Biomedical and Dental Materials Commons^™

Biomedical Applications Of Protein Films And Polymeric Nanomaterials, Sanjana Gopalakrishnan

Doctoral Dissertations

Biomaterials are widely applied for the diagnosis and treatment of numerous diseases. In addition to fulfilling specific biological functions, biomaterials must also be non-toxic, biocompatible, and sterilizable to be regarded as safe-for-use. Polymers are excellent candidates for fabricating functional biomaterials due to their wide availability and varied properties and may be natural or synthetic. Polymer precursors are fabricated into coatings, foams, scaffolds, gels, composites, and nanomaterials for several biomedical applications. This dissertation focuses on two types of polymeric biomaterials – protein-based materials and synthetic polymeric nanoparticles. Proteins are biopolymers that naturally occur with a variety of structural and functional properties. …

Electrochemical Deposition Of Calcium Phosphate-Based Coatings Onto Porous Ti Using Organic Phosphorus Sources, Clement Lee

Electronic Thesis and Dissertation Repository

The study and commercialization of calcium phosphate (Ca-P) coatings has occurred for several decades. However, this has typically involved the use of hydroxyapatite. This thesis presents the synthesis of different Ca-P-based coatings that has not been studied. Anodic oxidation was employed to create a porous Ti substrate, while pulsed electrochemical deposition was used to deposit the coating onto the Ti. The first coating synthesized was a calcium phosphoserine (Ca-pSer) complex, which contained two different morphologies: a flower-like structure at low deposition time and a unique cubic morphology at higher deposition times. Next, an amorphous calcium phosphate coating was synthesized and …

Safety Of Silver Oxide Coated Biomaterials In Mice, Michael Klug, Darien L. Seidman, Rahyan Mahmoud, Destiny Morot, Lei Yu, Jeffrey D Hettinger, Renee M Demarest

Stratford Campus Research Day

It has been demonstrated that silver oxide coatings designed by our collaborators are able to prevent E. coli and P. aeruginosa attachment to biomaterials in vivo. These findings demonstrate that such coatings show promise in preventing the development of biofilm on biodevices. However, it is unknown if the use of silver oxide in this fashion is toxic in vivo. The goal of this project was to determine whether our silver oxide coatings are safe to use in vivo. To assess the toxicity of our silver oxide formula, mice were implanted with either silver oxide coated titanium discs or uncoated titanium …

Assessment Of The Use Of Low Molecular Weight Diblock Copolymers For The Formation Of Stable, Tunable Droplet Interface Bilayers, Joseph Tawfik

Masters Theses

This thesis presents the use of diblock copolymers, poly(butadiene)-b-poly(ethylene oxide) (PB_m PEO_n) and poly(isoprene)-b-poly(ethylene oxide) (PI_mPEO_n), as amphiphilic molecular building blocks for the formation of synthetic polymer bilayer membranes using the droplet interface bilayer (DIB) technique. The DIB technique makes use of the self-assembly of amphiphilic macromolecules along oil-water droplet interfaces that can then be physically connected for the construction of liquid supported macromolecular bilayers at the droplet interface. These bilayer membranes are capable of hosting both naturally occurring and synthetic protein channels. This technique has been used to form synthetic bilayer membranes …

I. Non-Degradable Polysiloxane Networks For Controlled Release Applications, And Ii. Additive Free, Degradable Silyl-Ether Furyl-Maleimide Networks, Caleb M. Bunton

Chemistry Theses and Dissertations

I. Two different series of non–degradable polysiloxane networks were prepared for the encapsulation and controlled release of a small molecule agent. For the first series, hydrosilylation was utilized to prepare networks of varying crosslink densities, as determined from swelling studies, from vinyl terminated and silylhydride functional poly(dimethyl)siloxanes. For the second series, the thiol-ene reaction was utilized to prepare networks of varying crosslink densities, as determined from swelling studies, from vinyl terminated and mercaptopropyl functional poly(dimethyl)siloxanes. Nile red dye was used as an encapsulated agent and dye release from each series of networks was measured using UV–vis spectroscopy to determine controllability …

Protein Detection And Structural Characterization By Mass Spectrometry Using Supramolecular Assemblies And Small Molecules, Bo Zhao

Doctoral Dissertations

Mass spectrometry (MS) has played an increasingly prominent role in proteomics and structure biology because it shows superior capabilities in identification, quantification and structural characterization of proteins. To realize its full potential in protein analysis, significant progress has been made in developing innovative techniques and reagents that can couple to MS detection. This dissertation demonstrates the use of polymeric supramolecular assemblies for enhanced protein detection in complex biological mixtures by MS. An amphiphilic random co-polymer scaffold is developed to form functional supramolecular assemblies for protein/ peptide enrichment. The influences of charge density and functional group pK_a on host-guest interactions …

Developing A Dissociative Nanocontainer For Peptide Drug Delivery, Michael Patrick Kelly

Dissertations, Theses, and Capstone Projects

The potency and specificity of bioactive peptides have propelled these agents to the forefront of pharmacological research. However, delivery of peptides to their molecular target in cells is a major obstacle to their widespread application. A Trojan Horse strategy of packaging a bioactive peptide within a modified protein cage to protect it during transport, and releasing it at the target site, is a promising delivery method. Recent work has demonstrated that the viral capsid of the P22 bacteriophage can be loaded with an arbitrary, genetically-encoded peptide, and externally decorated with a cell-penetrating peptide, such as HIV-Tat, to translocate across in …

Effect Of Histatin- And Statherin-Derived Engineered Salivary Peptides On Streptococcus Mutans Adhesion And On Enamel Demineralization Provoked By Cariogenic Biofilms, Lina Maria Marin

Electronic Thesis and Dissertation Repository

Dental biofilm is formed onto dental surfaces covered by a layer of specific salivary proteins and peptides named acquired enamel pellicle (AEP). It was previously demonstrated that the statherin- and histatin-derived engineered salivary peptides DR9-DR9 and DR9-RR14 were able to reduce enamel demineralization and displayed antimicrobial activity against Streptococcus mutans, respectively. However, these studies were carried under experimental conditions that did not mimic caries development induced by biofilm and sucrose exposure, the most cariogenic dietary sugar. In this thesis we assessed the effect of the engineered salivary peptides on 1) the adherence of S. mutans to hydroxyapatite (HAp), and …

Distribution And Localization Of Novel Iodine Nanoparticles In The Human Glioma 1242 Growing In The Brains Of Mice, Benjamin Billings

Honors Scholar Theses

Observing and designing the in vivo distribution and localization of therapeutic nanoparticles is an essential aspect of developing and understanding novel nanoparticle- based medical treatments. This study investigates novel PEGylated Iodine-based nanoparticles (INPs), an alternate composition to the more widely researched gold nanoparticles (AuNPs), which may help avoid adverse effects associated with AuNPs, such as potential toxicity and skin discoloration, when used in similar applications. Determining the localization of the novel INPs within murine brains containing human glioma U-1242MG cells is critical in assisting the development of radiation dose enhancement therapy for this aggressive cancer. Radiation dose enhancement utilizes the …

Exploring Alternative Therapeutic Interventions For The Treatment Of Leigh Syndrome, Stephanie Martin

Theses and Dissertations

Leigh syndrome is the most common mitochondrial disease, affecting 1:40,000 live births. It manifests with symptoms including ataxia, cognitive impairment, motor difficulties, and stroke. Leigh syndrome is a genetic condition caused by mutations in either the nuclear DNA or mitochondrial DNA that affects the assembly of the electron transport chains. Death typically occurs around 2-3 years of age, due to respiratory failure, as the body cannot produce sufficient ATP for survival. The genetic basis of Leigh syndrome means that there is no cure, and current treatments of the symptoms have proven ineffective. This thesis proposes two different therapeutic approaches for …

Characterization Of Tetraethyl Orthosilicate-Based Dynamic Hydrogels For Use As Reversible 3-D Cell Culture Matrices, Krisitan Stipe

Graduate Student Theses, Dissertations, & Professional Papers

No abstract provided.

Functionalizing Titanium Implants With Bioactive Peptides To Increase Osseointegration, Neil Bernard

Williams Honors College, Honors Research Projects

Orthopedic surgeries have continued to increase, but the material of choice remains constant: titanium. Titanium has become the benchmark implant material due to its durability and non-immunogenic properties. However, while high rates of success are correlated with joint replacement surgery, certain patients with predisposed diseases such as diabetes or arthritis may have increased complications.¹ This can be due to lack of osseointegration due to decreased bone formation and mineralization,² which will lead to increased rates of infection or aseptic loosening of the implant from the bone. ³ Current methods to alleviate these complications include invasive revisional surgeries, which …

Regulation Of Prostaglandin D2 And Angiogenesis-Related Factors From Human Skin Mast Cells By Interleukin-6 And Resveratrol, Cody Cody Mchale

Theses and Dissertations

Mast cells are classically recognized as the effector cells of Immunoglobulin E (IgE)-mediated hypersensitivity reactions (i.e. allergic reactions). Mast cells also play an important role in the innate immune response to parasitic helminth infection. Allergic disease including allergic rhinitis, asthma, atopic dermatitis, and anaphylaxis, is a major health concern in the United States with greater than 60 million Americans suffering from allergy and asthma. In addition, mast cells have more recently been implicated in non-allergic disease including various human cancers, which will affect approximately 39.6% of U.S. men and women. Therefore, understanding the immunological and molecular mechanisms that regulate mast …

Operation Of The Leica Sp8 Multiphoton Confocal System Using Single Or Multiple Fluorochromes, Amy E. Rowley

Theses and Dissertations

The goal of this thesis is to systematically examine each decision made in obtaining images on the Leica SP8 Multiphoton Confocal Microscope and discuss the basic operating parameters in order to generate publication quality images. The capabilities of the LAS X software are discussed along with an in depth discussion of each icon in order, beginning with the Configuration icon, moving then to Acquire, and a brief overview of the possible imaging processing functions within the Process icon. At the conclusion of this thesis, the reader should feel comfortable with the operation of a confocal system and understand the tradeoffs …

The Role Of Cyclin-Dependent Kinase 8 In Vascular Disease, Desiree Leach

Theses and Dissertations

In response to injury, mature vascular smooth muscle cells (SMCs) undergo dedifferentiation, also known as phenotype modulation or switch. This process is characterized by a downregulation or loss of expression of contractile genes and concomitant with an increase in cell proliferation, migration, and extracellular matrix production, thereby leading to vascular lesion formation. However, the underlying molecular mechanism is not fully understood. The objective of my study was to determine whether cyclin-dependent kinase 8 (CDK8), a transcription-regulating kinase, plays a mediator role in vascular SMC dedifferentiation and lesion formation. Our results from immunochemical staining and Western blot revealed that CDK8 expression …

Antimicrobial Hydroxyapatite-Gelatin-Silica Composite Pastes With Tunable Setting Properties, Vuk Uskoković, Shreya Ghosh, Victoria M. Wu

Pharmacy Faculty Articles and Research

Bone grafting is one of the commonest surgical procedures, yet all bone substitutes developed so far suffer from specific weaknesses and the search for a bone graft material with ideal physical and biological properties is still ongoing. Calcium phosphate pastes are the most frequently used synthetic bone grafts, yet they (a) often take an impractically long time to set, (b) release the drug content too fast, and (c) do not form pores large enough to accommodate host cells and foster osseointegration. To make up for these deficiencies, we introduced gelatin and silica to pastes composed of 5–15 nm sized hydroxyapatite …

Chitosan Nanoparticle Modifications For Improved Gene Delivery In An Oral Dna Vaccine Application, Austin Helmink

Honors Theses, University of Nebraska-Lincoln

Vaccines represent one of the most significant medical innovations of the 20^th century, resulting in the eradication or near eradication of a handful of deadly diseases. However, many infectious diseases remain resistant to effective vaccination, largely due to a lack full immune activation by traditional protein-based vaccines. A promising alternative vaccination strategy is the emerging development of DNA vaccines, which rely upon the delivery of exogenous genetic material to host cells encoding for a viral or bacterial antigen in order to induce a robust immune response by closely mimicking live infection. The delivery of genetic material requires a carrier …

Colicins - A Sound Antimicrobial Approach For The Prevention Of Catheter-Associated Urinary Tract Infections, Sandra M. Roy

Doctoral Dissertations

The emergence and spread of antibiotic resistance has created one of the greatest challenges in fighting infectious disease. We address the rise of antibiotic-resistant pathogens by examining the evolutionary history of a class of resistance determinants, the SHV b-lactamases. We isolated the genes that encode the SHV beta-lactamases (bla_SHV genes) from clinical settings and from an environment essentially devoid of antibiotic use. Our data suggests that, counter to current dogma, the use of antibiotics in the clinic is not creating these resistance genes; genes for antibiotic resistance already exist in nature and our use of antibiotics in clinical …

Succination Impairs Protein Folding And Promotes Chop Stability In The Adipocyte During Diabetes, Allison Manuel

Theses and Dissertations

Type 2 diabetes mellitus has been diagnosed in ~21 million people in the United States and is closely correlated with obesity, prompting the need for a detailed understanding of adipocyte metabolism in the development of diabetes. The intake of excess nutrients surpasses the energy requirements of the cell and leads to increased mitochondrial stress in the adipocyte. We have shown that this is associated with increased levels of the mitochondrial metabolite fumarate. Fumarate can react with cysteine thiol groups to form the chemical modification S-(2-succino)cysteine (2SC), also termed protein succination. Succination is significantly increased in the adipose tissue of type …

Functional Role Of The Homeobox Transcription Factor Six1 In Neoplastic Transformation Of Human Keratinocytes, Maria Hosseinipour

Theses and Dissertations

The homeobox transcription factor SIX1 contributes to both tumor development and progression. Numerous studies have determined that the inappropriate expression of embryonic genes, in particular transcription factors, contributes to carcinogenesis. SIX1 is essential for the development of numerous organs including the auditory and olfactory system as well as the kidney, by promoting proliferation, survival and migration of progenitor cells during embryogenesis. SIX1 has also been shown to increase cancer cell proliferation, survival and invasion. The aberrant expression of SIX1 occurs in numerous adult and pediatric cancers. We have previously determined that our in-vitro model system for HPV16-mediated tumorigenesis shares many …

Garlic Inhibits Inflammation During Dengue Infection, Alex R. Hall

Theses and Dissertations

Dengue virus (DENV) is a mosquito-borne flavivirus that causes significant human disease and mortality in the tropics and subtropics. There has been a recent global trend of increased epidemic activity, and DENV infection is considered a serious emerging health problem worldwide. A relatively unexplored approach to develop new treatments for dengue virus infection and the prevention of severe disease development is through investigation of natural medicines. Inflammation plays both beneficial and harmful roles during the host response to dengue virus infection. Several studies have proposed that it is the oxidative stress response induced by dengue virus infection that is responsible …

Muscarinic Acetylcholine Receptor M1’S Impact On Fear Extinction Learning, Joshua R. Mcelroy

Theses and Dissertations

Post-Traumatic Stress Disorder (PTSD) is a mental health disorder that can occur following a traumatic event like combat, assault, or disaster. Individuals with PTSD are unable to extinguish fear memories which can become chronic and disabling. However, it remains unclear why some individuals exposed to a traumatic event develop PTSD while others are resilient. Acetylcholine plays a critical role in fear learning, but its role in fear extinction is less well understood. In this investigation, we used a rat model of fear extinction to determine if individual differences in extinction learning are correlated with markers of cholinergic signaling. Cholinergic markers …

Synergism Of Quercetin And Sodium Butyrate For Controlling Growth Of Glioblastoma, Matthew Alan Taylor

Theses and Dissertations

Glioblastoma multiforme (GBM), or simply glioblastoma, is the most common and aggressive primary brain tumor, with a prevalence of approximately 20,000 new cases per year in the United States and a 3-year survival rate of just 2%. Quercetin (QCT) is a dietary flavonoid that can be found in common foods such as red kidney beans, cilantro, and onions. Despite little evidence showing any benefits through dietary intake of QCT, various studies show its promising anti-cancer results in vitro. In glioblastoma, QCT is able to cause significant amounts of apoptosis through a variety of mechanisms. These include activation of caspase-9 and …

Individual Differences In Markers Of Cholinergic Signaling Correlating To Fear And Extinction Learning, Grace C. Jones

Theses and Dissertations

Posttraumatic stress disorder (PTSD) results when individuals are exposed to a life threatening event, assault, serious injury, or other traumatic incident. Individuals with PTSD are impaired in their ability to extinguish fear memories, resulting in intrusive symptoms that impair their ability to live otherwise healthy lives. It remains unclear why some individuals exposed to traumatic events develop PTSD while others do not. Acetylcholine has been shown to play a critical role in fear learning, but its role in fear extinction is not well understood. This study utilized a rat model of fear learning and extinction to determine if individual differences …

The Role Of Inflammation In Atherosclerosis, Fatma Saaoud

Theses and Dissertations

Atherosclerosis is both a chronic inflammatory disease and lipid deposition disorder characterized by accumulation of lipids, fibrous tissue, and inflammatory cells in the arterial wall. Thus, investigating the role of inflammation and the immune system in the progression of atherosclerosis may help in the development of novel therapeutics for atherosclerotic disease. Current atherosclerosis therapy is aimed at lipid targets and focused primarily on reducing plasma cholesterol levels. Clinical and experimental data support the critical role of inflammation in atherosclerosis and suggest that reducing inflammation even without affecting lipid levels may reduce the event rate of cardiovascular disease. Yet, no pure …

Inhibition Of Bacterial Growth And Prevention Of Bacterial Adhesion With Localized Nitric Oxide Delivery, Julia Osborne

Dissertations, Master's Theses and Master's Reports

Bacterial infections continue to be a problem at the site of an indwelling medical device, and over the years, various bacterial strains have become more resistant to current antibiotic treatments. Bacterial infection at an indwelling medical device can be dangerous and affect the performance of the medical device which can ultimately lead to the failure of the device due to bacterial resistance to treatment.

Nitric Oxide (NO) has been shown to possess antibacterial properties to prevent and inhibit bacterial growth. NO releasing coatings on indwelling medical devices could provide a reduction in bacterial infections that occur at the device site …

The Role Of Epidermal Stem/Progenitor-Like Cells In Hpv-Mediated Pre-Neoplastic Transformation, Yvon L. Woappi

Theses and Dissertations

The role of epidermal basal stem cells in dysplasia is a matter of great interest in the human papillomavirus (HPV)-driven cancers. To assess the relationship between “stemness” and HPV-mediated transformation, we made use of 3-D suspension culture and fluorescence activated cell sorting (FACS) to purify stem/progenitor-like cells from primary normal human keratinocyte (NHKc) cultures. We found that NHKc cells derived from multicellular keratinocyte spheroids were enriched for a basal subpopulation of epidermal stem-like cells, that could be maintained for prolonged time in culture and used to conduct transfection experiments with full-length HPV16 DNA. Thus, by using these stem cell enrichment …

The Identification Of The Direct And Indirect Pathways Through Which Leptin Facilitates Synaptic Plasticity In The Hippocampus, Catherine Van Doorn

Theses and Dissertations

Leptin, a peptide synthesized by adipocytes in the periphery, has been shown to play significant roles in feeding and energy expenditure mediated by the hypothalamus. Growing evidence supports the role of leptin in influencing synaptic plasticity in the hippocampus in that leptin dose-dependently enhances LTP, alters morphology and neurogenesis, facilitates spatial learning and memory, as well as memory retention. Models of leptin deficiency and resistance have further supported the importance of leptin in synaptic plasticity by exhibiting deficits in electrophysiological, morphological and behavioral tests that are improved after leptin restoration. The effects of leptin when applied directly into the hippocampus …

Morphogenic Effects Of Dopamine In Cultured Rat Hippocampal Astrocytes, Ashley L. Galloway

Theses and Dissertations

Dopamine is critical for processing of reward and addictive behaviors brought about by drugs of abuse. Scientific investigation of drugs of abuse and their effects on CNS function has traditionally been directed at understanding the role of neurons. However, astrocytes, which constitute approximately half of all human brain cells, play a dynamic role in many essential nervous system functions, including neurotransmission, ion homeostasis, and immune defense. Dopamine effects on astrocytes have been historically understudied, yet research indicates that astrocytes express dopamine receptors and are sensitive to dopaminergic activity. Importantly, astrocytes, comprise a morphologically heterogeneous population of cells, and a distinction …

Regulation Of Chronic And Acute Inflammatory Disease By Microrna And Microbiota, Pegah Mehrpouya-Bahrami

Theses and Dissertations

Inflammation is implicated in cancer development, degenerative diseases, allergies as well as artherosecelorsis. Dysregulated immune responses lead to chronic inflammation and tissue damage. Finding the ways to terminate inflammatory responses when no longer needed, demands further investigation. Herein, we investigated the modulation of acute and chronic inflammatory disease models by inducing antiinflammatory state. Acute inflammatory model was induced with SEB, an enterotoxin produced by a ubiquitous Gram-positive coccus, Staphylococcus aureus (S. aureus), which exerts profound toxic effects on the immune system, which leads to the cytokine storm and adverse immune response. SEB is the main cause of nosocomial infections, acute …