Biomedical Engineering and Bioengineering Commons^™

The Development Of A Novel Polymer Based System For Gene Delivery, Anh Van Le

FIU Electronic Theses and Dissertations

Gene therapy involves the use of nucleic acids, either DNA or RNA for the treatment, cure, or prevention of human diseases. Synthetic cationic polymers are promising as a tool for gene delivery because of their high level of design flexibility for biomaterial construction and are capable of binding and condensing DNA through electrostatic interactions.

Our lab has developed a novel polymer (poly (polyethylene glycol-dodecanoate) (PEGD), a polyester of polyethylene glycol (PEG) and dodecanedioic acid (DDA). PEGD is a linear viscous polymer that self-assembles into a vesicle upon immersion in an aqueous solution. A copolymer of dodecanedioc acid and polyethylene glycol …

Cobalt Ferrite Nanoparticles Fabricated Via Co-Precipitation In Air: Overview Of Size Control And Magnetic Properties, Dennis Toledo

FIU Electronic Theses and Dissertations

Cobalt Ferrite has important, size-dependent magnetic properties. Consequently, an overview of particle size is important. Co-precipitation in air was the fabrication method used because it is comparatively simple and safe. The effects of three different reaction times including 1, 2, 3 hour(s) on particle size were compared. Also, the effectiveness of three different capping agents (Oleic Acid, Polyvinylpyrollidone (PVP), and Trisodium Citrate) in reducing aggregation and correspondingly particle size were examined. Using Welch’s analysis of variance (ANOVA) and the relevant post hoc tests, there was no significant difference (p=0.05) between reaction times of 1 hour and 2 hours, but there …

Enhanced Flexible Materials For Valve Prosthesis Applications, Makensley Lordeus

FIU Electronic Theses and Dissertations

While mechanical, homograft and bio-prosthetic valves have been used in patients for many decades and have made significant improvements in patient morbidity, there is still a distinct need to overcome their limitations. Recently, emerging elastomer heart valves have been shown to be able to better re-create the flow physics of native heart valves, resulting in preferable hemodynamic responses. Unfortunately, elastomers such as silicone are prone to structural failure, which drastically limits their applicability towards the development of valve prosthesis. In order to produce a mechanically more robust silicone substrate, we reinforced it with graphene nanoplatelets (GNPs). Cytotoxicity and hemocompatibility tests …

Histological Characterization Of Inter Ictal Epileptiform Discharges Generating Brain Regions Using A Preclinical Model Of Focal Cortical Dysplasia, Abhay S. Deshmukh

FIU Electronic Theses and Dissertations

Current clinical practice of resective surgery in focal epilepsy involves electroencephalogram (EEG) brain source imaging to localize irritative brain areas from where Inter-ictal epileptiform discharges (IEDs) emerge, useful to localize the seizures-onset zones. Unfortunately, there are no previous systematic studies to characterize the pathophysiological mechanisms and abnormal cellular substrates in these irritative areas since histological data are available only from the final resective zones. To address this issue we applied a combination of EEG brain imaging described by Bae et al. (2015) using cutting-edge technology for high-density scalp EEG in rodents and histological analysis on a chronic rat model of …

Cellular Events Under Flow States Pertinent To Heart Valve Function, Glenda L. Castellanos

FIU Electronic Theses and Dissertations

Heart valve disease (HVD) or a damaged valve can severely compromise the heart's ability to pump efficiently. Balloon valvuloplasty is preferred on neonates with aortic valve stenosis. Even though this procedure decreases the gradient pressure across the aortic valve, restenosis is observed soon after balloon intervention. Tissue engineering heart valves (TEHV), using bone marrow stem cells (BMSCs) and biodegradable scaffolds, have been investigated as an alternative to current non-viable prosthesis. By observing the changes in hemodynamics following balloon aortic valvuloplasty, we could uncover a potential cause for rapid restenosis after balloon intervention. Subsequently, a tissue engineering treatment strategy based on …

Lectin Staining And Western Blot Data Showing Differential Sialylation Of Nutrient-Deprived Cancer Cells To Sialic Acid Supplementation, Haitham A. Badr, Dina M.M. Alsadek, Mohit P. Mathew, Chen-Zhong Li, Leyla B. Djansugurova, Kevin J. Yarema, Hafiz Ahmed

Department of Biomedical Engineering Faculty Publications

No abstract provided.

Label-Free Surface-Enhanced Raman Spectroscopy-Linked Immunosensor Assay (Slisa) For Environmental Surveillance, Vinay Bhardwaj

FIU Electronic Theses and Dissertations

The contamination of the environment, accidental or intentional, in particular with chemical toxins such as industrial chemicals and chemical warfare agents has increased public fear. There is a critical requirement for the continuous detection of toxins present at very low levels in the environment. Indeed, some ultra-sensitive analytical techniques already exist, for example chromatography and mass spectroscopy, which are approved by the US Environmental Protection Agency for the detection of toxins. However, these techniques are limited to the detection of known toxins. Cellular expression of genomic and proteomic biomarkers in response to toxins allows monitoring of known as well as …

Multifunctional Nanoparticles For Theranostic Applications, Supriya Srinivasan

FIU Electronic Theses and Dissertations

Multifunctional agents for the management of highly heterogeneous diseases, like cancer, are gaining increased interest with the intent of improving the diagnostics and therapy of cancer patients. These agents are also important because more than one treatment modality is typically used for cancer therapy in the clinic. Further, nanotechnology offers a platform where more than one agent can be combined to help provide improved cancer diagnosis and therapy. Near-infrared light-activatable phototherapeutic agents have great potential in vivo. Body tissues have minimum absorption in the near- infrared range. They also have been shown to enhance the cytotoxic effect of chemotherapeutic …

Intraoperative Guidance For Pediatric Brain Surgery Based On Optical Techniques, Yinchen Song

FIU Electronic Theses and Dissertations

For most of the patients with brain tumors and/or epilepsy, surgical resection of brain lesions, when applicable, remains one of the optimal treatment options. The success of the surgery hinges on accurate demarcation of neoplastic and epileptogenic brain tissue. The primary goal of this PhD dissertation is to demonstrate the feasibility of using various optical techniques in conjunction with sophisticated signal processing algorithms to differentiate brain tumor and epileptogenic cortex from normal brain tissue intraoperatively.

In this dissertation, a new tissue differentiation algorithm was developed to detect brain tumors in vivo using a probe-based diffuse reflectance spectroscopy system. The system …

The Microstructure And The Electrochemical Behavior Of Cobalt Chromium Molybdenum Alloys From Retrieved Hip Implants, Christopher P. Emerson

FIU Electronic Theses and Dissertations

Because of their excellent mechanical, tribological, and electrochemical properties, Cobalt Chromium Molybdenum alloys have been used as the material for both the stem and head of modular hip implants. Corrosion is one mechanism by which metal debris, from these implants, is generated, which can lead to adverse events that requires revision surgery. Manufacturing process such as wrought, as-cast, and powder metallurgy influences the microstructure, material properties, and performance of these implants

The current research focuses on analyzing the microstructure of CoCrMo alloys from retrieved hip implants with optical and scanning electron microscopy. Additionally, energy disperse spectroscopy was utilized to determine …

Development Of Point-Of-Care Testing Sensors For Biomarker Detection, Xuena Zhu

FIU Electronic Theses and Dissertations

Point-of-care testing (POCT) is defined as medical testing at or near the site of patient care and has become a critical component of the diagnostic industry. POCT has many advantages over tests in centralized laboratories including small reagent volumes, small size, rapid turnaround time, cost-effectiveness, low power consumption and functional integration of multiple devices. Paper-based POCT sensors are a new alternative technology for fabricating simple, low-cost, portable and disposable analytical devices for clinical diagnosis.

The focus of this dissertation was to develop simple, rapid and low cost paper-based POCT sensors with high sensitivity and portability for disease biomarker detection. Lateral …

In-Vivo Corrosion And Fretting Of Modular Ti-6al-4v/Co-Cr-Mo Hip Prostheses: The Influence Of Microstructure And Design Parameters, Jose Luis Gonzalez Jr

FIU Electronic Theses and Dissertations

The purpose of this study was to evaluate the incidence of corrosion and fretting in 48 retrieved titanium-6aluminum-4vanadium and/or cobalt-chromium-molybdenum modular total hip prosthesis with respect to alloy material microstructure and design parameters. The results revealed vastly different performance results for the wide array of microstructures examined. Severe corrosion/fretting was seen in 100% of as-cast, 24% of low carbon wrought, 9% of high carbon wrought and 5% of solution heat treated cobalt-chrome. Severe corrosion/fretting was observed in 60% of Ti-6Al-4V components. Design features which allow for fluid entry and stagnation, amplification of contact pressure and/or increased micromotion were also shown …

Fiber Scaffolds Of Poly (Glycerol-Dodecanedioate) And Its Derivative Via Electrospinning For Neural Tissue Engineering, Xizi Dai

FIU Electronic Theses and Dissertations

Peripheral nerves have demonstrated the ability to bridge gaps of up to 6 mm. Peripheral Nerve System injury sites beyond this range need autograft or allograft surgery. Central Nerve System cells do not allow spontaneous regeneration due to the intrinsic environmental inhibition. Although stem cell therapy seems to be a promising approach towards nerve repair, it is essential to use the distinct three-dimensional architecture of a cell scaffold with proper biomolecule embedding in order to ensure that the local environment can be controlled well enough for growth and survival. Many approaches have been developed for the fabrication of 3D scaffolds, …

Regulation Of Bone Marrow Stem Cells Through Oscillatory Shear Stresses - A Heart Valve Tissue Engineering Perspective, Sasmita Rath

FIU Electronic Theses and Dissertations

Heart valve disease occurs in adults as well as in pediatric population due to age-related changes, rheumatic fever, infection or congenital condition. Current treatment options are limited to mechanical heart valve (MHV) or bio-prosthetic heart valve (BHV) replacements. Lifelong anti-coagulant medication in case of MHV and calcification, durability in case of BHV are major setbacks for both treatments. Lack of somatic growth of these implants require multiple surgical interventions in case of pediatric patients. Advent of stem cell research and regenerative therapy propose an alternative and potential tissue engineered heart valves (TEHV) treatment approach to treat this life threatening condition. …

Novel In-Vitro Epilepsy Ipsc Model, Anthony Giordano

Undergraduate Research at FIU (URFIU) Conference

The main focus of this ARCH research project is to create a novel in-vitro epilepsy model will using iPSC techniques. Neural tissue will be collected from both epileptic and control rats and then the neural tissue will be induced to pluripotent stem cells and regrown in a petri dish. It has been hypothesized that the regrown stem cells will have the same genetic characteristics as the host cells they come from. To confirm this both Western Blot and RTPCR will be performed on both the host tissue and the newly grown astrocytes and neurons (of both epileptic and control rats) …

Mass Spectrometric Lipidomic Analyses Of Human Aqueous Humor, Catalina Garzon

Undergraduate Research at FIU (URFIU) Conference

Primary Open Angle Glaucoma, the leading cause for peripheral blindness in the United States, has an etiology not completely understood but highly related to elevated levels of intraocular pressure. Presumably, the plasma membrane, mainly composed of phospholipids, of the cells experience imperative structural and functional changes during the glaucoma neuropathy. Previous studies were unable to adequately investigate ocular lipidomics because of low lipid yield and sub-par identification and quantification methods until the recent advent of mass spectrometry. The objective of the project is to understand how to use mass spectrometry to characterize 4 classes of phospholipids in terms of quantity …

Systematic Monitoring Of Wound Healing Using A Hand-Held Near-Infrared Optical Scanner, Stephanie Gonzalez, Elizabeth Solis, Suset Rodriguez

Undergraduate Research at FIU (URFIU) Conference

According to the American Podiatric Medical Association, about 15 percent of the patients with diabetes would develop a diabetic foot ulcer. Furthermore, foot ulcerations leads to 85 percent of the diabetes-related amputations. Foot ulcers are caused due to a combination of factors, such as lack of feeling in the foot, poor circulation, foot deformities and the duration of the diabetes. To date, the wounds are inspected visually to monitor the wound healing, without any objective imaging approach to look before the wound’s surface. Herein, a non-contact, portable handheld optical device was developed at the Optical Imaging Laboratory as an objective …

Theoretical Investigation Of Intra- And Inter-Cellular Spatiotemporal Calcium Patterns In Microcirculation, Jaimit B. Parikh

FIU Electronic Theses and Dissertations

Microcirculatory vessels are lined by endothelial cells (ECs) which are surrounded by a single or multiple layer of smooth muscle cells (SMCs). Spontaneous and agonist induced spatiotemporal calcium (Ca²⁺) events are generated in ECs and SMCs, and regulated by complex bi-directional signaling between the two layers which ultimately determines the vessel tone. The contractile state of microcirculatory vessels is an important factor in the determination of vascular resistance, blood flow and blood pressure. This dissertation presents theoretical insights into some of the important and currently unresolved phenomena in microvascular tone regulation. Compartmental and continuum models of isolated EC …