovascular system [2]. Tissue plasminogen activator (IV-tPA) is the current gold standard for thrombolytic approaches [3]; however, this therapeutic is only effective between 3 and 4.5 hours from the patient’s last know well [4]. As a result, less than 5% of acute ischemic stroke patients receive IV-tPA. In order to increase the viability of AIS treatment as a whole, it is essential that thrombolytic techniques are …

Assessing The Potential Effectiveness Of Diffuse Reflectance Spectroscopy For Quantifying Neonatal Skin Properties Using Tissue Phantoms, Jack Murphy

Biomedical Engineering Undergraduate Honors Theses

Diffuse reflectance spectroscopy (DRS) has previously been shown to be effective at analyzing the optical characteristics of a wide variety of biological tissues, including the skin. In addition to being sensitive to the amount of blood and its oxygenation, DRS can be used to extract bilirubin levels and assess jaundice, a common complication in newborn infants. To assess its potential for being utilized in applications involving neonatal skin, we evaluated the utility of DRS for extracting hemoglobin and bilirubin concentrations from tissue phantoms. Phantom sets were created by including a known amount of scattering and by varying known concentrations of …

Investigating The Impact Of Hypoxia On Reactive Oxygen Species Generation Within Murine Breast Cancer Cells, Jared Mcpeake

Biomedical Engineering Undergraduate Honors Theses

When cancer metastasizes from a primary tumor site to secondary site through the bloodstream or lymph, the cancer becomes more difficult to treat. For this reason, it is vital to study what indicates the metastatic potential of a tumor. Current research has shown that cell lines with high metastatic potential display increased levels of metabolic adaptability over their nonmetastatic counterparts after undergoing hypoxic conditions. One method of assessing this adaptability is to measure the concentration of reactive oxygen species (ROS) produced by the cells while undergoing oxidative stress. In highly adaptable metastatic cells, an increase of ROS buildup within the …

The Influence Of Mmp14 On Angiogenesis In Chemotherapy-Treated Tumors, Abdussaboor Muhammad

Biomedical Engineering Undergraduate Honors Theses

Colorectal cancer is the third most common cancer in the world, and it is the fourth most common cause of cancer related death (1). There have been many significant advancements regarding the treatment of cancer which aim to shrink the size of tumors in patients. However, there is still more that needs to be understood about the many different factors that play a role in colorectal cancer development.

Angiogenesis is the process of forming new blood vessels from existing ones and it requires breaking down and remodeling of the extracellular matrix (ECM) in order to allow endothelial cells to migrate …