Biomedical Engineering and Bioengineering Commons^™

Consequences Of Trpm7 Kinase Inactivation In Immune Cells, Pavani Beesetty

Browse all Theses and Dissertations

The characteristic feature of ubiquitously expressed transient receptor potential melastatin 7 (TRPM7) protein is the presence of a C-terminal atypical kinase domain fused to a cation channel domain. Even though this protein has been implicated in a number of physiological and pathological processes, the mechanisms regulating TRPM7 channel activity are poorly understood. In the present study, regulation of TRPM7 channel by its kinase activity was investigated using the TRPM7 kinase-dead knock-in mouse (KD mouse). These mice have a point mutation Lys1646Arg in the kinase region abrogating the kinase activity. Examining TRPM7 channel activity in KD peritoneal macrophages revealed that TRPM7 …

Study Of Mri Signal In The Presence Of Discrete Spherical Magnetic Particles, Paul Kokeny

Wayne State University Dissertations

Simulating signal behavior in Magnetic Resonance imaging (MRI) is often a necessary step in being able to understand how signal relates to certain physiological parameters. One such parameter of interest in the body is magnetic susceptibility since it is related to iron content. The bulk magnetic susceptibility of an object is a property that describes how magnetized it becomes when placed in an external magnetic field. When the bulk susceptibility of an object arises from the presence of discrete magnetic inclusions, the MRI phase signal inside the object can no longer be determined analytically by assuming it has a continuous …

Optical Coherence Tomography Application To Alopecia In The Scalp, Elizabeth Melcher

Research Opportunities for Engineering Undergraduates (ROEU) Program 2017-18

Alopecia is the loss of hair, whether it be from the scalp or other regions of the body. Current techniques used to best diagnose and track alopecia are often invasive, requiring a biopsy for results. The use of the OCT, or optical coherence tomography, could drastically improve a patient’s experience in undergoing a diagnosis while proving accurate results. The objective of this study is to develop diagnostic algorithms for the rapid, non-invasive diagnosis of alopecia with OCT. The first step is collecting OCT images of a healthy scalp to understand the anatomical structures with the imaging technique.

Characterization Of Electroactive Nanofibers For Nerve Regeneration, Jean-Yves Azar

Research Opportunities for Engineering Undergraduates (ROEU) Program 2017-18

In the event of peripheral nerve injury, loss of function may occur as the result of a severed nerve. Hollow nerve gap conduits are used to provide a protected environment for nerves to reconnect and regain function, although therapies for nerve gaps larger than 3 cm lack a stable environment for nerves to reconnect. Development of a nerve guide conduit filler has been proposed to mimic the cell’s microenvironment. This would lead to increased functional regeneration. We are aiming to create a biomaterial to act as a filler for the hollow nerve gap conduits to promote functional regeneration of the …

Developing Vascular Graft From Adipose-Derived Stem Cells, Ashley C. Apil

Research Opportunities for Engineering Undergraduates (ROEU) Program 2017-18

This project aims to differentiate adipose-derived stem cells into fibroblasts through the addition of platelet-derived growth factor (PDGF) into the culture media. Differentiation protocol will be optimized, then successful differentiation will be verified through PCR analysis. The ASC-fibroblasts will then be seeded into a ring construct as outlined by the protocol by Lam et al. The ring constructs will be tensile tested and analyzed through histology to characterize their strength and cellularity.

A Collaborative Solution To Harmful Algal Blooms In Utah, Kyle Hillman, Bethany Jensen, Ammon Balle

Research on Capitol Hill

Harmful algal blooms (HABs)…

• affect Utah Lake, Scofield Reservoir, Jordanelle Reservoir, Mantua Lake, and other water bodies throughout Utah
• are toxic to public health, the environment, and the economy

Investigation Of The Ms2 Bacteriophage Capsid As An Mri-Capable, Brain-Targeted Nanoparticle Platform, Stephanie M. Curley

Legacy Theses & Dissertations (2009 - 2024)

Novel methods are needed to traverse the blood-brain barrier (BBB) and deliver drugs to specific targets in the brain. To this end, MS2 bacteriophage was explored as a multifunctional transport and targeting vector. The MS2 capsid exterior was modified with two different targeting moieties for delivery across the BBB and targeting specific regions of interest in the brain. Successful modification of MS2 capsids with a brain targeting peptide and NMDAR2D-targeting antibody was confirmed by immunoblotting and fluorescence detection. To measure transport efficiency of MS2 particles across an in vitro BBB model, a highly sensitive RT-qPCR protocol was developed and implemented. …

Inhibition Of Apoptosis Exacerbates Fatigue-Damage Tendon Injuries In An In Vivo Rat Model, R. Bell, M. A. Robles-Harris, M. Anderson, D. Laudier, M. B. Schaffler, E. L. Flatow, N. Andarawis-Puri

Publications and Research

Tendinopathy is a common and progressive musculoskeletal disease. Increased apoptosis is an end-stage tendinopathy manifestation, but its contribution to the pathology of the disease is unknown. A previously established in vivo model of fatigue-damage accumulation shows that increased apoptosis is correlated with the severity of induced tendon damage, even in early onset of the disease, supporting its implication in the pathogenesis of the disease. Consequently, this study aimed to determine: (1) whether apoptosis could be inhibited after fatigue damage and (2) whether its inhibition could lead to remodeling of the extracellular matrix (ECM) and pericellular matrix (PCM), to ultimately improve …

Electrotransfer Of Different Control Plasmids Elicits Different Antitumor Effectiveness In B16.F10 Melanoma, Masa Bosnjak, Tanjo Jesenko, Urska Kamensek, Gregor Sersa, Jaka Lavrencak, Loree Heller, Maja Cemazar

Bioelectrics Publications

Several studies have shown that different control plasmids may cause antitumor action in different murine tumor models after gene electrotransfer (GET). Due to the differences in GET protocols, plasmid vectors, and experimental models, the observed antitumor effects were incomparable. Therefore, the current study was conducted comparing antitumor effectiveness of three different control plasmids using the same GET parameters. We followed cytotoxicity in vitro and the antitumor effect in vivo after GET of control plasmids pControl, pENTR/U6 scr and pVAX1 in B16.F10 murine melanoma cells and tumors. Types of cell death and upregulation of selected cytosolic DNA sensors and cytokines were …

Screening Of Novel Active Salicylic Acid Analogs And Identification Of A Bacterial Effector Targeting Key Proteins Involved In Salicylic Acid-Mediated Defense, Ian Palmer

Theses and Dissertations

The master regulator of salicylic acid (SA)-mediated plant defense, NPR1 (NONEXPRESSER OF PR GENES 1), and its paralogs NPR3 and NPR4 act as SA receptors. After the perception of a pathogen, plant cells produce SA in the chloroplast. In the presence of SA, NPR1 protein is reduced from oligomers to monomers, and translocated into the nucleus. There, NPR1 binds to TGA and WRKY transcription factors to induce expression of plant defense genes. EDS1 and PBS3 are two key proteins involved in SA biosynthesis. Previous research has shown that several plant pathogens produce SA hydroxylases. These pathogen-produced hydroxylases act to degrade …

Regulation Of Pituitary Progenitor Differentiation By Β-Catenin, Julie Leann Youngblood

Theses and Dissertations

The pituitary gland is a critical organ that is necessary for many physiological processes, including growth, reproduction, and stress response. These vital processes are regulated through the secretion of pituitary hormones from specialized cell types. Pituitary hormone-producing cells arise from a common pool of pituitary progenitors in the developing Rathke’s pouch, and mutations that disrupt the formation and differentiation of pituitary progenitors often result in hypopituitarism, pituitary adenomas, or craniopharyngiomas. Thus, it is necessary to determine the mechanisms of pituitary development in order to understand the ways in which these congenital defects and tumors develop and disrupt pituitary function. Canonical …

Modulation Of Amyloid-Β Aggregation Via Small Molecules And Glycine Zipper Alterations, Steven Zebulon Vance

Theses and Dissertations

Alzheimer’s disease (AD) is the most common form of neurodegenerative disease. Nationally, AD is the 6th leading cause of death and the only top 10 killer of Americans that cannot be slowed, cured, or prevented. AD is characterized by the deposition of extracellular plaques of aggregated amyloid-β protein (Aβ). Aβ originates from the amyloid precursor protein (APP), a transmembrane protein that is cleaved to form a short and inert protein fragment called Aβ. However, Aβ undergoes a nucleation process wherein aggregates from soluble oligomers to insoluble fibrils are formed. While uncertainty remains as to the exact mechanism, studies have associated …

The Visual Ecology Of Speyeria Mormonia, Natalie Sanchez Gonzalez

Theses and Dissertations

Variations in environmental factors such as temperature, precipitation, and day length during larval development are known to affect morphological traits in butterflies related to their visual ecology, including eye size and wing color. These vision-related traits are important for the ability of diurnal butterfly species to detect mates, especially at long distances. Thus, changes in environmental conditions may result in phenotypic modifications to butterflies which may alter their visual ecology and subsequently, their reproductive fitness. To study the interaction of phenotypic plasticity and visual ecology in the Mormon Fritillary, Speyeria mormonia, I set up a natural-laboratory experiment at the Rocky …

A Comprehensive Reengineering Of The Hospital Emergency Triage System, Nicholas D. Boltin

Theses and Dissertations

Hospital emergency triage and specifically Mass Casualty Incidents (MCIs) are of major concern with regard to treatment and patient outcomes. Traditional emergency department triage models are oversimplified and often lead to over/under triaging of patients. Furthermore, triage models do not account for the full spectrum of different types of MCIs which often results in misclassification. In this thesis, we begin by looking at traditional triage models currently being used in hospital systems and identify several shortcomings of using these models within the context of a chemical related MCI. I will then move to describe a new approach to creating a …

Computational Modeling Of Transcatheter Aortic Valves, Mostafa Abbasi

Electronic Theses and Dissertations

Transcatheter aortic valve replacement (TAVR) is an established therapy alternative to surgical valve replacement in high-risk and intermediate-risk patients with severe aortic stenosis. Currently, although TAVR is an alternative and less-invasive treatment for high-risk and intermediate-risk patients, surgical aortic valves replacement (SAVR) was still considered as the gold standard for low-risk patients. TAVR could potentially be applied to lower-risk younger patients if the indications can be safely expanded to the patients and transcatheter aortic valve (TAV) long-term durability can match with that of surgical bioprostheses. In contrast to surgical aortic valves (SAVs), there have been limited clinical data on the …

Knockdown Of Heparan Sulfate Via Ndst1 Knockout Does Not Inhibit Mouse Aortic Endothelial Cell Alignment In-Vivo, John Diaz De Leon Iii

Dissertations and Theses

Atherosclerotic plaque localizes in predictable areas such as arches and bifurcations which are characterized by disturbed flow patterns and the resulting damage and dysfunction to the endothelium. Endothelial cells (ECs) under sustained laminar flow align in the direction of flow; however, under disturbed flow conditions, ECs sustain damage to their glycocalyx (GCX) which results in unaligned and rounder cells. An investigation into the role of NDST1 sulfation of heparan sulfate (HS), a key component of many proteoglycans which make up the GCX, was conducted. The descending aortas (DAs) of transgenic mice with conditional knockouts (KOs) of NDST1 in vascular ECs …

Developing A 3d In Vitro Model By Microfluidics, Hung-Ta Chien

Dissertations and Theses

In vitro tissue models play an important role in providing a platform that mimics the realistic tissue microenvironment for stimulating and characterizing the cellular behavior. In particular, the hydrogel-based 3D in vitro models allow the cells to grow and interact with their surroundings in all directions, thus better mimicking in vivo than their 2D counterparts. The objective of this thesis is to establish a 3D in vitro model that mimics the anatomical and functional complexity of the realistic cancer microenvironment for conveniently studying the transport coupling in porous tissue structures. We pack uniform-sized PEGDA-GelMA microgels in a microfluidic chip to …

Matrix Stiffness Modulates Mesenchymal Stem Cell Sensitivity To Geometric Asymmetry Signals, Maria Eugenia Piroli

Theses and Dissertations

Human stem cells hold significant potential for the treatment of various diseases. However, their use as a therapy is hampered by the limited understanding of the mechanisms by which stem cells respond to environmental stimuli. Efforts to understand extracellular biophysical cues have demonstrated the critical roles of geometric and mechanical signals in determining the fate of stem cells. The goal of this study was to explore the interplay between cell polarity and matrix stiffness in stem cell lineage specification. We hypothesize that confining cells to asymmetric extracellular matrix (ECM) islands will impart polarity at a single-cell level and result in …

Plants As Biofactories To Produce Mammalian Tumor Suppressor Micrornas, John Lachlan Macarthur

Theses and Dissertations

MicroRNAs (miRNAs) are small noncoding single stranded RNAs that are considered master regulators of gene expression. They are also an emerging class of therapeutic agents with significant potential for the prevention and treatment of many diseases, including cancer. Many different forms of cancer are associated with loss or reduced accumulation of one or more miRNAs that function as tumor suppressors. In animal models, restoration of missing tumor suppressor miRNAs prevents the initiation, progression and/or spread of the disease. However, the current absence of an efficient method for delivery of therapeutic miRNAs is a critical barrier to their use. The research …

Coupling Of Mechanical And Electromagnetic Fields Stimulation For Bone Tissue Engineering, Alyaa I. Aldebs

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Alternative bone regeneration strategies that do not rely on harvested tissue or exogenous growth factors and cells are badly needed. However, creating living tissue constructs that are structurally, functionally and mechanically comparable to the natural bone has been a challenge so far. A major hurdle has been recreating the bone tissue microenvironment using the appropriate combination of cells, scaffold and stimulation to direct differentiation. This project presents a bone regeneration formulation that involves the use of human adipose-derived mesenchymal stems cells (hASCs) and a 3D scaffold based on a self-assembled peptide hydrogel doped with superparamagnetic nanoparticles (NPs). Osteogenic differentiation of …

การเตรียมโครงเลี้ยงเซลล์จากไฟโบรอินไหมไทยและไบโอแอคทีฟกลาสเพื่องานวิศวกรรมเนื้อเยื่อกระดูก, พิมพ์นารา วัฒนะชัย

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อเตรียมโครงเลี้ยงเซลล์สำหรับงานวิศวกรรมเนื้อเยื่อกระดูก โดยใช้ไฟโบรอินไหมไทย (SF) และไบโอแอคทีฟกลาส (BG) เชื่อมขวางด้วย 3-ไกลซิดอกซีโพรพิลไตรเอทอกซีไซเลน ((3-Glycidoxypropyl)trimethoxysilane; GPTMS) และขึ้นรูปด้วยวิธีโฟมมิง (Foaming) ผลการวิเคราะห์โครงสร้างทางเคมีด้วยเทคนิค FTIR ยืนยันการเชื่อมขวางระหว่าง SF และ BG เมื่อทดสอบการรับแรงกด พบว่าโครงเลี้ยงเซลล์ผสม SF-BG มีมอดูลัสการกดเพิ่มขึ้นจากโครงเลี้ยงเซลล์ SF ถึง 11 เท่า และไม่มากเกินมอดูลัสของกระดูกจริงดังเช่นโครงเลี้ยงเซลล์ BG ทั้งนี้เสถียรภาพของโครงเลี้ยงเซลล์ผสมที่เชื่อมขวางทั้งสภาวะในน้ำหรือในสารละลายเอนไซม์โปรติเอส XIV ดีกว่าเสถียรภาพของโครงเลี้ยงเซลล์ SF และโครงเลี้ยงเซลล์ผสมที่ไม่ผ่านการเชื่อมขวาง เมื่อทดสอบความไม่เป็นพิษต่อเซลล์ตาม ISO 10993 part 5 พบว่าโครงเลี้ยงเซลล์ผสมไม่มีความเป็นพิษ และผลการทดสอบฤทธิ์ชีวภาพในห้องปฏิบัติการโดยใช้เซลล์กระดูก (SaOS-2 cell line) พบว่าโครงเลี้ยงเซลล์ผสมมีความสามารถในการส่งเสริมการสร้างกระดูก เมื่อพิจารณาจากผลการยึดเกาะ การเจริญเติบโต ระดับกิจกรรมของเอนไซม์แอลคาไลน์ฟอสฟาเตส ปริมาณแคลเซียมที่สะสมภายในเซลล์ และปริมาณแคลเซียมที่ตกตะกอนลงบนโครงเลี้ยงเซลล์ ดังนั้นโครงเลี้ยงเซลล์ผสมชนิดใหม่จาก SF และ BG มีศักยภาพในการใช้เป็นโครงเลี้ยงเซลล์สำหรับงานวิศวกรรมทางเนื้อเยื่อต่อไปในอนาคต

Divergent Scaling Of Miniature Excitatory Post-Synaptic Current Amplitudes In Homeostatic Plasticity, Amanda L. Hanes

Browse all Theses and Dissertations

Synaptic plasticity, the ability of neurons to modulate their inputs in response to changing stimuli, occurs in two forms which have opposing effects on synaptic physiology. Hebbian plasticity induces rapid, persistent changes at individual synapses in a positive feedback manner. Homeostatic plasticity is a negative feedback effect that responds to chronic changes in network activity by inducing opposing, network-wide changes in synaptic strength and restoring activity to its original level. The changes in synaptic strength can be measured as changes in the amplitudes of miniature post-synaptic excitatory currents (mEPSCs). Together, the two forms of plasticity underpin nervous system functions such …

Comparison Of Artificial Saliva Vs Saline Solution On Rate Of Suture Degradation In Oropharyngeal Surgery, Jenna W. Briddell, Luke Riexinger, Jove Graham, Donna M. Ebenstein

Faculty Journal Articles

IMPORTANCE Absorbable sutures are designed to degrade and lose strength over time. Manufacturers warn that exposure to various body fluids can change the estimated degradation rate of these sutures, but few studies have been conducted to quantify the degree of change associated with saliva.

OBJECTIVE To quantify the association of increased loss of strength of sutures over time after exposure to artificial saliva (hereinafter referred to as “saliva”).

DESIGN, SETTING, AND PARTICIPANTS This experimental in vitro study was conducted at Bucknell University (Lewisburg, Pennsylvania) from June 19, 2015, to July 4, 2015. No participants were involved. The loss of strength …

Mimicking Blood Rheology For More Accurate Modeling In Benchtop Research, Lindsey Webb

Honors Undergraduate Theses

To confirm computer simulations and Computational Fluid Dynamics (CFD) analysis, benchtop experiments are needed with a fluid that mimics blood and its viscoelastic properties. Blood is challenging to use as a working fluid in a laboratory setting because of health and safety concerns. Therefore, a blood analogue is necessary to perform benchtop experiments. Viscosity is an important property of fluids for modeling and experiments. Blood is a shear thinning fluid, so it has a decreasing viscosity with higher shear rates. This project seeks to create a blood mimicking fluid for benchtop laboratory use. Numerous fluids with different combinations of water, …

Thermoresponsive, Redox-Polymerized Cellulosic Hydrogels Undergo In Situ Gelation And Restore Intervertebral Disc Biomechanics Post Discectomy, Devika Varma, H. A. Lin, R. G. Long, G. T. Gold, A. C. Hecht, J. C. Iadridis, Steven B. Nicoll

Publications and Research

Back and neck pain are commonly associated with intervertebral disc (IVD) degeneration. Structural augmentation of diseased nucleus pulposus (NP) tissue with biomaterials could restore degeneration-related IVD height loss and degraded biomechanical behaviors; however, effective NP replacement biomaterials are not commercially available. This study developed a novel, crosslinked, dual-polymer network (DPN) hydrogel comprised of methacrylated carboxymethylcellulose (CMC) and methylcellulose (MC), and used in vitro, in situ and in vivo testing to assess its efficacy as an injectable, in situ gelling, biocompatible material that matches native NP properties and restores IVD biomechanical behaviors. Thermogelling MC was required to enable consistent and timely …

Nanopulse Stimulation (Nps) Induces Tumor Ablation And Immunity In Orthotopic 4t1 Mouse Breast Cancer: A Review, Stephen J. Beebe, Brittany P. Lassiter, Siqi Guo

Bioelectrics Publications

Nanopulse Stimulation (NPS) eliminates mouse and rat tumor types in several different animal models. NPS induces protective, vaccine-like effects after ablation of orthotopic rat N1-S1 hepatocellular carcinoma. Here we review some general concepts of NPS in the context of studies with mouse metastatic 4T1 mammary cancer showing that the postablation, vaccine-like effect is initiated by dynamic, multilayered immune mechanisms. NPS eliminates primary 4T1 tumors by inducing immunogenic, caspase-independent programmed cell death (PCD). With lower electric fields, like those peripheral to the primary treatment zone, NPS can activate dendritic cells (DCs). The activation of DCs by dead/dying cells leads to increases …

Adrenergic Stimulation In Acute Hyperglycemia: Effects On Cellular And Tissue Level Murine Cardiac Electrophysiology, Sridevi Thyagarajan

Theses and Dissertations--Biomedical Engineering

Cardiovascular complications associated with elevated levels of glucose in the blood (Hyperglycemia, HG) is a growing health concern. HG is known to be associated with a variety of cardiovascular morbidities including higher incidence of electrical disturbances. Although effects of chronic HG have been widely investigated, electrophysiological effects of acute hyperglycemia are relatively less known. Further, hyperglycemic effects on adrenergic response is not widely investigated. We used excised ventricular tissues from mice to record trans-membrane potentials during a variety of pacing protocols to investigate cellular/tissue level electrophysiological effects of acute hyperglycemia and adrenergic stimulation (1µM Isoproterenol, a β-adrenergic agonist). A custom …

Effects Of Lumbar Spinal Fusion On Lumbopelvic Rhythm During Activities Of Daily Living, Cameron G. Slade

Theses and Dissertations--Biomedical Engineering

Abnormalities in lumbopelvic rhythm (LPR) play a role in occurrence/recurrence of low back pain (LBP). The LPR before spinal fusion surgery and its changes following the surgery are not understood. A repeated measure study was designed to investigate timing and magnitude aspects of LPR in a group of patients (n = 5) with LBP before and after a spinal fusion surgery. Participants completed a forward bending and backward return task at their preferred pace in the sagittal plane. The ranges of thoracic and pelvic rotations and lumbar flexion (as the magnitude aspects of LPR) as well as the mean absolute …

Multimodal Noncontact Diffuse Optical Reflectance Imaging Of Blood Flow And Fluorescence Contrasts, Daniel Irwin

Theses and Dissertations--Biomedical Engineering

In this study we design a succession of three increasingly adept diffuse optical devices towards the simultaneous 3D imaging of blood flow and fluorescence contrasts in relatively deep tissues. These metrics together can provide future insights into the relationship between blood flow distributions and fluorescent or fluorescently tagged agents. A noncontact diffuse correlation tomography (ncDCT) device was firstly developed to recover flow by mechanically scanning a lens-based apparatus across the sample. The novel flow reconstruction technique and measuring boundary curvature were advanced in tandem. The establishment of CCD camera detection with a high sampling density and flow recovery by speckle …

Sleep And Thermoregulation: A Study Of The Effect Of Ambient Temperature Manipulation On Mouse Sleep Architecture, Asma'a A. Ajwad

Theses and Dissertations--Biomedical Engineering

Good quality sleep is essential for mental and physical health. Inadequate sleep impacts memory consolidation, learning and cognition, immune function, autonomic regulation, physical performance, and other vital functions. In many neurological disorders that are associated with sleep problems such as epilepsy and Alzheimer’s disease, changes in brain circuitry affect sleep-wake regulation mechanisms; this is reflected in anomalous sleep-wake architecture and usually accompanied by poor sleep depth. Thus, over many years, many approaches have been tried in humans and animal models with the goal of improving sleep quality. Unfortunately, each of those approaches comes with limitations or side effects. Thus, there …