Biomedical Engineering and Bioengineering Commons^™

Pulsed Electric Field Ablation: Mechanisms Of Differential Cell Sensitivity And Methods To Mitigate Neuromuscular Excitation, Emily Gudvangen

Biomedical Engineering Theses & Dissertations

Ablation therapies aim to destroy tumors while maintaining minimal damage to surrounding healthy tissue. Pulsed electric field (PEF) ablation targets the cell membrane during the destruction of tissues, which consequently spares extracellular structures such as ducts and blood vessels, leaving the framework for tissue regeneration. However, the utility of PEF is limited by neuromuscular excitation, causing pain and involuntary muscle contraction. To identify PEF protocols that efficiently ablate tissue while minimizing neuromuscular stimulation, various PEF protocols differing in pulse duration, shape, and repetition rate were tested. The ratio of cell death and nerve excitation thresholds, which determines the range of …

Cheiloscopy Examination And Classification Of Lip Prints With And Without Parafunctional Oral Habits: A Cross-Sectional Observation Study, Emily Smith Regan

Dental Hygiene Theses & Dissertations

Problem: Lip prints are unique and have potential for use as a human identifier. The purpose of this study was to observe possible cheiloscopy differences of individuals with and without parafunctional oral habits. Additionally, inter-rater reliability (IRR) of lip print examiners was observed. Methods: This IRB approved blinded cross-sectional observational study collected lip prints from sixty-six individuals using lipstick and adhesive tape to transfer lip prints to white bond paper for viewing purposes. Each set of included lip prints was divided into quadrants and dichotomized as those with or without an oral parafunctional habit. Each quadrant sample was manually analyzed …

Investigation Of Nanosecond Pulsed Electric Fields (Nspef) Induced Anti-Cancer Mechanism And Enhanced B16f10 Melanoma Cancer Treatment, Kamal Asadipour

Biomedical Engineering Theses & Dissertations

The use of nanosecond pulsed electric fields (nsPEF) has emerged as a promising area of research with vast implications across various scientific disciplines. The ability to generate ultra-short, high-voltage electric pulses has paved the way for numerous applications, ranging from fundamental investigations of biological phenomena to the development of innovative medical therapies. The aim of this thesis is to highlight the importance of nsPEF in two critical areas: 1) Understanding the impact of subtle postpulse waveforms through a comprehensive analysis of two common pulse generators and 2) using this knowledge to advance melanoma treatment by enhancing the therapeutic effect of …

Engineering Of Functionalized Carbon Nano-Onions Embedded Bsa Nanocomposite Fibers For Stimuli-Responsive Drug Release, Ramiro Manuel Velasco Delgadillo, Narsimha Mamidi

Research Symposium

Background: Advanced drug delivery systems (DDSs) have received enormous attention in biomedical applications due to their pharmacodynamic and pharmacokinetic drug properties. For the present study, poly 4-hydroxyphenyl methacrylate (PHPMA)/CNOs (f-CNOs) inserted bovine serum albumin (BSA) nanofibers were prepared for stimuli-responsive release of Doxorubicin (DOX). Temperature and pH would be altered to study the release of DOX in acidic microenvironments.

Methods: PHPMA were coupled with COOH-CNOs via ester coupling via the sonochemical method to produce PHPMA-CNOs (f-CNOs). Then, f-CNOs/DOX embedded BSA nanofibers were prepared at room temperature using Forcespinning. UV spectra of DOX-loaded nanofibers were studied to investigate the …

Engineered Exosomes For The Multimodal Imaging Directed Photo-Immunotherapy Of Colorectal Cancer, Deepak S. Chauhan, Meena Jaggi, Subhash C. Chauhan, Murali M. Yallapu

Research Symposium

Background: Rio Grande Valley experience severe cancer health disparity. A novel therapeutic modality may serve as better therapeutic option. Nanohybrids endowed with multifunctionality, longer circulation time, large surface area have emerged as an active preference for cancer research. However, rising concern of nanomaterials toxicity and scalability issues has slowed their translation to clinics. Exosomes (Exo) are endogenous endocytic origin 40-100 nm vesicles found in various body fluids, which in comparison to synthetic nanoparticles, are biodegradable, highly biocompatible as well as immunocompatible in nature. Although bulk isolation of exosomes from human body fluids is still a problem and engineering of exosomes …

A 3d Printed Microneedle System For Transdermal Drug Delivery Of Anticancer Drugs, Md Jasim Uddin, Tanvir Ahmed, Dennis Douroumis

Research Symposium

Background: Transdermal delivery of drugs is an attractive alternative to the conventional route of administration as oral delivery. The hypodermic injections are painful and less patient compliance. Microneedles (MNs) are micron-sized, minimally invasive needles to deliver a wide range of molecules (e.g., small, DNA, vaccines etc.) to the upper portion of the dermis in a sustained and controlled manner, without causing any pain. The introduction of 3D printing technologies in the fabrication of MN will promote one-step manufacturing tools and scale-up for the delivery devices of anticancer drugs.

Methods: The 3D printed MN (3DMN) arrays were fabricated using Stereolithography (SLA), …

Adaptive Octree Meshes For Simulation Of Extracellular Electrophysiology, Christopher Bc Girard, Dong Song

Engineering Faculty Articles and Research

Objective. The interaction between neural tissues and artificial electrodes is crucial for understanding and advancing neuroscientific research and therapeutic applications. However, accurately modeling this space around the neurons rapidly increases the computational complexity of neural simulations. Approach. This study demonstrates a dynamically adaptive simulation method that greatly accelerates computation by adjusting spatial resolution of the simulation as needed. Use of an octree structure for the mesh, in combination with the admittance method for discretizing conductivity, provides both accurate approximation and ease of modification on-the-fly. Main results. In tests of both local field potential estimation and multi-electrode stimulation, dynamically adapted meshes …

Advanced Processing Techniques For Electrospun Nanofibers: Investigating Annealing And Laser Zone-Drawing Effects On Material Characteristics, Matthew D. Flamini

Theses and Dissertations

Electrospun nanofibers hold potential for a wide range of commercial and scientific applications; however, their properties must be optimized through post-processing treatments to achieve optimal performance. This dissertation investigates the effects of annealing and laser zone-drawing on electrospun nanofiber properties. Annealing polycaprolactone nanofibers at 70°C results in the highest rate of crystallization and molecular alignment, impacting long-term stability and mechanical properties. A multivariate linear model incorporating crystallinity and molecular alignment predicts the material properties resulting from annealing under different conditions. Laser zone-drawing experiments reveal that polylactide fiber thinning under laser irradiation primarily occurs due to drawing rather than ablation. Steady-state …

The Discovery, Characterization, And Engineering Of Autolytic Enzymes As Antimicrobials, Jacob M. Furlon

Dartmouth College Ph.D Dissertations

In an age of rising levels of antibiotic resistance, we are quickly running out of tools to address some of the most virulent and widespread infectious bacteria. One group of enzymes that show significant potential for use as next-generation antibiotics are antimicrobial peptidoglycan hydrolases, often referred to as lysins. These enzymes are responsible for the breakdown of peptidoglycan within the bacterial cell wall, and, when exogenously applied, can result in dramatic destabilization of the cell wall leading to rapid lysis of the bacteria. While phage endolysins have been widely investigated as potential antimicrobials, the therapeutic potential of endogenous autolysins from …

Conduction Mechanism Switching From Coulomb Blockade To Classical Critical Percolation Behavior In Disordered Nanoparticle Array, Abhijeet Prasad, Jay Min Lim, Ravi Saraf

Department of Chemical and Biomolecular Engineering: Faculty Publications

Large, open-gate transistors made from metal nanoparticle arrays offer possibilities to build new electronic devices, such as sensors. A nanoparticle necklace network (N³) of Au particles from 300 K to cryogenic temperatures exhibit a nonohmic I–V_d behavior, I ≈ (V_d–V_T)^𝜻, where V_T is a conduction gap and 𝜻 is a constant critical exponent. The conduction gap in N³, made from disordered networks of 1D chains of 10 nm diameter Au particles exhibits room temperature (RT) gating. Although the I–V_d behavior at RT is identical to Coulomb blockade, …

Automatic Cardiac Mri Image Segmentation And Mesh Generation, Ziyuan Li

McKelvey School of Engineering Graduate Student Theses & Dissertations

Segmenting and reconstructing cardiac anatomical structures from magnetic resonance (MR) images is essential for the quantitative measurement and automatic diagnosis of cardiovascular diseases [1]. However, manual evaluation of the time-series cardiac MRI (CMRI) obtained during routine clinical care are laborious, inefficient, and tends to produce biased and non-reproducible results [2]. This thesis proposes an end-to-end pipeline for automatically segmenting short-axis (SAX) CMRI images and generating high-quality 2D and 3D meshes suitable for finite element analysis. The main advantage of our approach is that it can not only work as a stand-alone pipeline for the automatic CMR image segmentation and mesh …

The Effect Of Slow Strain Rate Tension And Cyclic Loading On Biodegradable Zn–2%Fe–0.8%Mn Alloy In A Simulated Physiological Environment, Lital Ben Tzion-Mottye, Adi Bahar, Tomer Ron, Galit Katarivas Levy, Jeremy Goldman, Dan Eliezer, Eli Aghion

Michigan Tech Publications

Zinc-based alloys have gained increased interest as biodegradable structural materials for medical applications due to their adequate biocompatibility, crucial roles in many physiological functions and attractive antibacterial properties. However, the major drawbacks of zinc alloys relate to their inadequate mechanical properties and tendency to provoke fibrous encapsulation due to relatively high standard potential. Based on the promising effect of Mn on properties of Zn-based alloys, the present study aimed at evaluating the suitability of Zn–2%Fe–0.8%Mn alloy as a potential biodegradable implant under in-vitro conditions. This evaluation focused on the passivation characteristics as determined by cyclic potentiodynamic polarization analysis, immersion test, …

Pine-Tree Enables Efficient Enrichment Of Prime-Edited Hpscs, Mary S. Jia, Christopher E. Nelson

Biomedical Engineering Faculty Publications and Presentations

Commentary

PINE-TREE enables efficient enrichment of prime-edited hPSCs

Bilateral Arm Movements Are Coordinated Via Task-Dependent Negotiations Between Independent And Codependent Control, But Not By A “Coupling” Control Policy, Nick M. Kitchen, Jisung Yuk, Andrzej Przybyla, Robert A. Scheidt, Robert L. Sainburg

Biomedical Engineering Faculty Research and Publications

Prior research has shown that coordination of bilateral arm movements might be attributed to either control policies that minimize performance and control costs regardless of bilateral symmetry or by control coupling, which activates bilaterally homologous muscles as a single unit to achieve symmetric performance. We hypothesize that independent bimanual control (movements of one arm are performed without influence on the other) and codependent bimanual control (two arms are constrained to move together with high spatiotemporal symmetry) are two extremes on a coordination spectrum that can be negotiated to meet infinite variations in task demands. To better understand and distinguish between …

Contribution Of Implicit Memory To Adaptation Of Movement Extent During Reaching Against Unpredictable Spring-Like Loads: Insensitivity To Intentional Suppression Of Kinematic Performance, Devon D. Lantagne, Leigh A. Mrotek, James B. Hoelzle, Danny G. Thomas, Robert A. Scheidt

Psychology Faculty Research and Publications

We examined the extent to which intentionally underperforming a goal-directed reaching task impacts how memories of recent performance contribute to sensorimotor adaptation. Healthy human subjects performed computerized cognition testing and an assessment of sensorimotor adaptation, wherein they grasped the handle of a horizontal planar robot while making goal-directed out-and-back reaching movements. The robot exerted forces that resisted hand motion with a spring-like load that changed unpredictably between movements. The robotic test assessed how implicit and explicit memories of sensorimotor performance contribute to the compensation for the unpredictable changes in the hand-held load. After each movement, subjects were to recall and …

Construction And Performance Optimization Of Bioconjugated Nanosensors For Early Detection Of Breast Cancer And Pro-Inflammatory Diseases, Pooja Gaikwad

Dissertations, Theses, and Capstone Projects

In recent years, nanosensors have emerged as a tool with strong potential in medical diagnostics. Single-walled carbon nanotube (SWCNT) based optical nanosensors have notably garnered interest due to the unique characteristics of their near-infrared fluorescence emission, including tissue transparency, photostability, and various chiralities with discrete absorption and fluorescence emission bands. Additionally, the optoelectronic properties of SWCNT are sensitive to the surrounding environment, which makes them suitable for in vitro and in vivo biosensing. Single-stranded (ss) DNA-wrapped SWCNTs have been reported as optical nanosensors for cancers and metabolic diseases. Breast cancer and cardiovascular diseases are the most common causes of death …

Guar-Based Injectable Hydrogel For Drug Delivery And In Vitro Bone Cell Growth, Humandra Poudel, Ambar R. Rangumagar, Pooja Singh, Adeolu Oluremi, Nawab Ali, Fumiya Watanabe, Joseph Batta-Mpouma, Jin-Woo Kim, Ahona Ghosh, Anindya Ghosh

Chemistry & Biochemistry Faculty Publications and Presentations

Injectable hydrogels offer numerous advantages in various areas, which include tissue engineering and drug delivery because of their unique properties such as tunability, excellent carrier properties, and biocompatibility. These hydrogels can be administered with minimal invasiveness. In this study, we synthesized an injectable hydrogel by rehydrating lyophilized mixtures of guar adamantane (Guar-ADI) and poly-β-cyclodextrin (p-βCD) in a solution of phosphate-buffered saline (PBS) maintained at pH 7.4. The hydrogel was formed via host-guest interaction between modified guar (Guar-ADI), obtained by reacting guar gum with 1-adamantyl isocyanate (ADI) and p-βCD. Comprehensive characterization of all synthesized materials, including the hydrogel, was performed using …

Bacterial Motion And Spread In Porous Environments, Yasser Almoteri

Dissertations

Micro-swimmers are ubiquitous in nature from soil and water to mammalian bodies and even many technological processes. Common known examples are microbes such as bacteria, micro-algae and micro-plankton, cells such as spermatozoa and organisms such as nematodes. These swimmers live and have evolved in multiplex environments and complex flows in the presence of other swimmers and types, inert particles and fibers, interfaces and non-trivial confinements and more. Understanding the locomotion and interactions of these individual micro-swimmers in such impure viscous fluids is crucial to understanding the emergent dynamics of such complex systems, and to further enabling us to control and …

Cell Encapsulation In Gelatin Methacryloyl Bioinks Impairs Microscale Diffusion Properties, Elvan Dogan, Christina Holshue, Anant Bhusal, Roshni Shukla, Amir K. Miri

Henry M. Rowan College of Engineering Departmental Research

Light-assisted bioprinted gelatin methacryloyl (GelMA) constructs have been used for cell-laden microtissues and organoids. GelMA can be loaded by desired cells, which can regulate the biophysical properties of bioprinted constructs. We study how the degree of methacrylation (MA degree), GelMA mass concentration, and cell density change mass transport properties. We introduce a fluorescent-microscopy-based method of biotransport testing with improved sensitivity compared to the traditional particle tracking methods. The diffusion capacity of GelMA with a higher MA significantly decreased compared to a lower MA. Opposed to a steady range of linear elastic moduli, the diffusion coefficient in GelMA varied when cell …

Validation Of A Biomechanical Injury And Disease Assessment Platform Applying An Inertial-Based Biosensor And Axis Vector Computation, Wangdo Kim, Emir A. Vela, Sean S. Kohles, Victor Huayamave

Publications

Inertial kinetics and kinematics have substantial influences on human biomechanical function. A new algorithm for Inertial Measurement Unit (IMU)-based motion tracking is presented in this work. The primary aims of this paper are to combine recent developments in improved biosensor technology with mainstream motion-tracking hardware to measure the overall performance of human movement based on joint axis-angle representations of limb rotation. This work describes an alternative approach to representing three-dimensional rotations using a normalized vector around which an identified joint angle defines the overall rotation, rather than a traditional Euler angle approach. Furthermore, IMUs allow for the direct measurement of …