Biomedical Engineering and Bioengineering Commons^™

Attenuation Based Quantification Of Interstitial Lung Disease Using High Resolution Computed Tomography And Correlation With Pulmonary Function Tests, Snehal S. Watharkar

Bioengineering Theses - Archive

Interstitial lung disease (ILD) is a chronic and progressive pulmonary disease of the lung parenchyma resulting in fibrotic scar formation of the pulmonary alveoli. The pathologic changes in the lung result in restrictive impairment of lung function. High resolution computed tomography (HRCT) of the chest has become an essential technique in diagnosing and assessing the extent of ILD. Clinical evaluation by HRCT is usually qualitative, leading to inter-observer variability particularly in detecting early disease. We propose a quantitative attenuation-based analysis to standardize the assessment of regional lung disease. We hypothesize that early ILD is associated with greater regional heterogeneity than …

Transgenic Rat Model Of Neurodegeneration Caused By Mutation In The Tdp Gene, Hongxia Zhou, Cao Huang, Han Chen, Dian Wang, Carlisle P. Landel, Pedro Yuxing Xia, Robert Bowser, Yong-Jian Liu, Xu Gang Xia

Nebraska Center for Biotechnology: Faculty and Staff Publications

TDP-43 proteinopathies have been observed in a wide range of neurodegenerative diseases. Mutations in the gene encoding TDP-43 (i.e., TDP) have been identified in amyotrophic lateral sclerosis (ALS) and in frontotemporal lobe degeneration associated with motor neuron disease. To study the consequences of TDP mutation in an intact system, we created transgenic rats expressing normal human TDP or a mutant form of human TDP with a M337V substitution. Overexpression of mutant, but not normal, TDP caused widespread neurodegeneration that predominantly affected the motor system. TDP mutation reproduced ALS phenotypes in transgenic rats, as seen by progressive degeneration of motor neurons …

Effect Of Magnetron Frequency On Heating Pattern In Domestic Oven, Sohan Birla, Krishnamoorthy Pitchai, Jeyamkondan Subbiah, David D. Jones

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

In this study a computer model was developed to simulate microwave heating of a model food with a range of magnetron frequencies. The range was decided upon performing the frequency spectrum analysis of microwave leakage from the microwave oven. Simulation results showed that the magnetron input as sinusoidal frequency from 2.44 GHz to 2.48 GHz generates different heating profiles. The simulated heating profiles were compared with experimental heating profiles obtained by using an IR camera. None of simulations with individual frequency exactly matches with experimental temperature profile. The closet match between simulated and observed temperature profiles was found with 2.46 …

Sodium Hydroxide Pretreatment And Enzymatic Hydrolysis Of Coastal Bermuda Grass, Ziyu Wang, Deepak R. Keshwani, Arthur P. Redding, Jay J. Cheng

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Coastal Bermuda grass was pretreated with NaOH at concentrations from 0.5% to 3% (w/v) for a residence time from 15 to 90 minutes at 121 °C. The pretreatments were evaluated based on total lignin removal and production of total reducing sugars, glucose and xylose from enzymatic hydrolysis of the pretreated biomass. Up to 86% lignin removal was observed. The optimal NaOH pretreatment conditions at 121 °C for total reducing sugars production as well as glucose and xylose yields are 15 minutes and 0.75% NaOH. Under these optimal pretreatment conditions, total reducing sugars yield was about 71% of the theoretical maximum, …

Modeling Changes In Biomass Composition During Microwave-Based Alkali Pretreatment Of Switchgrass, Deepak R. Keshwani, Jay J. Cheng

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This study used two different approaches to model changes in biomass composition during microwave-based pretreatment of switchgrass: kinetic modeling using a time-dependent rate coefficient, and a Mamdani-type fuzzy inference system. In both modeling approaches, the dielectric loss tangent of the alkali reagent and pretreatment time were used as predictors for changes in amounts of lignin, cellulose, and xylan during the pretreatment. Training and testing data sets for development and validation of the models were obtained from pretreatment experiments conducted using 1–3% w/v NaOH (sodium hydroxide) and pretreatment times ranging from 5 to 20 minutes. The kinetic modeling approach for lignin …

Dual-Stage Sugar Substitution In Strawberries With A Stevia-Based Sweetener, Juan Garcia-Noguera, Curtis L. Weller, Francisca I. P. Oliveira, Sueli Rodrigues, Fabiano A. N. Fernandes

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The present study introduces and analyzes a new process denominated dual-stage sugar substitution (D3S). This process aims to induce sugar substitution in strawberries. In a first stage, high-calorie sugars (sucrose, fructose and glucose) are partially removed from the fruit samples and in a second stage, low-calorie sugar (stevioside and rebaudioside) is incorporated to the fruit to maintain its sweetness. The process was evaluated by studying the use of ultrasound application in one or both stages of the D3S process. Best performance of the process was obtained by subjecting the fruit samples to ultrasound in the sugar removal stage followed by …

Cytocompatible Cross-Linking Of Electrospun Zein Fibers For The Development Of Water-Stable Tissue Engineering Scaffolds, Quiran Jiang, Narendra Reddy, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This paper reports a new method of cross-linking electrospun zein fibers using citric acid as a non-toxic cross-linker to enhance the water stability and cytocompatibility of zein fibers for tissue engineering and other medical applications. The electrospun structure has many advantages over other types of structures and protein-based biomaterials possess unique properties preferred for tissue engineering and other medical applications. However, ultrafine fiber matrices developed from proteins have poor mechanical properties and morphological stability in the aqueous environments required for medical applications. Efforts have been made to improve the water stability of electrospun protein scaffolds using cross-linking and other approaches, …

Microwave-Based Alkali Pretreatment Of Switchgrass And Coastal Bermudagrass For Bioethanol Production, Deepak R. Keshwani, Jay J. Cheng

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Switchgrass and coastal bermudagrass are promising lignocellulosic feedstocks for bioethanol production. However, pretreatment of lignocelluloses is required to improve production of fermentable sugars from enzymatic hydrolysis. Microwave-based alkali pretreatment of switchgrass and coastal bermudagrass was investigated in this study. Pretreatments were carried out by immersing the biomass in dilute alkali reagents and exposing the slurry to microwave radiation at 250 W for residence times ranging from 5 to 20 minutes. Simons’ stain method was used to quantify changes in biomass porosity as a result of the pretreatment. Pretreatments were evaluated based on yields of total reducing sugars, glucose, and xylose. …

Retrofit Of Distillation Columns In Biodiesel Production Plants, Nghi Nguyen, Yaşar Demirel

Yaşar Demirel Publications

Column grand composite curves and the exergy loss profiles produced by the Column-Targeting Tool of the Aspen Plus simulator are used to assess the performance of the existing distillation columns, and reduce the costs of operation by appropriate retrofits in a biodiesel production plant. Effectiveness of the retrofits is assessed by means of thermodynamics and economic improvements. We have considered a biodiesel plant utilizing three distillation columns to purify biodiesel (fatty acid methyl ester) and byproduct glycerol as well as reduce the waste. The assessments of the base case simulation have indicated the need for modifications for the distillation columns. …

Nonequilibrium Thermodynamics Modeling Of Coupled Biochemical Cycles In Living Cells, Yaşar Demirel

Yaşar Demirel Publications

Living cells represent open, nonequilibrium, self organizing, and dissipative systems maintained with the continuous supply of outside and inside material, energy, and information flows. The energy in the form of adenosine triphosphate is utilized in biochemical cycles, transport processes, protein synthesis, reproduction, and performing other biological work. The processes in molecular and cellular biological systems are stochastic in nature with varying spatial and time scales, and bounded with conservation laws, kinetic laws, and thermodynamic constraints, which should be taken into account by any approach for modeling biological systems. In component biology, this review focuses on the modeling of enzyme kinetics …

Quantification Of Vascular Parametric Indices Using Dynamic Contrast-Enhanced Magnetic Resonance Imaging, Areen Khaled Al.Bashir

Wayne State University Dissertations

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a non-invasive method used to evaluate the biological activity in early clinical trials of novel drugs targeting the tumor vasculature using gadolinium-DTPA (Gd) as a contrast agent. However, it has some limitations, such as reproducibility, data acquisition times, the presence of noise, extracting contrast concentration, estimating T1 relaxation and estimating pharmacokinetic parameters.

In this work, a new approach to used fixed T1(0) which provides more reproducible DCE results has been introduced. Using this new algorithm to quantify the vascular changes in DCE-MRI, a pre-clinical renal cell carcinoma (RCC) tumor model was used to …

Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, Pradeep R. Nair, Muhammad A. Alam

Birck and NCN Publications

Modern label-free biosensors are generally far more sensitive and require orders of magnitude less incubation time compared to their classical counterparts. However, a more important characteristic regarding the viability of this technology for applications in Genomics/Proteomics is defined by the ‘Selectivity’, i.e., the ability to concurrently and uniquely detect multiple target biomolecules in the presence of interfering species. Currently, there is no theory of Selectivity that allows optimization of competing factors and there are few experiments to probe this problem systematically. In this article, we use the elementary considerations of surface exclusion, diffusion limited transport, and void distribution function to …

Development Of Magnetic-Based Core-Shell Nanoparticles For Drug Delivery Applications In Melanoma Skin Cancer, Zarna A. Bhavsar

Bioengineering Theses - Archive

Melanoma skin cancer is the most dangerous form of skin cancer and the major cause of deaths related to skin cancer worldwide. Conventional chemotherapeutic treatment is not very effective and faces many problems such as low response rate, development of multidrug resistance, and severe side effects. In order to address these limitations and improve melanoma treatment efficacy, development of a multifunctional nanoparticulate drug delivery system is desired. Thus, we aimed towards the development of magnetic-based core-shell nanoparticles (MBCS NPs) for dual drug release and dual targeting of melanoma tumors. The synthesized nanoparticles were composed of Poly (Lactic-co-glycolic acid) (PLGA) particle …

A Novel Injectable Porous Hydrogel Composite Scaffold For Bone Tissue Engineering, Parvathi Nair

Bioengineering Theses - Archive

Over the past decade there has been an increasing use of bone grafts for orthopedic applications. With the aging US population, the need for suitable bone grafts substitutes has also increased. The aim of this study was to develop a novel in situ crosslinkable hydrogel composite for tissue-engineering critical-sized bone defects. This system consists of a newly developed water-soluble biodegradable hydrogel Poly ((ethylene glycol) maleate citrate) (PEGMC) and hydroxyapatite (HA). The PEGMC/HA system is completely injectable and can be crosslinked in situ into crosslinked PEGMC/HA (CPEGMC/HA) hydrogel composite with or without poly (ethylene glycol) diacrylate (PEGDA) as a crosslinker. The …

Microfluidic Systems For Studying Cell Motility, Srikanth Vasudevan

Bioengineering Theses - Archive

It is very imperative to develop new in vitro platforms that can help in studying the complex interactions that occur between cell-Extracellular Matrix proteins and also during the process of cell migration in vivo. Such tools would facilitate in better understanding of the mechanisms that are employed by the cells during growth and migration. There are two devices that are presented in this study; 1) Multi-biomolecule coated lane device for unbiased cell preferential migration and 2) Novel Microchannel device for real time monitoring of tumor cell migration.The Multi-biomolecule coated lane device is a basic in vitro platform that helps in …

Electroporation-Mediated Delivery Of A Naked Dna Plasmid Expressing Vegf To The Porcine Heart Enhances Protein Expression, W. G. Marshall Jr., B. A. Boone, J. D. Burgos, S. I. Gografe, M. K. Baldwin, M. L. Danielson, M. J. Larson, D. R. Caretto, Y. Cruz, B. Ferraro, L. C. Heller, K. E. Ugen, M. J. Jaroszeski, R. Heller

Bioelectrics Publications

Gene therapy is an attractive method for the treatment of cardiovascular disease. However, using current strategies, induction of gene expression at therapeutic levels is often inefficient. In this study, we show a novel electroporation (EP) method to enhance the delivery of a plasmid expressing an angiogenic growth factor (vascular endothelial growth factor, VEGF), which is a molecule previously documented to stimulate revascularization in coronary artery disease. DNA expression plasmids were delivered in vivo to the porcine heart with or without coadministered EP to determine the potential effect of electrically mediated delivery. The results showed that plasmid delivery through EP significantly …

Digital Human Models Of People With Disabilities, Ron Hamameh

Wayne State University Theses

The current state-of-the-art in Digital Human Modeling (DHM) allows for full simulation and analysis of any task a person is required to perform at home, at work, in the military, in space, in sports, etc. The problem is that the software is missing a very important population: people with physical disabilities. What modifications and enhancements must be made to existing, commercially available DHM software to include this population?

Application Of Magnetic Resonance Imaging To Understanding The Pathogenesis Of The X-Linked Leukodystrophy Pelizaeus-Merzbacher Disease, Jeremy Jerome Laukka

Wayne State University Dissertations

Myelin is a multilamellar membrane structure surrounding axons in both the CNS and PNS that facilitates nerve conduction. In the CNS, myelin is synthesized by oligodendrocytes, while in the PNS, myelin is synthesized by Schwann cells. In the CNS, Proteolipid protein 1 (PLP1), an integral membrane protein, is the major protein component of myelin, constituting ~50% of myelin protein. Mutations of the PLP1 gene in man cause a spectrum of neurological disease, ranging from the severe Pelizaeus-Merzbacher disease (PMD), that typically begins during infancy with nystagmus, seizures and hypotonia and evolves into spastic quadriparesis, cognitive impairment and ataxia, to ¡¥pure¡¦ …

Nanivid : A New Research Tool For Tissue Microenvironment Studies, Waseem Khan Raja

Legacy Theses & Dissertations (2009 - 2024)

Metastatic tumors are heterogeneous in nature and composed of subpopulations of cells having various metastatic potentials. The time progression of a tumor creates a unique microenvironment to improve the invasion capabilities and survivability of cancer cells in different microenvironments. In the early stages of intravasation, cancer cells establish communication with other cell types through a paracrine loop and covers long distances by sensing growth factor gradients through extracellular matrices. Cellular migration both in vitro and in vivo is a complex process and to understand their motility in depth, sophisticated techniques are required to document and record events in real time. …

Implementation Of Risk Management In The Medical Device Industry, Rachelo Dumbrique

Master's Theses

This study looks at the implementation and effectiveness of risk management (RM) activities in the medical device industry. An online survey was distributed to medical device professionals who were asked to identify RM-related activities performed during the device life cycle. RM activities and techniques included Establishing Risk Acceptance Criteria, Hazard Identification, Human Factors/Usability, Fault Tree Analysis (FTA), Design Failure Mode and Effects Analysis (DFMEA), Process Failure Mode and Effects Analysis (PFMEA), Hazard and Operability Study (HAZOP), Hazard Analysis and Critical Control Point (HACCP), Risk Benefit Analysis, and Risk Assessment of Customer Complaint. Devices were identified by type (therapeutic, surgical/clinical tools, …