Engineering Commons^™

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

USF Tampa 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 …

Toward Translating Near-Infrared Spectroscopy Oxygen Saturation Data For The Non-Invasive Prediction Of Spatial And Temporal Hemodynamics During Exercise, Laura M. Ellwein, Margaret M. Samyn, Michael E. Danduran, Sheila M. Schindler-Ivens, Stacy Liebham, John F. Ladisa Jr.

Exercise Science Faculty Research and Publications

Image-based computational fluid dynamics (CFD) studies conducted at rest have shown that atherosclerotic plaque in the thoracic aorta (TA) correlates with adverse wall shear stress (WSS), but there is a paucity of such data under elevated flow conditions. We developed a pedaling exercise protocol to obtain phase contrast magnetic resonance imaging (PC-MRI) blood flow measurements in the TA and brachiocephalic arteries during three-tiered supine pedaling at 130, 150, and 170 % of resting heart rate (HR), and relate these measurements to non-invasive tissue oxygen saturation (StO₂) acquired by near-infrared spectroscopy (NIRS) while conducting the same protocol. Local quantification …

Automated Microscopy Platform For High-Throughput Analysis Of Cellular Characteristics, Hussam Ibrahim

Physics: Student Scholarship & Creative Works

Existing microscopy platforms allow analysis post-hoc, but not in real time. This is an issue in the world of Bioengineering because you are limited to performing further analysis on specimen. The aim of my research was to design a sophisticated system whereby information can be exchanged between the software which acquires images and software that analyzes the images immediately after acquisition. In this system, images would be acquired by the microscope and analyzed by customized scripts (MATLAB, Mathworks) in real time. Specifically, MATLAB would wait for new images to be saved on the hard drive, import these images, and perform …

Nano Clay-Enhanced Calcium Phosphate Cements And Hydrogels For Biomedical Applications, Udayabhanu Jammalamadaka

Doctoral Dissertations

Biomaterials are used as templates for drug delivery, scaffolds in tissue engineering, grafts in surgeries, and support for tissue regeneration. Novel biomaterial composites are needed to meet multifaceted requirements of compatibility, ease of fabrication and controlled drug delivery. Currently used biomaterials in orthopedics surgeries suffer limitations in toxicity and preventing infections. Polymethyl methacrylate (PMMA) used as bone cement suffers from limitations of thermal necrosis and monomer toxicity calls for development of better cementing biomaterials. A biodegradable/bioresorbable cement with good mechanical properties is needed to address this short coming. Metal implants used in fixing fractures or total joint replacement needs improvements …

Three-Dimensional Printing And Nanotechnology For Enhanced Implantable Materials, Karthik Kumar Tappa

Doctoral Dissertations

Orthopedic and oro-maxillofacial implants have revolutionized treatment of bone diseases and fractures. Currently available metallic implants have been in clinical use for more than 40 years and have proved medically efficacious. However, several drawbacks remain, such as excessive stiffness, accumulation of metal ions in surrounding tissue, growth restriction, required removal/revision surgery, inability to carry drugs, and susceptibility to infection. The need for additional revision surgery increases financial costs and prolongs recovery time for patients. These metallic implants are bulk manufactured and often do not meet patient's requirements. A surgeon must machine (cut, weld, trim or drill holes) them in order …

Hydrothermal Synthesis And Characterisation Of Bioactive Glass-Ceramic Nanorods, Ehsan Zeimaran, Sara Pourshahrestani, Seyed Farid Seyed Shirazi, Belinda Pingguan-Murphy, Nahrizul Adib Kadri, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study fabrication of rod-like bioactive glass-ceramics (BGCs) using hydrothermal treatment based on a sol-gel precursor is reported for the first time. BGCs with composition 58 wt% SiO₂, 33 wt% CaO and 9 wt% P₂O₅ were synthesized in different thermal conditions (200 and 220 °C) and characterised with regard to morphology, chemical composition and crystallinity. The bioactivity of the materials was assessed by immersion in simulated body fluid for up to 7 days. The results revealed that as the reaction temperature increased from 200 to 220 °C, the diameter of rods was reduced from …

Automated Measurement Of Fracture Callus In Radiographs Using Portable Software, Stephen M. Porter, Hannah L. Dailey, Katharine A. Hollar, Karina Klein, James A. Harty, Trevor J. Lujan

Mechanical and Biomedical Engineering Faculty Publications and Presentations

The development of software applications that assist the radiographic evaluation of fracture healing could advance clinical diagnosis and expedite the identification of effective treatment strategies. A radiographic feature regularly used as an outcome measure for basic and clinical fracture healing research is new bone growth, or fracture callus. In this study, we developed OrthoRead, a portable software application that uses image-processing algorithms to detect and measure fracture callus in plain radiographs. OrthoRead utilizes an optimal boundary tracking algorithm to semi-automatically segment the cortical surface, and a novel iterative thresholding selection algorithm to then automatically segment the fracture callus. The software …

Fabrication, Characterization And Skin Permeation Of Antoxidant-Loaded Lipid Vesicles For Transdermal Drug Delivery., Emily Martin

Electronic Theses and Dissertations

Excess production of Reactive Oxygen Species (ROS), which can be caused by radiation, cigarette smoke, and pollutants, can cause many damaging cellular effects, such as DNA damage and unregulated cell apoptosis. If left unmitigated, chronic overproduction of ROS has been linked to the formation of cancer, diabetes, atherosclerosis, rheumatoid arthritis, chronic inflammation, Parkinson’s disease, Alzheimer’s disease, multiple sclerosis, and amyotrophic lateral sclerosis. ROS is typically eliminated with antioxidants, which scavenge and inhibit the formation of ROS by becoming oxidized by the ROS and by binding to its precursors.

Curcumin is an effective lipid-soluble antioxidant agent. However, its poor bioavailability, rapid …

Development And Evaluation Of Custom Prosthetic Devices For A Companion Animal Utilizing Additive Manufacturing., Benjamin Joseph Cahill

Electronic Theses and Dissertations

BACKGROUND AND SIGINIFICANCE: Few options exist for companion animals in need of prosthetic devices. With the rise of rapid prototyping technology, the availability and customization of prosthetic devices for individual companion animals is now a viable and cost effective alternative to the current options of a peg leg prosthetic, or wheel-assisted prosthetic device. The goals of this study were to describe the (1) specific needs and (2) biomechanics of a feline with bilateral thoracic limb amputation, (3) develop custom prosthetic devices utilizing rapid prototyping technology, and (4) describe the biomechanics of a feline with bilateral thoracic limb amputation using the …

Engineering Xylose Utilization In Yarrowia Lipolytica By Understanding Its Cryptic Xylose Pathway, Gabriel M. Rodriguez, Murtaza Shabbir Hussain, Lauren Gambill, Difeng Gao, Allison Yaguchi, Mark Blenner

Publications

Background

The oleaginous yeast, Yarrowia lipolytica, has been utilized as an industrial host for about 60 years for various applications. Recently, the metabolic engineering of this host has become increasingly popular due to its ability to accumulate lipids as well as improvements made toward developing new genetic tools. Y. lipolytica can robustly metabolize glucose, glycerol, and even different lipid classes. However, little is known about its xylose metabolizing capability. Given the desirability of having a robust xylose utilizing strain of Y. lipolytica, we performed a comprehensive investigation and elucidation of the existing components of its xylose metabolic pathway. …

Deposition Of Carbon Nanotube Films On Polyamide And Polypropylene Substrates: A Computer Simulation Approach, Alejandro Heredia, Maria Colin-Garcia, Maria Del Pilar Carreon-Castro, Debarati Mukherjee, Bruno Abreu, David William Britt, Joana Catarina Mendes

Biological Engineering Faculty Publications

In this work we study hydroxylated carbon nanotube (CNT) assembly on polyamide (PA) and polypropylene (PP) polymers activated by UV radiation from a theoretical and experimental perspective. Molecular computer simulation was done to understand the stable conformations and bulk properties (molecular dynamics) of the polymers before and after exposure to UV radiation at the molecular level. Our experiments suggest that PA presents more -OH active groups, producing a more hydrophilic surface, whereas PP exhibits less potential UV activation. These results suggest that it is possible a facile covalent functionalization method to tune organic polymer surface properties through SWCNT anchoring for …

Co-Ops And Capstone Design: Are They Interchangeable?, Jay R. Goldberg

Biomedical Engineering Faculty Research and Publications

Many engineering schools in the United States provide opportunities for their undergraduate students to gain practical, real-world experience in their chosen disciplines. Cooperative education is a structured method of combining classroom-based education with practical work experience. A cooperative education experience, commonly known as a co-op, provides academic credit (and pay) for such an experience. Discusses the benefits of these working experiences, focusing on capstone design courses.

Attenuation Of The Ganglion Cell Layer In A Premature Infant Revealed With Handheld Spectral Domain Optical Coherence Tomography, Mara R. Goldberg, Fouad R. Zakka, Joseph Carroll, Deborah M. Costakos

Biomedical Engineering Faculty Research and Publications

Purpose: To report on subclinical retinal abnormalities shown through handheld spectral domain optical coherence tomography on a premature infant.

Methods: Case report.

Results: The initial and follow-up exams on a premature infant revealed severely attenuated ganglion cell and nerve fiber layers. There was cystoid macular edema in both eyes at the initial visits, which resolved by the 1-year follow-up.

Discussion: Optical coherence tomography can reveal significant retinal abnormalities in premature infants which are not detectable through funduscopic exam. Documenting such findings may be useful for the comprehensive management of vision problems in children with a history of premature birth.

Machine Learning Methods For Medical And Biological Image Computing, Rongjian Li

Computer Science Theses & Dissertations

Medical and biological imaging technologies provide valuable visualization information of structure and function for an organ from the level of individual molecules to the whole object. Brain is the most complex organ in body, and it increasingly attracts intense research attentions with the rapid development of medical and bio-logical imaging technologies. A massive amount of high-dimensional brain imaging data being generated makes the design of computational methods for efficient analysis on those images highly demanded. The current study of computational methods using hand-crafted features does not scale with the increasing number of brain images, hindering the pace of scientific discoveries …

Microbubble Generation By Piezoelectric Transducers For Biomedical Studies, Mohammed Alkhazal

Electrical & Computer Engineering Theses & Dissertations

Bubbles induced by blast waves or shocks are speculated as the major cause of damage in biological cells in mild traumatic brain injuries (TBI). Microbubble collapse was found to induce noticeable cell detachment from the cell substrate, changes in focal adhesion, and biomechanics. To better understand the bubble mechanism, a system needs to be constructed which allows clear differentiation on the impact of bubbles from that of shocks. Such a generator needs to be low profile in order to place under a microscope. A piezoelectric transducer system was designed to meet the need. The system uses either a flat or …

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

USF Tampa 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.

Functional Comparison Of Conventional Afos With The Dynamic Response Afo, Mitchell Ruble

Master's Theses (2009 -)

Ankle foot orthoses (AFOs) are commonly prescribed to provide stability and foot clearance for patients with weakened or injured musculature. The Dynamic Response AFO (DRAFO) was designed to improve proprioception at heel strike. The design includes a rigid outer shell with a cut out heel and a soft inner lining; it is typically aligned in plantarflexion and may incorporate external heel wedges. The objective of this study was to investigate the effects of the DRAFO design features and contrast its biomechanical function with that of conventional locked and articulating AFOs. The research hypotheses were: 1) DRAFO-assisted gait parameters (e.g. ankle …

Enabling Studies To Optimize Biomaterials For The Treatment Of Myocardial Infarction, Eva Adriana Romito

Theses and Dissertations

The canonical mechanism of wound healing is disrupted following a myocardial infarction (MI), manifesting as an unregulated response that negatively impacts left ventricular (LV) function. This mechanism, termed post-MI remodeling, culminates in an outcome that favors progression to a systolic heart failure state and death for the patient. Therapeutic approaches following the occurrence of a MI are designed to modulate the natural remodeling process and mitigate the loss of cardiac function. The mechanics and structure of the healing infarct have been the focus of numerous pre-clinical and clinical investigations, leading to the impending clinical introduction of material injections as a …

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

USF Tampa 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 …

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

USF Tampa 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 of …

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

USF Tampa 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 …

Hydrothermally Processed 1d Hydroxyapatite: Mechanism Of Formation And Biocompatibility Studies, Zoran Stojanović, Nenad Ignjatović, Victoria M. Wu, Vojca Žunič, Ljiljana Veselinović, Srečo D. Škapin, Miroslav Miljković, Vuk Uskoković, Dragab Uskoković

Pharmacy Faculty Articles and Research

Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome …

Intracranial Pressure Sensor, Matthew Murray, Jared Shimada

Bioengineering Senior Theses

Idiopathic Intracranial Hypertension (IIH) also known as Pseudotumor Cerebri is a condition resulting from an increase of Cerebrospinal Fluid (CSF), a fluid that helps to protect the brain and spinal cord, in the cranial cavity. Currently the only treatment method for this health condition is the draining of the fluid via implanted intracranial shunts that get clogged in approximately 50% of patients. Clogged shunts can only be detected when IIH symptoms begin to reappear. We propose to create an ultrasound-read intracranial pressure sensor used to supplement shunts implanted in patients who suffer from Idiopathic Intracranial Hypertension. This will provide immediate …

Enhancing Student Usability Of 3d Bioprinting, Andrew Chang, Sabrina Cismas

Interdisciplinary Design Senior Theses

3D bioprinting is an emerging technology that is changing the face of tissue engineering through the ability to print cells, scaffolding and matrix materials, and other bioactive reagents. 3D bioprinters are a culmination of various scientific and engineering disciplines with respect to their operation and bioprints, and as such, offer a prime case study on the convergence of the technical fields in research. In order to capitalize on this fact and make 3D bioprinting more accessible for interdisciplinary education applications, we sought to translate 3D bioprinting into the classroom environment as a tool for education. In collaboration with SE3D Education, …

Bolstering The Cell Membrane Of S. Cerevisiae For Efficient Bioethanol Production From Lignocellulosic Biomass, Conary Meyer, Matt Kubit

Bioengineering Senior Theses

With the need for alternatives to fossil fuels becoming more prevalent, biofuels has become an increasingly attractive alternative. Traditional biofuel production was quickly halted as a result of its ethical complications, leading to the development of secondgeneration biofuels. This system utilizes plant waste instead of food as its starting material, allowing for rapid recycling of this widely available and cheap carbon source. This switch was, however, coupled with complications. Of those, the most prominent is the inevitable release of acetic acid resulting from the breakdown of the lignocellulosic waste. This acetic acid is challenging to neutralize or extract in a …

Preclinical Study For Targeted Breast Cancer Therapy, Katie Bond, Lauren Mccormick, Jordan Karroll

Bioengineering Senior Theses

Cancer is a devastating disease which affects millions. For this reason, many scientists are working to develop drugs that can specifically target cancer cells within the body. Preclinical trials are an important phase in the drug development process, as they allow scientists to determine whether or not a drug candidate may be viable for human use. Targeted therapies can be achieved by using monoclonal antibodies as well as small molecule drugs. In this study we compared the effects of two control monoclonal antibody drugs, “mAb1” and “mAb2,” with one small molecule drug, “Drug S,” on the MDAMB231 human breast cancer …

Suture Passing Device For Hyoid Susupension In Sleep Apnea Surgery, Corbin Craven, Nicholas Leavengood, Solomon Mulugeta

Bioengineering Senior Theses

Obstructive Sleep Apnea (OSA) is a condition which is characterized by momentary pauses in a person’s breathing while they are sleeping. Current treatment options for sleep apnea include CPAP, oral appliances, and surgery. Of these options, hyoid suspension surgery is one of the most effective, but is significantly underutilized. This is due to the fact that performing hyoid suspension surgery by current methods is complicated and can be painful for the patient. As our senior design project, we designed and prototyped a novel medical device that facilitates fast, easy, and consistent hyoid suspension surgery. Through functional testing of our device …

Microfluidic Detection Of Biogenic Amines, Trenton Nagasawa, Partha Vora, Nnaoma Agwu, Joshua Tan

Bioengineering Senior Theses

For our study of Microfluidic Detection of Biogenic Amines, we have designed a microfluidic device to separate and detect different biogenic amine concentrations using amperometric detection. The goal of this project is to identify and quantify biogenic amines form the neural fluid extracted from the pericardial cavity of the Jonah crabs (Cancer Borealis). The device that we designed utilizes polydimethylsiloxane (commonly known as PDMS) along with a carbon paste electrode and a palladium decoupler. Using capillary electrophoresis (CE) along with amperometric detection, we aim to separate biogenic amines and detect them with amperometric detection.

Innovations In Traumatic Hemorrhage, Joseph Anthony Ikaika Choy, Nicholas Domek, John “Patrick” Tavelli

Bioengineering Senior Theses

Traumatic hemorrhagic injuries present a great problem to humanity and a challenge to medicine in the modern world. Current methods of treating these injuries in the field are ineffective and often extremely overkill or injurious. These methods are particularly inadequate when applied to the continuous high pressure bleeding that occurs from arterial wounds. Our project focuses on lowering the barriers to entry to innovation in the field of bleeding treatment by creating a low cost model of the human circulatory system. This model can function as a low-cost testing platform for novel bleeding treatments developed by companies and individuals that …

Design And Validate A Synthetic Circuit For Detecting Pathway Signaling In Mammalian Cells, Darisha Jhutty, Nicholas Parker

Bioengineering Senior Theses

Synthetic circuits provide novel ways for scientists to program and probe mammalian cell behavior. This allows for enhanced research tools and chemical sensors. Our project works with an engineered synthetic circuit and monitors the output of the circuit using green fluorescent protein( GFP) and luciferase. Expression of GFP is both quantifiable and observable over a time period in living cells. Luciferase can be detected by an assay in lysed cells to give data on overall expression of the circuit. By measuring and comparing output of this circuit over time, we can create a model to demonstrate the lack of expression, …