Biomedical Engineering and Bioengineering Commons^™

Analysis Of The Mechanical, Microstructural, And Biocompatibility Properties Of Novel Magnesium-Based Hybrid Nanocomposite Materials For Orthopedic Applications, Thomas H. Mcgehee

Biomedical Engineering Undergraduate Honors Theses

Bone fractures and complete joint replacements are becoming more common, primarily because of accidents and age-related issues. Conventional solutions to treat these orthopedic injuries involve inert metal alloys to correct bone fractures until the healing process is complete, where a secondary revision surgery is then required to remove the implant. Issues regularly associated with these solutions include stress shielding, bone resorption, infection, inflammation, and implant loosening. Magnesium (Mg)-based nanocomposites offer promising potential as an alternative to commonly used metal alloys because of their favorable mechanical properties and biocompatibility. A particularly advantageous property of Mg is its natural biodegradation in vivo, …

Aerobic Biodegradation Of Algae-Derived Bioplastics Under Controlled Composting Conditions, Clayton J. Lords

All Graduate Theses and Dissertations, Fall 2023 to Present

Plastics are versatile polymers that have become critically important materials in many industries. Although plastics are important and useful materials, they account for vast amounts of environmental pollution and climate change contribution. Sustainable bioproducts are becoming increasingly important in the effort to mitigate the impacts of pollution and climate change. The scale of environmental damage caused by plastic pollution highlights the need to implement sustainably sourced biodegradable plastics within the global economy. Bioplastics are materials that may be manufactured from biological materials or can biodegrade under certain conditions. Algae are microorganisms that can be grown using nutrient-rich municipal wastewater; the …

Analyzing Microalgae-Bacteria Population Changes In Response To Environmental Parameters For Improved Wastewater Treatment, Amanda M. Moravek

All Graduate Theses and Dissertations, Fall 2023 to Present

Microalgae are incredible organisms that have a variety of uses such as wastewater treatment, fertilizer, livestock feed, and bio-compound production. Microalgae require a light source and minimal nutrients space to proliferate, making them an environmentally friendly and sustainable option for such processes. The Sustainable Wastes-to-Bioproducts Engineering Center at Utah State University is developing and implementing a Rotating Algae Biofilm Reactor (RABR) to remove total nitrogen and phosphorous from the Central Valley Wastewater Reclamation Facility wastewater effluent. Harmful compounds such as nitrates and phosphates are metabolized by the microalgae and converted into useful bioproducts, resulting in a circular economy. These RABRs …

Uv-A Light And Heat-Activated Antimicrobial And Biodegradable Materials For Food Packaging And Preservation, Michael J. Bodily

All Graduate Theses and Dissertations, Fall 2023 to Present

Current food packaging materials are often non-biodegradable and harmful for ingestion, which poses a threat to the environment and public health. Thus far, the dangers of microbial contamination of food on human health have outweighed the risks associated with using these conventional packaging plastics. A possible solution to these issues is to use a combination of innovative materials and microbial inactivation methods that can potentially both reduce plastic waste and combat harmful microorganisms. In this study, two antimicrobial, biodegradable composites were developed and tested for their ability to inactivate two types of bacterium, Escherichia coli K12 and Listeria innocua, …

Applying Residence Time Distribution Theory To Coronary Thermodilution Curves., Jacob Michael Miller

Electronic Theses and Dissertations

Cardiovascular diseases remain the leading cause of death worldwide and coronary microvascular dysfunction is one cardiovascular disease which is particularly challenging to diagnose and treat. Coronary thermodilution is a widely used, invasive procedure to evaluate microvascular function by generating physiological indices such as coronary flow reserve and the index of microvascular resistance. Although commonly cited as an indicator dilution method in the cardiovascular literature, current coronary thermodilution techniques lack rigorous application of the accompanying mathematical framework, thereby leaving potentially valuable diagnostic information unexploited. This study bridges that gap by demonstrating the equivalence between indicator-dilution theory and residence time distribution theory …

3d Bioprinting Of Hydrogel Scaffold Skin Equivalents For Cosmetic And Drug Testing, Allison Reno

All Dissertations

Tissue engineering scaffolds are a crucial element of generating larger 3D tissue equivalents for modeling and clinical grafting. Currently, much of scaffold technology has not been significantly updated since the introduction of manually pipetted hydrogels and electrospun fiber scaffolds. Both of these approaches have their advantages and disadvantages, but neither utilize emerging biofabrication techniques such as advanced 3D bioprinting and plotting. In addition to more precision in the outer geometries of the scaffold, the use of bioprinting also introduces the ability to shape hydrogels into very intricate porous inner patterns within the outer geometries. This allows for the design of …

Development Of Rolipram Loaded Pgp Nanoparticles For Spinal Cord Injury Repair, Zhen Liao

All Dissertations

Spinal cord injury (SCI) leads to devastating neurological deficits due to primary mechanical damage and secondary injury mechanisms, including inflammation, oxidative stress, excitotoxicity, and inhibitory scarring, which collectively impede neural regeneration. One key aspect of SCI pathology is a significant reduction in cyclic adenosine monophosphate (cAMP) levels, primarily due to increased phosphodiesterase (PDE 4) activity. As a ubiquitous second messenger, cAMP regulates key signaling pathways, including protein kinase A (PKA) / cAMP response element-binding protein (CREB) and exchange protein activated by cAMP 2 (EPAC2). Therefore, restoring/increasing cAMP level is one of the major therapeutic strategies to reduce neurotrauma and restore …

Development Of Translational Microscale Systems To Interrogate How Biophysical And Biochemical Cues Alter The Phenotype Of Hormone Positive Breast Cancer, Braulio Ortega Quesada

All Dissertations

Cancer is a complicated disease and one in every three diagnoses are women with breast cancer. Recent research shows that the progression of cancer depends strongly on interactions with other non-cancerous cells and non-cellular components. Metastasis, the spread of cancer to other parts of the body, is a key step in cancer progression and makes treatment harder, leading to poor response to treatments culminating in death in ~90% of patients. This dissertation focused on creating a series of microdevices as novel pre-clinical models of breast cancer. Two different devices were fabricated to (1) study how exposing cancer cells to the …

Toward The Application Of Natural Language Processing In Electronic Health Record Analysis For Taxonomy Development, Latoya Mcdonald

All Dissertations

Electronic health records (EHRs) are pivotal resources for nurse practice because they increase the timeliness and reliability of patient information at the point of care and support access by multiple healthcare providers and the individual patients themselves. However, it is widely recognized that data extraction from EHRs is challenging due to the variability in the language used in clinical care notes and the lack of standardized terminology across healthcare systems. The broad objective of this dissertation is to develop taxonomy-based classification models for nursing care by applying feature engineering approaches to EHRs that include nursing care of ostomy patients following …

Ex Vivo Multiplex Knockdown Of Angptl3 And Cypor In Hepatocytes As A Novel Cell Therapy For Familial Hypercholesterolemia, Callie D. Clark

All Dissertations

Inherited metabolic diseases (IMDs) affect approximately 1 in 800 individuals. The only curative treatment for IMDs is liver transplantation. However, transplantation carries significant risks, including organ rejection and a lifelong need for immunosuppression. Therefore, gene editing has emerged as a promising alternative to liver transplantation for treating IMDs.

Familial hypercholesterolemia (FH) is and IMD characterized by elevated LDL-C levels resulting in premature cardiovascular disease. CRISPR-Cas9-mediated gene editing to disrupt the gene encoding angiopoietin-like 3 (ANGPTL3) in the liver represents a novel therapeutic approach for FH. Nonviral delivery performed ex vivo is safer than systemic delivery because gene editing is in …

Identifying Novel Molecular Targets To Induce Ferroptosis In Drug-Tolerant Cancer Cells Through Computational Modeling, Haris J. Rana

Biological Sciences Undergraduate Honors Theses

Ferroptosis is an iron-dependent, reactive oxygen species (ROS)-driven form of regulated cell death in which the cell membrane is degraded by lipid peroxidation. It is regulated by multiple enzymes, such as glutathione peroxidase 4 (GPX4), which prevents membrane degradation by reducing lipid peroxides and protecting cells from oxidative damage. When inhibitors like RSL3 target GPX4, lipid peroxides build up, and toxic ROS compromises membrane integrity. Traditional anticancer treatments, such as most chemotherapies, aim to eliminate tumor cells by damaging DNA and triggering apoptosis. However, resistance to apoptosis is a “hallmark of cancer,” often resulting in treatment failure. As a distinct …

Localized Intraarterial Drug Delivery Device, Max P. Green

Biomedical Engineering Undergraduate Honors Theses

Stroke is a prevalent and deadly disorder that causes significant human and economic loss each year. Treatment of stroke is largely done through two routes: intravenous thrombolytic therapy and mechanical thrombectomy. This paper considered a design for a device that combines these two approaches. The device aims to use localized delivery of a thrombolytic agent to a clot site to treat stroke clots. An iterative approach to design was taken to continue to refine device designs generated by previous work. Components, including a balloon for localization, a semi-porous membrane for drug dispersion, and combinations were tested in scaled-up form. Generalizations …

Examining The Effects Of Quercetin On Phenotypic Characteristics Of Human Mesenchymal Stem Cells, Thomas M. Needy

Biomedical Engineering Undergraduate Honors Theses

Introduction A significant obstacle to mesenchymal stem cell (MSC) potency and therapeutic utility is in vitro senescence, an irreversible cessation of replication associated with age-related complications. Senolytic drugs, such as quercetin, may be helpful in selectively culling senescent cells while leaving non-senescent cells unaffected, thereby increasing potency of high-passage MSCs.

Methods The phenotypic, genotypic, and immunomodulatory effects of quercetin were assessed using in vitro models. Senescent cells, created through repeated subculturing of MSCs in vitro, and non-senescent cells were treated with 10 μM quercetin, differentiated into osteocytes, adipocytes, and chondrocytes, and analyzed to observe the effect of quercetin.

Results Quercetin …

The Effect Of A Peptide Targeting Ligand On Transfection Efficiency Of Polymeric Nanoparticles To Dendritic Cells, Anthony Radka

Honors Theses

Autoimmune diseases affect approximately 5-8% of the global population, leading to chronic symptoms, long-term treatment, and reduced quality of life. Current therapies primarily rely on lifelong administration of immunosuppressants, which are associated with severe side effects and heightened susceptibility to infections. This has spurred interest in cellular therapies that manipulate dendritic cells (DCs) effectively and can selectively treat these diseases. This work aims to improve the efficacy of dendritic cell-based therapies using cationic polymers that can electrostatically complex with nucleic acids, forming nanoparticles referred to as polyplexes, that can deliver therapeutic nucleic acid cargo. These particles are a favorable alternative …

Automated Identification Of Clinically Meaningful Biomechanical Phenotypes In Cerebral Palsy Through Multicenter Gait Data, Adam Graf, Joseph Krzak, Karen M. Kruger, Jon Davids, Ryan Smith, Brandon Steinlein, Anita Bagley

Biomedical Engineering Faculty Research and Publications

Background

Cerebral palsy is the most prevalent motor disability in childhood, encompassing various movement disorders that affect walking. Researchers have described gait patterns in cerebral palsy, but these are often subjective and based on clinician experience. This study introduces an automated approach to objectively identify clinically meaningful biomechanical phenotypes in cerebral palsy and test it on multicenter gait data. Utilizing instrumented gait analysis, this research aims to improve treatment strategies for gait dysfunction. This study addresses whether classification algorithms can objectively identify clinically meaningful gait patterns and if severe gait deviations are more frequent in advanced forms of cerebral palsy. …

Influence Of Boundary Conditions And Blood Rheology On Indices Of Wall Shear Stress From Ivus-Based Patient-Specific Stented Coronary Artery Simulations, R. Patrick Mccarthy, Peter J. Mason, David S. Marks, John F. Ladisa Jr.

Biomedical Engineering Faculty Research and Publications

The long-term clinical efficacy of coronary stents is limited by restenosis. Coronary stenting results in altered arterial geometry, local blood flow patterns, and wall shear stress (WSS), all of which can influence restenosis. Computational fluid dynamics (CFD) simulations employ assumptions about blood properties and boundary conditions, which also influence WSS alterations from stenting. Our objective was to evaluate three common assumptions applied with stented coronary artery CFD simulations (inlet velocity profile, outlet boundary conditions, and viscosity) to provide insight for future studies. A patient-specific right coronary artery was reconstructed from intravascular ultrasound and computed tomography imaging. Time-averaged WSS (TAWSS) and …

Efficacy Of Mitophagy Inhibition As A Potentiating Agent For Conventional Chemotherapy, Morghan Relich, Shelby Bess

Biomedical Engineering Undergraduate Honors Theses

Cancer is a result of uncontrolled growth and reproduction of cells. Damaged or abnormal cells grow and multiply when they should not and in turn the cells continue to proliferate and metastasize. Malignant cells rely on functional mitochondria for proliferation, metastasis, and survival. These mitochondria maintain a functional mitochondrial network through a quality control mechanism called mitophagy. Mitophagy is a conserved intracellular process to maintain quality control and remove damaged mitochondria.

Previous research has been done to examine the effects of mitophagy in tumor cells, as well as the effects of mitophagy inhibition. One focus of current research has been …

Metabolic Responses Of Adipose-Derived Stem Cells In Collagen I Hydrogels, Caroline R. King

Biological Sciences Undergraduate Honors Theses

Peripheral nerve injury affects approximately 44 in 1 million people in the United States every year and can lead to incomplete nerve recovery and loss of motor and sensory function. A significant amount of energy is required for nerve injury repair. A lack of energy allocation to the injury site hinders repair. Current treatments include hollow nerve guidance conduits, decellularized nerve grafts, and autografts. However, they are limited by factors such as donor site morbidity and sustained immunosuppressive treatments. Using three-dimensional collagen I hydrogels laden with adipose-derived stem cells (ASCs) can assist in neural regeneration. Three-dimensional collagen scaffolds aim to …

Deciphering And Translating Bioinspired Structures For Engineering Materials Design Via Computational Modeling And Machine Learning, Zhangke Yang

All Dissertations

Nature has evolved extraordinary structural materials—such as nacre, bone, and the mantis shrimp’s dactyl club—that achieve remarkable combinations of strength, toughness, and impact resistance. These properties arise from sophisticated synergies between structure and composition. Inspired by these biological systems, this dissertation presents a comprehensive investigation into bioinspired materials, uncovering fundamental mechanisms and providing guidance on designing materials with superior mechanical properties.

This dissertation begins by examining the "brick-and-mortar" structure of nacre, which informs the design of layered polymer-graphene nanocomposite films. Using coarse-grained molecular dynamics simulations, I elucidate mechanisms of dynamic wave propagation and energy dissipation in these systems, providing critical …

Gene Mutation And Chemotherapy Response In Azoxymethane Induced Colorectal Tumors, Maya M. Vance

Biomedical Engineering Undergraduate Honors Theses

Colorectal cancer research is a field of increasing importance as disease prevalence continues to increase over time. In looking at the origin of the disease, a driver gene known as p53 is of particular interest for its role in the stimulation of the mutated Wnt pathway. Developing as a missense-type mutation, this gene that ordinarily functions as a tumor suppressor is investigated as a gene of interest for tumor development. In this study, a mouse model was used to examine the development of colorectal cancer with a total of n=34 samples, including n=9 tumors and n=25 colons. The concentration of …

Optimizing The Effects Of Yoda1 And Assessing The Effects Of Mrna Silencing Of Piezo1 Gene In Mesenchymal Stem Cells, Addison R. Mclaughlin

Biomedical Engineering Undergraduate Honors Theses

Mesenchymal stem cells (MSCs) are multipotent adult stem cells that are capable of differentiating into various skeletal tissues, making them promising candidates for regenerative medicine. A critical factor influencing their differentiation potential is mechanosensitivity, the ability to respond to mechanical stimuli. The mechanosensitive calcium ion channel PIEZO1 has emerged as a key regulator in this process, particularly in osteogenic differentiation. This study investigated the role of PIEZO1 in MSC osteogenesis through pharmacological activation using YODA1 and gene silencing via siRNA. Human bone marrow-derived MSCs were cultured and induced for osteogenic differentiation under varying concentrations and durations of YODA1 treatment. Alizarin …

Fabrication And In Vitro Biocompatibility Assessment Of Composite-Coated Magnesium Materials, Bryce Williams

Biomedical Engineering Undergraduate Honors Theses

This study provides a comparative assessment of the corrosion, morphology, and biological properties of four of the most promising coating methods for magnesium in biomedical applications, namely micro-arc oxidation (MAO), graphene oxide (GO)-containing MAO coating, MAO/sol-gel composite coating, and MAO/polycaprolactone (PCL) polymer dip coating approaches. Despite the abundance of research focused on these promising approaches, there is a notable lack of comparative studies evaluating their properties. To this end, the investigated composite coatings are ZK60+MAO, ZK60+MAO/GO, ZK60+MAO/Sol-gel, and ZK60+MAO/PCL composite coating. Several tests were used to assess various properties of the prepared groups such as in vitro corrosion characteristics, surface …

Insert Creation To Mimic Blood Vessels In Gel Phantoms, Courtney Bloom

Biomedical Engineering Undergraduate Honors Theses

Gel phantoms are commonly used in research settings due to their ability to mimic soft tissue. Creating these phantoms usually involves 3D printing an insert, embedding it in gel, and then washing the insert out. Polyvinyl alcohol (PVA) is typically used as the insert material, but it often swells and deforms the gel during the washout process. Aquapour, a water-soluble material, was investigated as a potential replacement for PVA. Unlike PVA, Aquapour comes in a powdered form that can be mixed with water to create a castable slurry. To create molds to cast Aquapour, SolidWorks was used to design two …

Mechanistic Investigation Of Ring-Opening Polymerization Of Polycaprolactone Using Tin(Ii) Catalysts: Ligand Effects And Biomedical Applications, Eva-Larue M. Barber

Honors Scholar Theses

This research explores the mechanistic aspects of ring-opening polymerization (ROP) of ε-caprolactone (CL) to produce polycaprolactone (PCL), a biodegradable polymer widely used in biomedical applications. The study investigates how light exposure and catalyst concentration influence polymerization efficiency, using tin(II) 2-ethylhexanoate [Sn(Oct)₂] as the catalyst in a non-polar toluene solvent at 90 °C. Reactions were conducted under either ambient light or black light bulb (BLB) illumination, with monomer-to-catalyst ratios of 1:1 and 200:1.

Proton nuclear magnetic resonance (¹H NMR) spectroscopy was used to analyze conversion efficiency by tracking the disappearance of monomer signals and appearance of characteristic PCL peaks. Results revealed …

Synthesis And Characterization Of Composite Hydrogels For Tissue Engineering: An Investigation On Mechanical Properties And Biocompatibility, Ismael Lamas Jr.

Theses and Dissertations

This study investigates the fabrication and characterization of Polyvinyl Alcohol (PVA)/agar double-network (DN) hydrogels for biomedical applications, focusing on mechanical strength, biocompatibility, and tissue engineering potential. Techniques like swelling ratio analysis and Fourier-transform infrared spectroscopy (FTIR), alongside antibacterial and cytotoxicity assays, were employed to evaluate the hydrogels' properties. Results show that increasing agar content enhances mechanical and physical properties, with swelling ratios increasing by 300% when agar makes up 6% of the hydrogel, compared to 140% without agar. A positive correlation was observed between agar concentration and compressive and tensile moduli. Load-relaxation rates, essential for viscoelastic properties, also improved with …

Impact Of Shear Flow On Marine Biofilms Using Hyperspectral Imaging, Shantanu Mahesh Kore

All Theses

Various microbial communities in marine biofilms cause biofouling on submerged surfaces, posing challenges to marine industries. Despite their ecological and economic importance, biofilms' biomechanical and biochemical responses to hydrodynamic shear stress are insufficiently understood, particularly in dynamic flow conditions. To fill this gap, our study uses an innovative fiber-optic hyperspectral imaging (HSI) system and a supercontinuum laser source to examine marine biofilms' structure, composition, and detachment behavior at different shear stress levels.

To detect spectral and spatial heterogeneity in live biofilms without labeling, we created a custom imaging pipeline that captures reflectance spectra in the 600-850 nm range, targeting microbial …

Gene Editing Combined With Apap Diet-Mediated Selection In A Ldlr-/- Mouse Model Of Familial Hypercholesterolemia, Pramita Suresh

All Theses

Cell-based gene therapy has garnered significant interest in treating familial hypercholesterolemia (FH), an autosomal co-dominant disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) levels. However, achieving a therapeutic threshold level of engraftment of gene-modified cells is a significant hurdle. In FH, as in most liver diseases, the transplantation of healthy gene-modified hepatocytes does not result in a selective advantage for the healthy hepatocytes over native hepatocytes for clonal expansion in the liver. In FH, as in most liver diseases, the transplantation of healthy gene-modified hepatocytes does not provide a selective advantage for the healthy hepatocytes over native hepatocytes regarding clonal …

Exploring Veto Activity: Dnam-1-Cd155 Axis In Overcoming Nk Cell-Mediated Allo-Rejection And Applications For Car-T Cell Therapy, Wei-Hsin Liu

Dissertations and Theses (Open Access)

As Miller et al. defined veto activity, it enables cells to target host cytotoxic T lymphocyte (CTL) precursors specific to veto cells' antigens, selectively eliminating anti- donor T cell clones without inducing rejection. By leveraging this unique immune property, two key research aims were proposed: “Exploration of the Impact of Veto Activity on Natural Killer (NK) Cell-Mediated Allo-rejection” and “Development of Off-the- shelf Chimeric Antigen Receptor (CAR)-T Therapy: Engineering Anti-Viral Veto CD8+ T Cells”. As demonstrated in our previous research, in a murine model with mild conditioning, anti-third-party central memory CD8+ veto T cells (veto Tcm) can prevent T cell- …

Blink-Related Brainwaves As Digital Biomarkers For Cognition Assessment During Complex Tasks, Lexine Carmlixa Sibert-Jolissaint

Theses and Dissertations

Blink-related oscillations (BROs) are neurophysiological responses observed in electroencephalography (EEG) following spontaneous blinking, reflecting the brain processing of new visual information. Prior research has demonstrated BRO responses across various cognitive states, such as resting, cognitive loading, and sensory stimulation, highlighting their potential as a non-invasive biomarker of brain function. We conducted the first investigation of BRO responses during a verbal fluency (VF) task, which is a complex, dynamic task state combining memory, visual perception, executive function, and language processing. Using publicly available EEG data from 22 healthy adults, we measured BRO responses over the left anterior frontal region corresponding to …

Effectiveness Of Virtual Reality Rehabilitation For Cervical Spinal Cord Injury: A Systematic Review And Meta-Analysis, Viprav B. Raju, Brian D. Schmit, Aditya Vedantam

Biomedical Engineering Faculty Research and Publications

This systematic review and meta-analysis evaluated the effectiveness of virtual reality (VR) rehabilitation in improving functional performance for patients with cervical spinal cord injury (CSCI), which affects both upper and lower limb function. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, electronic databases including PubMed, Medline, Embase, Scopus, and Cochrane Library were searched. Meta-analysis was conducted on studies reporting common functional outcomes, with standardized mean difference (SMD) used to quantify effect sizes. Nine studies were included in the systematic review, and seven were analyzed in the meta-analysis. Three studies focused on upper limb outcomes, and six …