Biomedical Engineering and Bioengineering Commons^™

Why Is Ca3 More Vulnerable Than Ca1 In Experimental Models Of Controlled Cortical Impact-Induced Brain Injury?, Haojie Mao, Benjamin S. Elkin, Vinay V. Genthikatti, Barclay Morrison Iii, King H. Yang

Biomedical Engineering Faculty Research Publications

One interesting finding of controlled cortical impact (CCI) experiments is that the CA3 region of the hippocampus, which is positioned further from the impact than the CA1 region, is reported as being more injured. The current literature has suggested a positive correlation between brain tissue stretch and neuronal cell loss. However, it is counterintuitive to assume that CA3 is stretched more during CCI injury. Recent mechanical studies of the brain have reported on a level of spatial heterogeneity not previously appreciated—the finding that CA1 was significantly stiffer than all other regions tested and that CA3 was one of the most …

How Atomic Level Interactions Drive Membrane Fusion: Insights From Molecular Dynamics Simulations, Navendu Bhatnagar

Wayne State University Dissertations

This project is focused on identifying the role of key players in the membrane fusion process at the atomic level with the use of molecular dynamics simulations. Membrane fusion of apposed bilayers is one of the most fundamental and frequently occurring biological phenomena in living organisms. It is an essential step in several cellular processes such as neuronal exocytosis, sperm fusion with oocytes and intracellular fusion of organelles to name a few. Membrane fusion is a frequent process in a living organism but is still not fully understood at the atomic level in terms of the role of various factors …

Cervical Spine Tolerance And Response In Compressive Loading Modes Including Combined Compression And Lateral Bending, Daniel Toomey

Wayne State University Dissertations

Injuries in motor vehicle accidents continue to be a serious and costly societal problem. Automotive safety researchers have observed noticeable lateral bending of the anthropomorphic test device (ATD) neck prior to or in conjunction with head impact with the vehicle roof in rollover crash tests. Since there is scant data available about the effects of lateral bending on overall compressive tolerance of the human cervical spine, it is unknown if the presence of lateral bending is important to consider during impacts with the apex of the head. Compressive injury tolerance has historically been reported by identifying the axial force at …

Use Of Focused Ultrasound For Transcranial Sonothrombolysis, Golnaz Ahadi

Wayne State University Dissertations

Worldwide, stroke is the second most common cause of death. Ischemic stroke remains accountable for the majority of the 20 million devastating stroke events occurring globally each year. Use of transcranial focused ultrasound (FUS) for sonothrombolysis is a new research field for ischemic stroke treatment. If shown to be effective, FUS sonothrombolysis could become a widely available treatment option for the majority of the stroke sufferers that do not qualify or do not have access to current thrombolytic treatment options, such as tPA or neurointerventional methods.

The current study was an in vitro transcranial FUS headsystem investigation for the potential …

Imaging Iron Content In Patients With Multiple Sclerosis Using Magnetic Resonance Imaging, Charbel Abdo Habib

Wayne State University Dissertations

The importance of iron in maintaining normal physiological processes in the human body has been well emphasized in the literature. However, "when iron behaves badly", its abnormal presence might lead to a spectrum of pathologies depending on what function has been altered. In the brain, for instance, abnormal iron content is thought to be associated with neurodegenerative diseases. In this dissertation, we study iron involvement in one of the most debilitating neurological diseases, multiple sclerosis (MS), using in vivo magnetic resonance imaging. We first test the sensitivity and specificity of the MR method used, known as susceptibility weighted imaging (SWI) …

Investigation Of Physiochemical Properties Of A Novel Gradient Calcium Polyphosphate Bone Scaffold And Its Influence On Cellular Behavior, Liang Chen

Wayne State University Theses

A good designed bone scaffold is crucial to bone tissue engineering. We have developed and characterized a novel gradient bone scaffold by combination of Calcium Polyphosphate (CPP) with different size of porogen (stearic acids). Compared with homogenous scaffold, the gradient bone scaffold with different pore size and porosity can better mimic natural bone structure. Directly perfusion flow bioreactor was developed. This 3D dynamic cell culture was better mimic the physiological condition for cell growth. It was beneficial to nutrition and oxygen delivery throughout the whole scaffold and was able to form shear stress. We wanted to investigate the effect of …

The Role Of Tissue Sound Speed As A Surrogate Marker Of Breast Density, Mark Sak

Wayne State University Dissertations

Breast density is one of the strongest predictors of breast cancer risk as women with the densest breasts have a three- to five-fold increase in risk compared to women with the least dense breasts. Breast density is currently measured by using mammography, the current gold standard for breast imaging. There are many shortcomings to using mammography to measure breast density, including the use of ionizing radiation. Ultrasound tomography (UST) does not use ionizing radiation and can create tomographic breast sound speed images. These sound speed images are useful because breast density is proportional to sound speed. The purpose of this …

Hyperglycemia Induces Differential Change In Oxidative Stress At Gene Expression And Functional Levels In Huvec And Hmvec, Hemang Patel, Juan Chen, Kumuda C. Das, Mahendra Kavdia

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Endothelial dysfunction precedes pathogenesis of vascular complications in diabetes. In recent years, the mechanisms of endothelial dysfunction were investigated to outline strategies for its treatment. However, the therapies for dysfunctional endothelium resulted in multiple clinical trial failures and remain elusive. There is a need for defining hyperglycemia-induced endothelial dysfunction with both generic and specific dysfunctional changes in endothelial cells (EC) using a systems approach. In this study, we investigated hyperglycemia-induced endothelial dysfunction in HUVEC and HMVEC. We investigated hyperglycemia-induced functional changes (superoxide (O₂‾), and hydrogen peroxide (H₂O₂) production and mitochondrial membrane polarization) …

Synthesis And Characterization Of Biodegradable Poly(Vinyl Esters) With Hdac Inhibitory Activity, Kyle Lawrence Horton

Wayne State University Theses

HDAC inhibitors are known to have anti-inflammatory properties. HDAC inhibitors are used in combination with Oct4 to generate induced pluripotent stem cells. I hypothesized that polyesters based on simple aliphatic HDAC inhibitors like valproic acid (VPA) and phenylbutyric acid (PBA) can serve as alternatives to existing polyester biomaterials with improved anti-inflammatory properties and as scaffolds for generation of iPSCs when used in combination with layer-by-layer thin films delivering reprogramming transcription factors. Vinyl ester of phenylbutyric acid (VEPA) and vinyl ester of valproic acid (VEVA) were synthesized from their carboxylic acid precursors using an iridium complex catalyst at yields as high …

Compressed Sensing And Joint Acquisition Techniques In Mri, Rouhollah Hamtaei

Wayne State University Theses

The relatively long scan times in Magnetic Resonance Imaging (MRI) limits some clinical applications and the ability to collect more information in a reasonable period of time. Practically, 3D imaging requires longer acquisitions which can lead to a reduction in image quality due to motion artifacts, patient discomfort, increased costs to the healthcare system and loss of profit to the imaging center. The emphasis in reducing scan time has been to a large degree through using limited k-space data acquisition and special reconstruction techniques. Among these approaches are data extrapolation methods such as "constrained reconstruction" techniques, data interpolation methods such …

Induced Damping And Its Relationship To Beneficial Energy Harvesting In Dielectric Elastomers With Application To Walking, Heather L. Lai

Wayne State University Dissertations

This dissertation presents a novel, interdisciplinary research which addresses the potential of applying soft polymeric materials to strategically harvest biomechanical energy in a beneficial manner for use as a viable, low power source for on-board electronics. Of particular interest are electroactive polymers (EAP), which unlike other types of electromechanical smart materials such as piezoelectric ceramics, which are often brittle, have low elastic modulus and can exhibit large strains without substantial stress generations. One type of EAP, the dielectric elastomer (DE), which utilizes electrostatic forces built up across the dielectric polymer to convert between electrical and mechanical energy, is employed in …

Visual Exploration And Information Analytics Of High-Dimensional Medical Images, Darshan Pai

Wayne State University Dissertations

Data visualization has transformed how we analyze increasingly large and complex data sets. Advanced visual tools logically represent data in a way that communicates the most important information inherent within it and culminate the analysis with an insightful conclusion. Automated analysis disciplines - such as data mining, machine learning, and statistics - have traditionally been the most dominant fields for data analysis. It has been complemented with a near-ubiquitous adoption of specialized hardware and software environments that handle the storage, retrieval, and pre- and postprocessing of digital data. The addition of interactive visualization tools allows an active human participant in …

Studying The Glial Cell Response To Biomaterials And Surface Topography For Improving The Neural Electrode Interface, Evon S. Ereifej

Wayne State University Dissertations

Neural electrode devices hold great promise to help people with the restoration of lost functions, however, research is lacking in the biomaterial design of a stable, long-term device. Current devices lack long term functionality, most have been found unable to record neural activity within weeks after implantation due to the development of glial scar tissue (Polikov et al., 2006; Zhong and Bellamkonda, 2008). The long-term effect of chronically implanted electrodes is the formation of a glial scar made up of reactive astrocytes and the matrix proteins they generate (Polikov et al., 2005; Seil and Webster, 2008). Scarring is initiated when …

Raman Spectroscopy And Diffuse Reflectance Spectroscopy For Diagnosis Of Human Cancer And Acanthosis Nigricans, Suneetha Devpura

Wayne State University Dissertations

Cancer and diabetes are common chronic diseases in today's world causing numerous deaths in adults as well as children. Most common types of cancers in adults include prostate, lung, breast, colorectal and head and neck squamous cell carcinoma, while among children; leukemia, and brain and central nervous system cancers are quite common. In each of these cases, early detection of the cancer or disease dramatically increases the chances of successful treatment. In recent years, there has been much interest in using Raman spectroscopy and diffuse reflectance spectroscopy as analytical optical spectroscopic methods for early diagnosis of diseases. Raman spectroscopy can …

Numerical Simulation And Experimentation Of Pulsatile Flows In Axisymmetric Arterial Models, Tadesse Gebreegziabher

Wayne State University Dissertations

ABSTRACT

NUMERICAL SIMULATION AND EXPERIMENTATION OF PULSATILE FLOWS IN AXISYMMETRIC ARTERIAL MODELS

by

TADESSE GEBREEGZIABHER

December 2011

Co-advisors: 1. Dr. Emmanuel Ayorinde 2. Dr. Trilochan Singh

Major: Mechanical Engineering

Degree: Doctor of Philosophy

The primary motivation for this dissertation is the fluid flow and structural response to unsteady blood flow in the human body. The research work is a synergistic merging of numerical simulation and experimentation. For the experiments, an all-encompassing, highly flexible experimental apparatus was designed and fabricated to facilitate a wide range of operating conditions, the range of which was chosen to accommodate mammalian cardiovascular system for both …

Biomechanical Stability Of A Supra-Acetabular Pedicle Screw Internal Fixation Device (Infix) Vs External Fixation And Plates For Vertically Unstable Pelvic Fractures, Jonathan M. Vigdorchik, Amanda O. Esquivel, Xin Jin, King H. Yang, Ndidi A. Onwudiwe, Rahul Vaidya

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

We have recently developed a subcutaneous anterior pelvic fixation technique (INFIX). This internal fixator permits patients to sit, roll over in bed and lie on their sides without the cumbersome external appliances or their complications. The purpose of this study was to evaluate the biomechanical stability of this novel supraacetabular pedicle screw internal fixation construct (INFIX) and compare it to standard internal fixation and external fixation techniques in a single stance pelvic fracture model.

Methods

Nine synthetic pelves with a simulated anterior posterior compression type III injury were placed into three groups (External Fixator, INFIX and Internal Fixation). …

Football Helmet Fitment And Its Effect On Helmet Performance, Ron Jadischke

Wayne State University Theses

A method and system to objectively quantify helmet fitment was designed and developed. It measures the pressure between the energy-absorbing material in the helmet and the athlete's head. This system is also capable of measuring surface pressure during impact events. A volunteer-based field study was conducted to quantify how helmets were fitting athletes in a real-life setting. The helmets fit athletes in varying degrees of tightness and evenness. Most athletes (59%) had the highest pressures in the frontal area and 29% had the highest pressure in the occipital area. A large-sized helmet on the Hybrid III headform represented how most …

Contact Pressure Distribution Of Osteochondral Defects Of The Knee: Effects Of Non-Vertical Walls, Scott Ensminger

Wayne State University Theses

Purpose: To examine the relationship between well-shouldered osteochondral defects and

defects of different geometries by studying their effects on rim stress concentration and

load redistribution in the human knee.

Methods: Ten fresh-frozen cadaveric knees were mounted at 30° of flexion in a materials

testing machine. Digital electronic pressure sensors were placed in the medial and lateral

compartments of the knee. Dynamic pressure readings were recorded throughout the

loading and holding phases as each knee was loaded to 700N and held for 5 seconds.

Artificial defects were created in each knee to simulate well-shouldered defects and

beveled-defects. Loading was repeated for …

Traumatic Brain Injury Induced Cerebral Blood Flow Changes - A Potential Role For Caffeine, Sharath Chandra Reddy Bandaru

Wayne State University Theses

Traumatic brain injury (TBI) is a global health problem with significant socio-economic costs. Closed head TBIs are one of the major causes of physical disability and cognitive disorder in young adults and a leading cause of death in children.

Alteration in cerebral blood flow due to an impaired autoregulation is one of the most common consequences of TBI. However, studies related to understanding the temporal changes in CBF following TBI in experimental models are limited. The few available studies report acute reduction in CBF following TBI; knowledge related to CBF changes at sub-acute periods extending to 7 days after TBI …

Neurophysiological Changes In Spinal Nerve Roots Subjected To Tensile Loading At Several Strain Rates, Gurjiwan Singh Virk

Wayne State University Theses

ABSTRACT:

Spinal nerve roots have been implicated in many types of traumatic injuries such as motor vehicle accidents, falls, and sports injury, causing damage to brachial plexus and lumbosacral plexus. They have also been involved in lower back pain, disc herniation or protrusions, sciatica, and traumatic birth delivers such as shoulder dystocia. These roots undergo tension, resulting in traumatic axonal injury (TAI), which is also one of the consequences of traumatic brain injury (TBI). Every year about 2 million cases of TBI are reported nationwide with variable neurological deficits. Thus, it is important to understand the neurophysiological response and injury …

Techniques For Sensor-Integrated Robotic Systems: Raman Spectra Analysis, Image Guidance, And Kinematic Calibration, Luke Anthony Reisner

Wayne State University Dissertations

Robotics and sensor technology have made impressive advancements over the years. There are now robotic systems that help perform surgeries or explore the surface of Mars, and there are sensors that detect trace amounts of explosives or identify diseased human tissue. The most powerful systems integrate robots and sensors, which are natural complements to each other. Sensors can provide information that might otherwise be unavailable due to indirect robotic manipulation (e.g., images of the target environment), and robots can provide suitably precise positioning of an analytical sensor.

To have an effective sensor-integrated robotic system, multiple capabilities are needed in the …

Enhancing The Mechanical Properties Of A Hydroxyapatite-Collagen Bone Surrogate, Richard Franz Banglmaier

Wayne State University Dissertations

The synthesis of biomimetic hydroxyapatite-collagen composites is desirable from the perspective of graft elimination and load-bearing support when treating damaged or diseased bone. Bone is an organized network of carbonated hydroxyapatite mineralized collagen, whose strength and toughness is dependent on the organized array of mineralized collagen fibers that align with applied physiologic stresses. The apatitic calcium phosphate phase, hydroxyapatite, is promising for the biomimetic mineralization of collagen. Hydroxyapatite-collagen composites are osteoconductive and resorbable. However, the mechanical properties of these composites are one or more orders of magnitude less than bone. The aim of this study was to produce a bone-like …

High-Frequency Ultrasound For Intraoperative Margin Assessments In Breast Conservation Surgery: A Feasibility Study, Timothy E. Doyle, Rachel E. Factor, Christina L. Ellefson, Kristina M. Sorensen, Brady J. Ambrose, Jeffrey B. Goodrich, Vern P. Hart, Scott C. Jensen, Hemang Patel, Leigh A. Neumayer

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

In addition to breast imaging, ultrasound offers the potential for characterizing and distinguishing between benign and malignant breast tissues due to their different microstructures and material properties. The aim of this study was to determine if high-frequency ultrasound (20-80 MHz) can provide pathology sensitive measurements for the ex vivo detection of cancer in margins during breast conservation surgery.

Methods

Ultrasonic tests were performed on resected margins and other tissues obtained from 17 patients, resulting in 34 specimens that were classified into 15 pathology categories. Pulse-echo and through-transmission measurements were acquired from a total of 57 sites on the …

Reinforced Chitosan-Based Heart Valve Scaffold And Utility Of Bone Marrow-Derived Mesenchymal Stem Cells For Cardiovascular Tissue Engineering, Mohammad Z. Albanna

Wayne State University Dissertations

Recent research has demonstrated a strong correlation between the differentiation profile of mesenchymal stem cells (MSCs) and scaffold stiffness. Chitosan is being widely studied for tissue engineering applications due to its biocompatibility and biodegradability. However, its use in load-bearing applications is limited due to moderate to low mechanical properties. In this study, we investigated the effectiveness of a fiber reinforcement method for enhancing the mechanical properties of chitosan scaffolds. Chitosan fibers were fabricated using a solution extrusion and neutralization method and incorporated into porous chitosan scaffolds. The effects of different fiber/scaffold mass ratios, fiber mechanical properties and fiber lengths on …

An Investigation Of The Biomechanical Response From Shock Wave Loading To The Head, Alessandra Dal Cengio Leonardi

Wayne State University Dissertations

There is a pressing need for a comprehensive explanation of the mechanism of brain injury after exposure to blast and several hypotheses have been suggested. The focus of this research was to investigate one of the hypotheses for primary brain injury due to blast: multimodal skull flexure. The significance of this research is twofold. First, resolution of the mode of energy transfer and of the induced stresses within the skull-brain system will allow for creations of mitigation/protective techniques/equipment, as well as design of experiments investigating live-cell response using more reliable physical models. Second, the data obtained experimentally will be available …

Finite Element Reconstruction Of Real World Aortic Injury In Near-Side Lateral Automotive Crashes With Conceptual Countermeasures, Aditya Neelakanta Belwadi

Wayne State University Dissertations

Traumatic rupture of the aorta (TRA) remains the second most common cause of death associated with motor vehicle crashes after brain injury. On an average, nearly 8,000 people die annually in the United States due to blunt injury to the aorta. It is observed that more than 80% of occupants who suffer an aortic injury die at the scene due to exsanguination into the chest. With the advent of more accurate and established human body finite element (FE) models, FE crash reconstruction methods may become a valuable tool when assessing crash scenarios and occupant injury mechanisms.

The current study is …

Differences Between Adult And Pediatric Neck Muscle Stress Due Muscle Recruitment Patterns, Renee Dawson

Wayne State University Dissertations

In 2000 and 2001 an estimated 150,000 children between the ages of 0 and 8 years old were injured or killed in a motor vehicle accident. Despite advances in child safety restraints and vehicle restraints, automobile accidents remain the primary cause of death for children in the 0-8 year old age group. In 1982, in an attempt to reduce the number of deaths and injuries of children, the first child crash test dummy was developed. The responses of this dummy were scaled from the adult response data based on the assumption that children were similar to adults both anatomically and …

Comparison Of Progression Of Diffuse Axonal Injury With Histology And Diffusion Tensor Imaging, Nisrine Zakaria

Wayne State University Dissertations

Diffuse axonal injury, also known as traumatic axonal injury (TAI), is a major contributor to the pathology of traumatic brain injury. However, TAI is undetectable to conventional clinical magnetic resonance (MR) imaging techniques. Histologically, TAI is characterized by swollen axons that eventually disconnect and form axonal retraction balls (RB) in various white matter tracts. MR-diffusion tensor imaging (MR-DTI) has been reported to be sensitive to TAI in human TBI patients by measuring water molecular diffusion motion in white matter fiber tracts. To date, only one correlative animal study has been carried out to investigate the DTI relationship to TAI, and …

Development Of A Biomechanical Surrogate For The Evaluation Of Commotio Cordis Protection, Nathan Dau

Wayne State University Dissertations

Commotio Cordis (CC) has proven to be life threatening for young athletes as it is the second leading cause of mortality in youth sports. In the past 15 years, researchers have been working to understand the pathophysiology of this event. It has been proven that impacts directly over the cardiac silhouette during a vulnerable period of the cardiac cycle can cause CC. In order to reduce the occurrence of CC in sports, chest protectors need to be tested for efficacy. Currently there is no biofidelic surrogate to serve this purpose. In order to test equipment to a given standard of …

A Multi-Species Analysis Of Biomechanical Responses Of The Head To A Shock Wave, Richard Bolander

Wayne State University Dissertations

Shock wave induced brain injury remains a field of research that has great consequences for the rehabilitation of soldiers and civilians that are exposed to an explosion. As such, for the research to be successful in developing strategies to mitigate the effects of these injuries, appropriate research methods need to be developed. Animal models are currently employed to understand the brain's response to a shock wave exposure. Unfortunately no criteria have been established that indicates in what way the mechanical inputs that the cells in an animal's brain are subjected to are similar to a human. The purpose of this …