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Full-Text Articles in Biomedical Engineering and Bioengineering
An Improved Polynomial Chaos Expansion Based Response Surface Method And Its Applications On Frame And Spring Engineering Based Structures, Mhd A. Hafez
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In engineering fields, computational models provide a tool that can simulate a real world response and enhance our understanding of physical phenomenas. However, such models are often computationally expensive with multiple sources of uncertainty related to the model’s input/assumptions. For example, the literature indicates that ligament’s material properties and its insertion site locations have a significant effect on the performance of knee joint models, which makes addressing uncertainty related to them a crucial step to make the computational model more representative of reality. However, previous sensitivity studies were limited due to the computational expense of the models. The high computational …
Thenar Muscle And Transverse Carpal Ligament Relationship, Jeremy Granieri Loss
Thenar Muscle And Transverse Carpal Ligament Relationship, Jeremy Granieri Loss
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The transverse carpal ligament (TCL) acts as a partial origin for the thenar muscles (abductor pollicis brevis (APB), flexor pollicis brevis (FPB), opponens pollicis (OPP)). The attachment between the thenar muscles and TCL implies a relationship between the tissues. The thenar muscles rely on their origins for thumb motion and force production. However, individual thenar origin information is lacking. Further information regarding the anatomical relationship between the individual thenar muscles and TCL may provide insight into thenar muscle function. In addition, the TCL responds to thenar muscle contraction as shown by volar migration of the TCL during various thumb movements. …
Three-Dimensional Human Neural Stem Cell Culture For High-Throughput Assessment Of Developmental Neurotoxicity, Pranav Joshi
Three-Dimensional Human Neural Stem Cell Culture For High-Throughput Assessment Of Developmental Neurotoxicity, Pranav Joshi
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Only a few hundred of compounds, among tens of thousands of commercially available compounds, have been tested for developmental neurotoxicity (DNT) due to the limitations of current guidelines for DNT which are based entirely on in vivo experiments. In vivo studies are highly expensive and time-consuming, which often do not correlate to human outcomes. There is a key gap in our ability to predict in vivo outcomes accurately and robustly using in vitro assays. This is particularly the case for predicting the toxicity of chemicals on the developing human brains. Conventional in vitro assays are typically performed in two-dimensional (2D) …
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
Measurement Of Red Blood Cell Oxygenation State By Magnetophoresis, Nina A. Smith
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Magnetophoresis of red blood cells (RBCs) at varying partial pressures of oxygen (pO2) is hypothesized to rejuvenate stored blood to be utilized beyond the FDA regulated 42-day storage time. Magnetophoresis is a particle or cells motion induced by an applied magnetic field in a viscous media. The average magnetophoretic mobility of an oxygenated RBC is -0.126x10-6 mm3-s/kg, and a deoxygenated RBC is 3.66x10-6 mm3-s/kg, presenting magnetophoresis as a resource for RBC rejuvenation in hopes of storing it longer than 42 days. The main objective of this paper was to determine if controlling the pO2 within an RBC suspension, can singly- …
Feasibility Of Using An Equilibrium Point Strategy To Control Reaching Movements Of Paralyzed Arms With Functional Electrical Stimulation, Matthew Huffman
Feasibility Of Using An Equilibrium Point Strategy To Control Reaching Movements Of Paralyzed Arms With Functional Electrical Stimulation, Matthew Huffman
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Functional electrical stimulation (FES) is a technology capable of improving the quality of life for those with the loss of limb movement related to spinal cord injuries. Individuals with high-level tetraplegia, in particular, have lost all movement capabilities below the neck. FES has shown promise in bypassing spinal cord damage by sending electrical impulses directly to a nerve or muscle to trigger a desired function. Despite advancements in FES, full-arm reaching motions have not been achieved, leaving patients unable to perform fundamental tasks such as eating and grooming. To overcome the inability in current FES models to achieve multi-joint coordination, …
Characterizing The Effects Of High-Intensity Exercise On Balance And Gait Under Dual-Task Conditions In Parkinson’S Disease, El Iva Baron
Characterizing The Effects Of High-Intensity Exercise On Balance And Gait Under Dual-Task Conditions In Parkinson’S Disease, El Iva Baron
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Parkinson’s disease (PD) is a neurodegenerative disorder, characterized by four cardinal motor symptoms including bradykinesia, tremor, rigidity, and postural instability, and non-motor symptoms including cognitive impairment. Daily activities, such as walking and maintaining balance, are impacted due to impairments in motor function, and are further exacerbated with the addition of cognitive loading, or dual-tasking (DT). High-intensity exercise has demonstrated centrally-mediated improvements of PD symptoms, with additional positive effects on overall health. The goal of this project was to identify changes in dynamic balance recovery and gait function under conditions with and without increased cognitive load after a high-intensity exercise intervention …
The Effect Of Cognitive Limb Embodiment On Vascular Physiological Response, Hala Elsir Mustafa Osman
The Effect Of Cognitive Limb Embodiment On Vascular Physiological Response, Hala Elsir Mustafa Osman
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The rubber hand illusion (RHI) is a visual-tactile perceptual illusion commonly used to study body ownership. In this paradigm, a rubber hand is positioned in front of a participant, and the person’s real hand is hidden from sight behind a barrier. When the real hand and the rubber hand are stroked synchronously, individuals perceive the rubber hand as if it were their own; it becomes “embodied.” This illusory experience of body ownership is associated with multimodal integration of touch and vision. From these visual-tactile-cognitive mechanisms, we establish that our hands belong to us when what we see matches what we …
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
High-Throughput Metabolism-Induced Toxicity Assays On A 384-Pillar Plate, Sooyeion Kang
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The U.S Environmental Protection Agency (EPA) launched the Transform Tox Testing Challenge in 2016 with the goal of developing practical methods that can be integrated into conventional high-throughput screening (HTS) assays to better predict the toxicity of parent compounds and their metabolites in vivo. In response to this need and to retrofit existing HTS assays for assessing metabolism-induced toxicity of compounds, we have developed a 384-pillar plate that is complementary to traditional 384-well plates and ideally suited for culturing human cells in three dimensions (3D) at a microscale. Briefly, human embryonic kidney (HEK) 293 cells in a mixture of alginate …
A Synthesis Platform For Temperature Responsive Star Polymers, Schmitt J. Richard Jr.
A Synthesis Platform For Temperature Responsive Star Polymers, Schmitt J. Richard Jr.
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Star polymers are a class of branched polymers comprised of several polymer chains extending from a central point. Star polymers have applications in biopharmaceuticals where they have been proposed to be suitable drug delivery vehicles. Star polymers have traditionally been synthesized through chemical synthesis with added functionality provided by grafting on the arms. This complex synthesis can be simplified by using a biosynthetic approach which enables precise control of molecular weight and composition. This approach is demonstrated using star polymers with arms composed of a temperature responsive protein-based polymer termed elastin-like polypeptide (ELP). Star polymers are characterized based on the …
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
Modeling Liver Diseases Using Hepatic Cell Microarrays, Alexander David Roth
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Hepatocellular carcinoma (HCC) is an invasive and aggressive cancer of the liver that arises due to chronic cirrhosis. Research into understanding HCC has focused on two-dimensional (2D) and three-dimensional (3D) technologies to simulate the liver microenvironment and use animal models to model how HCC affects the rest of the body. 3D hydrogel models are desired because they can mimic the transport behavior observed in vivo by structurally mimicking the extracellular matrix (ECM) without the ethical concerns of animal models. However, hydrogels can be toxic to cells and require optimal procedures for appropriate handling. In this study, we created 3D models …
Cathepsin K Targeting Matrix Regenerative Nanoparticles For Small Abdominal Aortic Aneurysm Repair, Jonathan M. Fox
Cathepsin K Targeting Matrix Regenerative Nanoparticles For Small Abdominal Aortic Aneurysm Repair, Jonathan M. Fox
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Abdominal aortic aneurysms (AAAs) are characterized by the loss of elasticity in the aorta wall leading to a chronic increase in diameter and resulting in rupture. This is due to the lack of regeneration of elastic fibers and chronic proteolytic breakdown of elastic fibers within the aorta mediated by matrix metalloproteinases (MMPs), specifically MMP-2 and -9. Previous studies in our lab have shown cationic amphiphile-surface functionalized poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) loaded with doxycycline (DOX) to inhibit MMP activity and stimulate elastic matrix synthesis, effects we attributed to both low doses (< 10 mg/ml) of DOX released and independent effects of cationic amphiphile pendant groups on the NP surface. This promises application of these NPs to arrest or regress AAA growth since high oral DOX dosing inhibits new elastic matrix formation in the AAA wall and has undesirable side effects. In this study, we investigated feasibility of antibody-based active targeting of intravenously infused NPs to the AAA wall. Cathepsin K, a cysteine protease, is a biomarker for AAA and overexpressed in abdominal aortic aneurysm tissue making it an ideal target moiety. We have shown using a covalent conjugation method of modifying the surface of the NPs with a cathepsin K antibody resulted in a more robust antibody attachment which did not affect the DOX release profile. Cathepsin K expression was confirmed to be localized on the cell surface and utilizing cathepsin K Ab-conjugated NPs, we demonstrated an increased NP localization to the cathepsin K overexpressing cells in vitro and ex vivo. Importantly, the DOX-loaded NPs demonstrated pro-elastogenic and anti-proteolytic effects in aneurysmal smooth muscle cells supporting their use as regenerative therapies to arrest and regress AAA growth. Preliminary data has been collected indicating cathepsin K Ab-conjugated NP targeting to AAAs in elastase-injured rat models. The study outcomes support the feasibility of using cathepsin K Ab-conjugated NPs as a targeted therapy for elastic matrix regeneration in AAA tissue and will serve as a basis for already initiated follow up studies to assess NP biodistribution, in situ retention in the AAA wall, and safety as a function of time.
C-Jun N-Terminal Kinase Inhibitory Nanotherapeutics For Regenerative Elastic Matrix Repair In Abdominal Aortic Aneurysms, Andrew T. Camardo
C-Jun N-Terminal Kinase Inhibitory Nanotherapeutics For Regenerative Elastic Matrix Repair In Abdominal Aortic Aneurysms, Andrew T. Camardo
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Abdominal aortic aneurysms (AAA) are localized expansions of the aorta wall that continue to grow until they reach a critical size and fatally rupture. This growth is driven by the chronic disruption, degradation, and subsequent loss of aortal wall elastic fibers by matrix metalloproteinases (MMPs) secreted by inflammatory cells recruited to the aorta wall following an injury stimulus, and the inherent inability of vascular smooth muscle cells (SMCs) to naturally repair or regenerate elastic fibers. This leads to a net loss of elastic matrix and the continuing weakening of the aortal wall until eventual rupture. Current treatments seek to reinforce …
Design And Control Of A Powered Rowing Machine With Programmable Impedance, Jose Humberto De La Casas Zolezzi
Design And Control Of A Powered Rowing Machine With Programmable Impedance, Jose Humberto De La Casas Zolezzi
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Due to the rise of obesity, diabetes and cardiovascular disease, research in human performance and physical activity has received increased attention. Rowing machines are used for performance improvements through concentric exercises, however a combination of concentric and eccentric actions is known to improve the effectiveness of training. In this work, a conventional rowing machine was modified to include an electric motor and a robust impedance control system, enabling programmable impedance with concentric and eccentric capabilities. Eccentric exercises are known to contribute significantly to the efficacy of training and to diminish the detrimental effects of humans operating in microgravity for long …
Decitabine-Loaded Nanogel Treatment To Reverse Cancer Drug Resistance, Samantha A. Cramer
Decitabine-Loaded Nanogel Treatment To Reverse Cancer Drug Resistance, Samantha A. Cramer
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Cancers in which epigenetic changes, such as hypermethylation of DNA, lead to drug resistance cause the cancer to become unresponsive to existing chemotherapeutic treatments. The epigenetic drug – 5-aza-2’-deoxycytidine (decitabine, DAC) – is a potent hypomethylating agent, but its effect is transient due to its instability. Previous studies have shown that loading DAC into nanogel significantly enhances its antiproliferative effect (compared to DAC in solution) in drug-resistant breast cancer cells (MCF-7/ADR). Further, the previous studies demonstrated changes in the membrane lipid profile of resistant cells following treatment with DAC either as solution or in nanogels. The objective of the present …
Design And Production Of A Hydrogel Forming Polypeptide: Engaging High School Students In Protein Design, James K. Deyling
Design And Production Of A Hydrogel Forming Polypeptide: Engaging High School Students In Protein Design, James K. Deyling
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Bioinks are a class of hydrogel that have the potential to be the ink used in the creation of printed organs, connective tissue, and other important structures within the body. One class of material that may be a suitable bioink hydrogel is elastin-like polypeptides (ELPs), which are synthetic biopolymers inspired by the naturally existing connective tissue elastin. ELPs consist of a repeat pentapeptide sequence (GXGVP)n, where X is any of the 20 naturally existing amino acids other than proline. These biomolecules are capable of exhibiting environmental responsiveness when exposed to certain stimulus such as salt concentration, temperature, and pH, depending …
Potential Optimal Gait Performance Of Mauch S-N-S Prosthetic Knee Configurations As Predicted By Dynamic Modeling, Chih-Hao Chien
Potential Optimal Gait Performance Of Mauch S-N-S Prosthetic Knee Configurations As Predicted By Dynamic Modeling, Chih-Hao Chien
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Patients with prosthetic legs routinely suffer from abnormal gait patterns which can cause health issues and eventually lower the quality of their lives. Despite the half-century advance in the technology of prosthetic knees, from the purely mechanical to microprocessor controlled systems, patient testing suggests that very little progress has been made in the quality of the kinetics and kinematics of amputee gait. Moreover, the cost of microprocessor controlled prosthetic knees may be 10 times more than the purely mechanical knees. While prosthetic knees have become more complex and expensive, it is not proven that the prosthetic knee is a central …
Human Hair Keratin Protein, Hair Fibers And Hydroxyapatite (Ha) Composite Scaffold For Bone Tissue Regeneration, Samuel Siyum
Human Hair Keratin Protein, Hair Fibers And Hydroxyapatite (Ha) Composite Scaffold For Bone Tissue Regeneration, Samuel Siyum
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The field of tissue engineering aims at promoting the regeneration of tissues or replacement of failing or malfunctioning tissue by means of combining a scaffold material, adequate cells and bioactive molecules. Different materials have been proposed for use as three-dimensional porous scaffolds for bone tissue engineering procedures. Among them, polymers of natural origin are one of the most attractive options mainly due to their similarities with the extracellular matrix (ECM), chemical versatility as well as typically good biological performance. In this study, two biocompatible composite scaffolds were developed from natural polymer by tissue engineering approach and tested in vitro. The …
Validation Of An Accelerometry Based Method Of Human Gait Analysis, Obinna Nwanna
Validation Of An Accelerometry Based Method Of Human Gait Analysis, Obinna Nwanna
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Gait analysis is the quantification of locomotion. Understanding the science behind the way we move is of interest to a wide variety of fields. Medical professionals might use gait analysis to track the rehabilitation progress of a patient. An engineer may want to design wearable robotics to augment a human operator. Use cases even extend into the sport and entertainment industries. Typically, a gait analysis is performed in a highly specialized laboratory containing cumbersome expensive equipment. The process is tedious and requires specially trained operators. Continued development of small and cheap inertial measurement units (IMUs) over an alternative to current …
Biomechanics Of Prosthetic Knee Systems : Role Of Dampening And Energy Storage Systems, Hande Argunsah Bayram
Biomechanics Of Prosthetic Knee Systems : Role Of Dampening And Energy Storage Systems, Hande Argunsah Bayram
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One significant drawback of the commercial passive and microprocessored prosthetic devices, the inability of delivering positive energy when needed, is due to the absence of the knee flexion during stance phase. Moreover, consequences such as circumduction and disturbed gait pattern take place due to the improper energy flow at the knee and the absence of the positive energy delivery during the swing phase. Current generation powered design has solved these problems by delivering the needed energy with heavy battery demanding motors, which increase the mass of the device significantly. Hence, the gait quality of transfemoral amputees has not improved significantly …
Scalp Eeg And Tms Based Electrophysiological Study Of Brain Function Of Motor Control In Aging, Mehmed Satuk Bayram
Scalp Eeg And Tms Based Electrophysiological Study Of Brain Function Of Motor Control In Aging, Mehmed Satuk Bayram
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Voluntary movements of human body are controlled by the brain through corticomuscular pathways. Although neuromuscular control mechanisms of voluntary movements have been studied extensively, many remain to be learned, especially neuromuscular adaptations related to clinical conditions such as neurological disorders and aging. This research aims at a better understanding of functional connection between the brain and muscle during voluntary motor activities in aging and the extent to which this connection can be changed by training the neuromuscular system. Three research projects were conducted to achieve this aim. The analyses in the first two projects are based on comparisons of non-invasive …
A Robotic Neuro-Musculoskeletal Simulator For Spine Research, Robb W. Colbrunn
A Robotic Neuro-Musculoskeletal Simulator For Spine Research, Robb W. Colbrunn
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An influential conceptual framework advanced by Panjabi represents the living spine as a complex neuromusculoskeletal system whose biomechanical functioning is rather finely dependent upon the interactions among and between three principal subsystems: the passive musculoskeletal subsystem (osteoligamentous spine plus passive mechanical contributions of the muscles), the active musculoskeletal subsystem (muscles and tendons), and the neural and feedback subsystem (neural control centers and feedback elements such as mechanoreceptors located in the soft tissues) [1]. The interplay between subsystems readily encourages "thought experiments" of how pathologic changes in one subsystem might influence another--for example, prompting one to speculate how painful arthritic changes …
A Microfluidic Platform To Quantify Spatio-Temporal Diffusion Of Chemo-Gradients Within 3d Scaffolds: Applications In Axonal Biology, Michael A. Sawonik
A Microfluidic Platform To Quantify Spatio-Temporal Diffusion Of Chemo-Gradients Within 3d Scaffolds: Applications In Axonal Biology, Michael A. Sawonik
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Axonal outgrowth and guidance play an important role in wiring the developing and regenerating nervous system. The critical role of biomolecular gradients in facilitating this axonal sensitivity and directionality along specific trajectories needs to be elucidated for designing effective therapeutic treatments under injury or disease conditions. However, previous in vitro approaches based on micropipette assay or gel-turning assay proved to be unsuitable or inefficient for precise generation and quantification of diffusive gradients. In this study, we utilized a microfluidic device to generate and quantify physiologically-relevant biomolecular gradients in a simple and reliable manner. Using a combination of computational and experimental …
In Vitro Biomechanical Testing And Computational: Modeling In Spine, Mageswaran Prasath
In Vitro Biomechanical Testing And Computational: Modeling In Spine, Mageswaran Prasath
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Two separate in vitro biomechanical studies were conducted on human cadaveric spines (Lumbar) to evaluate the stability following the implantation of two different spinal fixation devices interspinous fixation device (ISD) and Hybrid dynamic stabilizers. ISD was evaluated as a stand-alone and in combination with unilateral pedicle rod system. The results were compared against the gold standard, spinal fusion (bilateral pedicle rod system). The second study involving the hybrid dynamic system, evaluated the effect on adjacent levels using a hybrid testing protocol. A robotic spine testing system was used to conduct the biomechanical tests. This system has the ability to apply …