Biomedical Engineering and Bioengineering Commons^™

Electrospun Nanofiber Scaffolds As A Platform For Breast Cancer Research, Carolynn Que

Dissertations, Master's Theses and Master's Reports

Tumorigenesis is a complex process involving numerous cellular signaling cascades and environmental factors. Here, we report the fabrication of 3D scaffolds with different morphologies obtained by to study cancer cell proliferation and migration. Using an FDA approved, biocompatible and biodegradable polymer Polycaprolactone (PCL), we electrospun nanofiber scaffolds having mesh, aligned, and honeycomb morphologies. The role of the morphology and cellular preferences to nutrition in cell adhesion and proliferation was assessed using scaffolds obtained by electrospinning PCL with fluorescent fructose-like molecular probes. Cell viability, cell morphology, localized cellular growth as related to scaffold morphology and availability of the fructose-like molecular probes …

Study Of Silica Nanoparticle Composite On Silica-Hydrogen Peroxide Complexations And Their Effects In Catechol Based Adhesives, Rattapol Pinnaratip

Dissertations, Master's Theses and Master's Reports

Mussel adhesive proteins contain catechol moiety, which allows the protein to crosslinked, solidify, and adhere to surrounding surfaces even under wet conditions. Incorporating the catechol moiety into polymeric adhesive resulted in bioadhesive, which still functions under wet conditions. However, the adhesive must be oxidized in order to crosslink and adhere to surfaces. The oxidation process of catechol adhesive was proven to produce singlet oxygen, superoxide, and hydrogen peroxide (H₂O₂). These reactive oxygen species, with lack of control, can wreak havoc to the biological system causing poor healing and undesired biological response.

Here, we studied the silica …

Lipemia Levels Analysis From Human Blood Samples, Zainab Ibrahim Alshoug

Dissertations, Master's Theses and Master's Reports

Worldwide, an estimated 31% of people who die each year have a cardiovascular disease (CVD), an all-encompassing group of diseases and conditions of the heart or blood vasculature. Access to portable, user-friendly tools to test lipid levels accurately and efficiently, without requiring large volume blood draws, will help improve access to wellness management by reducing costs and facilitating early screening and monitoring of CVD thus improving outcomes. Point of care micro or millifluidic chips to test biofluids that are integrated into detection units are an attractive measurement tool because of their potential for ease of use by patients at home …

Artificial Synthetic Scaffolds For Tissue Engineering Application Emphasizing The Role Of Biophysical Cues, Samerender Nagam Hanumantharao

Dissertations, Master's Theses and Master's Reports

The mechanotransduction of cells is the intrinsic ability of cells to convert the mechanical signals provided by the surrounding matrix and other cells into biochemical signals that affect several distinct processes such as tumorigenesis, wound healing, and organ formation. The use of biomaterials as an artificial scaffold for cell attachment, differentiation and proliferation provides a tool to modulate and understand the mechanotransduction pathways, develop better in vitro models and clinical remedies. The effect of topographical cues and stiffness was investigated in fibroblasts using polycaprolactone (PCL)- Polyaniline (PANI) based scaffolds that were fabricated using a self-assembly method and electrospinning. Through this …

Developing Machine Learning Algorithms For Behavior Recognition From Deep Brain Signals, Hosein Golshan Mojdehi

Electronic Theses and Dissertations

Parkinson’s disease (PD) is a neurodegenerative condition and movement disorder that appears with symptoms such as tremor, rigidity of muscles and slowness of movements. Deep brain stimulation (DBS) is an FDA-approved surgical therapy for essential tremor and PD. Despite the fact that DBS substantially alleviates the motor signs of PD, it can cause cognitive side effects and speech malfunction mainly due to the lack of adaptivity and optimality of the stimulation signal to the patients’ current state. A behavior-adapted closed-loop DBS system may reduce the side effects and power consumption by adjusting the stimulation parameters to patients’ need.

Behavior recognition …

The Effects And Analysis Of Implant Type And Surgical Approach In Total Hip Arthroplasty Dislocation Resistance, Brittany Marshall

Electronic Theses and Dissertations

Total hip arthroplasty (THA) is one of the most successful orthopaedic surgeries performed, in which the hip joint is reconstructed to decrease pain and to improve the functionality to the joint. Although these surgeries are very successful, there still remain areas for improvement, such as failures due to instability and dislocation of the implanted joint. The purpose of this thesis is to investigate the effect of surgical entrance approach on dislocation, the effect of implant type, and the effect of capsule repair and closure. The need to quantify the resistance to dislocation is important in understanding the effect that each …

Transcatheter Mitral Valve Replacement: Structural And Hemodynamic Analysis, Saba Ravaghi

Electronic Theses and Dissertations

Transcatheter mitral valve replacement (TMVR) is being developed to become a substitute therapy for surgery in prohibitive or high surgical risk patients to treat severe mitral regurgitation. A limited number of TMVR systems are under clinical evaluation. However, transcatheter mitral valve (TMV) long-term durability and hemodynamic performance is not known. TMV durability and hemodynamics must match with that of surgical bioprostheses for potential commercialization of TMVR. Experimental and computational approaches were used to find the leaflets’ three-dimensional anisotropic mechanical properties in a transcatheter Edwards SAPIEN 3 valve and a surgical Carpentier-Edwards PERIMOUNT Magna mitral valve and finite element (FE) simulations …

Perivascular Waste Metabolites Clearance In Central Nervous System (Cns), Yiming Cheng

Dissertations

Efficient clearance of interstitial waste metabolites is essential for normal brain homeostasis. Such effective clearance is hampered by the lack of a lymphatic system in the brain, and the cerebrospinal fluid (CSF) is unable to clear large size waste metabolites in the brain. Here, a novel idea that brain arterial endothelium and smooth muscle cells reactivity regulates the clearance of these water-insoluble large size waste metabolites through the perivascular dynamic exchange, and that low dose ethanol promotes this perivascular clearance is proposed.

In Aim 1, the biodistribution of a large size waste metabolite (Amyloid-β protein mimic) in rat perivascular space …

Cerebro-Vascular Disruption Mediated Initiation And Propagation Of Traumatic Brain Injury In A Fluid Percussion Injury Model, Xiaotang Ma

Dissertations

Traumatic brain injury (TBI) is a major health problem for over 3.17 million people in the US. There is no FDA-approved drug for the treatment because the injury mechanisms have not been clearly identified. The knowledge gap is addressed here by the lateral fluid percussion injury (FPI) rat model, through the understanding of layer-structured mechanisms from physical vascular rupture to acute necrosis, as well as biochemical changes in perivascular space as secondary events.

Firstly, the cerebrovascular hemorrhage and related infarct volume are investigated as the primary events in moderate FPI, which is found to be increased with injury severity in …

Micro Pipes – A Portable Integrated Platform For Electrochemical Sensing Using Essence Architecture, Hansin Kim

Theses

The field of microfluidics and lab-on-chip (LOC) technology has the potential to have a truly transformative effect in biological engineering. This includes areas such as single-cell analysis, environmental monitoring, regenerative medicine, and point-of-care diagnostics. Yet despite being the subject of intense research over the past two decades, LOC devices have not been widely adopted. It is increasingly evident that there is a need for an effective and adaptable integration strategy to realize the potential of this technology.

Presented in this thesis is a design for a chip-to-world interface that aims to improve integration while maintaining cost-efficiency and ease of fabrication. …

Lithium As A Possible Therapeutic Drug In Posttraumatic Brain Injury, Tulika Das

Theses

Lithium, a popular drug for treating mental health disorder has shown promising effect in recent research on traumatic brain injury (TBI). The mechanism of lithium for treating bipolar mood disorder is still not properly understood, but recent studies showed that lithium is neuroprotective in TBI. In my thesis, the neuroprotective effects of lithium were examined in primary neuronal culture and mild blunt injury using rodent model of Lateral Fluid Percussion Injury (LFPI). At first determination of the neuroprotective/toxicity effects of lithium in neuronal culture was done and observed that 0.5 - 1.0 mM concentrations were found to be neuroprotective as …

A Microfluidic Paper-Based Analytical Device For Early Diagnosis And Prognosis Of Acute Myocardial Infarction, Lim Wei Yin

Student Works (2020-2029)

Acute myocardial infarction (AMI), also termed as heart attack, is often clinically screened by blood test through the measurement of cardiac biomarkers (i.e., troponin (T or I), creatine kinase (CK−MB) and myoglobin) and electrocardiography (ECG) changes which are presented to the hospital. However, the early diagnosis of AMI is challenging because the detection of biomarkers such as troponin (T or I) and CK−MB are only reliable at the intermediate and later stages (> 6 hours after chest pain onset), during myocardial injury and myocardial infarction. On the other hand, myoglobin often been used as early biomarker which is detectable within …

Design And Development Of A Perfusion Bioreactor With Internal Volume Expansion And Cell Retention For Cell And Gene Therapy Manufacturing, Corinna Doris

KGI Theses and Dissertations

Economically producing patient-specific cell therapies at commercial levels remains a challenge as it requires manufacturing separate batches per patient where the production system must be scaled-out rather than scaled-up to supply more patient doses. The resulting high production cost and consequent price-point can limit patient access. Specifically, the current cell expansion processes are highly manual and laborious, with the number and complexity of operations and components increasing the opportunities for failure and contamination. This work therefore aims to design a mechanically simple bioreactor that is better suited for scale-out by consolidating the cell expansion process to fewer components, vessels, and …

Development Of A Low-Cost, Open Source Miniature Rotary Cell Culture System To Simulate Microgravity Within An Irradiated Environment, Elizabeth Vargis, Jr Dennison

Browse all Datasets

A major challenge for astronauts in long-duration space travel is combatting the hazardous spaceflight environment caused by microgravity and increased levels of ionizing radiation. Microgravity damages cellular DNA by increasing the production of harmful reactive oxygen species, while ionizing radiation damages DNA by creating double-stranded DNA (dsDNA) breaks. Cellular damage due to microgravity and radiation has been investigated using ground-based models, but most models consider microgravity and ionizing radiation alone, or asynchronously. Synchronous modeling better mimics spaceflight conditions and can be used to understand the combined effects of microgravity and ionizing radiation. However, commercially available devices to model microgravity and …

Liver Cancer: Current And Future Trends Using Biomaterials, Sue Anne Chew, Stefania Moscato, Sachin George, Bahareh Azimi, Serena Danti

Health & Biomedical Sciences Faculty Publications

Hepatocellular carcinoma (HCC) is the fifth most common type of cancer diagnosed and the second leading cause of death worldwide. Despite advancement in current treatments for HCC, the prognosis for this cancer is still unfavorable. This comprehensive review article focuses on all the current technology that applies biomaterials to treat and study liver cancer, thus showing the versatility of biomaterials to be used as smart tools in this complex pathologic scenario. Specifically, after introducing the liver anatomy and pathology by focusing on the available treatments for HCC, this review summarizes the current biomaterial-based approaches for systemic delivery and implantable tools …

Finding A Viable Neural Network Architecture For Use With Upper Limb Prosthetics, Maxwell Lavin

Master of Science in Computer Science Theses

This paper attempts to answer the question of if it’s possible to produce a simple, quick, and accurate neural network for the use in upper-limb prosthetics. Through the implementation of convolutional and artificial neural networks and feature extraction on electromyographic data different possible architectures are examined with regards to processing time, complexity, and accuracy. It is found that the most accurate architecture is a multi-entry categorical cross entropy convolutional neural network with 100% accuracy. The issue is that it is also the slowest method requiring 9 minutes to run. The next best method found was a single-entry binary cross entropy …

Development Of High-Speed Photoacoustic Imaging Technology And Its Applications In Biomedical Research, Yun He

McKelvey School of Engineering Graduate Student Theses & Dissertations

Photoacoustic (PA) tomography (PAT) is a novel imaging modality that combines the fine lateral resolution from optical imaging and the deep penetration from ultrasonic imaging, and provides rich optical-absorption–based images. PAT has been widely used in extracting structural and functional information from both ex vivo tissue samples to in vivo animals and humans with different length scales by imaging various endogenous and exogenous contrasts at the ultraviolet to infrared spectrum. For example, hemoglobin in red blood cells is of particular interest in PAT since it is one of the dominant absorbers in tissue at the visible wavelength.The main focus of …

Rhodococcus Opacus Pd630 Genetic Tool Development To Enable The Conversion Of Biomass, Drew Michael Delorenzo

McKelvey School of Engineering Graduate Student Theses & Dissertations

The discovery of fossil fuels facilitated a new era in human history and allowed many firsts, such as the mass production of goods, the ability to travel and communicate long distances, the formation of population dense cities, and unprecedented improvements in quality of life. Alternative sources of energy and chemicals are needed, however, as hydrocarbon reserves continue to deplete and the effects of burning fossils on the planet become better understood. Lignocellulosic biomass is the most abundant raw material in the world and a viable alternative to petroleum-derived products. The pre-treatment of lignocellulose (e.g., thermocatalytic depolymerization, enzymatic hydrolysis, pyrolysis, etc.) …

Three-Dimensional Image Reconstruction In Transcranial Photoacoustic Computed Tomography, Joemini Poudel

McKelvey School of Engineering Graduate Student Theses & Dissertations

Photoacoustic computed tomography (PACT) is an emerging imaging modality that exploitsoptical contrast and ultrasonic detection principles to form images of the photoacousticallyinduced initial pressure distribution within tissue. The PACT reconstruction problemcorresponds to an inverse source problem in which the initial pressure distribution is recoveredfrom measurements of the radiated pressure wavefield. A major challenge in transcranialPACT brain imaging is compensation for aberrations in the measured data due to the presenceof the skull. Ultrasonic waves undergo absorption, scattering and longitudinal-to-shear wavemode conversion as they propagate through the skull. To properly account for these effects, awave-equation-based inversion method should be employed that can …

Ph-Sensitive Oxygen Release Microspheres To Enhance Cell Survival In Ischemic Condition, Zhongting Liu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Ischemic diseases such as myocardial infarction, stroke and limb ischemia are severe cardiovascular diseases with high rate of death and millions of people suffered from these diseases. Under ischemic environment, cells die due to deficient supply of nutrient and oxygen. To regenerate ischemic tissues, stem cell therapy is a promising approach because stem cells can differentiate into cells necessary for the regeneration. However, stem cell therapy has limitations. For example, few cells can survive under harsh ischemic environment. To enhance stem cells survival, implantation of oxygen release microspheres to sustained supply cells with oxygen represents an effective strategy. Previously, our …