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Full-Text Articles in Biomedical Engineering and Bioengineering

Intraocular Pressure Sensing And Control For Glaucoma Research, Simon Antonio Bello Nov 2016

Intraocular Pressure Sensing And Control For Glaucoma Research, Simon Antonio Bello

Graduate Theses and Dissertations

Animal models of ocular hypertension are important for glaucoma research but come with experimental costs. Available methods of intraocular pressure (IOP) elevation are not always successful, the amplitude and time course of IOP changes are unpredictable and irreversible, and IOP measurement by tonometry is laborious. This dissertation focuses on the development and implementation of two novel systems for monitoring and controlling IOP without these limitations. The first device consists of a cannula implanted in the anterior chamber of the eye, a pressure sensor that continually measures IOP, and a bidirectional pump driven by control circuitry that can infuse or withdraw ...


Corrosion Characteristics Of Magnesium Under Varying Surface Roughness Conditions, Yahya Efe Yayoglu Nov 2016

Corrosion Characteristics Of Magnesium Under Varying Surface Roughness Conditions, Yahya Efe Yayoglu

Graduate Theses and Dissertations

The biggest challenge with magnesium alloy biodegradable implants is the rapid corrosion at the earlier stages of the healing process after implantation. In this research, the impact of surface roughness generated by different means on the corrosion rate of AZ31 magnesium alloy in a simulated biologic environment is investigated. In order to perform accurate experimentation, an in vitro setup is assembled that simulates the human body environment accurately has been prepared using Schinhammer’s in vitro immersion testing setup and Kokubo’s Simulated Body Fluid (SBF). For the immersion test of Mg in SBF, several surface texture groups of Mg ...


Biomarker Detection At Risk Forecasting Level Using Metal-Enhanced Fluorescence Combined With Surface Acoustic Wave, Jun Liu Nov 2016

Biomarker Detection At Risk Forecasting Level Using Metal-Enhanced Fluorescence Combined With Surface Acoustic Wave, Jun Liu

Graduate Theses and Dissertations

In this paper, metal-enhanced fluorescence (MEF) technique is used to lower the detection limit of carcinoembryonic antigen (CEA) which is able to be utilized in forecasting the risk of having certain kinds of cancers, especially colon and rectal cancer. By incubating silver nanocubes (Ag NCs) on the surface of the chips, the detection limit goes down to below 1ng/mL of CEA. Also, when combining MEF with surface acoustic wave (SAW) devices, the incubation time between antigen and antibody will decrease significantly with the fluorescence signal keeping similar or higher level.


Mechanotransduction Of Matrix Stiffness Regulates Cell Adhesion Strength: An Analysis Using Biomaterial Surfaces With Tunable Mechanical And Chemical Properties, Asma Sharfeddin Sharfeddin Jul 2016

Mechanotransduction Of Matrix Stiffness Regulates Cell Adhesion Strength: An Analysis Using Biomaterial Surfaces With Tunable Mechanical And Chemical Properties, Asma Sharfeddin Sharfeddin

Graduate Theses and Dissertations

Cells have the ability to sense the rigidity of the extracellular matrix which directly affects the control of cellular functions in development, wound healing and malignant transformation. Polydimethylsiloxane elastomers are useful model biomaterials for mechanotransduction studies because they possess several advantages including ease of fabrication, tunable elasticity and modifiable surface chemistry. In this work, we are investigating the influence of matrix stiffness on adhesion strength and the mechanosensory structures that regulate these processes. In addition, the effect of surface modifications to this elastic substrate system on other physical properties such as local stiffness and topography will be analyzed. Based on ...


Differential Association Of Vitronectin And Fibronectin With Glass And Electrospun Fibers Of A Poly (D-Lysine) /Poly (Acrylic Acid), Syed Muhammad Sohaib Zafar Zafar Jul 2016

Differential Association Of Vitronectin And Fibronectin With Glass And Electrospun Fibers Of A Poly (D-Lysine) /Poly (Acrylic Acid), Syed Muhammad Sohaib Zafar Zafar

Graduate Theses and Dissertations

Proteins represent major constituent of the extracellular matrix which plays an important role in the formation, maintenance and remodeling of tissues, this project focuses on adsorption of two specific serum proteins fibronectin (FN) and vitronectin (VTN) responsible for mediating cell matrix interaction through integrin binding, tripeptide Arg-Gly-Asp (RGD) sequence found in these protein features are recognized by αβV3 integrin which ultimately helps in clot formation.


Tunable Nano-Delivery System For Cancer Treatment: A New Approach For Targeted Localized Drug Delivery, Rana Falahat Jun 2016

Tunable Nano-Delivery System For Cancer Treatment: A New Approach For Targeted Localized Drug Delivery, Rana Falahat

Graduate Theses and Dissertations

Localized drug delivery systems have been widely studied as potential replacements for conventional chemotherapy with the capability of providing sustained and controlled drug release in specific targeted sites. They offer numerous benefits over conventional chemotherapy such as enhancing the stability of embedded drugs and preserving their anticancer activity, providing sustained and controlled drug release in the tumor site, reducing toxicity and diminishing subsequent side effects, minimizing the drug loss, averting the need for frequent administrations, and minimizing the cost of therapy.

The aim of this study is to develop a localized drug delivery system with niosomes embedded in a chitosan ...


Biophysical Characterization And Theoretical Analysis Of Molecular Mechanisms Underlying Cell Interactions With Poly(N-Isopropylacrylamide) Hydrogels, Michael C. Cross Jun 2016

Biophysical Characterization And Theoretical Analysis Of Molecular Mechanisms Underlying Cell Interactions With Poly(N-Isopropylacrylamide) Hydrogels, Michael C. Cross

Graduate Theses and Dissertations

So-called, “Dynamic biomaterials” comprised of stimuli-responsive hydrogels are useful in a wide variety of biomedical applications including tissue engineering, drug delivery, and biomedical implants. More than 150,000 peer-reviewed articles (as of 2016) have been published on these materials, and more specifically, over 100,000 of these are on the most widely studied, poly(N-isopropylacrylamide). This thermoresponsive polymer in a crosslinked hydrogel network undergoes a large volume phase transition (𝑉/𝑉0 ~ 10 − 100) within a small temperature range (𝑇 ~ 1 − 3𝐾) making it particularly useful for tissue engineering applications because of the ability to control the topographical configuration of ...


The Development Of A Prosthetic Training Software For Upper Limb Amputees, Tyler Kayne Sullins Jun 2016

The Development Of A Prosthetic Training Software For Upper Limb Amputees, Tyler Kayne Sullins

Graduate Theses and Dissertations

The purpose of this study was to develop an intuitive software that aids in the field of prosthetic training and rehabilitation by creating an individualized visualization of joint angles. This software is titled “the prosthetic training software (PTS) for individualized joint angle representation”, and it enables the individualized portrayal of predicted or pre-recorded joint angles. The PTS is an intuitive program for clinicians and prosthesis users that produces an animation of a virtual avatar reflecting the user’s segment lengths and amputation for rehabilitation and training purposes.

The PTS consists of a graphical user interface (GUI) and a 3D visualization ...


Nano-Photonic Waveguides For Chemical And Biomedical Sensing, Surya Venkatasekhar Cheemalapati May 2016

Nano-Photonic Waveguides For Chemical And Biomedical Sensing, Surya Venkatasekhar Cheemalapati

Graduate Theses and Dissertations

In this dissertation, advances in the fields of Photonics, and Plasmonics, and specifically, single cell analysis and waveguide sensing will be addressed. The first part of the dissertation is on Finite Difference Time Domain (FDTD) optimization and experimental demonstration of a nano-scale instrument that allows sensing at the cellular and subcellular levels. A new design of plasmonic coupler into a nanoscale waveguide is proposed and optimized using FDTD simulations. Following this, a subcellular nanoendoscope that can locally excite fluorescence in labelled cell organelles and collect the emitted fluorescent light for detailed spectrum analysis is fabricated and tested. The nanoendoscope has ...


Graphene Quantum Dots-Based Drug Delivery For Ovarian Cancer Therapy, Yiru Qin May 2016

Graphene Quantum Dots-Based Drug Delivery For Ovarian Cancer Therapy, Yiru Qin

Graduate Theses and Dissertations

Ovarian cancer, one of the most dreadful malignancies of the female reproductive system, poses a lethal threat to women worldwide. In this dissertation, the objective was to introduce a novel type of graphene quantum dots (GQDs) based nano-sized drug delivery systems (DDS) for ovarian cancer treatment. As a starting point, the facile synthesis method of the GQDs was established. Subsequently, the targeting ligand,folic acid (FA), was conjugated to GQDs. Next, a FDA approved chemotherapeutic drug, Doxorubicin (DOX), was loaded to form the GQDs-FA-DOX nano-conjugation as the DDS. Moreover, the uptake profile and anti-cancer effect of the GQDs-FA-DOX were validated ...


Gait And Tremor Monitoring System For Patients With Parkinson’S Disease Using Wearable Sensors, Shyam Vignesh Perumal Apr 2016

Gait And Tremor Monitoring System For Patients With Parkinson’S Disease Using Wearable Sensors, Shyam Vignesh Perumal

Graduate Theses and Dissertations

Typically, a Parkinson’s disease (PD) patient would display instances of tremor and bradykinesia (slowness of movement) at an early stage of the disease and later develop gait disturbances and postural instability. So, it is important to measure the tremor occurrences in subjects to detect the onset of PD. Also, it is equally essential to monitor the gait impairments that the patient displays, as the order at which the PD symptoms appear in subjects vary from one to another.

The primary goal of this thesis is to develop a monitoring system for PD patients using wearable sensors. To achieve that ...


Increasing 18f-Fdg Pet/Ct Capabilities In Radiotherapy For Lung And Esophageal Cancer Via Image Feature Analysis, Jasmine Alexandria Oliver Mar 2016

Increasing 18f-Fdg Pet/Ct Capabilities In Radiotherapy For Lung And Esophageal Cancer Via Image Feature Analysis, Jasmine Alexandria Oliver

Graduate Theses and Dissertations

Positron Emission Tomography (PET) is an imaging modality that has become increasingly beneficial in Radiotherapy by improving treatment planning (1). PET reveals tumor volumes that are not well visualized on computed tomography CT or MRI, recognizes metastatic disease, and assesses radiotherapy treatment (1). It also reveals areas of the tumor that are more radiosensitive allowing for dose painting - a non-homogenous dose treatment across the tumor (1). However, PET is not without limitations. The quantitative unit of PET images, the Standardized Uptake Value (SUV), is affected by many factors such as reconstruction algorithm, patient weight, and tracer uptake time (2). In ...


Modulation Of Whole Cell Currents In Human Neuroblastoma Cells Via The Hormone Aldosterone: An In Vitro Study, Harish Kumar Chittam Mar 2016

Modulation Of Whole Cell Currents In Human Neuroblastoma Cells Via The Hormone Aldosterone: An In Vitro Study, Harish Kumar Chittam

Graduate Theses and Dissertations

Ion channels play a critical role in maintaining homeostasis by moving various ions in and out of cells. The Na+-K+-2Cl- or NKCC1 ion channel is involved in the regulation of Na+, K+, and Cl- across cell membranes, and plays a key role in many forms of cellular physiology. In the cochlea, NKCC1 is involved in endolymph production and maintenance of the endocochlear potential. Our hypothesis is that blocking NKCC1 channels should directly impact auditory sensitivity causing hearing loss. Our lab has also shown that the hormone aldosterone (ALD) can upregulate NKCC1 protein expression in vitro and in vivo ...


A Trans-Dimensional View Of Drug Resistance Evolution In Multiple Myeloma Patients, Timothy Jacobson Mar 2016

A Trans-Dimensional View Of Drug Resistance Evolution In Multiple Myeloma Patients, Timothy Jacobson

Graduate Theses and Dissertations

Multiple Myeloma (MM) is a treatable, yet incurable, malignancy of bone marrowplasma cells. This cancer affects many patients and many succumb to relapse of tumor burden despite a large number of available chemotherapeutic agents developed for therapy. This is because MM tumors are heterogeneous and receive protection from therapeutic agents by the microenvironment and other mechanisms including homologous MM-MM aggregation. Therefore, therapy failure and frequent patient relapse is due to the evolution of drug resistance, not a lack of available drugs. To analyze and understand this problem, the evolution of drug resistance has been explored and presented herein. We seek ...


Image-Based 3d Morphometric Analysis Of The Clavicle Intramedullary (Im) Canal, Jazmine Aira Mar 2016

Image-Based 3d Morphometric Analysis Of The Clavicle Intramedullary (Im) Canal, Jazmine Aira

Graduate Theses and Dissertations

Midshaft clavicle fractures are very common. Current treatment of choice involves internal fixation with superior or anterior clavicle plating, however their clinical success and patient satisfaction are slowly decreasing. The design of intramedullary (IM) devices is on the rise, but data describing the IM canal parameters is lacking. The aim of this study is to quantify morphometry of the clavicle and its IM canal, and to evaluate the effect of gender and anatomical side. This study used 3-dimensional (3D) image-based models with novel and automated methods of standardization, normalization and bone cross-section evaluation. The data obtained in this thesis presents ...


Regulatory Effect Of Elastin Based Biomaterial On Cellular Behavior And Its Application On Wound Repair And Regeneration, Yuan Yuan Mar 2016

Regulatory Effect Of Elastin Based Biomaterial On Cellular Behavior And Its Application On Wound Repair And Regeneration, Yuan Yuan

Graduate Theses and Dissertations

Elastin-like peptides (ELPs) are stimulus-responsive protein-based polymers which are attractive material for biomedical research due to their biocompatibility and unique properties. The physical properties of ELPs are dependent on the chain length and the chosen amino acid at the guest residue position. This imparts unlimited flexibility in designing ELP based biomaterials with the desired physical properties.

We have shown that in addition to their physical properties, ELPs have biological activities that are conducive to tissue regeneration. Specifically, we found that ELPs induce fibroblast proliferation via cell surface heparan sulfate proteoglycans (HSPG). Furthermore, our data suggests that ELP based materials with ...


Analysis And Processing Of Human Electroretinogram, Abdulrahman Mohammad Alaql Mar 2016

Analysis And Processing Of Human Electroretinogram, Abdulrahman Mohammad Alaql

Graduate Theses and Dissertations

Electroretinagram (ERG) is the recording of electrical activity of retinal cells elicited by light stimulation, which has been widely used to help diagnose different types of retinal dysfunctions. The ERG response signal is a short non-stationary signal that contains overlapping components. Different Digital Signal Processing (DSP) techniques are investigated using MATLAB to study the time-frequency responses of the ERG signal such as Short Time Fourier Transform (STFT), Continuous Wavelet Transform (CWT) and Discrete Wavelet Transform (DWT). The Photopic ERG signal was processed and analyzed in this thesis and the results of each technique have been investigated in detail. The Photopic ...


Selective Enhancement Of Macropinocytosis For The Treatment Of Non-Small Cell Lung Cancer, Raul Iglesias Mar 2016

Selective Enhancement Of Macropinocytosis For The Treatment Of Non-Small Cell Lung Cancer, Raul Iglesias

Graduate Theses and Dissertations

Over the past few years, researchers have focused their attention on the development of targeted cancer therapies to minimize the side effects associated with non-targeted treatments such as chemotherapy. Specifically, these approaches have focused on blocking growth factor receptors (GFR) that are overexpressed in cancer cells. In this thesis, we also focus on targeting overexpressed GFR; however, instead of blocking the GFR, our novel approach aims at using them to selectively enhance the endocytotic process of macropinocytosis to deliver peptides that either disrupts the mitochondria or inhibits glycolysis.

Herein, we show the selective enhancement of macropinocytosis by the fusion protein ...


Elastin Like Polypeptides As Drug Delivery Vehicles In Regenerative Medicine Applications, Alex Leonard Mar 2016

Elastin Like Polypeptides As Drug Delivery Vehicles In Regenerative Medicine Applications, Alex Leonard

Graduate Theses and Dissertations

Elastin like polypeptides (ELPs) are a class of naturally derived biomaterials that are non-immunogenic, genetically encodable, and biocompatible making them ideal for a variety of biomedical applications, ranging from drug delivery to tissue engineering. Also, ELPs undergo temperature-mediated inverse phase transitioning, which allows them to be purified in a relatively simple manner from bacterial expression hosts. Being able to genetically encode ELPs allows for the incorporation of bioactive peptides and functionalization of ELPs. This work utilizes ELPs for regenerative medicine and drug delivery.

The goal of the first study was to synthesize a biologically active epidermal growth factor-ELP (EGF-ELP) fusion ...