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Full-Text Articles in Analytical, Diagnostic and Therapeutic Techniques and Equipment

Preosteoblast Behavior On A Synthetic Calcium Phosphate Scaffold Coated With Cell Derived Matrix, Daniel A. Young May 2010

Preosteoblast Behavior On A Synthetic Calcium Phosphate Scaffold Coated With Cell Derived Matrix, Daniel A. Young

Theses and Dissertations (ETD)

Bone grafts are commonly used for the treatment of large bone defects. Biodegradable, synthetic bone grafts combined with cells and growth factors as a tissue engineered construct can provide benefits over the common autografts and allografts currently used. Calcium phosphate (CaP) materials offer high biocompatibility and chemical similarity to natural bone tissue. Biodegradable beta-tricalcium phosphate (β-TCP) scaffolds with an interconnected porous network have been created to promote tissue ingrowth and regeneration in vitro and in vivo. Extracellular matrix (ECM) coated on titanium and polymer scaffolds has been shown to improve cell response to those material surfaces. Here, we attempted …


Chitosan/Ellagic Acid Composite Materials For Local Cancer Therapy, Sung Woo Kim Dec 2009

Chitosan/Ellagic Acid Composite Materials For Local Cancer Therapy, Sung Woo Kim

Theses and Dissertations (ETD)

Current advances in the drug delivery have improved the therapeutic efficacy of the drug and minimized risks of side effects associated with toxicity of the drug. Implantable polymeric delivery system has gained increasing attentions for controlled drug release and localized treatments. In comparison to conventional chemotherapy, polymeric delivery systems are implantable at a local targeted site and biodegradable after a sufficient therapeutic span. The objectives of this project were to fabricate and characterize an implantable polymeric vehicle for a local chemotherapy and investigate its biological properties against cancer cells including human WM115 melanoma, human U87 glioblastoma, and rat C6 glioma …


Spatial Resolution Analysis Of A Variable Resolution X-Ray Cone-Beam Computed Tomography System, Bahram Dahi May 2009

Spatial Resolution Analysis Of A Variable Resolution X-Ray Cone-Beam Computed Tomography System, Bahram Dahi

Theses and Dissertations (ETD)

A new cone-beam computed tomography (CBCT) system is designed and implemented that can adaptively provide high resolution CT images for objects of different sizes. The new system, called Variable Resolution X-ray Cone-beam CT (VRX-CBCT) uses a CsI-based amorphous silicon flat panel detector (FPD) that can tilt about its horizontal (u) axis and vertical (v) axis independently. The detector angulation improves the spatial resolution of the CT images by changing the effective size of each detector cell. Two components of spatial resolution of the system, namely the transverse and axial modulation transfer functions (MTF), are analyzed in …


Feasibility Study Of Liquid-Based Cytology For Post-Treatment Surveillance Of Patients With Vulvar Intraepithelial Neoplasia, Wendy Likes May 2009

Feasibility Study Of Liquid-Based Cytology For Post-Treatment Surveillance Of Patients With Vulvar Intraepithelial Neoplasia, Wendy Likes

Theses and Dissertations (ETD)

Introduction: Colposcopy and tissue biopsy remain the gold standard for diagnosing vulvar intraepithelial neoplasia (VIN). Vulvar colposcopy is fairly nonspecific. As a result, many women undergo unwarranted painful biopsies. Vulvar cytology, which is relatively painless, inexpensive and allows a larger area to be sampled, may likely reduce false negative diagnoses. However, previous cytological studies that used conventional methodologies were largely unsuccessful in diagnosing VIN. In this study, liquid based cytology and HPV typing by PCR have been assessed as possible alternatives to biopsy for follow-up surveillance of women treated for VIN.

Methods: Women with a history of VIN and a …


The Use Of Spectroscopic Techniques In The Characterization Of Mycobacterial Metabolites, Engy Abdelhameed Mahrous May 2009

The Use Of Spectroscopic Techniques In The Characterization Of Mycobacterial Metabolites, Engy Abdelhameed Mahrous

Theses and Dissertations (ETD)

The mycobacterial cell wall metabolites have always imposed great challenges to researchers due to their unusual complexity and structural diversity. A lot of research efforts have been directed towards the evaluation of these metabolites and the role they play in the pathogenesis and virulence of different serious human pathogens including Mycobacterium tuberculosis the causative agent of tuberculosis (TB). In the genomic era, it is crucial to develop new methodologies to analyze these components from a global perspective in a comprehensive and well-validated manner.

Towards this end, we developed a rapid NMR-based approach to produce metabolic profiles in the form of …


Diffusion Tensor Imaging In Pediatric Brain Tumor Patients, Nicholas S. Phillips May 2009

Diffusion Tensor Imaging In Pediatric Brain Tumor Patients, Nicholas S. Phillips

Theses and Dissertations (ETD)

In this dissertation, we outline our efforts to introduce an advanced MRI imaging technique called Diffusion Tensor Imaging (DTI) to the pediatric brain tumor population. We discuss the theory and application of DTI as it was performed in a series of translational investigations at St. Jude Children’s Research Hospital. We present evidence of how the introduction of this technique impacted diagnosis, and treatment. And finally, we demonstrate how DTI was used to investigate cognitive morbidities associated with cancer treatment and how this research provided insight into the underlying pathophysiology involved in the development of these treatment sequela.

This research has …


Biomechanical Comparison Of Lumbar Disc Replacements, Peter Wong May 2009

Biomechanical Comparison Of Lumbar Disc Replacements, Peter Wong

Theses and Dissertations (ETD)

Surgical options for lumbar spinal disorders are rapidly expanding. One seemingly promising area is the lumbar disc replacement. Design specifications vary among the manufacturers based upon differing perceptions of ideal motion. Comparison studies are important in quantifying different features for future improvements but are currently lacking. The objective of this study was to compare the biomechanical properties of three currently available treatments: disc replacement with ProDisc-L, disc replacement with Maverick, and a pedicle screw fixation. It was hypothesized that structural designs differences of ProDisc-L and Maverick could be distinguished in both motion and loading patterns. It was also hypothesized that …


The Role Of Inflammation In The Early Radiation Response, Christy Marie Wilson May 2009

The Role Of Inflammation In The Early Radiation Response, Christy Marie Wilson

Theses and Dissertations (ETD)

Radiation is one of the principal treatments for adults and children with brain tumors, and is one of the oldest established treatments for tumors of all types. Currently, the limiting factor for the use of radiation is the effect on normal tissue adjacent to the tumor. Toxicity, including early and late effects from radiation, limits the dose administered to the tumor and reduces the probability of cure. This work has three aims in its attempt to understand and limit early radiation damage: characterize the role of the inflammatory molecules tumor necrosis factor alpha (TNF) and intracellular adhesion molecule-1 (ICAM-1) in …


The Combined Effect Of In-Situ Tumor And Irradiation On Peritumoral Brain Vasculature, Janice Ann Zawaski May 2009

The Combined Effect Of In-Situ Tumor And Irradiation On Peritumoral Brain Vasculature, Janice Ann Zawaski

Theses and Dissertations (ETD)

In the USA, 200,000 brain tumors are diagnosed each year with glioma representing 8.4% of the 200,000. The standard treatment for glioma consists of surgical resection, when possible, followed by radiation therapy (RT) and/or chemotherapy. Radiation therapy is one of the most effective treatments of brain tumors; however, the therapeutic ratio of RT is limited by damage to the normal tissue. We hypothesize that tumor growth has an adverse effect on the peritumoral tissue through the angiogenic/inflammatory environment it creates rendering it susceptible to further damage by RT which may be prevented by using anti-angiogenic/anti-inflammatory agents. We have developed a …


Kinematic Demands Of Nucleus Arthroplasty Technology, Elizabeth J. Sander Dec 2008

Kinematic Demands Of Nucleus Arthroplasty Technology, Elizabeth J. Sander

Theses and Dissertations (ETD)

Recent advancements in biomaterial technologies have fostered growth in alternative surgical procedures to fusion surgery for treatment of early stages of degenerative disc disease. One application of immediate interest is that of nucleus arthroplasty (NA). Novel materials are being developed to better match the nonlinear biomechanical properties of the native tissue. The effects of changing the motion segment unit (MSU) properties via surgery (nucleotomy) or placement of a nucleus arthroplasty material, changes the effort or work required to move the altered spine condition through a prescribed kinematic path relative to the intact spine condition. The closer the loading mechanics of …


Use Of Compliant Interbody Force Sensing Grafts To Compare Load Sharing Properties Of Unidirectional And Bidirectional Multilevel Dynamic Translational Anterior Cervical Plates, Jason Roscoe Roberson Dec 2008

Use Of Compliant Interbody Force Sensing Grafts To Compare Load Sharing Properties Of Unidirectional And Bidirectional Multilevel Dynamic Translational Anterior Cervical Plates, Jason Roscoe Roberson

Theses and Dissertations (ETD)

INTRODUCTION: Pseudoarthrosis is a relatively rare complication following anterior cervical arthrodesis, and is felt to be related to stress shielding. To address this, dynamic anterior cervical plates have emerged to maintain load sharing as an arthodesis matures. Dynamic plates can translate bidirectionally (allow translation in compressive and tensile loads), or unidirectionally (allow translation in compression, but maintain its position under tensile loads). The objective of this study was to compare the graft load mechanics between three plated conditions during settling using compliant interbody load cells: A static (fixed, non-moving) plate, a unidirectional multi-level translational plate design, and a bidirectional two-level …


A Kinematics-Based Testing Protocol To Study The Mechanics Of The Human Lumbar Spine, Nephi A. Zufelt Dec 2008

A Kinematics-Based Testing Protocol To Study The Mechanics Of The Human Lumbar Spine, Nephi A. Zufelt

Theses and Dissertations (ETD)

The objective of this work was to develop a new kinematics-based testing protocol to quantify the axial and shear force components and rotational moment properties of the human cadaveric lumbar motion segment unit (MSU) in response to specific kinematic inputs. Modern, non-fusion spinal devices claim to treat degenerative disc disease better than traditional fusion surgery. Though there have been many biomechanical studies completed on these devices, there is still a debate over their efficacy. Conventional testing methods provide insight into the rotational properties of the MSU but lack the sensitivity or capacity to quantify lumbar MSU’s mechanical properties including shear …


Theoretical And Experimental Evaluation Of Spatial Resolution In A Variable Resolution X-Ray Computed Tomography Scanner, Roman Melnyk Dec 2007

Theoretical And Experimental Evaluation Of Spatial Resolution In A Variable Resolution X-Ray Computed Tomography Scanner, Roman Melnyk

Theses and Dissertations (ETD)

A variable resolution x-ray (VRX) computed tomography (CT) scanner can image objects of various sizes with greatly improved spatial resolution. The scanner employs an angulated discrete detector and achieves the resolution boost by matching the detector angulation to the scanner field of view (FOV) determined by the size of an object being imaged. A comprehensive evaluation of spatial resolution in an experimental version of the VRX CT scanner is presented in this dissertation. Two components of this resolution were evaluated – the pre-reconstruction spatial resolution, described by the detector presampling modulation transfer function (MTF), and the post-reconstruction spatial resolution, given …


Depth And Size Limits For The Visibility Of Veins Using The Veinviewer Imaging System, Soujanya Ganesh May 2007

Depth And Size Limits For The Visibility Of Veins Using The Veinviewer Imaging System, Soujanya Ganesh

Theses and Dissertations (ETD)

Administration of fluids or medication and blood draw procedures require the nurse or the phlebotomist to access the veins in patients at hospitals or phlebotomy centers. It is important to minimize the discomfort associated with sticking needles in the patient more than once and most often, necessary to find an appropriate vein within few minutes. However, problems involved in accessing veins in pediatric and obese patients make it very difficult to perform a successful stick in a short time. The VeinViewer Imaging System is an infrared imaging device that provides the nurses and phlebotomists a means for locating veins in …


Biomechanical Testing Of Two-Level Cervical Disc Arthroplasty, Laura J. Gilmour Dec 2006

Biomechanical Testing Of Two-Level Cervical Disc Arthroplasty, Laura J. Gilmour

Theses and Dissertations (ETD)

In vitro biomechanical studies comparing two-level cervical disc arthroplasty with two-level fusion were completed using an established cadaveric cervical spine model. Three conditions were tested: non-instrumented, instrumented with two-level fusion (C5-C6 and C6-C7), and instrumented with two-level arthroplasty (C5-C6, C6-C7) using the Prestige Low-Profile (Medtronic Sofamor Danek, Memphis TN) or ProDisc-C (Synthes Spine, West Chester PA) prosthetic disc. Specimens were tested non-destructively in physiologic flexion-extension, lateral bending, and axial rotation to an end-limit load of 3-Nm or 45o rotation. Rotations at the superior, implanted, and inferior motion segment units (MSU) of the instrumented conditions were normalized to the non-instrumented condition …


A Computer Simulation Model Of The Human Head-Neck Musculoskeletal System, Jun Yan Dec 2006

A Computer Simulation Model Of The Human Head-Neck Musculoskeletal System, Jun Yan

Theses and Dissertations (ETD)

Objective. The objective of this research was to develop a muscle-driven biomechanical model of the human head-neck system that could be used to simulate neck movements under muscle control. This model can further be modified to enable input from an external stimulus, such as EMG data.

Summary of background data. Utilizing computer aided design (CAD) and dynamic simulation software programs, the Joint Implant Biomechanics Laboratory at The University of Tennessee Health Science Center developed a virtual model of the human cervical spine to simulate the in vitro biomechanical experiments. This in vitro model did not include any muscle …


Mapping Of Cortical Motor Reorganization In Spinal Cord Injury, Leonid Rozhkov Dec 2001

Mapping Of Cortical Motor Reorganization In Spinal Cord Injury, Leonid Rozhkov

Theses and Dissertations (ETD)

The annual incidence of spinal cord injury (SCI), not including those who die at the scene of the accident, is approximately 10,000 new cases in the United States. SCI, in its best outcome, may partially and temporarily disconnect the spinal cord from the brain. Some neuronal pathways remain intact in most S CI individuals, whose recovery depends on the utilization of the surviving connections. There is a change in the control of voluntary movements of the extremities by the cerebral cortex of the brain following spinal cord injury.

The technology of high-resolution EEG co-registered with MRI was applied to non-invasively …


Qualitative Evaluation Of Data Compression In Real-Time Ultrasound Imaging, Bijoy J. Sundersingh Jun 2000

Qualitative Evaluation Of Data Compression In Real-Time Ultrasound Imaging, Bijoy J. Sundersingh

Theses and Dissertations (ETD)

The purpose of this project was to evaluate qualitatively real-time ultrasound imaging using objective and subjective techniques to determine the minimum bandwidth required for clinical diagnosis of various anatomical and pathological states. In the experimental setup live ultrasound video samples representing the most common clinical examinations were compressed at 128, 256, 384, 768, 1152 and 1536 kbps using a compressor-decompressor (CODEC) adhering to International Telecommunication Union (ITU-T) recommendation H.261. A protocol for qualitative evaluation was developed and subjective and objective testing were performed based on this protocol. Subjective methods comprised of inter-rater reliability tests using kappa statistics and three way …


Functional Significance Of The Upregulation Of Adhesion Molecules On Irradiated Endothelial Cells, Balabhaskar Prabhakarpandian Jun 2000

Functional Significance Of The Upregulation Of Adhesion Molecules On Irradiated Endothelial Cells, Balabhaskar Prabhakarpandian

Theses and Dissertations (ETD)

Ionizing radiation is a major therapy for cancer. Damage to the endothelium and upregulation of inflammatory responses are major side effects of radiotherapy, but the mechanisms behind these processes are not clear. A key component of the inflammatory response is leukocytes adhesion to the endothelium in a multi-step process involving leukocyte tethering to the endothelium, followed by rolling, firm adhesion/spreading and extravasation. Adhesion molecules mediate this process, particularly, E-selectin and ICAM-1, which are inducible adhesion molecules. E-selectin is involved in the initial tethering and rolling steps of the adhesion cascade while ICAM-1 appears to be involved in the latter steps. …


Portal Imaging Using A Csi (Tl) Scintillator Coupled To A Cooled Ccd Camera, Amit Sawant Nov 1999

Portal Imaging Using A Csi (Tl) Scintillator Coupled To A Cooled Ccd Camera, Amit Sawant

Theses and Dissertations (ETD)

The purpose of this research was to design a high performance digital portal imaging
system, using a transparent x-ray scintillator coupled to a cooled CCD camera. Theoretical
analysis using Monte Carlo simulation was performed to calculate the QDE, SNR and DQE of
the system. A prototype electronic portal imaging device (EPID) was built, using a 12.7 mm
thick, 20.32 cm diameter, CsI (Tl) scintillator, coupled to an Astromed ® liquid nitrogen cooled
CCD TV camera. The system geometry of the prototype EPID was optimized to achieve high
spatial resolution. Experimental evaluation of the prototype EPID was performed, by
determining its …


Late Effects Of Ionizing Radiation On Normal Microvascular Networks, Vinh Nguyen Jun 1999

Late Effects Of Ionizing Radiation On Normal Microvascular Networks, Vinh Nguyen

Theses and Dissertations (ETD)

Therapeutic doses of ionizing radiation result in changes in the structure and function of microvascular networks in normal tissue. Previously, we reported on the early effects of ionizing radiation on microvascular networks at 3, 7, and 30 days post-irradiation [1-3]. Data from the early time points suggested that ionizing radiation significantly alters the structure and function of microvascular networks and interferes with the normal processes of vessel maturation. Here, we
present our findings on the late effects of ionizing radiation on normal tissue microvasculature at 60, 120, and 180 days post-irradiation. The cremaster muscle of Golden Syrian hamster was locally …


Job Accommodation In The Automobile Industry : Addressing The Problem Of Lateral Epicondylitis, Thanigaivel Ashwin Raj Jan 1996

Job Accommodation In The Automobile Industry : Addressing The Problem Of Lateral Epicondylitis, Thanigaivel Ashwin Raj

Theses and Dissertations (ETD)

Cumulative trauma disorders are musculoskeletal problems such as carpal tunnel syndrome, rotator cuff tendinitis, and epicondylitis which can affect assembly line workers. The injuries are thought to result from repetitive motions performed under excessive loads in anomalous postures. The project aimed to design, build, install, and evaluate worksite accommodation at the Saturn plant for a worker with right lateral epicondylitis. The goal was to make her fully functional in her original team which required addressing the injurious aspects of the task that caused or aggravated her injury.

A process of observation, interview, and analysis identified “the door mount” operation on …


Characteristics Of The Recovery Of The Coenzyme A-Synthesizing Protein Complex From Saccharomyces Cerevisiae, Stanley Joseph Tarnowski Jr. Dec 1979

Characteristics Of The Recovery Of The Coenzyme A-Synthesizing Protein Complex From Saccharomyces Cerevisiae, Stanley Joseph Tarnowski Jr.

Theses and Dissertations (ETD)

A multienzyme complex contained in Bakers' yeast (Saccharomyces cerevisiae) which synthesizes CoA has been named the coenzyme A-synthesizing protein complex (CoA-SPC). The CoA-SPC has been shown to be insoluble in the crude Bakers' yeast cell lysate formed by exposing the yeast cell to ether and dry ice. Only after solubilization has this multienzyme complex been shown to catalyze the formation of bound dephospho-CoA utilizing the substrates adenosine triphosphate, D-pantothenic acid and L-cysteine. A low molecular weight component or components of the soluble fraction of the yeast cell and chloride ion appears to be responsible for the solubilization of CoA-SPC. This …


The Purification, Properties And Subunit Structure Of Glycerol Dehydrogenase, Michael James Barrett Dec 1969

The Purification, Properties And Subunit Structure Of Glycerol Dehydrogenase, Michael James Barrett

Theses and Dissertations (ETD)

The inducible, NAD-linked glycerol dehydrogenase (E.C. 1.1.1.6) of a guanine requiring mutant of A. aerogenes has been purified to homogeneity. The molecular weight of the pure enzyme was found to be 3.4 x 105 daltons. The sedimentation coefficient of the enzyme was 10.7 x 10-13 sec.-1. The diffusion constant was 3.07 x 10-7 cm2/sec.

The partial specific volume calculated from the amino acid composition was 0.72 ml/g. The following kinetic parameters were determined; Km glycerol, 2.4 x 10-3 m, Km NAD, 2.8 x 10-4 M, Km dihydroxyacetone, 5.1 …


Root Surface Area Related To Anchorage In The Begg Technique, Donald Copeland Freeman Jun 1965

Root Surface Area Related To Anchorage In The Begg Technique, Donald Copeland Freeman

Theses and Dissertations (ETD)

Almost two hundred years ago Hunter recognized the necessity of extracting teeth to ’’procure room for the others which are to be brought into the arch.” He further noted that, ”To extract an irregular tooth would answer but little purpose if no alteration could be made in the situation of the rest.”1

Extraction of selected teeth to gain room for the proper placement of the rest, and the subsequent procedures to utilize this space to the utmost advantage, have been integral parts of orthodontic treatment for many years.

Strang and Thompson2 stated that the ability to manipulate any …