Biological Engineering electronic theses and dissertations - Engineering (MU)
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The items in this collection are the theses and dissertations written by students of the Department of Biological Engineering. Some items may be viewed only by members of the University of Missouri System and/or University of Missouri-Columbia. Click on one of the browse buttons above for a complete listing of the works.
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Item Engineering delivery systems for the treatment of Non-Hodgkin lymphoma(University of Missouri--Columbia, 2025) Shelton, Joshua; Ulery, Bret[EMBARGOED UNTIL 08/01/2026] Hematological cancers, including various leukemias and lymphomas, are among the top 10 cancers diagnosed in people. The leukemia and lymphoma society estimates that there are nearly 1.7 million people in the United States living with or in remission from hematological cancers. The frontline therapeutics for these diseases usually consist of conventional chemotherapeutics, such as RCHOP (i.e., Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisolone), a commonly used therapeutic regimen for many Non-Hodgkin lymphomas. While therapeutic remission can occur in 50% - 80% of these patients, nearly half are expected to develop relapsing or refractory disease. There exists a clear clinical need to generate targeted therapeutics that avoid undesirable side effects as well as can sufficiently address primary cancer to prevent follow-on disease. To address this issue, peptides have emerged in recent years as a novel improvement in cancer treatment, however, these drugs are limited by their poor cell penetration and serum instability. Lipidation of peptides, producing peptide amphiphiles, has been shown to allow for hydrophobically-driven self-assembly into peptide amphiphile micelles. There are many advantages to employing peptide amphiphile micelles as drug delivery devices, including improved serum stability, higher local therapeutic concentration, and co-loading of other materials, such as chemotherapeutic drugs or multiple PAs. In this dissertation, materials will be presented that utilize the peptide amphiphile micelle platform for the treatment of cancer along with the optimization of targeting elements that may be used to improve their drug delivery capacity. First to be discussed is the delivery of a novel, cytotoxic peptide (i.e., POSH(3.3A)-Tat) by micelle for the treatment of Non- Hodgkin lymphoma and multiple myeloma. This will be followed by foundational work focused on the targeting of Non-Hodgkin lymphoma using aptamers. Finally, a complement to aptamers in the antibody-mediated targeting of peptide amphiphile micelles will be covered.Item Development of novel biomarkers for assessing pulmonary and cardiopulmonary function utilizing hyperpolarized gas MRI(University of Missouri--Columbia, 2025) García Delgado, Gabriela María; Thomen, Robert P.[EMBARGOED UNTIL 08/01/2026] Magnetic Resonance Imaging (MRI) is an advanced imaging technique that transformed the field of Radiology. Its' capability of providing such high-resolution imaging without exposing patients to ionizing radiation changed the field of medical diagnosis and treatment. The presence of this imaging modality has allowed scientists to expand on quantitative methods to further improve the precision and application of MRI in disease management. Although an excellent imaging modality, it is unable to provide informative pulmonary images regarding lung structure and lung function due to low proton density in the lungs. HPG MRI is an innovative imaging modality that is now clinically used and allows for the visualization of ventilation capabilities and gas exchange efficiency in patients. Compared to the common clinical standard for assessing lung structure and lung function, pulmonary function tests (PFTs), HPG MRI provides regional specificity that PFTs lack. This dissertation presents various novel quantification methods utilizing HPG MRI so that personalized medicine and cost reduction can be achieved when used in clinical and research settings. The first novel technique developed and presented in this dissertation involves the development of a three-dimensional spatial ventilation defect focality/sparseness quantifier utilizing HPG MRI, a Cluster Index (CI). This technique was validated utilizing synthesized spherical data and synthesized lung defects to assimilate real pulmonary ventilation defects. This new method was also utilized to compare CIs among different pulmonary diseases such as ventilation images from asthmatic, CF, and COPD subjects. This method may allow for the investigation of potential information regarding underlying pathophysiology that has yet to be found and potential differences in defect focality across different diseases and disease severities. The second study presented in this dissertation involved the development of a graphical user interface that would allow for the assessment of reader manually selected thresholds and compare these to existing VDP quantifying methods. Image features and potential influence of these in threshold selections were also assessed and compared among readers. The results provide insight into what would be the best VDP quantifying method, if the existing thresholds match visual assessments, and the agreement between reader selected thresholds and visually estimated VDPs. The third technique developed and presented entails the performance of singular value decomposition to construct low-noise approximation of FID data, and time domain curve fitting on all free induction decays to obtain a dynamic RBC/membrane ratio and oscillation amplitude quantification. This new marker has the potential to be used as an imaging biomarker to assess disease severity, treatment response, and allow for reduced costs in HPG MRI due to the denoising properties in SVD. The findings from this dissertation will contribute to the development of new imaging biomarker methods to quantify defect focality, disease state/progression, and a standardized DP quantifying protocol.Item The exploration of pulmonary dynamics in e-cigarette users utilizing hyperpolarized gas MRI(University of Missouri--Columbia, 2025) Parks, Isabella; Thomen, Robert[EMBARGOED UNTIL 05/01/2026] The lungs are remarkably efficient organs, designed to sustain life through continuous exchange of gases essential to metabolism and cellular function. From birth onward, they operate with little conscious effort, yet they remain susceptible to a wide range of environmental and behavioral influences. As respiratory illnesses affect a growing portion of the global population, (Collaborators., 2023) the ability to monitor, evaluate, and preserve pulmonary function is becoming increasingly critical. Advances in diagnostic imaging, particularly those that assess not just anatomical but also functional aspects of the lungs, are central to improving early detection and intervention in chronic and emerging respiratory conditions. The increasing prevalence of vaping among young adults (Becker TD, 2022) has catalyzed a new wave of concern regarding respiratory health, prompting researchers and clinicians to interrogate the long-term consequences of this relatively modern practice. (Muthumalage, 2019) Though e-cigarettes are often marketed as harm-reduction devices, a safer alternative to combustible tobacco, accumulating evidence suggests that their inhaled constituents may not be benign. Early studies have begun to uncover subtle disruptions in lung physiology linked to vaping (Casey AM, 2020) yet the field remains nascent, particularly when it comes to individuals who have never or rarely engaged in traditional smoking. This research seeks to bridge that gap by investigating whether measurable changes in lung function occur among young adults who regularly vape but have little or no prior exposure to traditional cigarettes. Specifically, this study examines whether hyperpolarized xenon magnetic resonance imaging, a modality capable of visualizing both ventilation and gas exchange, can detect early biomarkers of pulmonary impairment in this cohort. It also investigates whether these biomarkers correlate with reported respiratory symptoms, or if the symptomatology reflects a mismatch between physiological data and perceived impairment, potentially implicating non-pulmonary origins. A cross-sectional study design was employed to enroll individuals aged 18--30 who reported at least one year of regular e-cigarette use and negligible, if any, history of combustible tobacco exposure. Each participant underwent hyperpolarized xenon magnetic resonance imaging to quantify ventilation heterogeneity, gas exchange efficiency, and potential airway abnormalities. Complementary surveys and exposure assessments were administered to gather detailed information on vaping behaviors, including device type, usage frequency, duration, and nicotine concentration, as well as relevant environmental exposures. These datasets supported a multifactorial analysis of potential contributors to pulmonary dysfunction. Data from the vaping cohort were subsequently compared to previously acquired datasets from healthy, age-matched controls to evaluate deviations in lung function metrics. This project was structured around two primary aims. The first was to identify imaging biomarkers of lung function associated with clinical symptomatology in e-cigarette users, providing insight into subclinical physiological changes that may precede overt disease. The second was to examine how environmental and behavioral factors contributed to these findings by integrating imaging data with participant-specific behavioral and exposure profiles.Item Utilizing hydrogen peroxide to promote angiogenesis in bone regeneration(University of Missouri--Columbia, 2025) Kee, Alyson; Ulery, Bret[EMBARGOED UNTIL 05/01/2026] Non-union bone fractures occur when the bone does not properly heal after employing internal and external fixation and instead requires additional, more complicated medical interventions to achieve proper tissue repair. These injuries are particularly debilitating for patients, due to long recovery times, invasiveness, and complications associated with current treatment methods leveraging autografts and allografts. Newer therapies rely on scaffold-based systems loaded with expensive growth factors such as Bone Morphogenetic Protein 2 (BMP-2) and Vascular Endothelial Growth Factor (VEGF). As an alternative to these costly bioactive proteins, simple signaling molecules (SSMs) are an exciting tool being studied for their role in cellular signaling, as they are readily accessible, inexpensive, processible, and controllable. In particular, hydrogen peroxide (H2O2) is an attractive SSM which I have evaluated in this research as an alternative to VEGF. To examine its angioinductive effects, mesenchymal stem cells (MSCs) were exposed to varying concentrations of H2O2 and evaluated for certain factors indicative of cell viability and endothelial differentiation. Specifically, viability was studied based on cell count and adenosine triphosphate (ATP) production over a 7-day period. MSC endothelial differentiation was evaluated by measuring the endothelial markers von Willebrand Factor (vWF) and angiopoietin-1 (ang-1) using confocal microscopy and an enzyme linked immunosorbent assay (ELISA), respectively. The combined results of these experiments confirmed that H2O2 is indeed angioinductive promoting endothelial differentiation in vitro. A therapeutic window of 5 - 150 µM was determined with doses below this being sub-therapeutic and ones above this being cytotoxic. These initial promising results will help guide future research in which a sustained release method of H2O2 will be developed for future vascularized bone regenerative engineering applications such as in the repair of non-union fractures.Item Investigation of methods to characterize macromolecular interactions and stability in wine(University of Missouri--Columbia, 2025) Burken, Olivia; Sommer, Stephan[EMBARGOED UNTIL 05/01/2026] Accurate accounts of wine proteins, polysaccharides, polymeric pigments, and their subsequent reactions with other constituents are necessary to understanding color stability, precipitation, and organoleptic properties. Interactions between wine proteins and polysaccharides have the capacity to control the shelf-life, pigment precipitation, and turbidity of red wines. In order to reproduce and stabilize high quality wines, these molecular attributes and interactions should be further recognized. This study evaluates various model polysaccharides -- carboxymethylcellulose (CMC), mannoproteins, and pectin varieties -- and model proteins -- egg-white protein, oat protein, and bovine serum albumin (BSA) -- for their interactions within red wine systems. Characterizations of polymeric pigment precipitation are also evaluated via assay modifications and analysis. This study demonstrates the capabilities of ζ-potential analysis and size particle measurements to foretell and illustrate the interactions between macromolecules in complex systems. Interactions between model wine macromolecules can be evaluated at a degree that cannot be grasped with other analytical techniques. The assay provides effective differentiation of protein-precipitable and polyphenol-based precipitable polymeric pigments and permits valuable characterization of polysaccharide-polyphenol adducts and their effects on wine and color stability. This study demonstrates the capabilities of ζ-potential analysis and size particle measurements to foretell and illustrate the interactions between macromolecules in complex systems. Interactions between model wine macromolecules can be evaluated at a degree that cannot be grasped with other analytical techniques. The assay provides effective differentiation of protein-precipitable and polyphenol-based precipitable polymeric pigments and permits valuable characterization of polysaccharide-polyphenol adducts and their effects on wine and color stability.