Biomedical Engineering and Bioengineering Commons^™

In Vitro Ovarian Tumor Growth And Treatment Response Dynamics Visualized With Time-Lapse Oct Imaging, Conor L. Evans, Imran Rizvi, Tayyaba Hasan, Johannes F. De Boer

Dartmouth Scholarship

In vitro three-dimensional models for metastatic ovarian cancer have been useful for recapitulating the human disease. These spheroidal tumor cultures, however, can grow in excess of 1 mm in diameter, which are difficult to visualize without suitable imaging technology.Optical coherence tomography (OCT) is an ideal live imaging method for non-perturbatively visualizing these complex systems. OCT enabled detailed observations of the model at both nodular and cellular levels, revealing growth dynamics not previously observed. The development of a time-lapse OCT system, capable of automated, multidimensional acquisition, further provided insights into the growth and chemotherapeutic response of ovarian cancer.

A Model For Electrical Communication Between Cochlear Implants And The Brain, Douglas A. Miller

Electronic Theses and Dissertations

In the last thirty years, cochlear implants have become an invaluable instrument in the treatment of severe-to-profound hearing impairment. An important aspect of research in the continued development of cochlear implants is the in vivo assessment of signal processing algorithms intended to improve perception of speech and other auditory signals. In trying to determine how closely cochlear implant recipients process sound relative to the processing done by a normal auditory system, various assessment techniques have been applied. The most common technique has been measurement of auditory evoked potentials (AEPs), which involves the recording of neural responses to auditory stimulation. Depending …

A New Pulsed Electric Field Therapy For Melanoma Disrupts The Tumor's Blood Supply And Causes Complete Remission Without Recurrence, Richard Nuccitelli, Xinhua Chen, Andrei G. Pakhomov, Wallace H. Baldwin, Saleh Sheikh, Jennifer L. Pomicter, Wei Ren, Chris Osgood, R. James Swanson, Juergen F. Kolb, Stephen J. Beebe, Karl H. Schoenbach

Bioelectrics Publications

We have discovered a new, ultrafast therapy for treating skin cancer that is extremely effective with a total electric field exposure time of only 180 mu sec. The application of 300 high-voltage (40 kV/cm), ultrashort (300 nsec) electrical pulses to murine melanomas in vivo triggers both necrosis and apoptosis, resulting in complete tumor remission within an average of 47 days in the 17 animals treated. None of these melanomas recurred during a 4-month period after the initial melanoma had disappeared. These pulses generate small, long-lasting, rectifying nanopores in the plasma membrane of exposed cells, resulting in increased membrane permeability to …

Cold Plasma Technology: Bactericidal Effects On Geobacillus Stearothermophilus And Bacillus Cereus Microorganisms, Angela D. Morris, Gayle B. Mccombs, Tamer Akan, Wayne L. Hynes, Mounir Laroussi, Susan L. Tolle

Dental Hygiene Faculty Publications

Introduction: Cold plasma, also known as Low Temperature Atmospheric Pressure Plasma (LTAPP) is a novel technology consisting of neutral and charged particles, including free radicals, which can be used to destroy or inactivate microorganisms. Research has been conducted regarding the effect of cold plasma on gram-positive bacteria; however, there is limited research regarding its ability to inactivate the spore-formers Geobacillus stearothermophilus and Bacillus cereus.

Purpose: The purpose of this study was to determine if cold plasma inactivates G. stearothermophilus and B. cereus vegetative cells and spores.

Methods: Nine hundred eighty-one samples were included in this study (762 experimental and …

Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia

Master's Theses (2009 -)

Coarctation of the aorta (CoA) is a major congenital heart disease, characterized by a severe stenosis of the proximal descending thoracic aorta. Traditionally, surgery has been the treatment of choice for CoA. Dacron patch aortoplasty gained increased popularity after its introduction in the mid-twentieth century due to its advantages over other surgical treatment methods available at the time. A major complication with Dacron patch aortoplasty has been the formation of late aneurysm with as much as 51% incidence reported in follow up studies. The change in aortic morphology and formation of aneurysms after Dacron patch surgery could lead to local …

Biocompatibility Of Poly-Ε-Caprolactone-Hydroxyapatite Composite On Mouse Bone Marrow-Derived Osteoblasts And Endothelial Cells, Haiying Yu, Paul H. Wooley, Shang-You Yang

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Tissue-engineered bone may be developed by seeding the cells capable of both osteogenesis and vascularization on biocompatible composite scaffolds. The current study investigated the performance of mice bone marrow-derived osteogenic cells and endothelial cells as seeded on hydroxyapatite (HA) and poly-ε-caprolactone (PCL) composite scaffolds.

Methods

Mononuclear cells were induced to osteoblasts and endothelial cells respectively, which were defined by the expression of osteocalcin, alkaline phosphatase (ALP), and deposits of calcium-containing crystal for osteoblasts, or by the expression of vascular endothelial growth factor receptor-2 (VEGFR-2) and von Willebrand factor (vWF), and the formation of a capillary network in Matrigel™ …

Optimizing Computer-Aided Colonic Polyp Detection For Ct Colonography By Evolving The Pareto Front, Jiang Li, Adam Huang, Jack Tao, Jiamin Liu, Robert L. Van Uitert, Nicholas Petrick, Ronald Summers

Electrical & Computer Engineering Faculty Publications

A multiobjective genetic algorithm is designed to optimize a computer-aided detection (CAD) system for identifying colonic polyps. Colonic polyps appear as elliptical protrusions on the inner surface of the colon. Curvature-based features for colonic polyp detection have proved to be successful in several CT colonography (CTC) CAD systems. Our CTC CAD program uses a sequential classifier to form initial polyp detections on the colon surface. The classifier utilizes a set of thresholds on curvature-based features to cluster suspicious colon surface regions into polyp candidates. The thresholds were previously chosen experimentally by using feature histograms. The chosen thresholds were effective for …

Parameter Optimization For Image Denoising Based On Block Matching And 3d Collaborative Filtering, Ramu Pedada, Emin Kugu, Jiang Li, Zhanfeng Yue, Yuzhong Shen, Josien P.W. Pluim (Ed.), Benoit M. Dawant (Ed.)

Electrical & Computer Engineering Faculty Publications

Clinical MRI images are generally corrupted by random noise during acquisition with blurred subtle structure features. Many denoising methods have been proposed to remove noise from corrupted images at the expense of distorted structure features. Therefore, there is always compromise between removing noise and preserving structure information for denoising methods. For a specific denoising method, it is crucial to tune it so that the best tradeoff can be obtained. In this paper, we define several cost functions to assess the quality of noise removal and that of structure information preserved in the denoised image. Strength Pareto Evolutionary Algorithm 2 (SPEA2) …

Automatic Diagnosis For Prostate Cancer Using Run-Length Matrix Method, Xiaoyan Sun, Shao-Hui Chuang, Jiang Li, Frederic Mckenzie, Nico Karssemeijer (Ed.), Maryellen L. Giger (Ed.)

Electrical & Computer Engineering Faculty Publications

Prostate cancer is the most common type of cancer and the second leading cause of cancer death among men in US¹. Quantitative assessment of prostate histology provides potential automatic classification of prostate lesions and prediction of response to therapy. Traditionally, prostate cancer diagnosis is made by the analysis of prostate-specific antigen (PSA) levels and histopathological images of biopsy samples under microscopes. In this application, we utilize a texture analysis method based on the run-length matrix for identifying tissue abnormalities in prostate histology. A tissue sample was collected from a radical prostatectomy, H&E fixed, and assessed by a pathologist …

Spectral Analysis Of Pathological Acoustic Speech Waveforms, Priyanka Medida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biomedical engineering is the application of engineering principles and techniques to the medical field. The design and problem solving skills of engineering are combined with medical and biological science, which improves medical disorder diagnosis and treatment. The purpose of this study is to develop an automated procedure for detecting excessive jitter in speech signals, which is useful for differentiating normal from pathologic speech. The fundamental motivation for this research is that tools are needed by speech pathologists and laryngologists for use in the early detection and treatment of laryngeal disorders. Acoustical analysis of speech was performed to analyze various features …

Trunk Response Analysis Under Sudden Forward Perturbations Using A Kinematics-Driven Model, B. Bazrgari, A. Shirazi-Adl, Christian Larivière

Études primaires

No abstract provided.

Methodology Development For Three-Dimensional Mr-Guided Near Infrared Spectroscopy Of Breast Tumors, Colin M. Carpenter, Subhadra Srinivasan, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

Combined Magnetic Resonance (MR) and Near Infrared Spectroscopy (NIRS) has been proposed as a unique method to quantify hemodynamics, water content, and cellular size and packing density of breast tumors, as these tissue constituents can be quantified with increased resolution and overlaid on the structural features identified by the MR. However, the choices in how to reconstruct and visualize this information can have a dramatic impact on the feasibility of implementing this modality in the clinic. This is especially true in 3 dimensions, as there is often limited optical sampling of the breast tissue, and methods need to accurately reflect …

Cephalometric Analysis Using Magnetic Resonance Imaging, Wade A. Williams

Loma Linda University Electronic Theses, Dissertations & Projects

Purpose: The purpose of this study was to determine if T1-weighted 3D magnetic resonance images performed at 3.0 Tesla could be used to conduct routine orthodontic cephalometric analysis.

Methods: Three cranial imaging methods were compared using sixteen non-growing subjects (10 male and 6 female) who were not claustrophobic, did not have any metallic restorations on the distal of first molars, had no medical implants and the female subjects were not pregnant. Sagittal cranial images were produced by three methods: (1) a digital lateral cephalometric (LC) radiograph (Orthophos XG Plus, Sirona^TM, Bensheim, Germany), (2) a 12-inch FOV cone beam …

Image-Guided Raman Spectroscopic Recovery Of Canine Cortical Bone Contrast In Situ, Subhadra Srinivasan, Matthew Schulmerich, Jacqueline H. Cole, Kathryn Dooley, Jaclynn M. Kreider, Brian W. Pogue

Dartmouth Scholarship

Raman scattering provides valuable biochemical and molecular markers for studying bone tissue composition with use in predicting fracture risk in osteoporosis. Raman tomography can image through a few centimeters of tissue but is limited by low spatial resolution. X-ray computed tomography (CT) imaging can provide high-resolution image-guidance of the Raman spectroscopic characterization, which enhances the quantitative recovery of the Raman signals, and this technique provides additional information to standard imaging methods. This hypothesis was tested in data measured from Teflon tissue phantoms and from a canine limb. Image-guided Raman spectroscopy (IG-RS) of the canine limb using CT images of the …

Medical Image Modeling And Processing, Ramu Pedada

Electrical & Computer Engineering Theses & Dissertations

During the last few decades of the twentieth century, medical imaging has been playing a prominent role in many fields of biomedical research and clinical practice. Image modalities such as x-rays, computed tomography (CT), and magnetic resonance images (MRI) have all been valuable additions to the radiologist's arsenal of imaging tools. Medical images assure quality diagnosis and patient safety by gathering valuable information without invading the human body. Apart from clinical diagnosis, medical images are used as tools for education where they are used for training individuals before operating on a patient. Many medical educators tum to simulation based training …

Fluorescence Tomography Characterization For Sub-Surface Imaging With Protoporphyrin Ix, Dax Kepshire, Scott C. Davis, Hamid Dehghani, Keith D. Paulsen, Brian W. Pogue

Dartmouth Scholarship

Optical imaging of fluorescent objects embedded in a tissue simulating medium was characterized using non-contact based approaches to fluorescence remittance imaging (FRI) and sub-surface fluorescence diffuse optical tomography (FDOT). Using Protoporphyrin IX as a fluorescent agent, experiments were performed on tissue phantoms comprised of typical in-vivo tumor to normal tissue contrast ratios, ranging from 3.5:1 up to 10:1. It was found that tomographic imaging was able to recover interior inclusions with high contrast relative to the background; however, simple planar fluorescence imaging provided a superior contrast to noise ratio. Overall, FRI performed optimally when the object was located on or …

Real-Time Ultrasound Simulation For Medical Training And Standardized Patient Assessment, Bo Sun

Computational Modeling & Simulation Engineering Theses & Dissertations

With the increasing role played by ultrasound in clinical diagnostics, ultrasound training in medical education has become more and more important. The clinical routine for ultrasound training is on real patients; therefore monitored and guided examinations involving medical students are quite time-constrained. Furthermore, standardized patients (SPs), who are increasingly used in medical school for teaching and assessing medical students, need to be augmented. These SPs are typically healthy individuals who can not accurately portray the variety of abnormalities that are needed for training especially when medical examinations involve instrument interactions. To augment SPs in a realistically effective way and also …

An Approach To Identifying The Biomechanical Differences Between Intercostal Cartilage In Subjects With Pectus Excavatum And Normals In Vivo: Reconstruction And Ct Registration, Zhenzhen Yan

Electrical & Computer Engineering Theses & Dissertations

Pectus excavatum (PE) is a congenital chest wall deformity affecting the ribs and sternum and exhibiting a concave appearance in the anterior chest wall. In this thesis, we describe a study to investigate in vivo differences in the pectus excavatum rib cage and outline steps using normals and pectus patients data in developing models and methods to be used in carrying out the study. We propose methods to develop reconstructed models in order to enable proper registration between data collection points (DCPs) on the 3D CT rib cage model and CT skin surface model and registration between CT surrogate models …

The Application Of Innovative High-Throughput Techniques To Serum Biomarker Discovery, Izabela Debkiewicz Karbassi

Theses and Dissertations in Biomedical Sciences

Time-of-flight mass spectrometry continues to evolve as a promising technique for serum protein expression profiling and biomarker discovery. As seen in our initial SELDI-TOF MS and MALDI-TOF MS profiling study of serum for the assessment of breast cancer risk, many profiling strategies typically employ single chemical affinity beads or surfaces to decrease sample complexity of dynamic fluids like serum. However, most proteins, captured on a particular surface or bead, are not resolved in the lower mass range where mass spectrometers are most effective. To this end we have designed an expression profiling workflow that utilizes immobilized trypsin paramagnetic beads in …

Generation Of Recombinant Mouse Embryonic Stem Cell Lines And Theirapplication For In Vivo Bioluminiscence Imaging In The Heart, Ramana Kammili

Electronic Theses and Dissertations

Cardiovascular disease is the major cause of death in the United States, with 80 million people suffering from some form of heart disease each year. One major limitation is the inability of the heart to repair the damaged tissue. Stem cell therapy holds enormous promise to repair and regenerate the damaged myocardium, but there are many technical difficulties that must first be overcome. One such difficulty is the present lack of ability to track and assess transplanted stem cells over time in vivo. The central hypothesis of this thesis is that in vivo bioluminescence imaging is a safe and useful …

Detailed Characterization Of The Mouse Embryonic Stem Cell Transcriptome Reveals Novel Genes And Intergenic Splicing Associated With Pluripotency, Galih Kunarso, Kee-Yew Wong, Lawrence W. Stanton, Leonard Lipovich

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Transcriptional control of embryonic stem (ES) cell pluripotency has been a subject of intense study. Transcriptional regulators including Oct4 (Oct3/4 index), Sox2 and Nanog are fundamental for maintaining the undifferentiated state. However, the ES cell transcriptome is not limited to their targets, and exhibits considerable complexity when assayed with microarray, MPSS, cDNA/EST sequencing, and SAGE technologies. To identify novel genes associated with pluripotency, we globally searched for ES transcripts not corresponding to known genes, validated their sequences, determined their expression profiles, and employed RNAi to test their function.

Results

Gene Identification Signature (GIS) analysis, a SAGE derivative distinguished …

Rule-Based Mamdani-Type Fuzzy Modeling Of Skin Permeability, Deepak R. Keshwani, David D. Jones, George E. Meyer, Rhonda M. Brand

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Two Mamdani type fuzzy models (three inputs–one output and two inputs–one output) were developed to predict the permeability of compounds through human skin. The models were derived from multiple data sources including laboratory data, published data bases, published statistical models, and expert opinion. The inputs to the model include information about the compound (molecular weight and octonal–H₂O partition coefficient) and the application temperature. One model included all three parameters as inputs and the other model only included information about the compound. The values for mole molecular weight ranged from 30 to 600 Da. The values for the log …

N-Glycan Modification In Aspergillus Species, Elke Kainz, Andreas Gallmetzer, Christian Hatzl, Juergen H. Nett, Huijuan Li, Thorsten Schinko, Robert Pachlinger, Harald Berger, Yazmid Reyes-Dominguez, Andreas Bernreiter, Tillmann Gerngross, Stefan Wildt, Joseph Strauss

Dartmouth Scholarship

The production by filamentous fungi of therapeutic glycoproteins intended for use in mammals is held back by the inherent difference in protein N-glycosylation and by the inability of the fungal cell to modify proteins with mammalian glycosylation structures. Here, we report protein N-glycan engineering in two Aspergillus species. We functionally expressed in the fungal hosts heterologous chimeric fusion proteins containing different localization peptides and catalytic domains. . This strategy allowed the isolation of a strain with a functional -1,2-mannosidase producing increased amounts of N-glycans of the Man 5 GlcNAc 2 type. This strain was further engineered by the introduction of …

Bactericidal Effects Of Cold Plasma Technology On Geobacillus Stearothermophilus And Bacillus Cereus Microorganisms, Angela D. Morris, Gayle B. Mccombs, Susan L. Tolle, Mounir Laroussi, Wayne L. Hynes

Dental Hygiene Faculty Publications

Cold plasma is a state of matter that contains a large number of particles that are electrically charged. Plasmas generate chemically reactive species and ultraviolet radiation making them useful in decontamination applications (Kong & Laroussi, 2003). Research regarding the inactivation of gram-positive bacteria by cold plasma has been studied by Laroussi et al (2003); however, there is limited research regarding the germicidal effectiveness of cold plasma on Geobacillus stearothermophilus and Bacillus cereus microorganisms. The purpose of this study was to determine if cold plasma technology inactivates Geobacillus stearothermophilus and Bacillus cereus vegetative cells and spores. This study consisted of 981 …

Microfabrication Of An Optical Chamber For Exposing Living Cells To Pulsed Electric Fields, Saleh Sheikh

Electrical & Computer Engineering Theses & Dissertations

I have fabricated a chamber which enables the application of Nanosecond Pulsed Electric Fields (nsPEFs) to living cells while monitoring their real time fluorescence with an inverted microscope. The No. I thickness (150µm nominal) coverslip glass substrate used for fabrication allows the use of high numerical aperture oil immersion objectives for imaging intracellular organelles. Electrodes are fabricated by first evaporating a chromium adhesion layer, followed by a nickel seed layer. Subsequently, an ultra-thick positive photoresist is applied and patterned to create a 30µm thick electroplating mold. The electrodes are then electrodeposited into the mold from a nickel sulfamate plating bath. …

Simulation And Modeling Of Nerve Impulse Propagation And Its Blockage By External Electrical Stimulation, Nidhi Nahar

Electrical & Computer Engineering Theses & Dissertations

The electric nature of biological tissues permits the transmission of signals for information and for control and is, therefore, of vital importance for life. The latest scientific achievements and nanoscale probing techniques now allow scientists to research at the subcellular level by measuring the electric current flows through a single ion channel of the cell membrane with the patch-clamp method. With the latter approach, the effects of electrical stimulation can be quantified, understood, and applied to molecular biology and the development of medical diagnostic and therapeutic methods.

In this thesis, the Hodgkin-Huxley approach for unmyelinated fibers, coupled with a transmission …

Bioelectric Effects Of Intense Nanosecond Pulses, Karl H. Schoenbach, Barbara Y. Hargrave, Ravindra P. Joshi, Juergen F. Kolb, Richard Nuccitelli, Christopher J. Osgood, Andrei G. Pakhomov, Michael W. Stacey, James R. Swanson, Jody A. White, Shu Xiao, Jue Zhang, Stephen J. Beebe, Peter F. Blackmore, E. Stephen Buescher

Bioelectrics Publications

Electrical models for biological cells predict that reducing the duration of applied electrical pulses to values below the charging time of the outer cell membrane (which is on the order of 100 ns for mammalian cells) causes a strong increase in the probability of electric field interactions with intracellular structures due to displacement currents. For electric field amplitudes exceeding MV/m, such pulses are also expected to allow access to the cell interior through conduction currents flowing through the permeabilized plasma membrane. In both cases, limiting the duration of the electrical pulses to nanoseconds ensures only nonthermal interactions of the electric …

Using Pareto Fronts To Evaluate Polyp Detection Algorithms For Ct Colonography, Adam Huang, Jiang Li, Ronald M. Summers, Nicholas Petrick, Amy K. Hara

Electrical & Computer Engineering Faculty Publications

We evaluate and improve an existing curvature-based region growing algorithm for colonic polyp detection for our CT colonography (CTC) computer-aided detection (CAD) system by using Pareto fronts. The performance of a polyp detection algorithm involves two conflicting objectives, minimizing both false negative (FN) and false positive (FP) detection rates. This problem does not produce a single optimal solution but a set of solutions known as a Pareto front. Any solution in a Pareto front can only outperform other solutions in one of the two competing objectives. Using evolutionary algorithms to find the Pareto fronts for multi-objective optimization problems has been …

Validating Pareto Optimal Operation Parameters Of Polyp Detection Algorithms For Ct Colonography, Jiang Li, Adam Huang, Nicholas Petrick, Jianhua Yao, Ronald M. Summers, Maryellen L. Giger (Ed.), Nico Karssemeijer (Ed.)

Electrical & Computer Engineering Faculty Publications

We evaluated a Pareto front-based multi-objective evolutionary algorithm for optimizing our CT colonography (CTC) computer-aided detection (CAD) system. The system identifies colonic polyps based on curvature and volumetric based features, where a set of thresholds for these features was optimized by the evolutionary algorithm. We utilized a two-fold cross-validation (CV) method to test if the optimized thresholds can be generalized to new data sets. We performed the CV method on 133 patients; each patient had a prone and a supine scan. There were 103 colonoscopically confirmed polyps resulting in 188 positive detections in CTC reading from either the prone or …

The Effects Of Ultrashort Pulsed Electric Fields On The Fluorescent Molecule Bodipy Fl C5 Ceramide, Rachael Sara Shevin

Electrical & Computer Engineering Theses & Dissertations

Nanosecond pulsed electric fields are able to manipulate internal cell organelles by taking advantage of the small but finite time required for charge to establish across a capacitive barrier. Pulsed electric fields also affect macromolecular structures such as enzymes and proteins. Application of a single nanosecond pulsed electric field decreases the fluorescence of a commercially available biological dye Bodipy FL C₅ Ceramide, used to observe the Golgi apparatus of living cells. The effect is seen when the fluorophore is exposed to an electric field both in vitro and when incorporated into the Golgi of a living Jurkat cell. Observation …