Biomedical Engineering and Bioengineering Commons^™

The Effects Of Compression Wrapping Techniques And Primary Wound Dressings On Leg Skin Interface Pressure, James Cox

All Theses

Peripheral edema affects approximately 20% of people in the US over the age of 50 and is frequently encountered among individuals with conditions such as heart disease, prolonged immobility, and venous insufficiency.¹ Compression is an established therapeutic tool utilized for the management of several chronic edema presentations including lymphedema and venous leg ulcers.^2,3 Therapeutic efficacy of compressive applications can be evaluated by defining interface pressure (IP) and IP distributions associated with specific textile combinations.² During compressive applications where an open wound is present, primary wound dressings should be used in combination with compressive wraps. Primary wound dressings …

Tandem Peptides Targeting Her2 For Delivery Of Cd44 Sirna Into Her2+ Breast Cancer Cells In Vitro, James Kalogeros

All Theses

More than 300,000 women will be diagnosed with breast cancer, and approximately 48,000 women will die this year due to the disease in the United States. HER2+ breast cancer accounts for 20-25% of invasive breast cancer, and it has a worse prognosis and higher early-stage mortality rate than other breast cancer subtypes. Common treatments for HER2+ breast cancer involve surgical removal of the breast or systemic therapy with chemotherapeutic drugs, both of which cause damage to healthy tissue. Due to the lack of a natural ligand for the HER2 receptor, there is a need for improved targeting strategies for the …

Laser Inscribed Graphene Aptasensor For Detection Of Apple Stem Pitting Virus, Yifan Tang

All Theses

Apple stem pitting virus (ASPV) is a latent RNA virus that could cause significant loss to apple production; early-stage field diagnosis could reduce the economic loss caused by ASPV infection. Biosensor is a promising user-friendly detection tool that could transduce biological or chemical interactions into electric signals. Among various types of biosensors, aptasensor, which use aptamers as recognition elements show potential as a high throughput, in-field test. The goal of this thesis is to develop an electrochemical aptasensor testing system for ASPV detection. The quality control study of laser inscribed graphene (LIG) based working electrode of the biosensor was conducted …

An In Vivo Biocompatibility Analysis Of A Novel Tissue Regeneration Matrix Using A Pig Model, Shamar Thomas

All Theses

The goal of this project is to develop an injectable bead scaffold to promote tissue regeneration in the void created by lumpectomy and to alleviate post lumpectomy problems by preventing local recurrence and minimizing surgical-related infections. Microbeads were synthesized from collagen type I and crosslinked with tannic acid to form the basis for this injectable therapeutic. Tannic acid acts as a therapeutic anticancer agent. The action mechanisms of tannins in breast cancer cells have been studied with studies showing tannins to be cytotoxic to cancer cells in a dose-dependent manner. Tannic acid induces apoptosis in breast cancer cells via caspase …

Soft Robotic Arms For Fall Mitigation: Design, Control And Evaluation, Param Malhotra

All Theses

Most fall mitigation devices present a heavy system that avoid injuries to the user by preventing the impact of a fall. They are dependent on the user capability or on the probability that the user falls in the assumed manner the system was designed for. Often that is not the case, hence this project initiates a novel concept of using soft robotic arms to prevent falls from happening in the first place itself and save the user from any injuries. This thesis describes the prototype and development of a soft continuum robotic backpack system. The system can validate its use …

Characterization Of Thermal Gelation Properties In Bioresorbable Thermally Activated Hydrogel Polymers For Hernia Surgery Applications, Alexander Mayfield

All Theses

Hydrogel adhesives are a new class of materials with excellent biocompatibility, which makes them very attractive for biomaterial applications. It has been previously shown that Tetronic T1107, a four-arm poly (propylene oxide)-poly (ethylene oxide) (PPO-PEO) block copolymer, is useful as a chemical crosslinking thermo-responsive hydrogel for bioadhesive applications. The end groups of this polymer are modified with acrylate and N-hydroxysuccinimide (NHS) functional groups. The acrylate end group gives the polymer cohesive properties with long-range chemical crosslinking using dithiothreitol (DTT), while the NHS end group gives the polymer adhesive properties through bonding with amines found in organic tissue. It was found …

Tissue-Engineered Living Pulmonary Valve For Young Adult Patients, Erica Hoskins

All Theses

Cardiovascular disease (CVD) is a non-communicable disease responsible for 659,000 deaths annually in the United States. While CVD can affect all components of the cardiovascular system, heart valve disease is responsible for 25,000 deaths yearly. Of specific interest is the pulmonary valve since there is limited research on resolving pathologies that affect it. Like the aortic and mitral valves, common pathologies include stenosis, regurgitation, and atresia. Notably, the pulmonary valve requires repair and replacement in pediatric patients and young adults due to congenital disabilities. Even with technological advances in valve replacements, limitations still present themselves for use with younger patients …

A 3d Tissue Engineering Model To Study Mitral Valve Annulus Calcification Under Diabetic Conditions, Erin James

All Theses

The most complex heart valve is the mitral valve (MV). Many pathologies can affect the MV, including stenosis, regurgitation, prolapse, and mitral annulus calcification (MAC). MAC is chronic degeneration of the annulus, which is the fibrous, saddle-shaped “ring” that can contract and relax with the myocardium. The prevalence of MAC is around 15% but increases in patients with other cardiovascular diseases and risk factors. It is also thought to increase in patients with type 2 diabetes, but MAC has not been properly characterized within this population because of confounding factors such as cardiac disease and kidney disease. The goal of …

Optimizing Crispr/Cas9-Mediated Knockdown Of Angptl3 In Liver Cell Lines And Mouse Hepatocytes, Meredith Reeves

All Theses

Familial hypercholesterolemia (FH) is a genetic condition characterized by elevated levels of low-density lipoprotein cholesterol (LDL-C) that leads to an increased risk of developing cardiac disease early in life (Shah et al., 2020). Current treatments such as statins and PCSK9 inhibitors have helped lower LDL-C levels, however they require repeated administration every 4-6 weeks to remain effective (Raal et al., 2018). Angiopoietin-like 3 (ANGPTL3) is an inhibitor of plasma lipid metabolism that has become a promising molecular target for the treatment of FH. Individuals with non-functional copies of ANGPTL3 demonstrate low levels of plasma LDL-C and triglycerides, indicating a protective …

Variations In Surgeon-Applied Loads During Passive Range Of Motion Following Total Knee Replacement With Relevance To Computational Modeling, Cj Bakle Ii

All Theses

Total knee replacement (TKR) is generally considered a successful treatment for musculoskeletal disorders of the knee. However, as many as 20% of patients report some dissatisfaction in their physical function after TKR. And approximately 50% of early revisions needed to address conditions related to component alignment and soft tissue tension to stabilize the knee. During TKR, surgeons manually perform passive range of motion (ROM) assessments to gain feedback perceived as tension in ligaments and other soft tissues. Such assessments are highly subjective and rely on the surgeon's perception of soft tissue tension rather than quantitative objective means. The variability in …

Nonlinear Optical Microscopy Assessment Of Tissue Structure And Chondrocyte Viability Of Articular Cartilage, Michael Le

All Theses

Articular cartilage functions to protect the ends of bones by providing a surface that can withstand compressive forces and minimize friction during movement. Collagen fibers form the organizational backbone of the extracellular matrix (ECM) in cartilage. Proteoglycans within the ECM function to retain water and provide the tissue with the swelling pressure needed to withstand compressional forces. Chondrocytes, the only type of cell found in articular cartilage, produces these collagen fibers and proteoglycans to maintain the tissue structure and function. Significant injuries to articular cartilage can damage the chondrocytes and disrupt their ability to maintain homeostasis in the tissue. Therefore, …

Insect Antennae As Bioinspirational Superstrong Fiber-Based Microfluidics, Griffin J. Donley

All Theses

Nature is frequently turned to for inspiration for the creation of new materials. Insect antennae are hollow, blood-filled fibers with complex shape, and are cantilevered at the head. The antenna is muscle-free, but the insect can controllably flex, twist, and maneuver it laterally. To explain this behavior, a comparative study of structural and tensile properties of the antennae of Periplaneta americana (American cockroach), Manduca sexta (Carolina hawkmoth), and Vanessa cardui (painted lady butterfly) was performed. These antennae demonstrate a range of distinguishable tensile properties, responding either as brittle fibers (Manduca sexta) or strain-adaptive fibers that stiffen when stretched (Vanessa cardui …

Quantifying Shear Stresses In Tissue Engineered Aortic Heart Valves, Raj Nitin Dave

All Theses

Present heart valve prosthesis have limitations such as capability to grow, repair and remodel post implantation. Tissue engineering offers to be a promising alternative to overcome these limitations. Maturation of seeded human cells on the valve subjected to favorable growth conditions in the bioreactor is critical to the success of tissue engineered heart valves. Mechanical stress and strain which results from the pressure and flow conditions in the bioreactor plays a critical role on the developing valve tissue and are currently unknown. The goal of this research is to relate the magnitude of wall shear stress (WSS) within the heart …

Fabrication Of Hydrogel Microparticles For Acute Treatment Of Penetrating Brain Injuries, Isabell Foulger

All Theses

Traumatic brain injuries (TBIs) are a type of acquired head trauma that results from an external force to the head. The development and severity of the secondary injury increases the risk of neurodegeneration and reduced cognitive recovery. Glucocorticoids are potent antiinflammatory therapeutics that have been investigated for potential treatment of TBIs, strokes, and other neuroinflammatory pathologies. However, their clinical application has been limited due to their ability to induce a variety of side effects, including adrenal suppression, edema, and reduced plasticity of the hippocampus. The use of a localized drug delivery system would overcome these systemic concerns. In previous studies, …

Toward Sustainable Urban Food Production: Integrating Hydroponic Cultivation With Wastewater Reuse, Amanda Tan

All Theses

The growing crisis of freshwater scarcity together with the increasing global food demand directs attention to the need for alternative water sources for agriculture. The research presented here engages this need by carrying out indoor cultivation of food crops in Nutrient Film Technique (NFT) hydroponic systems using residential wastewater. Randomized single factor experimental designs were used to investigate the physiochemical and microbiological makeup of the hydroponic nutrient solution throughout the cultivation cycle and their relationship with different plant development parameters.

For agricultural wastewater reuse to be of low risk to human health there must be some advancement in pathogen monitoring …

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 …

Portable U-Bent Optical Fiber Biosensor For Detecting Microcystin-Lr, Quan Dio Anh Le

All Theses

Cyanobacteria are the only known prokaryotes that can photosynthesize. Due to their unique ability, they are important entities in the global carbon and nitrogen cycles. However, two factors can turn cyanobacteria into a nuisance. In general, eutrophication is the process that supplies external nutrients that are needed for cyanobacteria blooms into bodies of water from the surrounding environment. Climate warming intensifies this process by producing carbon dioxide, methane, and nitrous oxide. With cyanobacteria blooms occurring worldwide, they are becoming a bigger threat to human health, and there has been increased interest in detecting cyanobacteria and their toxic byproducts.

For instance, …

Investigation On Effects Of Lactate Adaptation Using Metabolic Indicators And Amino Acids To Explore Cell Metabolism, Lisa Uy

All Theses

Biopharmaceutical products are drugs that are made from living cells. One protein type of high importance to biopharmaceuticals is monoclonal antibodies. Monoclonal antibodies allow for highly specific, targeted treatment of diseases and detection of molecules related to diseases. With major roles in detecting and/or treating diseases like human immunodeficiency virus (HIV), coronavirus disease 2019 (COVID-19), and some cancers, monoclonal antibodies are in demand. This demand has led to a need for efficient cell culture systems to produce high yields of protein with minimal waste. The most commonly used cell culture system for these high-value proteins is Chinese hamster ovary (CHO) …

A Comparison Of Methods To Measure Crop Water Use In South Carolina, Andrew C. Ewing

All Theses

The objective of this thesis was to compare cost-effective methods of measuring crop water use, known as evapotranspiration (ET), in South Carolina’s humid climate. The methods analyzed were the surface renewal method (SR), the Eddy Covariance method (EC), large in-field weighing lysimeters, a newly developed pressure differential device (PDD), a Class A Evaporation pan, and the Penman-Monteith equation. In the first chapter, ET measurements obtained by SR were compared to ET measured by EC and weighing lysimeters. For reference, EC and SR track the energy budget to estimate ET, while the weighing lysimeters used in this study are box-like containers …

Mechanical Analysis Of Double Network Hydrogels To Determine Suitability As An Articular Cartilage Substitute, Casey Virginia Young

All Theses

The Center for Disease Control has found that between 2013-2015, 26% of women and 19% of men reported doctor-diagnosed cartilage disease or damage. Currently, there exists a substantial population with cartilage damage or disease needing a solution to increasing pain and decreasing function and mobility. Many of these individuals are young and thus looking for a treatment to delay a total knee replacement. Many others are elderly and thus looking to avoid major surgeries, as the riskiness of these procedures increases with age. As researchers look towards a method of cartilage replacement, hydrogels show measurable potential as a synthetic substitute …

Regeneration Of The Ventricular Endocardium Within Acellular Whole Rabbit Hearts Using A Layer-By-Layer Seeding Method, Clayton Lewis Compton

All Theses

In the United States, 1 out of every 9 death certificates in 2013 referenced heart failure.1 Despite the outstanding need of treatment options for heart failure, heart transplantation remains the optimal treatment method. However, there is a severe shortage of donor hearts available for transplantation.2 Other available treatment options are not ideal because they do not fully restore function and are associated with creating other complications.3 Thus, there is a need for developing a living tissue engineered whole heart for transplantation to provide an alternative option for patients on the waitlist to receive a donor heart.

Our solution is to …

The Effect Of Surface Roughness Modifications And Chitosan Surface Coatings On Biofilm Formation For Prevention Of Orthopaedic Infections, Nathan Dewayne Smith

All Theses

Infections have been reported to occur in up to 91% of patients after orthopaedic procedures. Many of these infections are caused by bacterial biofilm growth on the surface of the implanted device. Surface modifications of fracture fixation implants have been taken into consideration in order to reduce infection rates and improve clinical results in orthopaedic procedures. Effective surface treatments will also reduce the need for antibiotics and prevent formation of drug-resistant bacteria. Titanium alloy sample discs (N=144) were prepared with six surface roughness treatments through polishing as well as with four different concentrations of chitosan through spin coating. In vitro …

Development And Initial Validation Of A Surgical Instrument For In Situ Mechanical Characterization Of Surgical Mesh-Tissue Composites, Jorge Ivan Hernandez Sanchez

All Theses

Approximately 5 million Americans have an abdominal wall hernia, and over 700,000 undergo surgical procedures every year to treat them. Surgical procedures have evolved with the goal of preventing recurrences, leading to the current gold standard of treatment: hernia repair with mesh. Hernia repair with mesh consists on augmenting the weakened abdominal wall by implanting a synthetic or biological mesh. Although the adoption of hernia repair with mesh has improved outcomes, recurrence from primary repair procedures with large incisions (>10 cm) remains an alarming 32%.

The wide variety of implanted surgical mesh (materials, structure) and surgical variability (attachment method, …

Autologous Protein Solution Exhibits Potential To Mitigate Osteoarthritis (Oa) Progression In A Human Explant Co-Culture Model, Kathleen Emily Steckbeck

All Theses

Osteoarthritis (OA) is a debilitating and painful disease that affects upwards of one in every eight adults1,2. OA influences the entire joint, but is traditionally characterized by cartilage degradation3. OA is a multifactorial disease with genetic, biological, and biochemical consideration, but there has been a recent shift in scientific opinion that the pathological progression of OA stems from an inflammatory milieu produced by the feed-forward progressive pathway as evidenced by simultaneous cartilage and synovium co-culture4–7. Autologous protein solution (APS) poses as an intriguing potential OA therapy by possessing a high anti-inflammatory and anabolic mediator concentration profile that could potentially mitigate …

Fabrication And Characterization Of An Extracellular Matrix Hydrogel For Aortic Valve Applications, Brady Culbreth

All Theses

With an estimated 5 million people suffering from valve disease in the United, valve disease is currently the leading cause of cardiovascular disease. Each year, between 80,000 and 85,000 aortic valve replacements are performed in order to treat the stenotic heart valves. Despite this being a worldwide epidemic, the current valve replacement options that are on the market have distinct limitations. Furthermore, a viable alternative does not exist for the patients that are not candidates for the current treatment methods. Our proposed solution to this epidemic is to create a highly viable injectable scaffold that would allow for the minimally …

Analysis Of Citrate Content In Bone Using High Performance Liquid Chromatography, Matthew Konstantin Pysh

All Theses

Approximately 1.5 wt. % of bone is comprised of citrate molecules bound to the surface of apatite crystals. Furthermore, 80 to 90% of physiological citrate is contained within bone. Recently, interest in citrate has increased due to the potential of a citrate based method for estimation of postmortem intervals, time since death, of skeletal remains. The broad objective of this research was to develop and validate a High-Performance Liquid Chromatography (HPLC) method for quantitative and qualitative analysis of citrate in bone. An appropriate HPLC column and operating conditions for the detection of citrate were selected and subsequently used to analyze …

Decellularized Bovine Nucleus Pulposus As A Biomimetic Scaffold For Intervertebral Disc Regeneration, Christopher Fernandez

All Theses

Low back pain (LBP) is a significant burden with a lifetime prevalence of 84% and estimated expenditures of $85.9 billion.[1,2] Although LBP is multifactorial; it has been shown that LBP can originate from degenerating intervertebral discs (IVDs); a process which initiates in the nucleus pulposus (NP); a hydrated tissue primarily composed of type 2 collagen and proteoglycan. Current therapies for IVD degeneration (IDD) are palliative and merely delay surgical management. While these procedures may relieve pain temporarily, they fail to address the underlying cause of degeneration and make no attempt to regenerate the effected tissue. Additional concerns with the use …

Endothelialization Using Protein Substrates And Hydrogels For Aortic Valve Applications, Elizabeth A. Fontaine

All Theses

Aortic valve disease is currently the leading cause of cardiovascular morbidity in the United States.1 In 2003, approximately 290,000 patients required heart valve replacement and that number is estimated to continue to rise as the average age of the population continues to increase.2 However, the current valve replacement options have multiple limitations. Tissue engineering hopes to address these shortcomings by providing a viable valve that more closely mimics the native valve, structurally and functionally.3 An ideal valve replacement should contain endothelial and interstitial cells, with the ability to remodel the extra-cellular matrix. While tissue-engineered heart valves are not uncommon in …

Assessment Of Bore-Cone Taper Junctions In Explanted Modular Total Hip Replacements, Christine Margaret Stamer

All Theses

For people with chronic hip pain due to arthritis or other conditions, a total hip replacement (THR) is a common procedure used to eliminate the pain. Due to the natural variation in patient anatomy, THR prostheses are becoming increasingly more modular to allow for a more customized initial replacement and for an easier revision if needed in the future. Currently, THR prostheses routinely have modular femoral heads to provide surgeons with intraoperative flexibility. This modularity allows the surgeons to maintain the proper leg length and restore hip biomechanics for the patient and insert the components more easily and precisely. Modular …

Development Of Poly(Lactic Acid)-Poly(Ethylene Glycol) Nanoparticles For The Delivery Of Non- Toxic Drug In Combination Therapy For The Treatment Of Glioblastoma And Neuroblastoma, Olivia Grace Decroes

All Theses

Glioblastoma and neuroblastoma are both solid-form tumors. Glioblastomas primarily reside in the brain, while neuroblastomas are found in the sympathetic nervous system. Both glioblastoma and neuroblastoma re classified as orphan diseases, which affect less than 200,000 individuals a year. Over the course of 5 years, 40% of patients diagnosed with neuroblastomas and only 6% of patients diagnosed will glioblastomas will be living.^73,74. Glioblastoma and neuroblastoma tumors possess a gene known as MGMT. MGMT is used by tumors as a DNA repair mechanism, which increases the likelihood these tumors will become resistant to traditional drug therapies.^28,37 Other pathways, …