Lipids And Collagen Matrix Restrict The Hydraulic Permeability Within The Porous Compartment Of Adult Cortical Bone, Demin Wen, Caroline Androjna, Amit Vasanji, Joanne M. Belovich, Ronald J. Midura
Chemical & Biomedical Engineering Faculty Publications
In vivo the hydraulic permeability of cortical bone influences the transport of nutrients, waste products and signaling molecules, thus influencing the metabolic functions of osteocytes and osteoblasts. In the current study two hypotheses were tested: the presence of (1) lipids and (2) collagen matrix in the porous compartment of cortical bone restricts its permeability. Our approach was to measure the radial permeability of adult canine cortical bone before and after extracting lipids with acetone-methanol, and before and after digesting collagen with bacterial collagenase. Our results showed that the permeability of adult canine cortical bone was below 4.0 × 10−17 ...
Controlling Nonviral Gene Delivery Through The Cell-Biomaterial Interface, 2010 University of Nebraska at Lincoln
Controlling Nonviral Gene Delivery Through The Cell-Biomaterial Interface, Beth A. Duensing
Biological Systems Engineering--Dissertations, Theses, and Student Research
Controlling Nonviral Gene Delivery through the Cell-Biomaterial Interface
Beth Ann Duensing, M.S. University of Nebraska, 2010
Adviser: Angela Pannier
Cell-biomaterial interactions and the corresponding cellular behaviors are poorly understood. Therefore, in this study, the ability of biomaterial surface properties to control nonviral gene delivery was investigated through surface chemistry and protein adsorption and subsequently correlated to cellular behaviors controlled by cell-biomaterial interactions. Self-assembled monolayers (SAMs) of alkanethiols on gold were used as model biomaterials to investigate the effect of surface properties on nonviral gene transfer to cells adhered to these surfaces. SAMs presenting terminal CH3, OH, COO-, and ...
Height Adjustment In Assessing Dual Energy X-Ray Absorptiometry Measurements Of Bone Mass And Density In Children, 2010 Wright State University - Main Campus
Height Adjustment In Assessing Dual Energy X-Ray Absorptiometry Measurements Of Bone Mass And Density In Children, Babette S. Zemel, Mary B. Leonard, Andrea Kelly, Joan M. Lappe, Vicente Gilsanz, Sharon Oberfield, Soroosh Mahboubi, John A. Shepherd, Thomas N. Hangartner, Margaret M. Frederick, Karen K. Winer, Heidi J. Kalkwarf
Biomedical, Industrial & Human Factors Engineering Faculty Publications
Context: In children, bone mineral content (BMC) and bone mineral density (BMD) measurements by dual-energy x-ray absorptiometry (DXA) are affected by height status. No consensus exists on how to adjust BMC or BMD (BMC/BMD) measurements for short or tall stature.
Objective: The aim of this study was to compare various methods to adjust BMC/BMD for height in healthy children.
Design: Data from the Bone Mineral Density in Childhood Study (BMDCS) were used to develop adjustment methods that were validated using an independent cross-sectional sample of healthy children from the Reference Data Project (RDP).
Setting: We conducted the study ...
One-Pot Enzymatic Synthesis Of Deoxy-Thymidine-Diphosphate (Tdp)-2-Deoxy-∝-D-Glucose Using Phosphomannomutase, 2010 Seoul National University
One-Pot Enzymatic Synthesis Of Deoxy-Thymidine-Diphosphate (Tdp)-2-Deoxy-∝-D-Glucose Using Phosphomannomutase, Yung-Hum Yang, Young Bok (Abraham) Kang, Dae-Hee Kim, Tek-Hyung Lee, Sung-Hee Park, Kwangwon Lee, Dongwon Yoo, Kwang-Kyung Liou, Hee-Chan Lee, Jae-Kyung Sohng, Byung-Gee Kim
Faculty Publications - Biomedical, Mechanical, and Civil Engineering
Production of deoxy-thymidine-diphosphate (TDP)-sugars as substrates of glycosyltransferases, has been one of main hurdles for combinatorial antibiotic biosynthesis, which combines sugar moiety with aglycon of various antibiotics. Here, we report the one-pot enzymatic synthesis of TDP-2-deoxy-glucose employing high efficient TMP kinase (TMK; E.C. 220.127.116.11), acetate kinase (ACK; E.C. 18.104.22.168), and TDP-glucose synthase (TGS; E.C. 22.214.171.124) with phosphomannomutase (PMM; E.C. 126.96.36.199). In this study, replacing phosphoglucomutase (PGM; E.C. 5.4.2) by PMM from Escherichia coli gave four times higher specific activity on ...
Electrically Mediated Delivery Of Plasmid Dna To The Skin, Using A Multielectrode Array, 2010 Old Dominion University
Electrically Mediated Delivery Of Plasmid Dna To The Skin, Using A Multielectrode Array, Richard Heller, Yolmari Criz, Loree C. Heller, Richard A. Gilbert, Mark J. Jaroszeski
The easy accessibility of skin makes it an excellent target for gene transfer protocols. To take full advantage of skin as a target for gene transfer, it is important to establish an efficient and reproducible delivery system. Electroporation is a strong candidate to meet this delivery criterion. Electroporation of the skin is a simple, direct, in vivo method to deliver genes for therapy. Previously, delivery to the skin was performed by means of applicators with relatively large distances between electrodes, resulting in significant muscle stimulation and pain. These applicators also had limitations in controlling the directionality of the applied field ...
Links With Canada Benefit Dit Prosthesis Research, 2010 Technological University Dublin
Links With Canada Benefit Dit Prosthesis Research, Colm O'Kane
Colm O’Kane is a lecturer in the School of Manufacturing and Design Engineering and a member of the DIT Biomedical Device and Assistive Technology Research Group. He is currently engaged in PhD research in the field of knee prosthesis development, focused on developing optimised strategies for partial and total joint replacements used in treatment of osteoarthritis of the knee joint. This article is an account of a research scholarship sponsored by the CHC Helicopter Corporation and awarded by the Ireland Canada University Foundation (ICUF). This foundation awards annual scholarships for research visits between Ireland and Canada with the aspiration ...
Crystallization Of Community-Acquired Respiratory Distress Syndrome Toxin From Mycoplasma Pneumonia, 2010 Old Dominion University
Crystallization Of Community-Acquired Respiratory Distress Syndrome Toxin From Mycoplasma Pneumonia, Olga N. Pakhomova, Alexander B. Taylor, Argentina Becker, Stephen P. Holloway, T. R. Kannan, Joel B. Baseman, P. John Hart
Community-acquired respiratory distress syndrome toxin (CARDS TX) is a 591-amino-acid protein with ADP-ribosyltransferase and vacuolating activities that damages the cells lining the respiratory tracts of patients infected with the bacterial pathogen Mycoplasma pneumoniae. Crystals of CARDS TX were grown in space group C2, with unit-cell parameters a = 191.4, b = 107.4, c = 222.1 A, beta = 90.6 degrees. A complete 2.2 A data set was obtained from a single CARDS TX crystal.
St Monitoring On The Programmer For Implantable Cardioverter Devices, 2010 California Polytechnic State University, San Luis Obispo
St Monitoring On The Programmer For Implantable Cardioverter Devices, Sarina Satya
Cardiovascular disease is one of the most prevalent causes of death which has a high mortality rate. If identified early and treated appropriately, the mortality in patients with cardiovascular disease can be hugely reduced. For several decades, 12-Lead ECG has been the standard technique used to identify ischemia, and recent studies have shown that intracardiac electrogram has many benefits over external monitoring such as holter. ST Monitoring feature has been added to St. Jude Medical intracardiac cardioverter defibrillators (ICD) to leverage the ECG technology for identifying cardiovascular disease. This algorithm monitors the intracardiac electrogram to detect and report patterns which ...
Mitochondrial Matrix K+ Flux Independent Of Large-Conductance Ca2+-Activated K+ Channel Opening, 2010 Medical College of Wisconsin
Mitochondrial Matrix K+ Flux Independent Of Large-Conductance Ca2+-Activated K+ Channel Opening, Mohammed Aldakkak, David F. Stowe, Qunli Cheng, Wai-Meng Kwok, Amadou K.S. Camara
Biomedical Engineering Faculty Research and Publications
Large-conductance Ca2+-activated K+ channels (BKCa) in the inner mitochondrial membrane may play a role in protecting against cardiac ischemia-reperfusion injury. NS1619 (30 μM), an activator of BKCa channels, was shown to increase respiration and to stimulate reactive oxygen species generation in isolated cardiac mitochondria energized with succinate. Here, we tested effects of NS1619 to alter matrix K+, H+, and swelling in mitochondria isolated from guinea pig hearts. We found that 30 μM NS1619 did not change matrix K+, H+, and swelling, but that 50 and 100 μM NS1619 caused a concentration-dependent increase in matrix K+ influx ...
Dynamic Failure Properties Of The Porcine Medial Collateral Ligament-Bone Complex For Predicting Injury In Automotive Collisions., 2010 Worcester Polytechnic Institute
Dynamic Failure Properties Of The Porcine Medial Collateral Ligament-Bone Complex For Predicting Injury In Automotive Collisions., Kristen Billiar, Louis Peck, Malcolm Ray
Kristen L. Billiar
The goal of this study was to model the dynamic failure properties of ligaments and their attachment sites to facilitate the development of more realistic dynamic finite element models of the human lower extremities for use in automotive collision simulations. Porcine medial collateral ligaments were chosen as a test model due to their similarities in size and geometry with human ligaments. Each porcine medial collateral ligament-bone complex (n = 12) was held in a custom test fixture placed in a drop tower to apply an axial impulsive impact load, applying strain rates ranging from 0.005 s(-1) to 145 s ...
The Effect Of Ace Inhibition On The Pulmonary Vasculature In Combined Models Of Chronic Hypoxia And Pulmonary Arterial Banding In Sprague Dawley Rats, Shanelle Clarke, Shelley Baumgardt, Robert C. Molthen
Biomedical Engineering Faculty Research and Publications
Microfocal CT was used to image the pulmonary arterial (PA) tree in rodent models of pulmonary hypertension (PH). CT images were used to measure the arterial tree diameter along the main arterial trunk at several hydrostatic intravascular pressures and calculate distensibility. High-resolution planar angiographic imaging was also used to examine distal PA microstructure. Data on pulmonary artery tree morphology improves our understanding of vascular remodeling and response to treatments. Angiotensin II (ATII) has been identified as a mediator of vasoconstriction and proliferative mitotic function. ATII has been shown to promote vascular smooth muscle cell hypertrophy and hyperplasia as well as ...
Predicting Neointimal Hyperplasia In Stented Arteries Using Time-Dependant Computational Fluid Dynamics: A Review, 2010 Technological University Dublin
Predicting Neointimal Hyperplasia In Stented Arteries Using Time-Dependant Computational Fluid Dynamics: A Review, Jonathan Murphy, Fergal Boyle
This paper reviews the recent literature regarding the time-dependant computational fluid dynamics (CFD) analyses of blood flow through implanted coronary stents. The in vivo processes which result in arterial restenosis are identified. The definition and range of the computationally predicted variables which are believed to stimulate the restenosis processes are evaluated. The reviewed literature is subdivided into effect-based in which the effects of altering the flow model are investigated and design-based in which different geometric stent configurations are compared. Finally, conclusions are made regarding the body of work reviewed and recommendations are provided for future work in this field.
Quantitative Assessment Of Sample Stiffness And Sliding Friction From Force Curves In Atomic Force Microscopy, 2010 Worcester Polytechnic Institute
Quantitative Assessment Of Sample Stiffness And Sliding Friction From Force Curves In Atomic Force Microscopy, Nancy Burnham, Jon Pratt, Gordon Shaw, Lee Kumanchik
Nancy A. Burnham
It has long been recognized that the angular deflection of an atomic force microscope(AFM) cantilever under “normal” loading conditions can be profoundly influenced by the friction between the tip and the surface. It is shown here that a remarkably quantifiable hysteresis occurs in the slope of loading curves whenever the normal flexural stiffness of the AFM cantilever is greater than that of the sample. This situation arises naturally in cantilever-on-cantilever calibration, but also when trying to measure the stiffness of nanomechanical devices or test structures, or when probing any type of surface or structure that is much more compliant ...
Microstructural Characteristics Of Functionally Graded Materials Designed As Dental Post, 2010 Department of Conservative Dentistry, Faculty of Dentistry, University of Thamar, Thamar, Yemen
Microstructural Characteristics Of Functionally Graded Materials Designed As Dental Post, Ahmed A. Madfa
Ahmed A. Madfa
To study the interfaces and microstructure of multilayered materials fabricated based on functionally graded concept for use as dental posts.
Two-Dimensional Fast Surface Imaging Using A Handheld Optical Device: In Vitro And In Vivo Fluorescence Studies, 2010 Department of Biomedical Engineering, Florida International University
Two-Dimensional Fast Surface Imaging Using A Handheld Optical Device: In Vitro And In Vivo Fluorescence Studies, Sarah J. Erickson, Jiajia Ge, Andrea Sanchez, Anuradha Godavarty
Department of Biomedical Engineering Faculty Publications
Near-infrared (NIR) optical imaging is a noninvasive and nonionizing modality that is emerging as a diagnostic tool for breast cancer. The handheld optical devices developed to date using the NIR technology are predominantly developed for spectroscopic applications. A novel handheld probe–based optical imaging device has been recently developed toward area imaging and tomography applications. The three-dimensional (3D) tomographic imaging capabilities of the device have been demonstrated from previous fluorescence studies on tissue phantoms. In the current work, fluorescence imaging studies are performed on tissue phantoms, in vitro, and in vivo tissue models to demonstrate the fast two-dimensional (2D) surface ...
An Investigation Of Humeral Stress Fractures In Racing Thoroughbreds Using A 3d Finite Element Model In Conjunction With A Bone Remodeling Algorithm, 2010 California Polytechnic State University, San Luis Obispo
An Investigation Of Humeral Stress Fractures In Racing Thoroughbreds Using A 3d Finite Element Model In Conjunction With A Bone Remodeling Algorithm, Ryan James Moore
The humerus of a racing horse Thoroughbred is highly susceptible to stress fractures at a characteristic location as a result of cyclic loading. The propensity of a Thoroughbred to exhibit humeral fracture has made equines useful models in the epidemiology of stress fractures. In this study, a racing Thoroughbred humerus was simulated during training using a 3D finite element model in conjunction with a bone remodeling algorithm. Nine muscle forces and two contact forces were applied to the 3-dimensional finite element model, which contains four separate load cases representing fore-stance, mid-stance, aft-stance, and standing. Four different training programs were incorporated ...
Time-Efficient Patient-Specific Quantification Of Regional Carotid Artery Fluid Dynamics And Spatial Correlation With Plaque Burden, John F. Ladisa, Mark Bowers, Leanne Harmann, Robert W. Prost, Anil Vamsi Doppalapudi, Tayyab Mohyuddin, Osama Zaidat, Raymond Q. Migrino
Biomedical Engineering Faculty Research and Publications
Low wall shear stress (WSS) and high oscillatory shear index (OSI) influence plaque formation, yet little is known about their role in progression/regression of established plaques because of lack of practical means to calculate them in individual patients. Our aim was to use computational fluid dynamics(CFD) models of patients with carotid plaque undergoing statin treatment to calculate WSS and OSI in a time-efficient manner, and determine their relationship to plaque thickness (PT), plaque composition (PC), and regression.
Eight patients (68±9 yr, one female) underwent multicontrast 3 T MRI at baseline and six-month post statin treatment ...
Surface Engineering Of Macrophages With Nanoparticles To Generate A Cell-Nanoparticle Hybrid Vehicle For Hypoxia-Targeted Drug Delivery, 2010 Missouri University of Science and Technology
Surface Engineering Of Macrophages With Nanoparticles To Generate A Cell-Nanoparticle Hybrid Vehicle For Hypoxia-Targeted Drug Delivery, Christopher A. Holden, Quan Yuan, W. Andrew Yeudall, Deborah A. Lebman, Hu Yang
Chemical and Biochemical Engineering Faculty Research & Creative Works
Tumors frequently contain hypoxic regions that result from a shortage of oxygen due to poorly organized tumor vasculature. Cancer cells in these areas are resistant to radiation- and chemotherapy, limiting the treatment efficacy. Macrophages have inherent hypoxia-targeting ability and hold great advantages for targeted delivery of anticancer therapeutics to cancer cells in hypoxic areas. However, most anticancer drugs cannot be directly loaded into macrophages because of their toxicity. In this work, we designed a novel drug delivery vehicle by hybridizing macrophages with nanoparticles through cell surface modification. Nanoparticles immobilized on the cell surface provide numerous new sites for anticancer drug ...
Stiffness Of Vascular Smooth Muscle Cells From Aged Primates Measured Using Reconstituted Tissue Model, 2010 New Jersey Institute of Technology
Stiffness Of Vascular Smooth Muscle Cells From Aged Primates Measured Using Reconstituted Tissue Model, Shilpa Nagendra
Increased stiffness of the aorta is an important detrimental change that occurs with aging. Most previous research has implicated stiffening of the extracellular collagen matrix with age. The study reported in this thesis focused instead on the potential contribution from stiffening of the vascular smooth muscle cells (VSMCs) with age.
VSMCs previously obtained from young and old monkeys (macaca fascicularis) were seeded into a collagen gel to form a reconstituted tissue. The aim of this study was to quantitatively characterize the mechanical properties of this reconstituted tissue model via uniaxially stretching each ring to defined levels of strain. The total ...
Development Of A Device For Whole Body Stimulation Of The Otoliths, 2010 New Jersey Institute of Technology
Development Of A Device For Whole Body Stimulation Of The Otoliths, Jon Edward Weimer
Over the past few decades, research has been conducted to explore the effects of microgravity on human musculature, As seen in astronauts upon their return to Earth after prolonged spaceflight, extensive muscle atrophy due to adaptation to conditions of microgravity many times decreases a person's ability to walk or even stand, With an understanding of the anatomical mechanisms that provide postural control, the proper stimulation, resulting in a reduction in spasticity, could be provided by simulating these conditions of microgravity.
In order to simulate microgravity, a device has been developed that is capable of providing whole body stimulation of ...