Biomedical Engineering and Bioengineering Commons^™

Development Of Highly Sensitive And Selective Breathing Sensors Using Molecular Imprinted Filtering For Diabetic And Alcoholic Patients, Md. Saleh Akram Bhuiyan

Electronic Theses and Dissertations

Wellness sensor technology is an emerging diagnostic test research field, which mostly deal with the point of care of the patients in the recent days. Due to the lack of awareness from the patients, most diseases cannot be detected in due time. This led to worse conditions, such as diabetic and alcoholic syndrome. Therefore, many research groups have been working to develop portable sensor devices that can track serious diseases. These include diabetic and alcoholic biomarkers in breathing. These devices have very high selectivity and reliability. However, the major limitation of biomarkers is that it deals with the bio-molecular based …

Electrotransfer Of Plasmid Dna Radiosensitizes B16f10 Tumors Through Activation Of Immune Response, Monika Savarin, Urska Kamensek, Maja Cemazar, Richard Heller, Gregor Sersa

Bioelectrics Publications

Background. Tumor irradiation combined with adjuvant treatments, either vascular targeted or immunomodulatory, is under intense investigation. Gene electrotransfer of therapeutic genes is one of these approaches. The aim of this study was to determine, whether gene electrotransfer of plasmid encoding shRNA for silencing endoglin, with vascular targeted effectiveness, can radiosensitize melanoma B16F10 tumors.

Materials and methods. The murine melanoma Bl6F10 tumors, growing on the back of C57BI/6 mice, were treated by triple gene electrotransfer and irradiation. The antitumor effect was evaluated by determination of tumor growth delay and proportion of tumor free mice. Furthermore, histological analysis of tumors (necrosis, apoptosis, …

Transient Alt Activation Protects Human Primary Cells From Chromosome Instability Induced By Low Chronic Oxidative Stress, Elisa Coluzzi, Rossella Buonsante, Stefano Leone, Anthony J. Asmar, Kelley L. Miller, Daniela Cimini, Antonella Sgura

Bioelectrics Publications

Cells are often subjected to the effect of reactive oxygen species (ROS) as a result of both intracellular metabolism and exposure to exogenous factors. ROS-dependent oxidative stress can induce 8-oxodG within the GGG triplet found in the G-rich human telomeric sequence (TTAGGG), making telomeres highly susceptible to ROS-induced oxidative damage. Telomeres are nucleoprotein complexes that protect the ends of linear chromosomes and their dysfunction is believed to affect a wide range of cellular and/or organismal processes. Acute oxidative stress was shown to affect telomere integrity, but how prolonged low level oxidative stress, which may be more physiologically relevant, affects telomeres …

Electrosensitization Increases Antitumor Effectiveness Of Nanosecond Pulsed Electric Fields In Vivo, Claudia Muratori, Andrei G. Pakhomov, Loree Heller, Maura Casciola, Elena Gianulis, Sergey Grigoryev, Shu Xiao, Olga N. Pakhomova

Bioelectrics Publications

Nanosecond pulsed electric fields are emerging as a new modality for tissue and tumor ablation. We previously reported that cells exposed to pulsed electric fields develop hypersensitivity to subsequent pulsed electric field applications. This phenomenon, named electrosensitization, is evoked by splitting the pulsed electric field treatment in fractions (split-dose treatments) and causes in vitro a 2- to 3-fold increase in cytotoxicity. The aim of this study was to show the benefit of split-dose treatments for in vivo tumor ablation by nanosecond pulsed electric field. KLN 205 squamous carcinoma cells were embedded in an agarose gel or grown subcutaneously as tumors …

Nanosecond Pulsed Electric Field Induced Changes In Cell Surface Charge Density, Diganta Dutta, Xavier-Lewis Palmer, Anthony Asmar, Michael Stacey, Shizhi Qian

Bioelectrics Publications

This study reports that the surface charge density changes in Jurkat cells with the application of single 60 nanosecond pulse electric fields, using atomic force microscopy. Using an atomic force microscope tip and Jurkat cells on silica in a 0.01 M KCl ionic concentration, we were able to measure the interfacial forces, while also predicting surface charge densities of both Jurkat cell and silica surfaces. The most important finding is that the pulsing conditions varyingly reduced the cells' surface charge density. This offers a novel way in which to examine cellular effects of pulsed electric fields that may lead to …

Modulating The Innate Immune Response To Electrospun Scaffolds And Polymer Degradative Byproducts, Daniel Abebayehu

Theses and Dissertations

Implanted biomaterials often induce inflammation that frequently leads to the foreign body response, fibrosis, and the failure of the implant. Thus, it is important to evaluate how cells interact with materials to promote a more regenerative response. It is critical to determine how to modulate the response of tissue resident innate immune cells, as they are among the first cells to interact with implanted materials. Among tissue resident innate immune cells are mast cells, which are inflammatory sentinels that degranulate and orchestrate the fate of other cell populations, such as monocytes/macrophages and lymphocytes. Mast cells have also been reported to …

Freeze-Drying As A Novel Biofabrication Method For Achieving A Controlled Microarchitecture Within Large, Complex Natural Biomaterial Scaffolds, Claire Brougham, Tanya J. Levingstone, Nian Shen, Gerard M. Cooney, Thomas C. Flanagan, Stefan Jockenhoevel, Fergal J. O’Brien

Articles

The biofabrication of large scaffolds from natural biomaterials into complex 3D shapes with controllable microarchitecture remains a major challenge. Freeze-drying (or lyophilization) is a technique used to create bioactive scaffolds with a porous architecture and is typically only used to generate scaffolds in planar 3D geometries. Here we report the development of a new biofabrication process to form a collagen-based scaffold into a large, complex geometry which has a large height to width ratio, and a controlled porous microarchitecture. This biofabrication process was validated through the successful development of a heart valve shaped scaffold, fabricated from a collagen-glycosaminoglycan co-polymer. Notably, …

Design Of A Modular Endothelialized Platform For Vascularized Bone Regeneration, Kevin Barrett Miles

Wayne State University Dissertations

The gold standard for bone regeneration requires harvesting a piece of healthy bone from the patient through a painful procedure, but this piece of autologous bone graft contains the bone and endothelial cells required to rapidly regenerate bone in a defect. We have developed a modular bone regeneration platform, composed of mesenchymal stem cells (MSCs) and hydroxyapatite (HAP) microgranules encapsulated in microcapsules, to replace autologous graft harvesting. The microcapsules are composed of a polyelectrolyte membrane formed by the ionic-complex reaction between chondroitin 4-sulfate (C4S) and chitosan. The specific aims of this thesis were to 1) examine the ability of C4S/HAP/chitosan …

Profiling Resistance To P450-Activated Food Carcinogens Using Toxicogenomic Approaches In Budding Yeast, Nicholas Stjohn

Legacy Theses & Dissertations (2009 - 2024)

The human response to environmental carcinogens, some of which require metabolic activation, is highly variable. Factors such as environment, lifestyle, and genetics all influence the rates of exposure to and ultimate bioactivation of these compounds. Genetic factors include mutations to cell-cycle regulation, cell proliferation, and DNA repair genes; however, epidemiological studies may lack significance due to inadequate patient numbers. We used budding yeast as a model organism to determine genetic susceptibility to food-associated carcinogens, including aflatoxin (AFB1) and heterocyclic aromatic amines (HAAs). Budding yeast does not contain P450s that activate these compounds, so expression vectors were induced that contain human …

Detecting And Analyzing Trna Modification Systems And Homologs Using In Silico And Colorectal Cancer Models, Khadijah Onanuga

Legacy Theses & Dissertations (2009 - 2024)

tRNA modifications can be considered epitranscriptomic signaling components that regulate translation and play integral roles in stress response pathways. As such, tRNA modification enzymes have roles in cancer etiology and potential utility as biomarkers of pathological states. For my thesis project I have used computational and wet bench approaches to study tRNA modification systems. Chapter two of my thesis deals with tRNA modification detection, as current methods are costly, time consuming, and require RNA fragmentation. I present a single-molecule-based approach for RNA modification detection, which involves in slico studies using a 5-layered graphene nanopore. Our simulations using a 1.5 nm …

การพัฒนาเครื่องพลาสมาเย็นแบบเจ็ตที่ความดันบรรยากาศสำหรับการทำให้เลือดแข็งตัว, ณัฐนพิญช์ จรูญศักดิ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้เป็นการพัฒนาเครื่องพลาสมาเย็นแบบเจ็ตที่ความดันบรรยากาศสำหรับการทำให้เลือดแข็งตัวที่ประกอบด้วย 2 ส่วนหลักคือ แหล่งจ่ายไฟฟ้าแรงดันสูงความถี่สูงชนิดกระแสสลับ แบบฟลายแบค (Fly back) ที่ควบคุมการทำงานด้วยไมโครคอนโทรลเลอร์และพลาสมาโปรบด้วยวัสดุอุปกรณ์ที่หาได้ในประเทศ โดยออกแบบให้สามารถปรับตั้งค่าความถี่และดิวตี้ไซเคิลผ่านระบบไมโครคอนโทรลเลอร์ได้ที่ความถี่ 30 35 และ 40 kHz และเปอร์เซ็นต์ดิวตี้ไซเคิล 30 40 50 และ 70 % ตามลำดับ ส่วนการปรับตั้งค่าของไฟฟ้าแรงดันสูงเป็นการปรับด้วยมือได้ตั้งแต่ 0.1 ถึง 15 kVrms จากผลการทดลองพบว่า แหล่งจ่ายไฟฟ้าแรงดันสูงความถี่สูงชนิดกระแสสลับที่พัฒนาขึ้นมีประสิทธิภาพการทำงานเท่ากับ 74.28 % การศึกษาผลกระทบของตัวแปรต่างๆต่อความยาวและอุณหภูมิของพลาสมาเจ็ต พบว่าค่าไฟฟ้าแรงดันสูง ความถี่ เปอร์เซ็นต์ดิวตี้ไซเคิล และอัตราการไหลของก๊าซอาร์กอน เป็นตัวแปรสำคัญที่ส่งผลต่อความสม่ำเสมอของเปลวพลาสมา ผลการวิเคราะห์คุณสมบัติของพลาสมาด้วยเครื่อง Optical Emission Spectroscopy (OES) พบว่า มีอุณหภูมิของอิเล็กตรอนที่ความถี่ต่างๆและที่อัตราการไหลต่างๆที่มีค่าเท่ากับ 0.43 eV และความหนาแน่นของอิเล็กตรอนของพลาสมาอยู่ในช่วง 5.46x109 – 1.74x1012 cm-3 ซึ่งสามารถระบุได้ว่าพลาสมาแบบเจ็ตที่พัฒนาขึ้นเป็นพลาสมาเย็น จากผลทดสอบการแข็งตัวของเลือดด้วยเครื่องพลาสมาเย็นแบบเจ็ตที่พัฒนาขึ้น พบว่า ที่ระยะห่างระหว่างปลายโปรบกับกระจกสไลด์ 1 เซนติเมตร พลาสมาเย็นแบบเจ็ตที่พัฒนาขึ้นสามารถทำให้เลือดที่ผสมสารต้านการแข็งตัวของเลือด EDTA ปริมาณ 2.5 µL. ให้แข็งตัวภายในเวลาประมาณ 20 วินาที ได้เร็วกว่าเลือดผสมสาร EDTA ที่ไม่ผ่านการฉายด้วยพลาสมาและเลือดผสมสาร EDTA ที่ผ่านการเป่าด้วยก๊าซอาร์กอนที่อัตราการไหลของก๊าซอาร์กอน 5 L/min

Mri Methods For Imaging The Feto-Placental Vasculature And Blood, Uday Krishnamurthy

Wayne State University Dissertations

Fetal magnetic resonance imaging (MRI) in recent times has become a well-established adjunct to ultrasound (US) in routine clinical prenatal care and diagnostics. The majority of fetal MRI is restricted to T2-weighted scans, where the diagnosis is based on the appearance of normal and abnormal tissue. Although there have been many advancements in MRI and a plethora of sequences, that probe different anatomical and different physiological process, the adaptation of these in fetal imaging has been rather slow. Many of these can extract quantitative parameters that can throw light on the underlying tissue’s normal/patho-physiology. But the use of such quantitative …

Biomaterials Approaches For Utilizing The Regenerative Potential Of The Peripheral Nerve Injury Microenvironment, Melissa Renee Wrobel

Wayne State University Dissertations

Clinically available treatments are insufficient to achieve full functional recovery in large (>3cm) peripheral nerve injuries (PNI). The objectives in this thesis were 1) to study often overlooked elements of intrinsic PNI repair including release of inhibitory CSPGs and post-injury responses of inflammatory macrophages and dedifferentiated Schwann cells; 2) to create biomaterial scaf-folds featuring topographical and adhesive cues to enhance neurite outgrowth; and 3) to test the ability of those cues to direct macrophages and Schwann cells towards a pro-regenerative phe-notype. It is hypothesized that recapitulating the positive and negative cues of the PNI microenvi-ronment can better improve regeneration. …

Utility Of Ultrasound/Photoacoustic Imaging For Accurate Catheter Tracking And Temperature Monitoring During Endovenous Laser Ablation, Ayushi Jharia, Keerthana Palani, Yan Yan

Research Opportunities for Engineering Undergraduates (ROEU) Program 2016-17

Laser ablation is a treatment method that uses light energy through a catheter inserted into a vein to induce localized heat to close the diseased blood vessels. Ultrasound (US) imaging has been used for catheter visualization and tracking. US has limitations for tracking the accurate location of the fiber tip inside small perforating veins such as angular dependency and comet tail artifacts. We propose a robust and accurate method for fiber tip tracking using combined US and Photoacoustic (PA) imaging to overcome the existing limitations.

A Structural And Functional Analysis Of Human Brain Mri With Attention Deficit Hyperactivity Disorder, Arjun A. Watane

Honors Undergraduate Theses

Attention Deficit Hyperactivity Disorder (ADHD) affects 5-10% of children worldwide. Its effects are mainly behavioral, manifesting in symptoms such as inattention, hyperactivity, and impulsivity. If not monitored and treated, ADHD may adversely affect a child's health, education, and social life. Furthermore, the neurological disorder is currently diagnosed through interviews and opinions of teachers, parents, and physicians. Because this is a subjective method of identifying ADHD, it is easily prone to error and misdiagnosis. Therefore, there is a clear need to develop an objective diagnostic method for ADHD.

The focus of this study is to explore the use of machine language …

Quantifying The Effects Of Hydrostatic Pressure On Fibroblast Growth Factor-2 Binding By The Human Endothelium, Taylor R. Mckenty

Theses and Dissertations--Biomedical Engineering

Fluid pressures regulate endothelial cell (EC) tubulogenic activity involving fibroblast growth factor 2 (FGF-2) and its receptor, FGF receptor 2 (FGFR2). Our lab has recently shown that sustained 20 mmHg hydrostatic pressure (HP) upregulates EC sprout formation in a FGF2-dependent fashion. This upregulation of sprout formation may be due to enhanced FGF-2 / FGFR2 interactions in the presence of 20 mmHg HP. We hypothesize that exposure of ECs to 20 mmHg sustained HP enhances FGF-2 binding kinetics. We used a custom hydrostatic pressure system, immunofluorescence, and FACS to quantify FGF-2 binding by ECs in the absence or presence of a …

Age-Related Differences In The Lumbopelvic Kinematics During The Trunk Motions In The Anatomical Planes, Milad Vazirian

Theses and Dissertations--Biomedical Engineering

Management and control of the low back pain as an important health problem in the industrial societies necessitates to investigate how the risk of this disease is affected by aging. Since the abnormalities of the lumbopelvic kinematics are related to the existence or risk of low back injuries, the objective of this dissertation was set to find the age-related differences in lumbopelvic kinematics when performing basic trunk motions reaching to range of motion in different anatomical planes.

A cross-sectional study was designed where sixty asymptomatic individuals between 20–70 years old with no confounding health condition, no current or previous highly …

Synthesis And Characterization Of Poly(Simvastatin) - Incorporated Copolymers And Blends For Bone Regeneration, Theodora Asafo-Adjei

Theses and Dissertations--Biomedical Engineering

Common biodegradable polyesters such as poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA) and poly(ε-caprolactone) (PCL) are used as drug delivery vehicles for tissue regenerative applications. However, they are typically bioinert, with drug loading limitations. Polymerizing the active agent or precursor into its respective biodegradable polymer would control drug loading via molar ratios of drug to initiator used for synthesis. Simvastatin was chosen due to its favorable anti-inflammatory, angiogenic, and osteogenic properties. In addition, its lactone ring lends itself to ring-opening polymerization and, consequently, the synthesis of poly(simvastatin) with controlled simvastatin release.

Simvastatin was first polymerized with a 5kDa methyl-terminated poly(ethylene glycol) …

Validation, Optimization, And Image Processing Of Spiral Cine Dense Magnetic Resonance Imaging For The Quantification Of Left And Right Ventricular Mechanics, Gregory J. Wehner

Theses and Dissertations--Biomedical Engineering

Recent evidence suggests that cardiac mechanics (e.g. cardiac strains) are better measures of heart function compared to common clinical metrics like ejection fraction. However, commonly-used parameters of cardiac mechanics remain limited to just a few measurements averaged over the whole left ventricle. We hypothesized that recent advances in cardiac magnetic resonance imaging (MRI) could be extended to provide measures of cardiac mechanics throughout the left and right ventricles (LV and RV, respectively).

Displacement Encoding with Stimulated Echoes (DENSE) is a cardiac MRI technique that has been validated for measuring LV mechanics at a magnetic field strength of 1.5 T but …

Fractionation And Characterization Of Lignin Streams From Genetically Engineered Switchgrass, Enshi Liu

Theses and Dissertations--Biosystems and Agricultural Engineering

Development of biomass feedstocks with desirable traits for cost-effective conversion is one of the main focus areas in biofuels research. As suggested by techno-economic analyses, the success of a lignocellulose-based biorefinery largely relies on the utilization of lignin to generate value-added products, i.e. fuels and chemicals. The fate of lignin and its structural/compositional changes during pretreatment have received increasing attention; however, the effect of genetic modification on the fractionation, depolymerization and catalytic upgrading of lignin from genetically engineered plants is not well understood. This study aims to fractionate and characterize the lignin streams from a wild-type and two genetically engineered …