Biomedical Engineering and Bioengineering Commons^™

Adenovirus Co-Opts Neutrophilic Inflammation In Order To Enhance Entry Into Epithelial Cells, James Matthew Readler

Browse all Theses and Dissertations

Human adenoviruses (AdV) are double-stranded DNA viruses that can cause a range of diseases. While AdV respiratory infections are often mild and self-limited, severe manifestations such as fulminant pneumonia and acute respiratory distress syndrome (ARDS) are not uncommon. In order to identify potential modalities to treat AdV infections and potentially enhance the effectiveness of AdV vector delivery, a thorough mechanistic understanding of how AdV enters host cells is needed. Previous studies have revealed polarized epithelia, one of the primary targets for AdV respiratory infections, are highly resistant to AdV entry from the apical (luminal) surface. However, upon exposure to interleukin …

Quantification Of Optical Parameters Using Frequency Domain Functional Near-Infrared Spectroscopy (Fd-Fnirs), Christopher W. Davies

Browse all Theses and Dissertations

Near infrared spectroscopy (NIRS) is a non-invasive technique that uses near-infrared light and hemoglobin as the contrast to characterize tissue optical properties, namely optical absorption [����] and scattering [����′ ]. Through this characterization, it is possible to obtain information about the tissue’s oxygenated (HbO) and deoxygenated (Hb) hemoglobin concentrations and oxygen saturation which are important physiological markers for diagnosis and intervention monitoring. Many commercial devices use a continuous wave approach (CW-fNIRS), a technique that simply relies on intensity changes from a constant power laser to determine only relative changes in oxygenation. This is a significant limitation for clinical settings where …

Rescue Of Als Protein Fus Toxicity By Taf, Elliott Hayden

Browse all Theses and Dissertations

Amyotrophic Lateral Scleroses (ALS) is a neurodegenerative disease characterized by the degeneration of upper and lower motor neurons in the brain and spinal cord leading to progressive paralysis and ultimately death within 5 years of symptom onset. Only two drugs are approved by the Food and Drug Administration (FDA) for treating ALS that slow the disease progression by about 3 months. Mutations in the gene Fused in Sarcoma (FUS) cause inherited forms of ALS. FUS is a nuclear, multifunctional RNA-binding protein (RBP) involved in multiple RNA metabolic pathways. Mutations in FUS cause mislocalization of the protein from the nucleus to …

Mechanical Stresses On Nasal Mucosa Using Nose-On-Chip Model, Zachary Edward Brooks

Browse all Theses and Dissertations

The objective of this research was to design and fabricate a nose-on-chip device and bi-directional airflow system that models flow within the nasal cavity to investigate how airflow induced mechanical stresses impact nasal secretion rates and cytoskeletal remodeling. This research hypothesizes that the airflow induced shear stresses on the nasal mucosa will influence mucus production and the cytoskeleton of the cells. The RPMI 2650 cell line was used to model the nasal mucosa. The system was used to replicate the wall shear stresses (WSS) and wall shear forces (WSF) present in the anterior region of the nose. The WSS and …

Monitoring Cerebral Functional Response Using Scmos-Based High Density Near Infrared Spectroscopic Imaging, Dharminder Singh Langri

Browse all Theses and Dissertations

Neurovascular coupling is an important concept that indicates the direct link between neuronal electrical firing with the vascular hemodynamic changes. Functional Near Infrared Spectroscopy (fNIRS) can measure changes in cerebral vascular parameters of oxy-hemoglobin and deoxyhemoglobin concentrations and thus can provide neuronal activity through neurovascular coupling. Currently many commercial fNIRS devices are available, but they are limited by the number of channels (usually having only 8 detectors), which can limit the sensitivity, contrast, and resolution of imaging. High-density imaging can improve sensitivity, contrast, and resolution by providing many measurements and averaging the signals originating from the target cerebral focus area …

Differential Microrna Expression In Barrett's Esophagus Correlates With Regulation Of Posterior Homeotic Genes, Reilly June Clark

Browse all Theses and Dissertations

Barrett’s Esophagus (BE) is characterized by the appearance of an intestinal-like epithelium in the distal esophagus. The molecular mechanisms behind BE development are unknown. BE is often preceded by Gastroesophageal Reflux Disease (GERD) and predisposes patients to esophageal adenocarcinoma (EAC). Due to the high mortality rate associated with EAC, BE patients are continuously monitored through upper endoscopy with biopsy for progression to low grade dysplasia (LGD), high grade dysplasia, and EAC. This monitoring technique poses numerous risks, so alternative surveillance and diagnostic techniques for BE pathogenesis are continually studied. microRNA biomarkers in BE pathogenesis may provide alternative means of diagnosis …

Type 2 Diabetes Leads To Impairment Of Cognitive Flexibility And Disruption Of Excitable Axonal Domains In The Brain, Leonid M. Yermakov

Browse all Theses and Dissertations

Type 2 diabetes is a metabolic disease affecting millions of people around the world. Cognitive and mood impairments are among its many debilitating complications, but disease mechanism(s) remain elusive. Here, we present a series of behavioral tasks that demonstrate impairment of cognitive flexibility in db/db mice, a commonly used type 2 diabetes model. Using immunohistochemistry, we demonstrate disruption of axon initial segments (AIS) and nodes of Ranvier, excitable axonal domains regulating neuronal output, in brain regions associated with cognitive and mood impairments. Finally, we present results of exercise treatment that ameliorates AIS disruption in these animals. Establishing cognitive flexibility deficits …

Computational Simulation Of A Femoral Nail Fracture, Stephen Charles Whatley

Browse all Theses and Dissertations

Every year in the United States roughly 300,000 people over the age of 65 suffer from a hip fracture. Ninety five percent of which are the result from a fall. The resulting hip fracture can be classified into several categories of fracture. Depending on the damage the patient could be implanted with a femoral nail device to assist in their recovery. These devices can, however, have complications during recovery. In some cases, these nails can have a failure rate as high as 10%. When failure occurs, extensive investigations are needed to determine the causes of failure. These investigations involve physical …

Chondroitin Sulfate Hydrogels For Total Wound Care Devices, Tushar Goswami

Browse all Theses and Dissertations

Chondroitin sulfate (CS) is a naturally occurring bio-polymer found in areas of high cartilage in mammals. In directed applications, such as hydrogels, CS can be used to impact keratinocyte growth cycles. In this work, CS based hydrogels were utilized to accelerate wound healing and, in conjunction with a graphene sensor, monitor wound fluid pH. The hydrogels were cast onto a graphene field effect transistor (GFET) to obtain the benefits of the hydrogel wound healing capabilities, while also utilizing the pH sensitivity of the graphene. Results showed that the hydrogel caused a fivefold increase in cell size over the course of …

Characterizing Basal-Like Triple Negative Breast Cancer Using Gene Expression Analysis: A Data Mining Approach, Qamar Alsabi

Browse all Theses and Dissertations

Triple-negative breast cancer (TNBC) is characterized by the absence of expression of the estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (HER2). Therefore, TNBC is unresponsive to targeted hormonal therapies, which limits treatment options to nonselective chemotherapeutic agents. Basal-like breast cancers (BLBCs) represent a subset of about 70% of TNBCs, more frequently affecting younger patients, being more prevalent in African-American women and significantly more aggressive than tumors of other molecular subtypes, with high rates of proliferation and extremely poor clinical outcomes. Proper classification of BLBCs using current pathological tools has been a major challenge. Although TNBCs have …

Feature-Based Discretization Of A Turbine Disk For Probabilistic Risk Assessment, Michael Thomas, Jace Carter, Lloyd Matson, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

There is an economic need to extend the useful life of jet engine rotors. Retirement-for-Cause (RFC) is a lifing method that allows for the continued operation of components passed traditional life limits. Under RFC, an extension of damage tolerance, components are deemed safe for a further service interval using non-destructive inspections (NDI) for crack like defe cts. As components are kept in-service beyond their designed service life it is essential that the probability of failure (POF), or risk, of continued service is known. Under current FAA rotor design certification practices the component POF is analyzed using a probabilistic framework focused …

Failure Analysis Of Philos Plate Construct Used For Pantalar Arthrodesis Paper Ii-Screws And Fem Simulations, Farah Hamandi, Richard T. Laughlin, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

A fractured stainless steel 3.5 mm proximal humerus internal locking system (PHILOS) plate and screws were investigated in this paper. This plate was used for ankle arthrodesis of a 68-year-old female with a right ankle deformity. Both the plate and screws were considered in this investigation. Optical and scanning electron microscopes (SEM) were used to document fracture surface characteristics, such as extensive scratching, plastic deformation, rubbed surfaces, discoloration, and pitting, along with cleavage, secondary cracking, deposits of debris, striations, and dimples. Indications of these features show that the plate failed by corrosion fatigue, however, overloading separated the screw(s) in two …

The Pattern Of Sensory Axonal Endings Together With Synaptic Transmission Influence The Development Of Proprioceptive Circuits In The Spinal Cord, Yiyun Dai

Browse all Theses and Dissertations

Proprioceptive circuits provide information regarding limb position and movement status, and are essential to producing correctly executed motor behaviors. Exploring the mechanisms underlying the formation of proprioceptive circuits is therefore critical for understanding neurological disorders with altered motor coordination and for restoring circuits damaged by injury. One important proprioceptive circuit, the stretch reflex circuit, is formed between proprioceptive sensory neurons (PSNs) and motor neurons (MNs) that innervate the same muscle. Progress has been made in understanding the spatial organization of MNs based on their muscle-specific subpopulation identities, which contributes to the specificity of stretch reflex circuit formation. However, whether PSNs …

Electroceutical Therapy In Amyotrophic Lateral Sclerosis: A Novel Preliminary Study, Morgan Michelle Highlander

Browse all Theses and Dissertations

Amyotrophic Lateral Sclerosis (ALS) is a fatal, neurodegenerative disease that is characterized by the death of motoneurons. Life expectancy is only 3-5 years from diagnosis and current treatments only extend survival by 2-3 months. The mechanism of motoneuron death in ALS is still largely unknown, but abnormal motoneuron excitability has been extensively documented. Because the intrinsic excitability of a motoneuron is a defining measure of its normal function, characterizing and regulating motoneuron excitability has become one of the primary aims of ALS research. Although not previously explored in ALS, other clinical applications show the ability of certain electroceutical techniques to …

Regulation Of The Motor Output Of The Spinal Cord: Burst Firing Generation And Sensorimotor Integration, Amr A. Mahrous

Browse all Theses and Dissertations

Spinal motoneurons are the final common path for motor signals. Thus, the firing activity recorded from spinal motoneurons or their axons in the ventral roots represents the motor output of the nervous system. This dissertation investigates two major phenomena that help generate and shape the neuronal motor output. Specialized groups of spinal neurons called central pattern generators (CPGs) are capable of orchestrating rhythmic bursting activity without involvement of the brain. This activity underlies stereotyped movements such as locomotion. If known, the ionic mechanisms responsible for generating this activity can offer new pharmacological interventions to restore walking in paralyzed patients with …

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 …

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

Browse all Theses and Dissertations

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 …

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 …

A Novel Approach For Cancer Characterization Using Latent Dirichlet Allocation And Disease-Specific Genomic Analysis, Hima Bindu Yalamanchili

Browse all Theses and Dissertations

Two challenging problems in the clinical study of cancer are the characterization of cancer subtypes and the classification of individual patients according to those subtypes. Further, understanding the role of differential gene expression in the development of and molecular response to cancer is a complex problem that remains challenging, in part due to the sheer number of genes and gene products involved. Traditional statistical approaches addressing these problems are hindered by within-class heterogeneity and challenges inherent in data integration across high-dimensional data. In addition, many current machine learning methods do not lend themselves to biological interpretation. We have developed a …

M1 To M2 Macrophage Induction Using Retinoic Acid And Mesenchymal Stem Cells Loaded On An Electrospun Pullulan/Gelatin Scaffold To Promote Healing Of Chronic Wounds, Kaivon Assani

Browse all Theses and Dissertations

Modulation of macrophage polarization is required for effective tissue repair and regenerative therapies. Conversion of macrophages from inflammatory M1 to fibrotic M2 phenotype could help in diseases such as chronic wound which are stuck in inflammatory state. During the inflammatory phase, macrophages are of the inflammatory phenotype (M1) and distribute pro-inflammatory cytokines including TNF-a and IL1[beta] which are microbicidal and recruit/activate cells. In normal wound healing macrophages then switch to a fibrotic phenotype (M2) promoting wound closure by angiogenesis, and matrix deposition. Chronic wounds are a major biological and financial burden to both patients and the health care system, costing …

Effect Of Dimensionality On In Vitro Growth Environment And Mesenchymal Stem Cell Function, Fatema Tuj Zohora

Browse all Theses and Dissertations

The use of the standard two dimensional (2D) cell culture has laid down the fundamentals of molecular and cell biology. However, recent advances in cell-based regenerative medicine raises the concern on deconstructing cellular behaviors in more physiologically relevant three dimensional (3D) microenvironments. Differences in cell response in 2D versus 3D systems arise from the perturbations in gene expression patterns that stem from how cells sense their underlying 2D or surrounding 3D matrices and adjust their phenotypes accordingly. Thus, cells are no longer considered as a solitary entity of genome but a context arises from a combinatorial interactions of cell-ECM, cell-cell, …

Novel Auto-Calibrating Neural Motor Decoder For Robust Prosthetic Control, Andrew Earl Montgomery

Browse all Theses and Dissertations

The overarching goal of this project is to develop novel neural motor decoders for prosthetic control. EMG decoders measure the activity from an intact but non-target muscle. Neural motor decoders transform the signal measured from the severed motor axons of the target muscle. A multi-scale, highly-realistic computer model of a spinal motor pool was developed (Allen & Elbasiouny, 2018) to serve as a computational platform for decoder development and testing. A firing rate-based algorithm was developed to transform the aggregate discharge of the motor pool into a command signal to control the simulated prosthetic MuJoCo hand. This algorithm was informed …

Utilizing Functional Near-Infrared Spectroscopy For Prediction Of Cognitive Workload In Noisy Work Environments, Ryan Gabbard, Mary E. Fendley, Irfaan A. Dar, Rik Warren, Nasser H. Kashou

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Occupational noise frequently occurs in the work environment in military intelligence, surveillance, and reconnaissance operations. This impacts cognitive performance by acting as a stressor, potentially interfering with the analysts’ decision-making process. We investigated the effects of different noise stimuli on analysts’ performance and workload in anomaly detection by simulating a noisy work environment. We utilized functional near-infrared spectroscopy (fNIRS) to quantify oxy-hemoglobin (HbO) and deoxy-hemoglobin concentration changes in the prefrontal cortex (PFC), as well as behavioral measures, which include eye tracking, reaction time, and accuracy rate. We hypothesized that noisy environments would have a negative effect on the participant in …

Macrodamage Accumulation Model For A Human Femur, Farah Hamandi, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

The objective of this study was to more fully understand the mechanical behavior of bone tissue that is important to find an alternative material to be used as an implant and to develop an accurate model to predict the fracture of the bone. Predicting and preventing bone failure is an important area in orthopaedics. In this paper, the macrodamage accumulation models in the bone tissue have been investigated. Phenomenological models for bone damage have been discussed in detail. In addition, 3D finite element model of the femur prepared from imaging data with both cortical and trabecular structures is delineated using …

Human Biomechanics Ii Course Project, Abdelaziz Mohammad

Best Integrated Writing

Mohammad tested Human Arm Module PASCO ME-6807A, in order to determine some of the biomechanical characteristics, such as force, tension, instantaneous angular velocity, and acceleration vs. angular position required for various movements and arm positions in space.

Brain Lesions Among Orally Fed And Gastrostomy-Fed Dysphagic Preterm Infants: Can Routine Qualitative Or Volumetric Quantitative Magnetic Resonance Imaging Predict Feeding Outcomes?, Nasser H. Kashou, Irfaan Akram Dar, Mohamed A. El-Mahdy, Charles Pluto, Mark Smith, Ish K. Gulati, Warren Lo, Sudarshan R. Jadcherla

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Introduction: The usefulness of qualitative or quantitative volumetric magnetic resonance imaging (MRI) in early detection of brain structural changes and prediction of adverse outcomes in neonatal illnesses warrants further investigation. Our aim was to correlate certain brain injuries and the brain volume of feeding-related cortical and subcortical regions with feeding method at discharge among preterm dysphagic infants.

Materials and methods: Using a retrospective observational study design, we examined MRI data among 43 (22 male; born at 31.5 ± 0.8 week gestation) infants who went home on oral feeding or gastrostomy feeding (G-tube). MRI scans were segmented, and volumes of brainstem, …

Context-Dependence Of Physiological Systems: Environment-Physiology Interactions In The Respiratory Control System, Joseph M. Santin

Browse all Theses and Dissertations

We know that animals are tuned to survive different environmental conditions or else life would not exist. Unfortunately, this is often forgotten or ignored when designing experiments. As Marsh Tenney articulated, "The physiologist keeps the whole always in mind. He accepts the tactical necessity of reductionism to understand parts, but, once done, for him it is only the beginning, never the end” (from Remmers, 2005). In an era when it is all too common to take environmental complexity out of the organism to understand physiology, my work puts some of that complexity back in the study of organisms. I take …

Probabilistic Analysis Of Wear Of Polymer Material Used In Medical Implants, V. Perel, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Probabilistic methods are applied to the study of fatigue wear of sliding surfaces. A variance of time to failure (to occurrence of maximum allowable wear depth) is evaluated as a function of a mean wear rate of normal wear and a size of wear particles. A method of estimating probability of failure-free work during a certain time interval (reliability) is presented. An effect of the bedding-in phase of wear on the reliability is taken into account. Experimental data for Ultra High Molecular Weight Polyethylene (UHMWPE) cups of artificial hip implants is used to make numerical calculations.

Regulation Of The Expression And Activity Of Extracellular Signal-Regulated Kinase 3 (Erk3), Lobna Elkhadragy

Browse all Theses and Dissertations

Mitogen-activated protein kinases (MAPKs) are Ser/Thr kinases that regulate diverse cellular processes. Extracellular signal-regulated kinase 3 (ERK3) is an atypical MAPK that has recently gained interest for its roles in cancer. ERK3 promotes cancer cell migration, invasion and drug resistance, and its expression is upregulated in multiple cancers. However, little is known about the molecular mechanisms that regulate ERK3’s expression and kinase activity. Here, we have identified the oncogenic polycomb group protein BMI1 as a positive regulator of ERK3 level in cancer cells. Mechanistically, BMI1 upregulates ERK3 expression by inhibiting the expression of the tumor suppressor microRNA (miRNA) let-7i, which …

Glycolytic Metabolism And Pregnancy Parameters In The Murine Placenta, Renee Elizabeth Albers

Browse all Theses and Dissertations

The placenta is a complex and essential organ composed largely of fetal-derived cells, including several different trophoblast subtypes that work in unison to support nutrient transport to the fetus during pregnancy. Abnormal placental development can lead to pregnancy-associated disorders that often involve metabolic dysfunction. The scope of dysregulated metabolism during placental development may not be fully representative of the in vivo state in defined culture systems, such as cell lines or isolated primary cells. Thus, assessing metabolic function in intact placental tissue would provide a better assessment of placental metabolism. In this study, we describe a methodology for assaying glycolytic …