Vena Cava As An Alternative To Pericardium In Bioprosthetic Percutaneous Heart Valves, 2010 Clemson University
Vena Cava As An Alternative To Pericardium In Bioprosthetic Percutaneous Heart Valves, Amy Munnelly
Valve disease is a specialized form of cardiovascular disease that specifically affects the heart valves. Heart valves serve the vital function of maintaining unidirectional blood flow through the chambers of the heart during the cardiac cycle; however, as valve disease progresses, this function can become severely compromised . Currently, the only cure for valve disease is to replace the defective valve with an engineered substitute. Each year, over 300,000 heart valve replacement surgeries are performed worldwide , and this number is expected to continue growing as life expectancies increase .
In the United States, the most common form of valve …
Neomycin-Enhanced Carbodiimide Cross-Linking For Glycosaminoglycan Stability In Bioprosthetic Heart Valves, Joshua Leong
Valvular heart diseases lead to over 290,000 heart valve replacements worldwide each year, and approximately half of these involve replacement with a bioprosthetic heart valve (BHV) . BHVs exhibit excellent hemocompatibility, but suffer from inadequate long-term durability with most adult implanted valves failing within 12 to 15 years after implantation . Although this may be adequate for some individuals, BHV implantation may be contraindicated in younger individuals to avoid reoperation. Even in elder recipients, valve dysfunction can still cause death or reoperation that could be avoided with increased BHV durability. Therefore, investigation into methods of increasing BHV durability can not …
An Investigation Of Process Parameters To Optimize The Fiber Diameter Of Electrospun Vascular Scaffolds Through Experimental Design, 2010 California Polytechnic State University, San Luis Obispo
An Investigation Of Process Parameters To Optimize The Fiber Diameter Of Electrospun Vascular Scaffolds Through Experimental Design, Steffi Wong
No abstract provided.
Characterization And Analysis Techniques Of A Dynamic In Vitro Blood-Brain Barrier Model, 2010 California Polytechnic State University, San Luis Obispo
Characterization And Analysis Techniques Of A Dynamic In Vitro Blood-Brain Barrier Model, Ryan Everett Woodhouse
The blood-brain barrier (BBB) is responsible for maintaining the sensitive environment required by the brain. Although the BBB is necessary for proper functioning of the brain, it acts as an obstacle for doctors attempting to treat neurological disease. For a drug to act upon the brain, it must first pass through the discriminating BBB. For this reason, much research has been performed in recent years in order to create an in vitro model of the BBB on which drugs targeted for the central nervous system may be tested. The main goal of this project is to create an in vitro …
New Tools For Monitoring Gamma Camera Uniformity, 2010 University of Texas Graduate School of Biomedical Sciences at Houston
New Tools For Monitoring Gamma Camera Uniformity, Brad K. Lofton
The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences Dissertations and Theses (Open Access)
Detector uniformity is a fundamental performance characteristic of all modern gamma camera systems, and ensuring a stable, uniform detector response is critical for maintaining clinical images that are free of artifact. For these reasons, the assessment of detector uniformity is one of the most common activities associated with a successful clinical quality assurance program in gamma camera imaging. The evaluation of this parameter, however, is often unclear because it is highly dependent upon acquisition conditions, reviewer expertise, and the application of somewhat arbitrary limits that do not characterize the spatial location of the non-uniformities. Furthermore, as the goal of any …
Evaluation Of Factors That Modulate Cellular Adipogenesis For Breast Tissue Engineering Strategies, 2010 Clemson University
Evaluation Of Factors That Modulate Cellular Adipogenesis For Breast Tissue Engineering Strategies, Cheryl Gomillion
It is estimated that this year more than 200,000 women in the United States will be diagnosed with breast cancer. Treatment for most occurrences of breast cancer will often include surgical removal of the tumorigenic tissue, resulting in a soft tissue defect within the subcutaneous tissue of the skin. Post-surgical reconstruction methods are often sought by patients to restore the aesthetic function of the breast via cellular or non-cellular methods; however, because of complications associated with currently used methods for breast reconstruction, researchers are investigating tissue engineering methods to produce viable autologous adipose tissue for breast reconstruction.
Previous research in …
Novel Vascular Grafts Based On Polyphenol-Stabilized Acellular Tissue Scaffolds, 2010 Clemson University
Novel Vascular Grafts Based On Polyphenol-Stabilized Acellular Tissue Scaffolds, Ting-Hsien Chuang
The Cardiovascular diseases (CVDs) continue to be the leading cause of morbidity and mortality worldwide. The most common form of CVDs is occlusion of blood flow thus limiting blood supply to specific tissues or organs. Atherosclerosis is a leading cause of coronary heart disease and stroke, which were responsible for more than 25% of deaths in 2004.
The demand for vascular graft is huge. In United States alone, approximately 500,000 coronary artery bypass graft surgeries are performed annually. Synthetic polymers such as Dacron and ePTFE have been successfully applied in large diameter blood vessel prosthesis; however, for small diameter (inner …
Characterization Of Anti-Proteolytic And Anti-Proliferative Activities Of Pentagalloylglucose; Its Potential Application As A Therapeutic Agent In Vascular Diseases, Chaitra Cheluvaraju
Cardiovascular diseases are the leading causes of mortality in the United States and will cost around $500 billion this year alone. Elevated proteolytic activity, increased proliferation and migration of vascular smooth muscle cells are hallmarks of atherosclerosis, stenosis and aortic aneurysms. These diseases often manifest the transdifferentiation of vascular smooth muscle cells into osteoblast-like cells followed by deposition of hydroxyapatite–like mineral in the arterial walls.
Currently, there are no standard treatments available for vascular calcification or aneurysms. Atherosclerosis treatment options are limited to statins while balloon angioplasty and stenting – surgical procedures for stenosis, often end in restenosis. Therefore, we …
Characterization And Evaluation Of A Novel Tissue Engineered Aortic Heart Valve Construct, 2010 Clemson University
Characterization And Evaluation Of A Novel Tissue Engineered Aortic Heart Valve Construct, Mary Tedder
Tissue engineering holds great promise for treatment of valvular diseases. Scaffolds for engineered heart valves must function immediately after implantation, but must also permit repopulation with autologous host cells and facilitate gradual remodeling.
Native aortic heart valves are composed of three layers, i.e. two strong external fibrous layers (ventricularis and fibrosa) separated by a central, highly hydrated spongiosa. The fibrous layers provide strength and resilience while the spongiosa layer facilitates shearing of the external layers. Our working hypothesis is that partially cross-linked collagen scaffolds that closely mimic the layered histo-architecture of the native valve would fulfill these requirements. To test …
Modulated Properties Of Fully Absorbable Bicomponent Meshes, 2010 Clemson University
Modulated Properties Of Fully Absorbable Bicomponent Meshes, Shawn Peniston
Current meshes used for soft-tissue repair are mostly composed of single component, nonabsorbable yarn constructions, limiting the ability to modulate their properties. This situation has left the majority of soft tissue repair load-bearing applications to suffer distinctly from undesirable features associated, in part, with mesh inability to (1) possess short-term stiffness to facilitate tissue stability during the development of wound strength; (2) gradually transfer the perceived mechanical load as the wound builds mechanical integrity; and (3) provide compliance with load transfer to the remodeling and maturing mesh/tissue complex. The likelihood of long-term complications is reduced for fully absorbable systems with …
Experimental And Computational Analysis Of An Energy Storage Composite Ankle Foot Orthosis, 2010 University of Nevada, Las Vegas
Experimental And Computational Analysis Of An Energy Storage Composite Ankle Foot Orthosis, Michelle C. Hawkins
UNLV Theses, Dissertations, Professional Papers, and Capstones
Ankle Foot Orthotics (AFOs) are used by individuals presenting with Charcot-Marie-Tooth (CMT) to assist with improving gait. Mitch Warner, CPO, has developed a composite AFO made from woven carbon-Kevlar and carbon fiber lamina. The overall goals of the research are to characterize the HELIOS brace and to determine its effect on the gait of CMT subjects. Human motion analysis, experimental mechanical testing, and Finite Element Analysis (FEA) are used to gain a better understanding of how the materials and geometric design of the HELIOS AFO contribute to gait.
Human motion experiments are performed to determine the relationship between ground reaction …
Development Of Software To Estimate Pressures On The Residual Limbs Of Amputees By Means Of A Pylon Mounted Transducer, 2010 University of Nevada, Las Vegas
Development Of Software To Estimate Pressures On The Residual Limbs Of Amputees By Means Of A Pylon Mounted Transducer, Malli K. Yalamanchili
UNLV Theses, Dissertations, Professional Papers, and Capstones
The alignment of prosthesis has been recognized as one of the main factors that determine successful prosthetic outcomes for trans-tibial amputees. Alignment is defined as the relative position and orientation of the prosthetic components. Misalignment can result in changes in the position and orientation of the joints of the leg and moments experienced by them during gait, increases in energy use, and discomfort or even tissue breakdown at the socket/stump interface. Hence it is very important to align the prosthesis in correct manner. Gait analysis can be used to examine the effects of incorrect alignment of the prosthesis during gait. …
Singular Value Decomposition Metrics Show Limitations Of Detector Design In Diffuse Fluorescence Tomography, Frederic Leblond, Kenneth M. Tichauer, Brian W. Pogue
The spatial resolution and recovered contrast of images reconstructed from diffuse fluorescence tomography data are limited by the high scattering properties of light propagation in biological tissue. As a result, the image reconstruction process can be exceedingly vulnerable to inaccurate prior knowledge of tissue optical properties and stochastic noise. In light of these limitations, the optimal source-detector geometry for a fluorescence tomography system is non-trivial, requiring analytical methods to guide design. Analysis of the singular value decomposition of the matrix to be inverted for image reconstruction is one potential approach, providing key quantitative metrics, such as singular image mode spatial …
The Development And Validation Of A Finite Element Model Of A Canine Rib For Use With A Bone Remodeling Algorithm., 2010 California Polytechnic State University, San Luis Obispo
The Development And Validation Of A Finite Element Model Of A Canine Rib For Use With A Bone Remodeling Algorithm., Scott J. Sylliaasen
Studies are currently being performed to determine the effects of bisphosphonate treatments on the structure and density of bone tissue. One of the pathways for gaining a better understanding of the effects of this and other treatments involves creating a computer simulation. Theory suggests that bone tissue structure and density are directly related to the manner in which the tissue is loaded. Remodeling is the process in which bone tissue is resorbed in areas of low stress distributions, and generated in areas of high stress distributions. Previous studies have utilized numerical methods and finite element methods to predict bone structure …
Correction To Mitochondrial Free [Ca2+] Increases During Atp/Adp Antiport And Adp Phosphorylation: Exploration Of Mechanisms, 2010 Medical College of Wisconsin
Correction To Mitochondrial Free [Ca2+] Increases During Atp/Adp Antiport And Adp Phosphorylation: Exploration Of Mechanisms, Johan Haumann, Ranjan K. Dash, David F. Stowe, Age D. Boelens, Daniel A. Beard, Amadou K.S. Camara
Biomedical Engineering Faculty Research and Publications
No abstract provided.
Synthesis And Characterization Of Diamond-Like Carbon Thin Films For Biomedical Applications, Russell Lee Leonard
Diamond-like carbon (DLC) thin films were produced by pulsed laser deposition (PLD) on silicon, fused silica, and silicon nitride substrates. The films produced were either undoped, made using a pure graphite target, or doped, using multi-component targets made from a combination of graphite and silicon, silicon nitride, titanium dioxide, or silicon monoxide. These films were evaluated for their potential use in biomedical applications, including coatings for artificial joints, heart stents, and bronchoscopes. The films were characterized by Raman spectroscopy, atomic force microscopy, ball-on-flat tribometry, contact angle measurements, and spectrophotometry. Film thickness was determined by optical profilometry. Film adhesion was checked …
Aortic Coarctation: Recent Developments In Experimental And Computational Methods To Assess Treatments For This Simple Condition, John F. Ladisa, Charles A. Taylor, Jeffrey A. Feinstein
Biomedical Engineering Faculty Research and Publications
Coarctation of the aorta (CoA) is often considered a relatively simple disease, but long-term outcomes suggest otherwise as life expectancies are decades less than in the average population and substantial morbidity often exists. What follows is an expanded version of collective work conducted by the authors' and numerous collaborators that was presented at the 1st International Conference on Computational Simulation in Congenital Heart Disease pertaining to recent advances for CoA. The work begins by focusing on what is known about blood flow, pressure and indices of wall shear stress (WSS) in patients with normal vascular anatomy from both clinical imaging …
Assessment Of Morphology And Hemodynamics In Normal And Remodeled Microvasculature With Parameter Sensitivity Analysis, 2010 California Polytechnic State University, San Luis Obispo
Assessment Of Morphology And Hemodynamics In Normal And Remodeled Microvasculature With Parameter Sensitivity Analysis, Shilpi Ghosh
The goal of this study was to compare the morphological and hemodynamic characteristics of normal and remodeled vascular networks in the mouse gracilis muscle. To this end, previously developed models to assess flows and vascular branching were used to assess the normal and remodeled microcirculatory networks. The analysis revealed that the average individual vessel flow rates for vessels of similar caliber and total volumetric flow rates in the networks do not change for vessels of the same caliber after remodeling. Connectivity changes and average diameters primarily change in the larger arterioles after remodeling. A few correlations could be made between …
Microbiorobots For Single Cell Manipulation, 2010 University of Pennsylvania
Microbiorobots For Single Cell Manipulation, Mahmut Selman Sakar
Publicly Accessible Penn Dissertations
One of the great challenges in nano and micro scale science and engineering is the independent manipulation of biological cells and small man-made objects with active sensing. For such biomedical applications as single cell manipulation, telemetry, and localized targeted delivery of chemicals, it is important to fabricate microstructures that can be powered and controlled without a tether in fluidic environments. These microstructures can be used to develop microrobots that have the potential to make existing therapeutic and diagnostic procedures less invasive.
Actuation can be realized using various different organic and inorganic methods. Previous studies explored different forms of actuation and …
Molecular Dynamics Simulation Of Fractal Aggregate Diffusion, 2010 Iowa State University
Molecular Dynamics Simulation Of Fractal Aggregate Diffusion, Gaurav Pranami, Monica H. Lamm, R. Dennis Vigil
R. Dennis Vigil
The diffusion of fractal aggregates constructed with the method by Thouy and Jullien [J. Phys. A 27, 2953 (1994)] comprised of Np spherical primary particles was studied as a function of the aggregate mass and fractal dimension using molecular dynamics simulations. It is shown that finite-size effects have a strong impact on the apparent value of the diffusion coefficient (D), but these can be corrected by carrying out simulations using different simulation box sizes. Specifically, the diffusion coefficient is inversely proportional to the length of a cubic simulation box, and the constant of proportionality appears to be independent of …