Biomedical Engineering and Bioengineering Commons^™

Development Of A Wearable Short-Wave Infrared Photoplethysmography Device For Detection And Monitoring Of Hemodilution During Postpartum Hemorrhage, Hannah Gruensfelder

McKelvey School of Engineering Graduate Student Theses & Dissertations

ABSTRACT OF THE THESIS

A Thesis on the Development of a Wearable Short-Wave Infrared Photoplethysmography Device for Detection and Monitoring of Hemodilution During Postpartum Hemorrhage

by

Hannah Gruensfelder

Master of Science in Biomedical Engineering

Washington University in St. Louis, 2024

Professor Christine O’Brien, Chair

Postpartum hemorrhage (PPH), the leading cause of maternal death and morbidity, affects nearly 14 million people worldwide each year, disproportionally impacting racial minorities and people in low resource settings. A timely diagnosis of PPH is key in providing optimal patient care, as an estimated 90% of deaths due to PPH are preventable with early diagnosis and …

Transcriptomic Profiling Of Engineered Human Gene Integration In The Mouse Genome Following In Vitro Gene Editing, Ethan Potts, Made Harumi Padmaswari, Christopher Nelson

Biomedical Engineering Undergraduate Honors Theses

Gene replacement is a promising method of therapy for genetic diseases. However, safety and efficacy are areas that need more research. This experiment aims to use RNA sequencing and bioinformatic techniques to provide answers to these questions and provide direction to future studies to develop a gene replacement therapeutic. C2C12 mouse myoblast cells were transfected with a vector containing a CRISPR-Cas9 system and the Human Factor IX (hF9) gene in order to hijack target genes and integrate the hF9 gene. The two target genes, myoglobin (Mb) and creatine kinase (Ckm), were chosen for their high rate of expression and low …

Real-Time Measurements From Wearable Sensors To Enhance Stability On Uneven Terrain, Sophie Copelin

Biomedical Engineering Undergraduate Honors Theses

The presented thesis is a study of sensation associated with inversion/eversion movement about the anterior/posterior axis. The long-term goal is to create a system that provides feedback to a prosthesis user, so their chances of falling is decreased. This feedback system would use wearable sensors to detect certain angles, so that sensory feedback could be provided. The study aimed to determine if Xsens Movella DOT sensors could be used in a system like this, so the accuracy of the Xsens Movella DOT sensors was assessed and the difference in angles that could be determined by them when compared to that …

Detection Of Hypoxia Via Rgb Imaging, Nathania Nischal

Biomedical Engineering Undergraduate Honors Theses

Colorectal cancer is a common form of cancer, and is heavily researched in murine models. Colonoscopies are often performed in clinical settings to assess the health of the colon, as well as locate and assess the severity of tumors in a non-invasive way. As the quality of the images is dependent on the colonic environment and the light available, it is important to ensure the accuracy of the images via a normalization algorithm. The RGB images procured from these colonoscopies have great potential as a diagnostic tool for physicians, as varying scales of discoloration is common in hypoxic tissue. While …

Dorsal Root Ganglia Neurite Outgrowth Following Traumatic Spinal Cord Injury Repair: A Review, Adrienne Vaughan

Biomedical Engineering Undergraduate Honors Theses

Traumatic spinal cord injury (tSCI) can cause partial sensorimotor deficiency or total dysfunction, rendering patients unable to perform necessary tasks and dramatically decreasing their quality of life. tSCI is a very prevalent issue. In the United States alone, there are approximately 54 new cases of SCI per one million people each year, or 18,000 new cases annually. tSCI creates a lesion gap filled with axon-inhibiting fibrotic scar tissue. Comprehensive functional recovery following traumatic spinal cord injury (tSCI) requires axonal regeneration across wound site lesions. Dorsal root ganglia (DRG) neurite outgrowth is often evaluated in PNI therapeutic research since it can …

Computational Predictions Of Heart Failure Drug Effects On Cardiac Fibrosis, Aaron Gardner

Chemical Engineering Undergraduate Honors Theses

The extracellular matrix is a complex system surrounding cells that is crucial to all of the cardiovascular system’s functions. Fibrosis is an excessive accumulation (scarring) of the extracellular matrix. Fibrosis is typically a negative event, and the scarring must be reduced in the heart in order to maintain its functionality. Due to this, simulations are run using the software “Netflux” in order to determine the effects of different heart failure drugs on cardiac fibrosis. The drugs that were simulated were an ACE Inhibitor, BAR Beta Blocker, ARB Blocker, and Entresto. These drugs were simulated over 50 hours at three different …

Modeling Of Nk Cells In Pediatric Patients With Unusually Severe Or Recurrent Hsv Using High-Dimensional Flow Cytometry, Yunran Feng

McKelvey School of Engineering Graduate Student Theses & Dissertations

HSV infection is broadly spread all over the world with some patients having severe and/or recurrent HSV infections. Our lab studies human Natural Killer (NK) cells, which are important in innate immune responses to viral infections and tumors. A publication in 2013 by Ornstein et al from our lab studied HSV+ pediatric patients and found some associations between severe infection and defects in NK cytolytic function. PLCG2 haploinsufficient variants found in 2 HSV patients causing PLCγ2 hypophosphorylation, and loss of cytolytic function in NK cells is a novel finding recently published by Alinger et al from our lab in 2023. …

Controlled Delivery Of Peptide And Gasotransmitter For Promoting Vascular Endothelialization, Shirin Changizi

Theses and Dissertations

Endothelial cells (ECs) are vital for maintaining proper vascular function and regulating processes such as hemostasis and inflammation. Disruption of endothelial cells integrity can lead to several pathological conditions, including coronary artery disease, vascular cognitive impairment, and dementia (VCID). Alterations in ECs distribution may lead to compromised blood-brain barrier (BBB) function, facilitating the passage of blood components and contributing to conditions such as Alzheimer's disease. Additionally, disruptions in ECs function can lead to early-stage thrombosis and intimal hyperplasia, resulting in graft failure in small-diameter (

This study aimed to develop innovative approaches for drug delivery to the BBB and TEVGs …

Analyzing Diverse Student Experiences: The Intersection Of Equity, Inclusivity, And Biomedical Engineering Education Through A Clinical Observations And Needs Finding Course, Jacquelynn Horsey

Biomedical Engineering Undergraduate Honors Theses

In the field of biomedical engineering, needs identification and solution development are an important element of the design process. In our undergraduate curriculum, a course was designed to allow clinical observation and provide an opportunity for students to learn about engineering design and engage with clinicians via completing rotations in medical facilities near our campus. While this type of course is not unique, evaluating its efficacy is not simple. Given the broad range of institutional resources available- such as proximity to a medical school, or residency programs- reporting the quality of such courses within the context of such available resources …

The Determination Of Macrophage Localization In Muscle Injuries Using Spatial Transcriptomics, Julliana Renales

Biomedical Engineering Undergraduate Honors Theses

The repair of traumatic muscle injury is often a long process which can in many cases be insufficient and incomplete. In such cases, scar tissue may form, leading to high risk of re-injury and the prevention of muscle regeneration. An important part of decreasing this risk is gaining a better understanding of the cellular complexities of injury repair. More specifically, macrophage cells are an important piece in the regulation of inflammation and repair. In this project, computational analysis spatial transcriptomic data was performed to examine mouse muscle injury and its development over time. This analysis was used to examine the …

The Effect Of Central Screw And Post Vault Containment On Reverse Total Shoulder Arthroplasty (Rsta) Baseplate Stability, Mickaela J. Gunnison

All Theses

Reverse total shoulder arthroplasty (RTSA) is a procedure that aims to fix irreversible rotator cuff damage and degenerative glenohumeral joint diseases that hinder arm abduction. One major complication of RTSA is glenoid baseplate failure resulting from increased movement at the bone-baseplate interface. This study examined 36, 12 PCF composite Sawbones® scapulae. The specimens were split equally into 6 study groups, each having different implant configurations with varying baseplate lateralization and central screws or posts. Each specimen was subjected to cyclic shear loading and failure testing on an Instron to determine implant micromotion and load values.

After testing, ANOVA tests were …

Light-Induced Phase Separation Purification For Monoclonal Antibodies, Xuyang Chen

All Theses

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Investigation Of Early Stage Wound Healing In Volumetric Muscle Loss, Sean Ong

Biomedical Engineering Undergraduate Honors Theses

Volumetric muscle loss (VML) refers to the substantial removal of tissue from skeletal muscle due to surgery or lesions. This condition disrupts the normal regenerative process of injured muscles, leading to significant loss of muscle function. This study examines the progression of VML injury, approximately 20% of the muscle mass being removed, in the tibialis anterior (TA) muscle of a mouse model over a 15-day post-injury period. The injured muscles exhibited discoloration indicative of reduced blood flow and experienced a decrease in muscle mass throughout the study duration. Furthermore, the maximum force output of the injured TA was significantly lower, …

Biomass Derived Lignin Polymer Modification For Sustainable Chemical Engineering Applications, Samantha Glidewell, Keisha Walters

Chemical Engineering Undergraduate Honors Theses

Lignin is an abundant naturally occurring plant-based polymer that is branched, highly unsaturated, and rich in aliphatic and aromatic hydroxyl groups. Lignin is a significant byproduct of the wood pulp and paper industries; however, it has yet to be widely utilized in commercial applications due to its non-linear structure, broad range of molecular weights, hydrophobicity, high rigidity, and brittleness. Recent investigations into modifying lignin to broaden its potential uses have shown promising results. This thesis explores different modification techniques of the naturally occurring hardwood lignin polymer for specific applications in areas of water treatment and polyurethane (PU) production. The first …

Suppressing Reactive Oxygen Species Via Application Of Antioxidant Supramolecular Polymers, Zacchaeus Wallace

Honors Theses

Cardiovascular diseases along with various other disease conditions are characterized by an upregulation in reactive oxygen species (ROS), which can overwhelm homeostatic processes in the body, resulting in cellular apoptosis and severe oxidative damage. The lack of clinically approved treatments to regulate or alleviate this elevated ROS presence underscores the need for novel therapeutic strategies. While antioxidants promote cell rescue through ROS scavenging, their clinical translation is impeded by insufficient bioavailable concentrations at the source of injury. The opportunity to apply antioxidant supramolecular polymers of peptide amphiphiles (PAs) is an exciting prospect of research to combat corresponding issues. For this …

Mammary Epithelial Cell Derived Extracellular Vesicles Influence Tumorigenic Phenotype Suppression In Her2-Positive Breast Cancer Cells, Brenda Okereke

All Dissertations

On a global scale, breast cancer remains the most commonly diagnosed cancer in the world. In 2020 alone, there were over 2.3 million new cases of breast cancer seen and a total of 685,000 deaths globally, this represents 16% or 1 in every 6 cancer deaths seen in women. By 2040 it is projected that the breast cancer burden will rise by over 40% to exceed 3 million new cases a year. Further understanding of the underlying biology and mechanisms behind tumor progression and breast cancers such as HER2+ breast cancer would allow for new therapeutic treatment targets to emerge. …

Identifying Temporomandibular Disorder Morphological Risk Factors Via Explainable Deep Learning And Multiscale Biomechanical Modeling, Shuchun Sun

All Dissertations

Clarifying multifactorial musculoskeletal disorder etiologies supports risk analysis and development of targeted prevention and treatment modalities. Deep learning enables comprehensive risk factor identification through systematic analysis of disease datasets but does not provide sufficient context for mechanistic understanding, limiting clinical applicability for etiological investigations. Conversely, multiscale biomechanical modeling can evaluate mechanistic etiology within the relevant biomechanical and physiological context. We propose a hybrid approach combining 3D explainable deep learning and multiscale biomechanical modeling; we applied this approach to investigate temporomandibular joint (TMJ) disorder etiology by systematically identifying risk factors and elucidating mechanistic relationships between risk factors and TMJ biomechanics and …

The Role Of Voluntary Descending Control In Enhancing Motor Function Via Transcutaneous Spinal Cord Stimulation, Yoon Kim

McKelvey School of Engineering Graduate Student Theses & Dissertations

Spinal cord injury (SCI) is a life-changing event that causes lasting motor impairments. Transcutaneous spinal cord stimulation (tSCS), a non-invasive form of neuromodulation in which electrodes are placed on the skin and used to stimulate the spinal circuits via an electrical current, has demonstrated positive effects on motor function recovery in individuals who have had SCIs. However, the precise mechanism of how tSCS interacts with voluntary descending drive remains poorly understood. This study aims to investigate the role of voluntary descending control in influencing reflex responses triggered by tSCS.

Electromyography (EMG) recordings were performed in ten unimpaired individuals while they …

Acoustofluidic Delivery Of Biomolecules To Cells: A Novel Approach For Preparing Car-T Cells., Madison C. Colebank

Electronic Theses and Dissertations

The continuous pursuit of effective methods for gene transfection in primary human T cells is crucial for advancing cell-based therapies. Viral vectors, currently used in cell-based therapies, involve a lengthy and costly process. This thesis explores the efficacy of coupling acoustofluidic and sonoporation techniques as an alternative non-viral gene transfection approach with primary T cells. Sonoporation, in conjunction with microbubbles, has been demonstrated to induce cavitation, resulting in the formation of pores in the cell membrane through which molecules can enter. Using flow cytometry, we compared the loading efficiency of primary T cells with that of Jurkat T cells to …

Database And Machine Learning Model For Classifying Autism Spectrum Disorder From Smartphone Based Electroretinography, Rory Harris

Honors Scholar Theses

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder that negatively affects a patient’s cognitive and communication aptitude and, therefore, can severely impact that patient’s quality of life. Because of this, early diagnosis is paramount. In recent studies, electroretinography (ERG), which is a measure of the retina’s electrical response to a brief flash of light into the eye, has shown promise in detecting ASD. Access to these scans can provide early diagnosis, improving well-being. Current ERG devices are very expensive due to their on board processing capabilities. This paper aims to create an ERG device using a smartphone as the main …