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- Creators: Harrington Bioengineering Program
- Member of: Barrett, The Honors College Thesis/Creative Project Collection
Description
Traumatic brain injury (TBI) may result in numerous pathologies that cannot currently be mitigated by clinical interventions. Stem cell therapies are widely researched to address TBI-related pathologies with limited success in pre-clinical models due to limitations in transplant survival rates. To address this issue, the use of tissue engineered scaffolds as a delivery mechanism has been explored to improve survival and engraftment rates. Previous work with hyaluronic acid \u2014 laminin (HA-Lm) gels found high viability and engraftment rates of mouse fetal derived neural progenitor/stem cells (NPSCs) cultured on the gel. Furthermore, NPSCs exposed to the HA-Lm gels exhibit increased expression of CXCR4, a critical surface receptor that promotes cell migration. We hypothesized that culturing hNPCs on the HA-Lm gel would increase CXCR4 expression, and thus enhance their ability to migrate into sites of tissue damage. In order to test this hypothesis, we designed gel scaffolds with mechanical properties that were optimized to match that of the natural extracellular matrix. A live/dead assay showed that hNPCs preferred the gel with this optimized formulation, compared to a stiffer gel that was used in the CXCR4 expression experiment. We found that there may be increased CXCR4 expression of hNPCs plated on the HA-Lm gel after 24 hours, indicating that HA-Lm gels may provide a valuable scaffold to support viability and migration of hNPCs to the injury site. Future studies aimed at verifying increased CXCR4 expression of hNPCs cultured on HA-Lm gels are necessary to determine if HA-Lm gels can provide a beneficial scaffold for stem cell engraftment therapy for treating TBI.
ContributorsHemphill, Kathryn Elizabeth (Author) / Stabenfeldt, Sarah (Thesis director) / Brafman, David (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
NIPAAm co-DEAEMA hydrogels are a potential solution for sustained, local delivery of ketorolac tromethamine. Current methods of postoperative pain management, such as local anesthetics, NSAIDs, and opioids, can be improved by minimizing side effects while still effectively treating severe and extreme pain. Though high doses of ketorolac can be toxic, sustained, local delivery via hydrogels offers a promising solution. Four ketorolac release studies were conducted using PNDJ hydrogels formulated by Sonoran Biosciences. The first two studies tested a range of JAAm concentration between 1.4 and 2.2 mole percent. Both had high initial release rates lasting less than 7 days and appeared to be unaffected by JAAm content. Tobramycin slowed down the release of ketorolac but was unable to sustain release for more than 6 days. Incorporating DEAEMA prolonged the release of ketorolac for up to 14 days with significant reductions in initial burst release rate. Low LCST of NIPAAM co-DEAEMA polymer is problematic for even drug distribution and future in vivo applications.
ContributorsHui, Nathan (Author) / Vernon, Brent (Thesis director) / Heffernan, John (Committee member) / School of International Letters and Cultures (Contributor) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Current culturing methods allow for human neural progenitor cells to be differentiated into neurons for use in diagnostic tools and disease modeling. An issue arises in the relatively low number of cells that can be successfully expanded and differentiated using these current methods, making the progress of research dependent on these cultures as a large number of cells are needed to conduct relevant assays. This project focuses on the expansion and differentiation of human neural progenitor cells cultured on microcarriers and within a rotating bioreactor system as a way to increase the total number of cells generated. Additionally, cryopreservation and the characteristics of these neurons post thaw is being investigated to create a way for long term storage, as well as, a method for standardizing cell lines between multiple experiments at different time points. The experiments covered in this study are aimed to compare the characteristics of differentiated human neurons, both demented and non-demented cell lines between pre-cryopreservation, freshly differentiated neurons and post-cryopreservation neurons. The assays conducted include immunofluorescence, calcium imaging, quantitative polymerase chain reaction, flow cytometry and ELISA data looking at Alzheimer’s disease traits. With the data collected within this study, the use of bioreactors, in addition to, cryopreservation of human neurons for long term storage can be better implemented into human neural progenitor cell research. Both of these aspects will increase the output of these cultures and potentially remove the bottleneck currently found within human neural disease modeling.
ContributorsHenson, Tanner Jay (Author) / Brafman, David (Thesis director) / Kodibagkar, Vikram (Committee member) / School of Life Sciences (Contributor) / Harrington Bioengineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This thesis creative project shares a food and travel blog through a published website that follows my friends and I while we travel through North America reviewing foods that are found in certain areas. This internet blog outlines local cuisines and what makes them unique to certain locations.
Through my personal travels and peer interviews, I have found that this project gave me the opportunity to expand my knowledge on different cultures and regions of the North America and explore how local foods contribute to the cultures in that setting. Additionally, this thesis helped me self-teach myself how to develop a fully published website and practice my web design skills.
Through my personal travels and peer interviews, I have found that this project gave me the opportunity to expand my knowledge on different cultures and regions of the North America and explore how local foods contribute to the cultures in that setting. Additionally, this thesis helped me self-teach myself how to develop a fully published website and practice my web design skills.
ContributorsShabtai, Bat-El Eden (Author) / Vernon, Brent (Thesis director) / Sobrado, Michael (Committee member) / Harrington Bioengineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Spasticity is a neurological disorder in which a target group of muscles remain in a contracted state. In addition to interfering with the function of these muscles, spasticity causes chronic pain and discomfort. Often found in patients with cerebral palsy, multiple sclerosis, or stroke history, spasticity affects an estimated twelve million people worldwide. Not only does spasticity cause discomfort and loss of function, but the condition can lead to contractures, or permanent shortenings of the muscle and connective tissue, if left untreated. Current treatments for spasticity are primarily different forms of muscle relaxant pharmaceuticals. Almost all of these drugs, however, carry unwanted side effects, including total muscle weakness, liver toxicity, and possible dependence. Additionally, kinesiotherapy, conducted by physical therapists at rehabilitation clinics, is often prescribed to people suffering from spasticity. Since kinesiotherapy requires frequent practice to be effective, proper treatment requires constant professional care and clinic appointments, discouraging patient compliance. Consequently, a medical device that could automate relief for spasticity outside of a clinic is desired in the market. While a number of different dynamic splints for hand spasticity are currently on the market, research has shown that these devices, which simply brace the hand in an extended position, do not work through any mechanism to decrease spastic tension over time. Two methods of temporarily reducing spasticity that have been observed in clinical studies are cryotherapy, or the decrease of temperature on a target area, and electrotherapy, which is the delivery of regulated electrical pulses to a target area. It is possible that either of these mechanisms could be incorporated into a medical device aimed toward spastic relief. In fact, electrotherapy is used in a current market device called the SaeboStim, which is advertised to help stroke recovery and spastic reduction. The purpose of this paper is to evaluate the viability of a potential spastic relief device that utilizes cryotherapy to a current and closest competitor, the SaeboStim. The effectiveness of each device in relieving spasticity is reviewed. The two devices are also compared on their ability to address primary customer needs, such as convenience, ease of use, durability, and price. Overall, it is concluded that the cryotherapy device more effectively relieves hand spasticity in users, although the SaeboStim's smaller size and better convenience gives it market appeal, and reveals some of the shortcomings in the preliminary design of the cryotherapy device.
ContributorsWiedeman, Christopher Blaise (Author) / Kleim, Jeffrey (Thesis director) / Buneo, Christopher (Committee member) / W.P. Carey School of Business (Contributor) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Cocaine is a powerful psychomotor stimulant that can affect serotonin (5HT), dopamine, and norepinephrine systems in the brain. Previous studies with 5HT1B receptor agonist, CP94253, have shown dose-dependent decreases in cocaine-self administration in male rats during maintenance. However, these studies do not take into consideration sex differences between male rats and female rats. Female rats introduce a new complexity because they constantly undergo an estrous cycle that consists of four phases, metestrus, diestrus, proestrus, and estrus. It was hypothesized that cocaine infusions and active lever response rates would greatly decrease during proestrus and estrus in comparison to metestrus and diestrus due to hormonal level differences of LH, FSH, progesterone, and estradiol. In this study, female rats were trained to self-administer a training dose of 0.75 mg/kg/infusion on a fixed progressive ratio (FR5). Rats were then pretreated with CP94253 to test the effects of this 5HT1B agonist on female rat cocaine self-administration during the estrous cycle. Results showed there was no three-way interaction between cycle phase, pretreatment, and cocaine dose on infusions or active lever responses. However, pretreatment with CP94253 decreased cocaine intake and active lever responses at high cocaine doses, regardless of cycle phase. Lastly, there was a two-way interaction between pretreatment and cycle phase in which active lever responses decreased during diestrus and proestrus. These results imply that CP94253 enhances cocaine's effect regardless of cycle phase. Future work can work with ovariectomized (OVX) female rats to observe cocaine self-administration during controlled cycle phases.
ContributorsNguyen, Toan Thai Tran (Author) / Neisewander, Janet (Thesis director) / Gipson-Reichardt, Cassandra (Committee member) / Scott, Samantha (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Vagal Nerve Stimulation (VNS) has been shown to be a promising therapeutic technique in treating many neurological diseases, including epilepsy, stroke, traumatic brain injury, and migraine headache. The mechanisms by which VNS acts, however, are not fully understood but may involve changes in cerebral blood flow. The vagus nerve plays a significant role in the regulation of heart rate and cerebral blood flow that are altered during VNS. Here, we examined the effects of acute vagal nerve stimulation on both heart rate and cerebral blood flow. Laser Speckle Contrast Analysis (LASCA) was used to analyze the cerebral blood flow of male Long\u2014Evans rats. Results showed two distinct patterns of responses whereby animals either experienced a mild or severe decrease in heart rate during VNS. Further, animals that displayed mild heart rate decreases showed an increase in cerebral blood flow that persisted beyond VNS. Animals that displayed severe decreases showed a transient decrease in cerebral blood flow followed by an increase that was greater than that observed in mild animals but progressively decreased after VNS. The results suggest two distinct patterns of changes in both heart rate and cerebral blood flow that may be related to the intensity of VNS.
ContributorsHillebrand, Peter Timothy (Author) / Kleim, Jeffrey (Thesis director) / Helms Tillery, Stephen (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
As an incoming STEM student, it can be intimidating thinking about the long academic road ahead. That is why I have written a short book about my greatest success strategies and takeaways from my past four years as a STEM student. I dive into topics including communication, teamwork, time management, growth mindsets, and self-care.
ContributorsConway, Kayla (Author) / Reeves, Scott (Thesis director) / del Mar Navarro, María (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2024-05
Description
Current demographic and water use trends prompt concerns for increasing water scarcity. Water reuse and wastewater reuse can help accommodate for some of these concerns. One application of this wastewater reuse can come in the form of agricultural applications. This, however, raises concerns of human and environmental exposure to antibiotic resistance genes and bacteria (ARGs/ARBs). Organizations such as the Center for Disease Control and Prevention (CDC) and the World Health Organization (WHO) cite increasing exposure and cases of antibiotic resistant bacteria related infections. This has led to a need for a more thorough understanding of risk and risk management strategies for these purposes. Biosolids can be used as fertilizers after treatment from wastewater treatment plants and as a result may be a potential avenue for exposure. Biosolids are activated sludge commonly dewatered and/or further treated for agricultural applications and are a focus of this thesis. The objectives of this thesis are (1) to contribute to a literature review of ARGs in biosolids with a specific focus on the effects of different treatment practices; and (2) quantify E. coli bacteria, intI1 (an integron-integrase gene used as an indicator of anthropogenic pollution), some heavy metals, and nutrients (N, P, and K) for newly collected biosolids samples in a multifactorial-designed lettuce growth experiment. Results found that most data points did not report wastewater treatment type. Additionally, TH/TH-MAD appeared to have lower ARG concentrations relative to other treatment types. Organizations such as the U.S. Environmental Protection Agency (USEPA) and the WHO provide maximum permissible limits of certain contaminants in plants and soils. Results found Cadmium concentrations in lettuce to be above these outlined limits. E. coli bacteria and intI1 results varied. Ultimately, in the future there needs to be more consistent reporting guidelines for obtaining ARG/ARB data and developing risk models for assessing potential exposure.
ContributorsKuppravalli, Aditya (Author) / Hamilton, Kerry (Thesis director) / Conroy-Ben, Otakuye (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2024-05
Description
This thesis investigates the impact of extended use of exoskeletal boots on fatigue levels during physical activity. The study examines the effects of exoskeletal boots on physiological responses, including heart rate, R-R intervals, VO2 levels, and walking durations, compared to conditions without the boots. Participants underwent walking tasks while wearing the boots and performed physiological assessments. Results indicate that exoskeletal boots may mitigate fatigue and enhance endurance, as evidenced by longer walking durations and potentially reduced metabolic demand compared to conditions without the boots. Furthermore, analysis of heart rate and R-R interval data suggests modulation of autonomic nervous system activity with the use of exoskeletal boots. These findings offer insights into the potential benefits of exoskeletal boots in reducing fatigue and improving performance during prolonged physical activity, with implications for various domains including sports, rehabilitation, and military applications. Further research is warranted to elucidate the underlying mechanisms and optimize the utilization of exoskeletal boots for enhancing human performance and well-being.
ContributorsByrne, Emily (Author) / Lockhart, Thurmon (Thesis director) / Arquiza, J.M.R. Apollo (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2024-05