Biomedical Engineering and Bioengineering Commons^™

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 …

Using Deep Learning And Two-Photon Excitation Fluorescence Microscopy To Predict Breast Cancer Recurrence And Response To Chemotherapy, Nicholas Powell

Graduate Theses and Dissertations

Accurate prediction of breast cancer recurrence plays a critical role in guiding treatment decisions, particularly regarding the use of systemic therapy for patients. While genomic assays such as the Oncotype DX Recurrence Score offer valuable prognostic information, they are limited in accessibility and application. The work presented in this thesis explores an imaging-based approach for the prediction of breast cancer recurrence that combines multiphoton microscopy (MPM) with deep learning to classify individual breast cancer biopsy samples by risk of recurrence. Genomic differences in tumors with different recurrence potentials may translate to distinct optical and structural information that can be captured …

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 …

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 …

Personalized Model Of Cardiac Fibroblast Signaling Using Patient-Specific Data, Elizabeth A. Schuler

Chemical Engineering Undergraduate Honors Theses

Heart disease is the leading cause of death worldwide for both men and women, and cardiac fibroblasts are critical to heart form and function. Essential roles of cardiac fibroblasts include cell-cell communication, cell-cell signaling, and synthesizing and degrading the extracellular matrix (ECM), which controls structural support and tissue repair of the heart. Abnormal fibroblast signaling can lead to negative impacts, including fibrosis, impaired heart function, and inflammation. A computational model of cardiac fibroblast signaling on Netflux and MATLAB software was adapted and utilized to determine the effect of patient-specific levels of cytokines, hormones, growth factors, peptides, and membrane tension on …

Design And Evaluation Of Antibody-Conjugated Microneedle Patch For Early Mrsa Biomarker Detection, Kylee Marie Pop, Alexis Richie, Nicholas Jenkins, Andrew Holmes

Honors Theses

Post-operative orthopedic surgical site infections (SSIs), specifically those caused by methicillin resistant Staphylococcus aureus (MRSA), present a significant clinical challenge due to delayed detection, increased morbidity, and current rising healthcare costs. Early detection of infection remains limited due to the current methods of diagnosis, which consist of observation of the surgical site and laboratory infrastructure for conformation of infection. To combat these issues, my team and I have designed and evaluated a minimally invasive microneedle diagnostic patch that continuously monitors for the presence of MRSA-associated biomarker PBP2a in interstitial fluids around surgical site incisions. Upon antigen detection, a colorimetric response …

Computationally Guided Liquid Crystal-Based Competitive Binding Sensing Platform For Optical Detection Of Spike Protein, Homa Ghaiedi, Shubham Pandey, Sophia Ezendu, Tibor Szilvasi, Karthik Nayani

Chemical Engineering Faculty Publications and Presentations

A liquid crystal (LC)-based sensing platform for the rapid optical detection of SARS-CoV-2 ' s spike protein's receptor binding domain (RBD) domain is introduced. This platform utilizes a thermotropic LC, hosted on metal-cation decorated substrates, onto which the spike protein can competitively bind. Density functional theory (DFT) calculations guide the experiments that reveal a homeotropic-to-planar transition in the LCs upon exposure to SARS-CoV-2 spike-decorated yeast, providing a basis for sensitive virus detection. The sensor's reversibility/specificity is confirmed through antibody-induced orientation recovery of the LCs initial orientation. Strikingly, the sensor can detect approximate to 2000 copies of the spike protein per …

Development Of A Portable Electroencephalogram With Display, Seth D. Davis

Electronic Theses and Dissertations

In this experiment, the goal was to design, build, and test an Electroencephalogram (EEG) circuit that would then be paired with a touchscreen display as a portable unit for use in Schizophrenic research at East Tennessee State University at the Quillen College of Medicine. The requirements for this prototype denoted that the device had to be able to obtain a signal from two electrodes placed on the head of an individual with a third attached to the ankle as a ground, amplify and filter the signal, and display the results on a touchscreen display for recording and analyzing. The circuit …