Biomedical Engineering and Bioengineering Commons^™

High-Level Expression Of A Heterologous Protein In The Milk Of Transgenic Swine Using The Cdna Encoding Human Protein C, William H. Velander, John L. Johnson, Raymond L. Page, Christopher G. Russell, Anuradha Subramanian, Tracy D. Wilkins, Francis C. Gwazdauskas, Christoph Pittius, William N. Drohan

William H. Velander Publications

Transgenic pigs were generated that produced human protein C in their milk at up to 1 g/liter. The gene construct was a fusion gene consisting of the cDNA for human protein C inserted into the first exon of the mouse whey acidic protein gene. These results demonstrate that the mouse whey acidic protein gene contains regulatory elements that can direct cDNA expression at high levels in the pig mammary gland. Recombinant human protein C that was produced at about 380 pg/ml per hr in transgenic pig milk possessed anticoagulant activity that was equivalent to that of protein C derived from …

Viscosities Of Vegetable Oils And Fatty Acids, Hossein Noureddini, B C. Teoh, L Davis Clements

Papers in Biomaterials

Data for viscosity as a function of temperature from 24 to llO°C (75 to 230°F) have been measured for a number of vegetable oils (crambe, rapeseed, corn, soybean, milk- coconut, lesquerella) and eight fatty acids in the from Cg to CZZ The viscosity measurements were performed according to ASTM test methods D 445 and D 446. Several correlations were fitted to the experimental data. Correlation constants for the best fit are presented. The range of temperature in which the correlations are valid is from 24'C (75'F), or the melting point of the substance, to llO°C (230°F). The correlation constants are …

Densities Of Vegetable Oils And Fatty Acids, Hossein Noureddini, B C. Teoh, L Davis Clements

Papers in Biomaterials

Complete data for density as a function of temperature have been measured for a number of vegetable oils (cramhe, rapeseed, corn, soybean, milkweed, coconut, lesquerella), as well as eight fatty acids in the range CS to C,, at temperatures from above their melting points to llQ°C (23Q°F). The specific gravity and density measure mente were performed according to American Society for Testing and Materials (ASTM) standard test methods D 368, D 891 and D 1298 for hydrometers and a modified ASTM D 369 and D 891 for pycnometers. Correlation constants, based on the experimental data, are presented for calculating the …

Sediment Delivery On Rill And Interrill Areas, John E. Gilley, D. C. Kincaid, W. J. Elliot, J. M. Laflen

Biological Systems Engineering: Papers and Publications

Equations which relate sediment delivery to a power function of flow rate and slope gradient were calculated in this study. The data used to parameterize the calculations were obtained from sites where crop residues had been removed. and moldboard plowing and disking had occurred. Measurements of sediment delivery resulting from simulated rainfall were obtained from preformed rills and interrill areas. The equations provided reliable sediment delivery estimates for selected soils located throughout the United States. To use the sediment delivery equations, soil-related parameter values must be identified. Multiple regression analyses were performed to relate parameter values used in the equations …

Oxidative Mechanisms In Arterial Distension Injury: Observations Relevant To Restenosis After Angioplasty, Charles F. Babbs, Yuan Zhong

Weldon School of Biomedical Engineering Faculty Working Papers

Background: To explore the hypothesis that tissue iron and reactive oxygen species, including superoxide (O2), mediate acute inflammatory and late hyperplastic responses to vascular injury, we studied experimental overdistension of normal carotid and femoral arteries in dogs. Experimental design: Arterial segments isolated in situ were distended with Ringer solution at 2 atmospheres pressure. In initial experiments the arteries were excised immediately after distension and immersed in diaminobenzidine solutions containing Mn++ ions to initiate histochemical reactions for O2. In other experiments distended arterial segments were reperfused with arterial blood in the presence or absence of the iron chelator, deferoxamine, or the …

Simulated Crystalline Structures Of Aromatic Polyimides, Tze Wing Poon, B. David Silverman, Ravi F. Saraf, Angelo R. Rossi, Paul S. Ho

Ravi Saraf Publications

Semicrystalline structures involving molecular packing and optimized chain conformations of three polyimides have been obtained with the CHARMM moleculardynamics program, and their densities calculated. An eclipsed conformation of face-toface stacking of polymer chains with a relative shift is observed, and the shift is found to depend upon the molecular characteristics of the planar unit and chain linearity. Threedimensional structures obtained by calculating the optimized edge-on confirmation of the stacked units yield the smallest calculated density for PMDA-ODA, namely 1.515 g/cm³, followed by BPDA-PDA with 1.644 g/cm³ and PMDA-PDA with 1.712 g/cm³. Both PMDA-ODA and BPDA-PDA …

Quantitative Assessment Of Myocardial Oxygen Supply And Demand Using A Dynamic Model Of The Cardiovascular System, Badrinath R. Puranic

Theses

A quantitative understanding of the changes in coronary, pulmonary and systemic hemodynamic variables and their effect on myocardial supply and demand is important to the better management of anesthetic care of patients with impaired cardiac function. Animal studies have identified those hemodynamic factors that play an important role in determining the balance between oxygen supply and demand for the myocardium. These include myocardial contractility, left ventricular end-diastolic volume, systemic arterial pressure, systemic vascular resistance, and heart rate. The interactions of these factors are complex and their combined effects on myocardial oxygen supply and demand are difficult to predict a priori. …

Posterior Stabilized Knee Design Biomechanical Considerations, Donald E. Mcnulty

Theses

Numerous posterior stabilized knee systems are available for primary and revision total knee arthroplasty. Design of these systems requires an understanding of the articulating geometries and kinematic/kinetic biomechanical considerations of the normal knee. The findings for the normal knee are integrated into the design of a prosthetic system.

The natural femoral, tibial and patella articulating geometries are defined to enable subsequent kinematic and kinetic analyses. The articulating geometries are characterized from review of anthropometric studies of the tibiofemoral and patellofemoral joint.

The kinematic analysis of the natural knee defines knee motion in terms of rotation, adduction/abduction, range of motion and …

Mathematical Model And Simulation Of The Progression Of Cutaneous T-Cell Lymphoma, Maria L. Agostinho

Theses

A simple mathematical model and simulation of the progression of cancer with particular emphasis on Cutaneous T Cell Lymphoma was investigated. The mathematical model consists of a set of differential equations that first satisfies the homeostasis levels of the different components present and second predicts the dynamics during a diseased or unhealthy condition. The simulation was done using a FORTRAN program for integrating the differential equations.

Simulation of the immune system is important in evaluating the usefulness of particular sorts of biologically targeted therapies and in selecting the most promising treatment strategies for clinical trials. In particular, the effects of …

The Acoustic Properties Of Human Femoral Bone, Mark Lacianca

Theses

Over the last decade, interest has grown in the use of the scanning acoustic microscope (SAM), with a single lens being used for both transmitting and receiving the acoustic signal. A major objective of this thesis was to determine if the transmission and ultrasonic techniques yield similar "quantitative" results, when measuring the elastic constants of human femoral bone. The transmission technique has been used since 1970 to yield values for the elastic properties of calcified tissue. Previously the SAM has been used as a qualitative tool, where an acoustic impedance map is produced. This map can show areas of bone …

Structural Characterization Of Fucoidan And Its Role In The Hemizona Assay, Manish S. Patankar

Chemistry & Biochemistry Theses & Dissertations

Fucoidan is a polysaccharide commonly found in brown algae. It is a sulfated polymer of the monosaccharide L-fucose. Fucoidan is thought to function in water retention by algae. Commercially available fucoidan is extracted from a brown algae called Eurus vesiculosus.

This polysaccharide has immense potential as a biologically active agent: (i) it exhibits anticoagulant action, (ii) it has also been reported to block retroviral replication and (iii) it is capable of blocking sperm-egg binding in sea urchin, mouse and rabbit. Recently, fucoidan has also been shown to block the interaction of human sperm and egg in the hemizona assay …

Retention Of Cellular Viability And Growth Potential In Cryopreserved Bovine Arterial Tissue: Implications For Clinical Use Of Cryopreserved Vascular Allografts, Kip G. Gardner

Biological Sciences Theses & Dissertations

Segments of bovine calf aortas and pulmonary arteries were cryopreserved at -196° C for two weeks to 18 months and subsequently thawed. Cellular morphology, viability, and growth potential in these segments were then compared with the same attributes in segments from fresh (control) arteries. Scanning electron microscopy revealed no disruption of intimal surfaces attributable to cryopreservation. Endothelial cells were successfully cultured from all cryopreserved arterial segments. Endothelial monolayers grown from cryopreserved arteries had a cobblestone appearance and expressed Factor VIII antigen but not smooth muscle alpha-actin. Plating efficiency in primary cultures of endothelial cells was lower for cryopreserved arteries than …

Beginning Of Motion For Selected Unanchored Residue Materials, John E. Gilley, Eugene R. Kottwitz

Biological Systems Engineering: Papers and Publications

Conservation tillage systems help to maintain residue materials from the previous crop on the soil surface. The potential for serious erosion may exist if crop residues are removed by overland flow. This study is conducted to identify the hydraulic conditions required to initiate residue movement by overland flow. Corn, cotton, peanut, pine needles, sorghum, sunflower, and wheat residue are placed in a flume on smooth and sand surfaces, and flow is then introduced in progressive increments. The discharge rate and flow velocity required to initiate residue movement are identified. Hydraulic measurements are used to calculate the ratio of critical flow …

Evidence That Free Fatty Acid-Iron Complexes Directly Initiate Lipid Peroxidation In Vitro And In Vivo: A New Mechanism Of Oxidative Stress, Steven C. Salaris, Charles F. Babbs, Joann Pham, John J. Turek

Weldon School of Biomedical Engineering Faculty Working Papers

Through a series of biochemical and histochemical experiments we explored the novel hypothesis that iron and free fatty acids, liberated after tissue injury, combine to form liposoluble complexes that directly initiate lipid peroxidation. The addition of 100 M ferric iron to 30 mM linoleate suspensions at pH 7.4 produced time dependent lipid peroxidation, measured as conjugated diene formation. Complexes of 100 M ferric iron and 600 M pentanoate also initiated formation of conjugated dienes in linoleate suspensions and formation of malondialdehyde-like materials in rat liver slices. A histochemical stain for free fatty acids revealed positive reactions within cell membranes in …

New In Vivo And In Vitro Techniques For Quantification Of Lateral Force Levels That Cause Implants To Fail : A Progress Report On Monkey Research, V. Leroy Leggitt

Loma Linda University Electronic Theses, Dissertations & Projects

Two new techniques for quantification of forces generated by an expansion screw apparatus placed between pairs of cylindrical endosseous titanium implants are described, along with preliminary data gained from their use in Macaca rhesus monkeys. Strain gages were bonded to the expansion apparatus and were calibrated either directly by micro load cell, or indirectly by Instron Machine to reflect the applied force.

Immediate loads of up to 6 kilograms have been applied to the implants with no increase in mobility as verified by a Periotest device. No previous studies on the orthodontic uses of implants have evaluated in vivo forces …

Wear And Friction Of Titanium Nitride On Ultra High Molecular Weight Polyethylene Under Oscillating Motion For Evaluation Of Use In Articulating Orthopedic Applications, David Scott Jacobson

Theses

Materials are a factor in the performance of articulating orthopedic implants. An oscillating tribometer is utilized to investigate mechanisms of wear and friction of TiN (titanium nitride) coated on Ti-6Al-4V (titanium) alloy against UHMWPe (ultra high molecular weight polyethylene). Three thicknesses of TiN coating (1.76 pm, 4.15 µm, and 10.5 µm) are used to evaluate the performance of each in UHMWPe wear reduction and coating integrity. An uncoated Co-Cr (cobalt chromium) coupon is used against UHMWPe pins for control purposes. Oscillations are carried out to 10 million cycles to discover and evaluate short- and long-term wear mechanisms. Mass differentials and …

Ultrasonic Ranging System For Gait Analysis, Mu Wu

Theses

A new method of measuring range for gait analysis is described. The method is based on a coherent measurement of the phase shift of an ultrasonic signal as a function of range.

A prototype of the ranging system was breadboarded, tested, and found to have a relative accuracy of better than 0.5 mm over a range of 3 meters. The maximum range the system is at least 20 meters. The method used here is new and has not been found in the literature. Tt is demonstrated by experiments with a prototype system that can measure distance with a higher accuracy …

Effect Of 2,3-Butanedione Monoxide On Whole-Cell Potassium Channel Currents In Rat Single Myocytes, Youliang Zhou

Theses

The patch clamp technique is a simple procedure which can isolate ion channels on cell membranes. Our previous data have shown that 2,3-Butanedione Monoxime (BDM) could inhibit the calcium current by dephosphorylation of the channel. In this study, the effect of BDM on the potassium channels were investigated with the whole-cell recording method in single myocytes enzymatically isolated from the left ventricle of 3-4 months old rats. Superfusion of myocytes with BDM elicited a dose dependent decrease of the outward transient potassium current. BDM with concentrations of 5, 20 and 50 mM reduced the maximal peak potassium current by 7.3 …

The Effects Of Twist On Pressure Through A Teflon Vascular Prosthesis, Steven Alfred Olivieri

Theses

A closed loop fluid system was developed which mimics the flow curve in the human circulatory system in order to test the effects of pressure drop and flow velocity on artificial arterial implants. This device consists of a piston pump connected to a microcomputer controlled servo-motor. Fluid (in this case distilled water) flows through transparent Tygon tubing to a test chamber. The prosthetic tube is placed in the fluid but is attached through a specially constructed chamber. The pressure across the implant can be measured for different conditions. System compliance was generated by using flexible tubing in the return loop …

A Computer Implementation Of A Multi-Neuron Expandable Network, Mary Ellen Ellen Aleksza

Theses

The primary goal of this thesis is to develop a small, expandable neural network that oscillates when presented with an appropriate stimulus. This model will be used in the future as a base to create larger networks. Future studies of these larger networks may be used in the simulation of neuronal activity such biological oscillators.

This thesis encompasses a study of neuron activity, neural networks, neuron models and biological oscillators. The focus of the thesis is the modification and expansion of a single neuron simulation into a simulation of an interconnected multi-neuron oscillatory network.

A single neuron model based on …

Slow, Red-Green Counterphase (Parvo) And Fast, Black-White Magno) Snow In The Detection Of Scotomata In Primary Open-Angle Glaucoma, Rey Favis

Theses

No one knows why Primary Open Angle Glaucoma sufferers can detect their glaucoma induced blindspots by monocularly fixating on a mark in the center of a screen of television snow. An attempt was made to determine which of two pathways from retina to lateral geniculate nucleus is more involved in the detection of the blindspots. Previous studies demonstrated that the large diameter axon, magno cellular pathway is maximally stimulated by 30 Hertz high contrast black-white patterns. The small diameter axon, parvo cellular pathway is known from past research to be maximally stimulated by 12 Hertz red-green counterphase patterns. It was …

Comparison Of Optimization Methodologies For Sustained-Yield Groundwater Pumping Planning In East Shore Area, Utah, Shu Takahashi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Combined simulation and optimization models, which are helpful for long-term groundwater planning of complex nonlinear aquifer systems, are developed using alternative modelling approaches. The models incorporate a representation of steady-state, quasi-three-dimensional head response to pumping within an optimization. An embedding model which describes exactly the nonlinear flow of an unconfined aquifer is presented. In contrast with the embedding models presented in the Utah State University Ground Water Model, it directly achieves the optimal solution without a "cycling." To address the nonlinearity of the flow system, response matrix models couple superposition with the cycling procedure. Their linear influence coefficients are generated …

Network Analysis Of Intermediary Metabolism Using Linear Optimization. Ii. Interpretation Of Hybridoma Cell Metabolism, Joanne M. Savinell (Belovich), Bernhard O. Palsson

Chemical & Biomedical Engineering Faculty Publications

Analysis of metabolic networks using linear optimization theory allows one to quantify and understand the limitations imposed on the cell by its metabolic stoichiometry, and to understand how the flux through each pathway influences the overall behavior of metabolism. A stoichiometric matrix accounting for the major pathways involved in energy and mass transformations in the cell was used in our analysis. The auxiliary parameters of linear optimization, the so-called shadow prices, identify the intermediates and cofactors that cause the growth to be limited on each nutrient. This formalism was used to examine how well the cell balances its needs for …

Darcy-Weisbach Roughness Coefficients For Gravel And Cobble Surfaces, John E. Gilley, Eugene R. Kottwitz, Gary A. Wieman

Biological Systems Engineering: Papers and Publications

A laboratory study is conducted to measure Darcy-Weisbach roughness coefficients for selected gravel and cobble materials. Varying rates of flow are introduced into a flume in which a given size class of gravel or cobble material is securely attached. Roughness coefficients are calculated from measurements of discharge rate and flow velocity. The laboratory data are used to develop regression equations for relating roughness coefficients to surface cover and Reynolds number. The regression relations, which are developed for values of the Reynolds number from approximately 500 to 16,000, are tested using hydraulic data collected on surfaces containing a distribution of size …

Effects Of Hurricane Hugo On Agricultural Structures, Jay D. Harmon, George F. Grandle, Clyde L. Barth

Jay D. Harmon

A tour of damage to agricultural structures by hurricane Hugo was conducted. Empty grain bins which exhibited improper anchorage tended to fail. Post-frame buildings that were improperly anchored, braced or fastened failed, while others that were designed and constructed using sound engineering practices generally withstood hurricane winds.

Interaction Of Liposomal Drug Delivery Systems With Cells And Tissues: Microscopic Studies, M. Foldvari, G. T. Faulkner, C. Mezei, M. Mezei

Cells and Materials

Liposomes , as drug carriers, can be administered into the body by several routes e.g. intravenously, intraperitoneally, intramuscularly, intratracheally and topically among others. Radiolabelled markers are suitable to monitor the distribution and elimination of liposomes, but the tissue deposition of intact liposomes, the mode and sites of drug release from the liposomes and liposome-cell interactions cannot be investigated morphologically. Microscopic techniques could provide information regarding the intact state of liposomes and possibly the dynamics of liposomes in tissues provided that they can be identified with certainty in vivo. This is a formidable problem and in spite of several attempts, there …

Microstructure Of Mica Glass-Ceramics And Interface Reactions Between Mica Glass-Ceramics And Bone, W. Holand, W. Gotz, G. Carl, W. Vogel

Cells and Materials

This review paper characterizes glass-ceramics containing mica as main crystal phase. The phase formation reactions in dependence of the chemical composition and the microstructure are shown. Microstructure of mica glass-ceramics has been studied by electron replica and scanning electron microscopic (SEM) techniques.

Mica glass-ceramics have previously been developed in Si02-B20rA120rMgO-F--base glasses. The material is machinable because of the precipitation of micas of fluorophlogopite-type. Also, a machinable glass-ceramic for dental applications was developed based on KMg2_5(Si40 10)F2-micas. We developed mica glass-ceramics in the Si02-Al20rMgO-NaiO-K20-F glass system. Phase formation within these glasses was observed by SEM. A double controlled nucleation and crystallization …

The Effect Of Polymethylmethacrylate Bone Cement Vibration On The Bone-Cement Interface, A. M. C. Thomas, D. J. W. Mcminn, M. Haddaway, I. W. Mccall

Cells and Materials

Low frequency vibration of polymethylmethacrylate (PMMA) bone cement reduces the viscosity of the cement by shear thinning. The effect of this low frequency vibration on the bone-cement interface was studied using microfocal radiography (MFR) and scanning electron microscopy (SEM). Effects were studied in-vitro and in-vivo. In-vitro, samples of Palacos low viscosity PMMA were placed on blocks of Kiel bone and vibrated. MFR and SEM demonstrated an improvement in the appearance of the bone-cement interface. In-vivo, PMMA was injected into the upper tibia of the dog. An assessment of the effect of high and low pressure injection, and the effect of …

Ultrastructural Assessment Of Lesion Development In The Collared Rabbit Carotid Artery Model, J. E. Beesley, A. C. Honey, J. F. Martin

Cells and Materials

Cellular reactions associated with the formation of lesions generated in the carotid artery of rabbits fed either normal or high cholesterol diets by the placement of a flexible, silastic collar around the artery, were studied by electron microscopy.

Endothelial cells remained as a monolayer throughout lesion development. The endothelial cell surface in both experimental and sham operated carotids, 4 hours and 8 hours after the initiation of the experiments, were covered with platelets and leukocytes. Neutrophils were present until 7 days in the arteries from within the collar of animals maintained on a normal diet, but only to 1 day …

Applications Of Fourier Transform Infrared (Ft-Ir) Microscopy To The Study Of Mineralization In Bone And Cartilage, Adele L. Boskey, Nancy Pleshko, Stephen B. Doty, Richard Mendelsohn

Cells and Materials

Knowledge of the phase, composition, and crystallite size and perfection of the mineral in normal and abnormally calcified tissues provides insight into the mechanism by which this mineral was deposited. These data also can be used to develop rational therapies for pathological conditions characterized by abnormal mineral deposition. As illustrated in this review, coupling of an optical microscope with a Fourier transform infrared (FT-IR) spectrophotometer permits the mapping at 20 μm spatial resolution of changes in mineral characteristics (content, particle size, composition) in the growth plate, in bone biopsies, in mineralizing cell culture systems, and in soft tissue calcifications. Based …