Matching Items (17)
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- All Subjects: Traumatic Brain Injury
- Creators: Harrington Bioengineering Program
- Resource Type: Text
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
DescriptionMy main goal for my thesis is in conjunction with the research I started in the summer of 2010 regarding the creation of a TBI continuous-time sensor. Such goals include: characterizing the proteins in sensing targets while immobilized, while free in solution, and while in free solution in the blood.
ContributorsHaselwood, Brittney (Author) / LaBelle, Jeffrey (Thesis director) / Pizziconi, Vincent (Committee member) / Cook, Curtiss (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2011-12
Description
The goal of this project was to explore biomimetics by creating a jellyfish flying device that uses propulsion of air to levitate while utilizing electromyography signals and infrared signals as mechanisms to control the device. Completing this project would require knowledge of biological signals, electrical circuits, computer programming, and physics to accomplish. An EMG sensor was used to obtain processed electrical signals produced from the muscles in the forearm and was then utilized to control the actuation speed of the tentacles. An Arduino microprocessor was used to translate the EMG signals to infrared blinking sequences which would propagate commands through a constructed circuit shield to the infrared receiver on jellyfish. The receiver will then translate the received IR sequence into actions. Then the flying device must produce enough thrust to propel the body upwards. The application of biomimetics would best test my skills as an engineer as well as provide a method of applying what I have learned over the duration of my undergraduate career.
ContributorsTsui, Jessica W (Author) / Muthuswamy, Jitteran (Thesis director) / Blain Christen, Jennifer (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
This project details a magnetic field detection system that can be mounted on an unmanned aerial vehicle (UAV). The system is comprised of analog circuitry to detect and process the magnetic signals, digital circuitry to sample and store the data outputted from the analog front end, and finally a UAV to carry and mobilize the electronic parts. The system should be able to sense magnetic fields from power transmission lines, enabling the determination of whether or not current is running through the power line.
ContributorsTheoharatos, Dimitrios (Co-author) / Brazones, Ryan (Co-author) / Pagaduan, Patrick (Co-author) / Allee, David (Thesis director) / Karady, George (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2015-05
Description
The endogenous response of neural stem cell/progenitor (NPSC) recruitment to the brain injury environment following a traumatic brain injury (TBI) is currently under heavy investigation. Mechanisms controlling NPSC proliferation and migration to the brain injury environment remain unclear; however, it is thought that the vascular extracellular matrix proteins (e.g. laminin, fibronectin, and vitronectin) and vascular endothelial growth factor (VEGF) play a role in mediating NPSC behavior through vasophillic interactions. This project attempts to uncover potential VEGF-ECM crosstalk in mediating migration and proliferation. To investigate migration, neurospheres were seeded on ECM-coated wells supplemented with VEGF and without VEGF, and neural outgrowth was measured at days 0, 1, 3, and 8 using differential interference contrast microscopy. Furthermore, single-cell NPSCs were seeded on ECM-coated Transwell membranes with VEGF supplemented media on one side and without VEGF to look at chemotactic migration. Migrated NPSCs were visualized with DAPI nuclear stain and imaged with an inverted fluorescent microscope. To investigate NPSC proliferation, NPSCs were seeded on ECM coated plates as in the radial migration assay and visualized with EdU on day 8. Total proliferation was measured by seeding NPSCs on ECM coated 96-well plates and incubating them with MTT on days 3 and 6. Proliferation was measured using a spectrophotometer at 630nm and 570nm wavelengths. It was found that VEGF-laminin crosstalk synergistically increased radial migration, but may not play a role in chemotactic migration. Understanding the mechanisms behind VEGF-laminin crosstalk in NPSC proliferation and migration may provide crucial information for the design of stem cell transplantation therapies in the future.
ContributorsMillar-Haskell, Catherine Susan (Author) / Stabenfeldt, Sarah (Thesis director) / Addington, Caroline (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2015-05
Description
Diabetes mellitus is a disease characterized by many chronic and acute conditions. With the prevalence and cost quickly increasing, we seek to improve on the current standard of care and create a rapid, label free sensor for glycated albumin (GA) index using electrochemical impedance spectroscopy (EIS). The antibody, anti-HA, was fixed to gold electrodes and a sine wave of sweeping frequencies was induced with a range of HA, GA, and GA with HA concentrations. Each frequency in the impedance sweep was analyzed for highest response and R-squared value. The frequency with both factors optimized is specific for both the antibody-antigen binding interactions with HA and GA and was determined to be 1476 Hz and 1.18 Hz respectively in purified solutions. The correlation slope between the impedance response and concentration for albumin (0 \u2014 5400 mg/dL of albumin) was determined to be 72.28 ohm/ln(mg/dL) with an R-square value of 0.89 with a 2.27 lower limit of detection. The correlation slope between the impedance response and concentration for glycated albumin (0 \u2014 108 mg/dL) was determined to be -876.96 ohm/ln(mg/dL) with an R-squared value of 0.70 with a 0.92 mg/dL lower limit of detection (LLD). The above data confirms that EIS offers a new method of GA detection by providing unique correlation with albumin as well as glycated albumin. The unique frequency response of GA and HA allows for modulation of alternating current signals so that several other markers important in the management of diabetes could be measured with a single sensor. Future work will be necessary to establish multimarker sensing on one electrode.
ContributorsEusebio, Francis Ang (Author) / LaBelle, Jeffrey (Thesis director) / Pizziconi, Vincent (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
The main objective of this research is to develop and characterize a targeted contrast agent that will recognize acute neural injury pathology (i.e. fibrin) after traumatic brain injury (TBI). Single chain fragment variable antibodies (scFv) that bind specifically to fibrin have been produced and purified. DSPE-PEG micelles have been produced and the scFv has been conjugated to the surface of the micelles; this nanoparticle system will be used to overcome limitations in diagnosing TBI. The binding and imaging properties will be analyzed in the future to determine functionality of the nanoparticle system in vivo.
ContributorsRumbo, Kailey Michelle (Author) / Stabenfeldt, Sarah (Thesis director) / Kodibagkar, Vikram (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Growing concern over health risks associated with environmental contaminants has prompted an increase in the search for effective detection methods. The available options provide acceptable sensitivity and specificity, but with high purchase and maintenance costs. Herein, a low-cost, portable environmental contaminant sensor was developed using electrochemical techniques and an efficient hydrogel capture mechanism. The sensor operates with high sensitivity and maintains specificity without the added requirement of extensive electrode modification. Rather, specificity is obtained by choosing specific potential regions in which individual contaminants show reduction or oxidation activity. A calibration curve was generated showing the utility of the sensor in detecting gas compounds reliably in reference to a current state of the art sensor. Reusability of the sensor was also demonstrated with a cyclic exposure test in which response reversibility was observed. As such, the investigated sensor shows great promise as a replacement technology in the current environmental contaminant detector industry.
ContributorsMarch, Michael Stephen (Author) / LaBelle, Jeffrey (Thesis director) / Caplan, Michael (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
This paper summarizes the [1] ideas behind, [2] needs, [3] development, and [4] testing of 3D-printed sensor-stents known as Stentzors. This sensor was successfully developed entirely from scratch, tested, and was found to have an output of 3.2*10-6 volts per RMS pressure in pascals. This paper also recommends further work to render the Stentzor deployable in live subjects, including [1] further design optimization, [2] electrical isolation, [3] wireless data transmission, and [4] testing for aneurysm prevention.
ContributorsMeidinger, Aaron Michael (Author) / LaBelle, Jeffrey (Thesis director) / Frakes, David (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05
Description
Traumatic brain injury (TBI) can result in many pathologies, one of which being coagulopathy. TBI can progress to hemorrhagic lesions and increased intercranial pressure leading to coagulopathy. The coagulopathy has been linked to poor clinical outcomes and occurs in 60% of severe TBI cases. To improve hemostasis, synthetic platelets (SPs) have been repurposed. SPs are composed of a poly(N-isopropylacrylamide-co-acrylic-acid) microgel, conjugated with a fibrin-specific antibody and are biomimetic in their ability to deform and collapse within a fibrin matrix. The objective of this study is to diminish coagulopathy with a single, intravenous injection of SPs, and subsequently decrease neuropathologies. TBI was modeled in animal cohorts using the well-established controlled cortical impact and SPs were injected 2-3 hours post-injury. Control cohorts received no injection. Brain tissue was harvested at acute (24h) and delayed (7 days) time points post-TBI, and fluorescently imaged to quantify reactive astrocytes (GFAP+), microglial morphology and presence (Iba1+), and tissue lesion spared. SP-treatment resulted in significant reduction of GFAP expression at 7 days post-TBI. Furthermore, SP-treatment significantly reduced the percent difference from 24h to 7 days in microglia/macrophage per field compared to the control. For microglial morphology, SP-treated cohorts observed a significant percent difference in endpoints per soma from 24h to 7 days compared to untreated cohorts. However, microglial branch length significantly decreased in percent difference from 24h to 7 days when compared to the control. Finally, tissue sparing did not significantly decrease between 24h and 7 day for SP-treated cohorts as was observed in untreated cohorts, implying inhibition of delayed necrosis. Overall, these results suggest decreased neuroinflammation by 7 days, supporting SPs as potentially therapeutic post-TBI.
ContributorsTodd, Jordan Cecile (Author) / Stabenfeldt, Sarah (Thesis director) / Bharadwaj, Vimala (Committee member) / Harrington Bioengineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05