Biomedical Engineering and Bioengineering Commons^™

Water Exchange Rate Across The Blood-Brain Barrier Is Associated With Csf Amyloid-Β 42 In Healthy Older Adults, Brian T. Gold, Xingfeng Shao, Tiffany L. Sudduth, Gregory A. Jicha, Donna M. Wilcock, Elayna R. Seago, Danny J. J. Wang

Sanders-Brown Center on Aging Faculty Publications

INTRODUCTION: We tested if water exchange across the blood-brain barrier (BBB), estimated with a noninvasive magnetic resonance imaging (MRI) technique, is associated with cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD) and neuropsychological function.

METHODS: Forty cognitively normal older adults (67–86 years old) were scanned with diffusion‐prepared, arterial spin labeling (DP‐ASL), which estimates water exchange rate across the BBB (k_w). Participants also underwent CSF draw and neuropsychological testing. Multiple linear regression models were run with kw as a predictor of CSF concentrations and neuropsychological scores.

RESULTS: In multiple brain regions, BBB kw was positively associated with CSF amyloid …

Survival And Proliferation Under Severely Hypoxic Microenvironments Using Cell-Laden Oxygenating Hydrogels, Shabir Hassan, Berivan Cecen, Ramon Peña-Garcia, Fernanda R. Marciano, Amir K. Miri, Ali Fattahi, Christina Karavasili, Shikha Sebastian, Hamza Zaidi, Anderson O. Lobo

Henry M. Rowan College of Engineering Departmental Research

Different strategies have been employed to provide adequate nutrients for engineered living tissues. These have mainly revolved around providing oxygen to alleviate the effects of chronic hypoxia or anoxia that result in necrosis or weak neovascularization, leading to failure of artificial tissue implants and hence poor clinical outcome. While different biomaterials have been used as oxygen generators for in vitro as well as in vivo applications, certain problems have hampered their wide application. Among these are the generation and the rate at which oxygen is produced together with the production of the reaction intermediates in the form of reactive oxygen …

Glial Endothelial Brain Cell Co-Cultures For Testing Signaling Response And Delivery Of Novel Materials Across Blood Brain Barrier, Neela Prajapati

Master's Theses

The brain accounts for 20% of overall energy metabolism in the body though it just comprises 2% of the total body mass but has a limited capacity of storing energy unlike other critical organs in the body such as the heart and liver. This energy along with oxygen and nutrients is supplied by cerebral blood flow (CBF), any interruption of which can cease the brain function within seconds with a potential irreversible neuronal injury, within minutes. Vascular cells along with astrocytes and neurons are a part of a recently developed concept known as the Neurovascular Unit responsible for Neurovascular coupling …

Epi-Mucosa Fixation And Autologous Platelet-Rich Fibrin Treatment In Medication-Related Osteonecrosis Of The Jaw, Antonio Cortese, Antonio Casarella, Candace M. Howard, Pier Paolo Claudio

Faculty and Student Publications

Medication-related osteonecrosis of the jaw (MRONJ) frequently affects patients after treatments with bisphosphonates or denosumab, especially with high doses in patients with bone osteoporosis, neoplastic metastases, or possibly anti-angiogenic treatment for cancer. The aim of this article was to show a new treatment planning for stage 2 and stage 3 MRONJ using platelet-rich fibrin (PRF) at the surgical field to enhance healing in association with a new epi-mucosal fixation technique to prevent or treat mandibular fracture. Two cases were treated by epi-mucosa fixation and autologous PRF use for prevention of mandibular fracture risks related to necrotic bone resection or a …

Expanding Image Datasets For Deep Learning By Evaluating Independence Through Coefficient Correlation And Mean-Squared Error, Ayman Yousef

Biomedical Engineering Undergraduate Honors Theses

With deep learning being leveraged more regularly in the field of image classification, particularly in medical imaging, network optimizations have become a field in and of itself. With open source, comprehensive medical image datasets few and far, computational dataset expansion has become a useful tool for researchers without the ability to further manually collect data. However, with the rich amount of data that imaging modalities like multi-photon microscopy collect at a time, there is potential to expand datasets through proper utilization of this data that often time goes unused. Previous deep learning studies have shown that improper expansion can conflate …

Guide Rnas Preparation For In-Vitro Crispr-Cas9 Complex Delivery Targeting Genes That Affect Wound Healing., Prashant Khatiwada

Biomedical Engineering Undergraduate Honors Theses

CRISPR-Cas9 technology has widely been used as a viable genome engineering platform to make site-specific insertion, deletion, and breaks. The nuclease dead version of Cas9 or dCas9 can be used for the activation and repression of target gene sites using specific activation or repression domains. In this study, CRISPR guide RNAs were designed for a CRISPR inhibition approach to repress the transcriptional activity of the target genes. An expression plasmid vector composed of a U6 promoter sequence, BbsI restriction sites, and a chimeric gRNA sequence was digested, and the phosphorylated forward and reverse gRNAs were ligated with the plasmid vector. …

Using Deep Learning To Analyze Materials In Medical Images, Carson Molder

Computer Science and Computer Engineering Undergraduate Honors Theses

Modern deep learning architectures have become increasingly popular in medicine, especially for analyzing medical images. In some medical applications, deep learning image analysis models have been more accurate at predicting medical conditions than experts. Deep learning has also been effective for material analysis on photographs. We aim to leverage deep learning to perform material analysis on medical images. Because material datasets for medicine are scarce, we first introduce a texture dataset generation algorithm that automatically samples desired textures from annotated or unannotated medical images. Second, we use a novel Siamese neural network called D-CNN to predict patch similarity and build …

Glial Endothelial Brain Cell Co-Cultures For Testing Signaling Response And Delivery Of Novel Materials Across Blood Brain Barrier, Neela Prajapati

Doctoral Dissertations

The brain accounts for 20% of overall energy metabolism in the body though it just comprises 2% of the total body mass but has a limited capacity of storing energy unlike other critical organs in the body such as the heart and liver. This energy along with oxygen and nutrients is supplied by cerebral blood flow (CBF), any interruption of which can cease the brain function within seconds with a potential irreversible neuronal injury, within minutes. Vascular cells along with astrocytes and neurons are a part of a recently developed concept known as the Neurovascular Unit responsible for Neurovascular coupling …

Quantifying Blood Flow Patterns In The Pediatric Heart Using Blood Speckle Imaging, Harrison Dean

Biomedical Engineering Undergraduate Honors Theses

Congenital Heart Disease (CHD) is the most common type of congenital disease worldwide. Echocardiography using Doppler ultrasound is typically used to diagnose and monitor CHD; however, it is angle-dependent in nature and as a result is limited in its ability to accurately evaluate ventricular function. Blood Speckle Imaging (BSI) is a novel, angle-independent imaging modality that provides detailed blood flow information and visualization within a given area using speckle-tracking. In this study, velocity-field information obtained from BSI was used to calculate flow parameters such as kinetic energy (KE) and circulation using a custom created MATLAB program. BSI was performed on …

Biomechanical Studies Of Developing Zebrafish Heart In-Vivo, Nabid Salehin

Bioengineering Dissertations - Archive

The heart is an electrically controlled mechanical pump that provides the cardiac output required by the body to function properly and flexibly adapts to changing demand and working conditions. In vertebrate embryos, the heart is the first organ that starts functioning and the function is initiated well before structural organogenesis is complete, with its early mechanical function affecting its own development. During development, the heart transforms from a valveless linear peristaltic tube into a multi-chambered pulsatile pump with blood flow regulating valves while continuing to serve the metabolic needs of the embryo. The zebrafish has emerged as a popular model …

Non-Invasive Profiling Of Molecular Markers In Brain Gliomas Using Deep Learning And Magnetic Resonance Images, Chandan Ganesh Bangalore Yogananda

Bioengineering Dissertations - Archive

Gliomas account for the most common malignant primary brain tumors in both pediatric and adult populations. They arise from glial cells and are divided into low grade and high-grade gliomas with significant differences in patient survival. Patients with aggressive high-grade gliomas have life expectancies of less than 2 years. Glioblastoma (GBM) are aggressive brain tumors classified by the world health organization (WHO) as stage IV brain cancer. The overall survival for GBM patients is poor and is in the range of 12 to 15 months. These tumors are typically treated by surgery, followed by radiotherapy and chemotherapy. Gliomas often consist …

Metabolic And Electrophysiological Effects Of Transcranial Photobiomodulation (Pbm) And Multi-Wavelength Pbm, Tyrell Byrom Pruitt

Bioengineering Dissertations - Archive

Photobiomodulation (PBM) with near infrared light may become a non-invasive, effective clinical tool after it is understood well for its mechanism of action. In my dissertation research, I have addressed three research questions as three aims to achieve. Aim 1 was to investigate and demonstrate the reproducibility of the effects of transcranial PBM (tPBM) with 1064-nm laser delivered on the right forehead of separate groups of healthy humans measured using different experiment setups in separate sites and years. In Chapter 2, I reported sham-controlled, tPBM-induced concentration increases in oxygenated hemoglobin (∆[HbO]) and oxidized cytochrome c oxidase (∆[oxi-CCO]) in both young …

An In Vitro Model To Study The Role Of Iol: Lens Capsule Interactions In Posterior Capsule Opacification, Arjun Jaitli

Bioengineering Dissertations - Archive

Posterior capsule opacification (PCO) is the most common complication associated with intraocular lens (IOL) implantation. Unfortunately, current in vitro models cannot be used to assess the potential of PCO due to their failure to simulate posterior curvature of the lens capsule (LC), contradicting observations, different testing conditions and inherent challenges associated with use of human capsular bag models, cells and other tissue substrates. To overcome such a challenge, a new system to study IOL: LC interaction and potentially predict PCO was developed in this effort. It is believed that the interactions between an IOL and the lens capsule (LC) may …

Biomechanical Characterization Of Video-Recorded Short-Distance Falls Involving Children Equipped With A Biometric Device In A Childcare Setting: A Pilot Study., Danielle K. Cory

Electronic Theses and Dissertations

Background: A fall is the most common falsely reported injury scenario when a young child presents for medical care and the caregiver is concealing abuse. There is a lack of reliably witnessed falls with known outcomes to aid in the distinction between accidental and abusive injuries.

Objectives: The objectives of this study were to characterize video-recorded short distance falls involving young children in a childcare setting, to identify body regions most commonly impacted in these short distance falls, to characterize the head biomechanics of these falls, and describe fall characteristics. Additionally, physics-based models were used to predict fall biomechanics in …

Automated Conversion Of Multicellds Digital Cell Lines And Isa-Tab Filesets., Connor Joseph Burns

Electronic Theses and Dissertations

Biological simulation tools are a valuable asset to bridge the gap between biological experimentation and biological theory. As systems thinking has become more regularly applied to biological materials and processes, these materials and processes have been characterized in multi-disciplinary, computational manners. This characterization has yielded an ability to create more realistic simulation tools that can provide in silico experiments for a wider range of scenarios. One prominent simulation tool is PhysiCell, an open-source physics-based multicellular simulation program which utilizes input Digital Cell Lines or Digital Snapshots from the MultiCellular Data Standard (MCDS) project.

This project aims to allow data exchange …

Development And Applications Of In-Vitro And In-Silico Models Of The Cardiovascular System To Study The Effects Of Mechanical Circulatory Support., Moustafa Meki

Electronic Theses and Dissertations

Cardiovascular diseases (CVDs) are the leading cause of mortality globally. With ongoing interest in CVDs treatment, preclinical models for drug/therapeutic development that allow for fast iterative research are needed. Owing to the inherent complexity of the cardiovascular system, current in-vitro models of the cardiovascular system fail to replicate many of the physiological aspects of the cardiovascular system. In this dissertation, the main concern is with heart failure (HF). In advanced HF, patients may receive Left Ventricular Assist Devices (LVADs) as a bridge to transplant or destination therapy. However, LVADs have many limitations, including inability to adapt to varying tissue demand …

Optimal Analytical Methods For High Accuracy Cardiac Disease Classification And Treatment Based On Ecg Data, Jianwei Zheng

Computational and Data Sciences (PhD) Dissertations

This work constitutes six projects. In the first project, a newly inaugurated research database for 12-lead electrocardiogram signals was created under the auspices of Chapman University and Shaoxing People's Hospital (Shaoxing Hospital Zhejiang University School of Medicine). This database aims to enable the scientific community in conducting new studies on arrhythmia and other cardiovascular conditions. In the second project, we created a new 12-lead ECG database under the auspices of Chapman University and Ningbo First Hospital of Zhejiang University that aims to provide high quality data enabling detection of the distinctions between idiopathic ventricular arrhythmia from right ventricular outflow tract …

Quantifying Mucosal Hemodynamics In A Murine Model Of Ulcerative Colitis With Diffuse Reflectance Spectroscopy, Elizabeth A. Bullard, Ariel I. Mundo, Shelby N. Bess, Kathryn P. Miller

Biomedical Engineering Undergraduate Honors Theses

Ulcerative colitis (UC) is a gastrointestinal, autoimmune disease that causes ulceration and inflammation of the colon with an incidence 10 out of every 100,000 people in North America and Western Europe. Though the exact etiology is uncertain, a number of studies have shown that inflammatory cells along with environmental factors, genetics, and lifestyle habits can contribute to the sustained inflammatory response. In order to determine the cellular mechanism behind relapse and remission of UC, researchers have frequently employed immunohistochemistry, western blotting and gene sequencing, but these destructive analysis methods require the removal of a sample, necessarily limiting these methods to …

Evaluating Cellular Response Of Different Valve Interstitial Cell (Vic) Phenotypes To Angiotensin I, Smit Patel

Biomedical Engineering Undergraduate Honors Theses

Calcific Aortic Valve Disease (CAVD), one of the leading causes of death in the United States, is characterized by diminished functioning and limited movement of the aortic valve (AV) due to increased thickening, disorganized extracellular matrix elastin fibers, increased collagen content, and abnormal deposition and formation of calcium nodules on the AV [1, 2]. There are two types of CAVD: i) Aortic valve sclerosis (AVS), in which patients suffer from tissue hardening, fibrosis, and early calcification, and ii) calcific aortic stenosis (CAS), representative by excessive calcification on the AV and reduced AV opening, are the two main forms of CAVD …

Involvement Of The Ino80 Chromatin Remodeling Complex In Cell Division And Genomic Stability, Ethan Chen

Biomedical Engineering Undergraduate Honors Theses

Cell division is a vital biological process for growth and development in both single and multi-cellular organisms—whereby the cell must duplicate its organelles and genome in entirety and appropriately distribute the copied contents to the daughter cells. Cells undergo a cycle of two distinct phases: interphase and mitosis. During interphase, the cell replicates its genomic DNA (in the form of chromosomes) located within the nucleus. DNA replication is carried out in a euchromatin state, where the chromosome structure is loose and easily accessible by DNA polymerase and other replication enzymes. Upon the completion of replication, chromatin is condensed into highly …

Quantification Of Superoxide Production In Cells Treated With L-Buthionine Sulfoximine, Rebekah Townsley

Biomedical Engineering Undergraduate Honors Theses

Hydroxyl radicals, superoxides, and hydrogen peroxides are common reactive oxygen species (ROS) that are produced by the mitochondria during cellular respiration [1]. Signal transduction pathways in the mitochondria are used to maintain the balance of ROS. However, when these mechanisms fail to regulate ROS properly, it causes oxidative damage and can lead to the development of various diseases such as cancer, respiratory, neurodegenerative, and cardiovascular diseases. L-buthionine sulfoximine (BSO) has been used previously to induce oxidative stress by inhibiting the γ-GCS enzyme used to synthesize glutathione, an antioxidant used to convert ROS to water [3]. BSO reduces glutathione production, thus …

New Force Transducer For Mitral Valve Chordae Tendinea, Joseph Berryman

Biomedical Engineering Undergraduate Honors Theses

In order to inform the future of mitral valve repair and replacement, more investigation into the mechanics of the sub-valvular structure is needed. Understanding the roles of each chord during valve closure requires a sensor capable of detecting these small forces with enough sensitivity to determine the characteristics of each of the chordal types. The focus of the cantilever force transducer is to maximize this sensitivity while also minimizing the invasiveness of the sensor on the overall function of the chord. The design utilizes flexible yet strong 3D printed resin and cantilever arms to improve the strain exerted on a …

Use Of 3d-Printed Surgical Spoons Compared To Other Cystotomy Methods In Dogs, Davina D'Angelo

Animal Science Undergraduate Honors Theses

Bladder stones, also known as uroliths, are not an uncommon condition in domestic dogs. To remove these uroliths, which occur in various sizes, shapes, and compositions, veterinarians will perform a surgical procedure called a cystotomy. A cystotomy consists of creating a small incision into the lumen of the urinary bladder and the utilization of various methods to extract the uroliths. For general veterinary practitioners, the laparoscopic-assisted technique is unavailable. As a result, the methods available for urolith extraction are often limited to flushing the stones out by inserting a urinary catheter through the urinary tract and the use of off-label …

Development Of An Intraperitoneal Catheter Placement Device For Use On The Battlefield, Riley Reynolds

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

The objective of this project was to simplify peritoneal cavity access so an Airforce field medic can safely infuse oxygen microbubbles (OMBs) into the intraperitoneal space for the emergency treatment of hypoxia due to lung damage. To solve this problem, we created an intraperitoneal catheter placement device for use on the battlefield. The three common methods and some of the most common devices for peritoneal cavity access were reviewed. Injury frequencies for each of the three methods were analyzed. The results showed that each of the access techniques gives a similar rate of iatrogenic injury.

The battlefield conditions where the …

Photomodulatory Effects On Insulin Secreting Beta Cells, Sheccid Alejandra Loya

Bioengineering Theses - Archive

Diabetes mellitus is a chronic metabolic disease characterized by increased blood glucose levels and affects more than 8% of people worldwide (Rutter et. al, 2015). Typically, diabetes is divided into two large subcategories: type 1 diabetes (T1D) and type 2 diabetes (T2D). T1D is an autoimmune disorder caused by the attack of insulin secreting cells by t-cell mediated inflammatory response (Khrraoubi & Darwish, 2015). Currently, islet transplants offer a clinical treatment for restoration of glucose control. However, the current procedure may not be optimal as many transplanted islets do not survive because of the stresses induced during the process (Miki …

Statistical Machine Learning For Breast Cancer Detection With Terahertz Imaging, Tanny Andrea Chavez Esparza

Graduate Theses and Dissertations

Breast conserving surgery (BCS) is a common breast cancer treatment option, in which the cancerous tissue is excised while leaving most of the healthy breast tissue intact. The lack of in-situ margin evaluation unfortunately results in a re-excision rate of 20-30% for this type of procedure. This study aims to design statistical and machine learning segmentation algorithms for the detection of breast cancer in BCS by using terahertz (THz) imaging. Given the material characterization properties of the non-ionizing radiation in the THz range, we intend to employ the responses from the THz system to identify healthy and cancerous breast tissue …

Evaluating The Effects Of Wood Source On The Physicochemical Properties Of Crosslinked Cellulose Nanocrystals, Helena Tchoungang Nkeumen

Graduate Theses and Dissertations

Cellulose is an abundant and naturally occurring biopolymer that has been used by humans for food, shelter, and clothing for about two centuries now. Highly crystalline nanoparticles derived from cellulose, called cellulose nanocrystals (CNCs), show great potential to meet the rising need for sustainable and nontoxic materials for biomedical applications. However, multiple biomedical applications of CNCs, such as those involving their use in tissue engineering scaffolds, require CNC-based structures to be stable in aqueous environments, a property that native CNCs do not possess due to their inherent hydrophilicity. Chemical crosslinking of CNCs addresses this issue by providing aqueous stability to …

Quantifying The Effect Of Intrinsic Aging On Skin Microstructure And Mechanical Function Using Multiphoton Microscopy, Alan Edward Woessner

Graduate Theses and Dissertations

Over the next couple of decades, the number of elderly individuals is expected to double, bringing increased healthcare spending due to seemingly minor injuries to skin. In skin, the 3D dermal collagen fiber network, which is the primary load-bearing structure, undergoes changes in organization and composition due to intrinsic aging. However, the relationships between altered microstructure and mechanical function is not well understood. Quantitative imaging techniques have been used in the past to link skin structure to mechanical function, but previous analysis has been limited to 2D assessments. Multiphoton microscopy (MPM) is a non-destructive imaging technique with intrinsic depth-sectioning capabilities, …

Simulation Of Fracture Strength Improvements Of A Human Proximal Femur Using Finite Element Analysis., Waleed Ebraheem Alim

Electronic Theses and Dissertations

The most common hip fracture in the elderly occurs as a result of a fall to the side with impact over the greater trochanter resulting in a fracture of the proximal femur. The fracture usually involves the femoral neck or the intertrochanteric region. It has recently been determined that the fracture crack of a hip fracture typically initiates on the superior-lateral cortex of the femoral neck and then propagates across the femoral neck, resulting in a complete fracture. The strength of the superior-lateral cortex of the femoral neck is likely determined by the combined properties of the generally thin cortex …

Monitoring Fgf1-Treated Skin Wounds With Label-Free Multiphoton Microscopy, Gianna Busch

Biomedical Engineering Undergraduate Honors Theses

Chronic skin wounds pose a significant threat to public health, affecting as many as 5.5 million people in the United States every year and costing the healthcare system $10 billion annually^1,2. These wounds are associated with prolonged inflammation, poor vascularization, increased infection risk, and high mortality rates^3,4. There is significant interest in developing and testing a variety of biologics to promote wound healing. However, quantitative evaluations of healing are typically limited to measurements of wound size, and there is a critical need to develop quantitative biomarkers sensitive to different aspects of the healing process. Label-free multiphoton …