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Wayne State University

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Articles 1 - 30 of 82

Full-Text Articles in Biomedical Engineering and Bioengineering

Mechanical Interventions In Soft Tissue Repair, Elizabeth Marie Meier Jan 2017

Mechanical Interventions In Soft Tissue Repair, Elizabeth Marie Meier

Wayne State University Dissertations

This body of work sets to investigate some of these mechanical interventions that are designed to promote wound healing, repair, or even replace an injured tissue. By investigating three separate tissues and three separate mechanical interventions, we can draw conclusions about the implications of including mechanical interventions in biomedical research and clinical treatments. The use of sutures to close wounds is highly common, however the effects of sutures on the tensile mechanics of human skin are largely unknown. To evaluate how sutures may affect uniaxial tensile mechanics, human skin samples were sutured and loaded in tension in multiple orientations. The ...


Development Of A Programmed Electrospun Three Dimensional (3d) Nanofiber Collecter And It’S Application To Orthopedic Implant Coatings, Liang Chen Jan 2017

Development Of A Programmed Electrospun Three Dimensional (3d) Nanofiber Collecter And It’S Application To Orthopedic Implant Coatings, Liang Chen

Wayne State University Dissertations

Orthopedic implants might not directly unite with bones especially in compromised patients even if they have been appropriately fixed. The lack of early osseointegration would lead to the failure of the orthopedic implant. A “bone-like” implant surface is urgently needed to accelerate osseointegration. Electrospun nanofiber (NF) is a promising implant coating due to its highly porous nanoscale structure. It mimics the collagen I nanofibrous network of bone tissue; meanwhile it has been widely used as a drug delivery device. However, its compact and dense structure is not ideal for cell growth. Our strategy was to develop a functional three-dimensional (3D ...


Biomechanics Of Concussion: The Importance Of Neck Tension, Ron Jadischke Jan 2017

Biomechanics Of Concussion: The Importance Of Neck Tension, Ron Jadischke

Wayne State University Dissertations

Linear and angular velocity and acceleration of the head are typically correlated to concussion. Despite improvements in helmet performance to reduce accelerations, a corresponding reduction in the incidence of concussion has not occurred (National Football League [NFL] 1996 – present).

There is compelling research that forces on and deformation to the brain stem are related to concussion. The brain stem is the center of control for respiration, blood pressure and heart rate and is the root of most cranial nerves. Injury to the brain stem is consistent with most symptoms of concussion reported in the National Football League and the National ...


Design Of A Modular Endothelialized Platform For Vascularized Bone Regeneration, Kevin Barrett Miles Jan 2017

Design Of A Modular Endothelialized Platform For Vascularized Bone Regeneration, Kevin Barrett Miles

Wayne State University Dissertations

The gold standard for bone regeneration requires harvesting a piece of healthy bone from the patient through a painful procedure, but this piece of autologous bone graft contains the bone and endothelial cells required to rapidly regenerate bone in a defect. We have developed a modular bone regeneration platform, composed of mesenchymal stem cells (MSCs) and hydroxyapatite (HAP) microgranules encapsulated in microcapsules, to replace autologous graft harvesting. The microcapsules are composed of a polyelectrolyte membrane formed by the ionic-complex reaction between chondroitin 4-sulfate (C4S) and chitosan. The specific aims of this thesis were to 1) examine the ability of C4S ...


Development Of A Finite Element Pelvis And Lower Extremity Model With Growth Plates For Pediatric Pedestrian Protection, Ming Shen Jan 2017

Development Of A Finite Element Pelvis And Lower Extremity Model With Growth Plates For Pediatric Pedestrian Protection, Ming Shen

Wayne State University Dissertations

Finite element (FE) model is a useful tool frequently used for investigating the injury mechanisms and designing protection countermeasures. At present, no 10 years old (YO) pedestrian FE model has been developed from appropriate anthropometries and validated against limitedly available impact response data. A 10 YO child FE pelvis and lower extremities (PLEX) model was established to fill the gap of lacking such models in this age group. The baseline model was validated against available pediatric postmortem human subjects (PMHS) test data and additional scaled adult data, then the PLEX model was integrated to build a whole-body FE model representing ...


Brain Connectivity After Concussion, Armin Iraji Jan 2017

Brain Connectivity After Concussion, Armin Iraji

Wayne State University Dissertations

Mild traumatic brain injury (mTBI) accounts for over one million emergency visits in the United States each year. While most mTBI patients have normal findings in clinical neuroimaging, alterations in brain structure and functional connectivity have frequently been reported. In this study, we investigated the large-scale brain structural and functional connectivity using diffusion MRI and resting-state fMRI data. Data from 40 mTBI patients was acquired at the acute stage (within 24 hrs after injury). 35 patients returned for data acquisition at a follow-up (4-6 weeks after injury). Data was also collected from a cohort of 58 healthy subjects, 36 of ...


Mri Methods For Imaging The Feto-Placental Vasculature And Blood, Uday Krishnamurthy Jan 2017

Mri Methods For Imaging The Feto-Placental Vasculature And Blood, Uday Krishnamurthy

Wayne State University Dissertations

Fetal magnetic resonance imaging (MRI) in recent times has become a well-established adjunct to ultrasound (US) in routine clinical prenatal care and diagnostics. The majority of fetal MRI is restricted to T2-weighted scans, where the diagnosis is based on the appearance of normal and abnormal tissue. Although there have been many advancements in MRI and a plethora of sequences, that probe different anatomical and different physiological process, the adaptation of these in fetal imaging has been rather slow. Many of these can extract quantitative parameters that can throw light on the underlying tissue’s normal/patho-physiology. But the use of ...


Pet Imaging Of Early Therapeutic Response In Solid Tumors, Stephanie J. Blocker Jan 2017

Pet Imaging Of Early Therapeutic Response In Solid Tumors, Stephanie J. Blocker

Wayne State University Dissertations

An important pillar of precision medicine for oncology is the ability to identify patients who respond to treatment early into their therapy. Positron emission tomography (PET) allows physicians and researchers to measure changes in tumor behavior prior to noticeable differences in morphology.

Objective: Determine the utility of multiple tracers for PET in assessing early changes in tumor activity that result from treatment.

Methods: Two tracers for PET were studied. 64Cu-labeled liposomes were used to assess changes in liposome delivery two solid colon tumors early into treatment with bevacizumab (Bev). 18F-FMAU thymidine analog (1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)thymine), was utilized to ...


Biomaterials Approaches For Utilizing The Regenerative Potential Of The Peripheral Nerve Injury Microenvironment, Melissa Renee Wrobel Jan 2017

Biomaterials Approaches For Utilizing The Regenerative Potential Of The Peripheral Nerve Injury Microenvironment, Melissa Renee Wrobel

Wayne State University Dissertations

Clinically available treatments are insufficient to achieve full functional recovery in large (>3cm) peripheral nerve injuries (PNI). The objectives in this thesis were 1) to study often overlooked elements of intrinsic PNI repair including release of inhibitory CSPGs and post-injury responses of inflammatory macrophages and dedifferentiated Schwann cells; 2) to create biomaterial scaf-folds featuring topographical and adhesive cues to enhance neurite outgrowth; and 3) to test the ability of those cues to direct macrophages and Schwann cells towards a pro-regenerative phe-notype. It is hypothesized that recapitulating the positive and negative cues of the PNI microenvi-ronment can better improve regeneration. The ...


Quantitative Assessment Of Brain Iron Content As A Function Of Age Using Magnetic Resonance Imaging, Kiarash Ghassaban Jan 2016

Quantitative Assessment Of Brain Iron Content As A Function Of Age Using Magnetic Resonance Imaging, Kiarash Ghassaban

Wayne State University Theses

As the most abundant transition metal in the brain, iron is known to play a key role in a variety of functional and cellular processes. Recent in vivo and post-mortem studies have shown that the levels of iron deposition in the brain, particularly in deep gray matter nuclei, vary as a function of age. On the other hand, elevated iron has also been associated with some neurodegenerative diseases such as Multiple Sclerosis (MS) and Parkinson’s disease (PD) among others.

Magnetic Resonance Imaging (MRI) is a widely used non-invasive and non-ionizing imaging modality which is sensitive to magnetic properties of ...


Enhancement Of Cancer Vaccine Efficacy Via Nanoparticle Or Molecular-Based Adjuvants, Myunggi An Jan 2016

Enhancement Of Cancer Vaccine Efficacy Via Nanoparticle Or Molecular-Based Adjuvants, Myunggi An

Wayne State University Theses

Adjuvants are immunomodulators which enhance immune responses to vaccines. However, parenteral administration of unformulated adjuvants fails to reach lymph nodes (LNs), the anatomic organ where the primary functions of immune cells are orchestrated. The LN-targeting delivery plays the key roles in promoting immune activation and has the great potential to transform disease treatment. The main goal of this thesis is to develop efficient vaccine delivery systems to target therapeutics into draining lymph nodes (dLNs) for ensuring their immunostimulatory activity. We introduced therapeutic applications of activating TLR9 with synthetic CpG oligodeoxynucleotide (ODN) agonists in nanoparticle or molecular form to activate immune ...


Europium(Ii)-Containing Complexes For Responsive Magnetic Resonance Imaging, Levi Alexander Ekanger Jan 2016

Europium(Ii)-Containing Complexes For Responsive Magnetic Resonance Imaging, Levi Alexander Ekanger

Wayne State University Dissertations

The research projects described in this dissertation are focused on studying the oxidation of EuII-containing complexes within the context of responsive MRI. Prior to this research, EuII had not been explored within the context of oxidation-responsive MRI nor had the use of this ion been reported in vivo. The results of these studies enable predictions about the oxidation-responsive behavior of EuII-containing complexes in vitro and in vivo.

The EuII-containing cryptate 1.33 was used to evaluate EuII-based positive contrast enhancement after intravenous, intraperitoneal, and subcutaneous injections. The transitory behavior of the positive contrast enhancement correlated with reported levels of oxygenation ...


Dendrimer Nanoconjugates And Their Oral Inhalation Formulations For Lung Cancer Therapy, Qian Zhong Jan 2016

Dendrimer Nanoconjugates And Their Oral Inhalation Formulations For Lung Cancer Therapy, Qian Zhong

Wayne State University Dissertations

Lung cancers are leading cause of cancer death for both men and women in the world. Lungs are also one of the primary organs to which almost all cancer can spread. Chemothepray plays a crucial role in the fight against both primary lung cancers and lung metastases. Doxorubicin (DOX) is a potent anticancer drug that has been approved for treating many cancers including lung cancers. However, only a few percent of systemically administered DOX can be found in the lungs. The issue is further complicated by dose-limiting toxicity of DOX. Another major challenge in the use of DOX is its ...


Sub-Picogram, Inline Detection Of Proteins Using Microfluidic Drop Generators And Shape-Based Detection, Razieh Kebriaei Jan 2016

Sub-Picogram, Inline Detection Of Proteins Using Microfluidic Drop Generators And Shape-Based Detection, Razieh Kebriaei

Wayne State University Dissertations

Proteomic workflows rely on sensitive and precise methods for purifying and detecting proteins, and one of the most popular methods is liquid chromatography (LC) followed by an inline detector. However, the most commonly used method, UV-Vis absorbance, provides relatively low sensitivity and requires long path lengths in the flow cell. In this thesis, we present a highly sensitive, label-free method to detect proteins in continuous flow, using a pressure-driven microfluidic droplet generator. The system consists of a cross junction or flow focusing structure where the flowing stream of proteins is combined with two coflowing streams of oil which break up ...


X-Ray Beam Characteristics And Radiation Dose Deposition To Soft Tissue From Fluoroscopic X-Ray Beams Incorporating Copper Filtration, Kevin Arthur Wunderle Jan 2016

X-Ray Beam Characteristics And Radiation Dose Deposition To Soft Tissue From Fluoroscopic X-Ray Beams Incorporating Copper Filtration, Kevin Arthur Wunderle

Wayne State University Dissertations

Purpose: This work investigated several topics related to dosimetry in soft tissue from fluoroscopic X-ray beams; first, it investigated the X-ray beam spectra and air kerma rates available for clinical use on state-of-the-art fluoroscopes using spectral (copper [Cu]) filtration; second, it investigated the fluoroscopic X-ray beam characteristics of first half-value layer (HVL), second HVL, homogeneity coefficients (HCs), and backscatter factors (BSFs) across the full range of available beam qualities; and third, it investigated the energy dependence of kerma-area-product (KAP)-meters measuring the radiation output of the fluoroscope. Materials and Methods: A state-of-the-art Siemens Artis Zee fluoroscope was operated in the ...


Fe3o4 Nanoparticles For Magnetic Hyperthermia And Drug Delivery: Synthesis, Characterization And Cellular Studies, Maheshika Palihawadana Arachchige Jan 2016

Fe3o4 Nanoparticles For Magnetic Hyperthermia And Drug Delivery: Synthesis, Characterization And Cellular Studies, Maheshika Palihawadana Arachchige

Wayne State University Dissertations

In recent years, magnetic nanoparticles (MNPs), especially superparamagnetic Fe3O4nanoparticles, have attracted a great deal of attention because of their potential applications in biomedicine. Among the other applications, Magnetic hyperthermia (MHT), where localized heating is generated by means of relaxation processes in MNPs when subjected to a radio frequency magnetic field, has a great potential as a non-invasive cancer therapy treatment. Specific absorption rate (SAR), which measures the efficiency of heat generation, depends on magnetic properties of the particles such as saturation magnetization (Ms), magnetic anisotropy (K), particle size distribution, magnetic dipolar interactions, and the rheological properties of the target medium ...


Toward Magnetic Resonance Only Treatment Planning: Distortion Mitigation And Image-Guided Radiation Therapy Validation, Ryan Glen Price Jan 2016

Toward Magnetic Resonance Only Treatment Planning: Distortion Mitigation And Image-Guided Radiation Therapy Validation, Ryan Glen Price

Wayne State University Dissertations

While MR-only treatment planning has shown promise, there are still several well-known challenges that are currently limiting widespread clinical implementation.

Firstly, MR images are affected by both patient-induced and system-level geometric distortions that can significantly degrade treatment planning accuracy. . In addition, the availability of comprehensive distortion analysis software is currently limited. Also while many groups have been working toward a synthetic CT solution, further study is needed on the implementation of synCTs as the reference datasets for linac-based image-guided radiation therapy (IGRT) to help determine their robustness in an MR-only workflow.

A 36×43×2 cm3 phantom with 255 known ...


Oxygen Transport, Shear Stress, And Metabolism In Perfused Hepatocyte-Seeded Scaffolds With Radial Pore Architecture: Experimental And Computational Analyses, Chijioke Mbanu Jan 2016

Oxygen Transport, Shear Stress, And Metabolism In Perfused Hepatocyte-Seeded Scaffolds With Radial Pore Architecture: Experimental And Computational Analyses, Chijioke Mbanu

Wayne State University Dissertations

Several modalities have been proposed as treatments or temporary stop-gap for patients suffering from liver failure until a suitable organ is available. However there is still an urgent need for an off-the-shelf device that can accommodate clinically relevant cell numbers, be cultured at physiological oxygen tensions and, can be fully integrated into and heal the injured hepatic space. In this study we investigated the effects that convective and direct oxygenation had on hepatocyte functionality, morphology and viability while cultured in bulk 3D chitosan scaffolds and perfusion bioreactor systems. Cylindrical chitosan scaffolds with radial directed pore structures were fabricated by a ...


Development Of Carbon Based Neural Interface For Neural Stimulation/Recording And Neurotransmitter Detection, Wenwen Yi Jan 2016

Development Of Carbon Based Neural Interface For Neural Stimulation/Recording And Neurotransmitter Detection, Wenwen Yi

Wayne State University Dissertations

Electrical stimulation and recording of neural cells have been widely used in basic neuroscience studies, neural prostheses, and clinical therapies. Stable neural interfaces that effectively communicate with the nervous system via electrodes are of great significance. Recently, flexible neural interfaces that combine carbon nanotubes (CNTs) and soft polymer substrates have generated tremendous interests. CNT based microelectrode arrays (MEAs) have shown enhanced electrochemical properties compared to commonly used electrode materials such as tungsten, platinum or titanium nitride. On the other hand, the soft polymer substrate can overcome the mechanical mismatch between the traditional rigid electrodes (or silicon shank) and the soft ...


Development Of Novel Radiotracers For Pet Imaging Of Hdac-Mediated Epigenetic Regulation, Robin Edwards Bonomi Jan 2016

Development Of Novel Radiotracers For Pet Imaging Of Hdac-Mediated Epigenetic Regulation, Robin Edwards Bonomi

Wayne State University Dissertations

Over the past two decades, epigenetic regulation has become a rapidly growing, highly innovative and influential field of biology and medicine. Protein acetylation and deacetylation, two key epigenetic regulatory mechanisms, are mediated by histone acetylase transferases (HATs) and histone deacetylases (HDACs), respectively. To date, the vast majority of studies on epigenetic regulation have been conducted in cell cultures and tissue samples using conventional methodologies of molecular and cellular biology, which contain inherent limitations for monitoring therapy and disease. Therefore, there is a growing need for novel, advanced methodologies that allow for non-invasive detection and monitoring of HDAC–mediated epigenetic regulatory ...


Novel Pulsatile Cardiac Assist Pump, Lakshmi Mohanadas Jan 2015

Novel Pulsatile Cardiac Assist Pump, Lakshmi Mohanadas

Wayne State University Theses

The project involve the research and development of a pulsatile, complex or continuous flow in biological and non-biological systems implantable heart assist pump. Specifically as a 20% cardiac assist for persons from congestive heart failure and other cardiac abnormalities. The pulsatile cardiac assist pump would provide upto 20% of the blood pumping process from the venous supply to the arterial supply. Current pumps are largely complete bypass pumps or large volume pumps that produce significant long term blood cell damage resulting in thrombosis. Most are not pulsatile which offers a significant physiological advantage. The pump under development is designed to ...


Assessment Of Temporal And Spatial Alterations In Spinal Glial Reactivityand The Extent Of Cervical Spinal Axonal Injury In The Rat After Blast Overpressure, Heena S. Purkait Jan 2015

Assessment Of Temporal And Spatial Alterations In Spinal Glial Reactivityand The Extent Of Cervical Spinal Axonal Injury In The Rat After Blast Overpressure, Heena S. Purkait

Wayne State University Theses

Blast induced neurotrauma (BINT) is the signature wound of veterans returning from various military operations. A substantial percentage of Operations Enduring Freedom (OEF) and Iraqi Freedom (OIF) veterans have reported to experience ongoing or new pain following their military service. Head (58%) and back (55%) have been the high prevailing locations of pain in these returning OIF and OEF veterans and the underlying pathomechanism of these conditions is yet to be understood. In the context of blast overpressure induced pathological changes, the fundamental question that still needs to be addressed is whether there are any underlying cellular injury changes the ...


Fabrication And Characterization Of A Robust, Field- Deployable, Optical Sensor Designed To Detect Particles In Oils., Navya Pandreka Jan 2015

Fabrication And Characterization Of A Robust, Field- Deployable, Optical Sensor Designed To Detect Particles In Oils., Navya Pandreka

Wayne State University Theses

Some types of bacteria and fungus can use iron or non-ferrous metals for their metabolic process. Sulfate-reducing bacteria can corrode pipes in the oil industry and high-end machinery. Both aerobic and anaerobic bacteria often degrade fuel quality and cause fuel system corrosion or alter the chemical properties of the fluid. This causes significant economic damage and safety concerns. Therefore, there is a need for a system to continuously monitor fuel or lubricant oil for the presence of bacteria and fungus.

The main goal of this project was to develop a sensor that can detect bacteria and other ferrous and non-ferrous ...


Quantitative Brain Electrical Activity In The Initial Screening Of Mild Traumatic Brain Injuries After Blast, Chengpeng Zhou Jan 2015

Quantitative Brain Electrical Activity In The Initial Screening Of Mild Traumatic Brain Injuries After Blast, Chengpeng Zhou

Wayne State University Theses

ABSTRACT

QUANTITATIVE BRAIN ELECTRICAL ACTIVITY IN THE INITIAL SCREENING OF MILD TRAUMATIC BRAIN INJURIES AFTER BLAST

by

CHENGPENG ZHOU

August 2015

Advisor: Dr. John Michael Cavanaugh, Dr. Chaoyang Chen

Major: Biomedical Engineering

Degree: Master of Science

Objective: Quantitative electroencephalography (QEEG) has been reported to be sensitive in the diagnosis and measurement of mild traumatic brain injury (mTBI) in civilian setting and thus may be a promising tool in individuals who have been exposed to blast forces. Using a swine model, this study investigated EEG changes early after blast exposure. The purpose was to determine if QEEG can detect brain activity ...


Programmable Dna Delivery To Cells Using Bioreducible Layer-By-Layer (Lbl) Polyelectrolyte Thin Films, Maria Muniz Jan 2015

Programmable Dna Delivery To Cells Using Bioreducible Layer-By-Layer (Lbl) Polyelectrolyte Thin Films, Maria Muniz

Wayne State University Theses

Bioreducible, layer-by-layer (LbL) polyelectrolyte films show great promise for use in biomedical implant and gene-delivery applications. These nanometer-scale thin films can easily be coated onto a variety of implantable surfaces or devices. To achieve proof of concept, HEK-293, NIH/3T3, RAW, and MC3T3 cells were transfected using plasmid DNA with the green fluorescent protein reporter gene (GFP-DNA). In order to optimize transfection, a number of polyelectrolytes and biological components were systematically incorporated into the two similar basic LbL structures. Based on our previous degradation assays, it is shown that cellular interactions in vitro can break down the layers of the ...


Evaluation Of Mems Fabricated Fractal Based Free Standing Scaffolds For The Purposes Of Developing A Brain Bioreactor, Brandy Broadbent Jan 2015

Evaluation Of Mems Fabricated Fractal Based Free Standing Scaffolds For The Purposes Of Developing A Brain Bioreactor, Brandy Broadbent

Wayne State University Theses

The brain is the most complex organ in the body due to the multiple cell types,

billions of tightly packed synapses, extracellular matrix, and intricate topography. Microelectrical-mechanical

fabrication techniques exhibit promise in the field of neuronal

tissue engineering because the shape is highly controllable and a variety of materials can

be used in creation of bioreactors. This work evaluates the ability of a free standing TiO2

coated fractal scaffold to support healthy neuronal growth. Also evaluated is the

propensity for the neurons to take advantage of the 3D growing surface without the use of

complex extracellular matrix factors over the ...


A Biomechanical Assessment Of Canine Body Armor, Sarah Stojsih Jan 2015

A Biomechanical Assessment Of Canine Body Armor, Sarah Stojsih

Wayne State University Dissertations

The purpose of this research was to establish a biomechanical assessment of canine body armor with a primary focus on civilian law enforcement canines. The specific aims included: 1) the compilation of canine casualty data to determine commonly reported causes of death/euthanasia while in service for civilian law enforcement canines, 2) the evaluation of the biomechanical response of the canine related to a behind armor blunt impact, 3) the identification of an injury criterion that will best predict canine thoracic injury as a result of behind armor blunt trauma, 4) correlation of the behind armor blunt trauma response to ...


Novel Incorportation Of Biomedical Engineering Algorithms (Bispectral Index Guided Or Anesthetic Concentration Guided) In Real-Time Decision Support To Prevent Intraoperative Awareness Using An Electronic Anesthesia Information Mananagement System, Amy Melanie Shanks Jan 2015

Novel Incorportation Of Biomedical Engineering Algorithms (Bispectral Index Guided Or Anesthetic Concentration Guided) In Real-Time Decision Support To Prevent Intraoperative Awareness Using An Electronic Anesthesia Information Mananagement System, Amy Melanie Shanks

Wayne State University Dissertations

Background: Intraoperative awareness with explicit recall (AWR) is a feared complication of surgery that can lead to significant psychological distress. Several large prospective trials have been completed comparing two methods of monitoring anesthetic depth [minimum alveolar concentration (MAC) or electroencephalography (EEG) monitoring using the bispectral index (BIS)] for the prevention of AWR. However, these trials were conducted in high risk populations, limiting generalizability.

Research Hypothesis: Real-time decision support with Anesthesia Information Management System alerts based on a novel anesthetic concentration algorithm (incorporating the use of intravenous anesthetics) or an EEG-guided algorithm will reduce the known incidence of AWR.

Methods: First ...


Quantifying Magnetic Moments And Susceptibilities Of Small Cylindrical And Spherical Objects In Mri, Ching-Yi Hsieh Jan 2015

Quantifying Magnetic Moments And Susceptibilities Of Small Cylindrical And Spherical Objects In Mri, Ching-Yi Hsieh

Wayne State University Dissertations

Purpose: The purpose of this PhD work is to develop a method for accurately quantifying effective magnetic moments and susceptibility of either cylindrical or spherical-like small objects from magnetic resonance imaging (MRI). A standard 3D gradient echo sequence with only one echo time is intended for our approach to measure the effective magnetic moment of a given object of interest. For the quantification of the susceptibility in the cylindrical objects at different orientations, a standard 3D gradient echo sequence with only one or two echo times is needed.

Methods: Our method is to sum over complex MR signals around the ...


Development Of Scaffold Architectures And Heterotypic Cell Systems For Hepatocyte Transplantation, Dalia Alzebdeh Jan 2015

Development Of Scaffold Architectures And Heterotypic Cell Systems For Hepatocyte Transplantation, Dalia Alzebdeh

Wayne State University Dissertations

In vitro assembly of functional liver tissue is needed to enable the transplantation of tissue-engineered livers. In addition, there is an increasing demand for in vitro models that replicate complex events occurring in the liver. However, tissue engineering of sizable implantable liver systems is currently limited by the difficulty of assembling three dimensional hepatocyte cultures of a useful size, while maintaining full cell viability, an issue which is closely related to the high metabolic rate of hepatocytes. In this study, we first compared two designs of highly porous chitosan-heparin scaffolds seeded with hepatocytes in dynamic perfusion bioreactor systems. The aim ...