Biomedical and Dental Materials Commons^™

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 Program: Senior Projects (Public)

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

Differences In Resting-State Functional Connectivity Of Chronic Migraine, With And Without Medication Overuse Headache, And The Effectiveness Of Sphenopalatine Ganglion Block As A Treatment For Repairing Dysfunctional Connectivity., Kaitlin Krebs

Theses and Dissertations

Chronic Migraine (CM) is a debilitating neurological condition that occurs when the migraine frequency progresses to a chronic state of more than 15 headache days per month. The overuse of analgesic medication (MOH) is one of the most prominent risk factor of this chronification and little is known about why it is a cause. The repetitive inhibition of the Sphenopalatine Ganglion is one promising treatment that is used to treat chronic migraine. The purpose of this study is to determine if a specific pattern of disruption is present for chronic migraine, both with and without medication overuse headache, and if …

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 …

Bio-Inspired Composite Hydrogels For Osteochondral Regenerative Engineering, Grant N. Gellert, Liangju Kuang, Chunhui Jiang, Nur P. Damayanti, Joseph Irudayaraj, Meng Deng

The Summer Undergraduate Research Fellowship (SURF) Symposium

Treatment of osteochondral defects encompassing injury or degeneration to both the articular cartilage as well as the underlying subchondral bone presents a significant medical challenge. Current treatment options including autografts and allografts suffer from limited availability and risk of immunogenicity, respectively. The long term goal of this work is to develop an integrated scaffold system for treatment of osteochondral defects via in situ regeneration of bone, cartilage and the bone-cartilage interface. Hydrogels composed of polymer networks swollen in water provide an attractive biomaterial platform for regeneration of cartilage. In the present study, we have developed a novel composite hydrogel consisting …

Effects Of Pringle Maneuver And Partial Hepatectomy On The Pharmacokinetics And Blood–Brain Barrier Permeability Of Sodium Fluorescein In Rats, Mohammad K. Miah, Imam H. Shaik, Ulrich Bickel, Reza Mehvar

Pharmacy Faculty Articles and Research

Liver diseases are known to affect the function of remote organs. The aim of the present study was to investigate the effects of Pringle maneuver, which results in hepatic ischemia–reperfusion (IR) injury, and partial hepatectomy (Hx) on the pharmacokinetics and brain distribution of sodium fluorescein (FL), which is a widely used marker of blood–brain barrier (BBB) permeability. Rats were subjected to Pringle maneuver (total hepatic ischemia) for 20 min with (HxIR) or without (IR) 70% hepatectomy. Sham-operated animals underwent laparotomy only. After 15 min or 8 h of reperfusion, a single 25-mg/kg dose of FL was injected intravenously and serial …

Stability Of Lidocaine Tested By Forced Degradation And Its Interactions With Serum Albumin, Lindsay Nichols

STAR Program Research Presentations

A concern for future long-term manned space expeditions is the ability to treat illnesses with appropriate pharmaceuticals. However, pharmaceuticals degrade faster in space than on Earth presumably due to an abundance of space radiation. The stability of Lidocaine was investigated because it is a common pain reliever currently used on the International Space Station. One of the most common proteins in blood is serum albumin, which acts as a carrier to distribute drugs throughout the body. It is important to know how well the drug binds to serum albumin so that the rate of distribution of Lidocaine-bound protein in blood …

Engineering Approaches For Suppressing Deleterious Host Responses To Medical Implants, Connor Mccarthy

Dissertations, Master's Theses and Master's Reports

Small diameter (< 6 mm) vascular grafts suffer from serious deleterious effects not encountered with their larger diameter relatives, leading to premature graft failure through restenosis. Platelet activation, inflammation, and smooth muscle cell proliferation are leading contributors to thrombosis and neointimal hyperplasia, both contributors to the progression of restenosis. It may be possible to suppress negative biological responses to vascular implants through the modification of surface properties and incorporation of drug release into blood contacting materials. In this work, bioengineering approaches are presented to improve the biocompatibility of small diameter vascular grafts.

We demonstrate a novel engineering approach for incorporating natural, decollagenized elastin matrices into PEU 1074A reinforced vascular grafts through spray-coating and electrospinning processes in a manner that retains elastin’s excellent blood contacting properties. A vascular construct with excellent mechanical and surgical handling properties demonstrating the suppression of neointimal hyperplasia is presented after 21 days in vivo.

Nitric oxide (NO) has been investigated over the past several decades due to its platelet, inflammation, and smooth muscle cell suppressing effects; and if appropriately delivered, could positively mediate the contributors to restenosis. Here, we characterize a novel macrocyclic NO …

Use Of Swine Small Intestine Submucosa As A Dermal Suture, Paige E. Black

PCOM Biomedical Studies Student Scholarship

The purpose of this preliminary study is to determine if swine small intestine submucosa (SIS) can be used to create a suture that will perform comparably to commercially available chromic gut sutures when placed into a wound in rat dermis. This study is part of an ongoing collaboration that has explored SIS as a biologic scaffold in various tissues and surgical procedures. In this study, eight Sprague-dawley rats were divided into two groups, each receiving a full thickness skin wound between the scapula, made by a 5mm biopsy punch. The wound was then closed with commercially available chromic gut suture, …

Characterization Of Stard4 And Stard6 Proteins In Human Ovarian Tissue And Human Granulosa Cells And Cloning Of Human Stard4 Transcripts, Aisha Shaaban

Theses and Dissertations

Progesterone is essential hormone for pregnancy, which is produced by the human corpus luteum in early pregnancy until the placenta assumes this function. Transport of the cholesterol from the outer to the inner mitochondrial membrane is the rate limiting step for the de novo synthesis of pregnenolone (the precursor to progesterone), a process mediated by STARD1. STARD1 contains a C-terminal lipid binding domain which binds cholesterol and an N-terminal domain targeting STARD1 to the mitochondrial membrane. Unlike STARD1, STARD4 and STARD6 proteins lack a mitochondrial targeting sequence; however, they can bind cholesterol and increase steroidogenesis in model systems. In this …

Bioerodible Calcium Sulfate Bone Grafting Substitutes With Tailored Drug Delivery Capabilities, Bryan R. Orellana

Theses and Dissertations--Biomedical Engineering

Bone regeneration or augmentation is often required prior to or concomitant with implant placement. With the limitations of many existing technologies, a biologically compatible synthetic bone grafting substitute that is osteogenic, bioerodible, and provides spacing-making functionality while acting as a drug delivery vehicle for bioactive molecules could provide an alternative to ‘gold standard’ techniques.

In the first part of this work, calcium sulfate (CS) space-making synthetic bone grafts with uniformly embedded poly(β-amino ester) (PBAE) biodegradable hydrogel particles was developed to allow controlled release of bioactive agents. The embedded gel particles’ influence on the physical and chemical characteristics of CS was …

Modified Seed Growth Of Iron Oxide Nanoparticles In Benzyl Alcohol: Magnetic Nanoparticles For Radio Frequency Hyperthermia Treatment Of Cancer, Stanley E. Gilliland Iii

Theses and Dissertations

Iron oxide nanoparticles have received sustained interest for biomedical applications as synthetic approaches are continually developed for precise control of nanoparticle properties. This thesis presents an investigation of parameters in the benzyl alcohol synthesis of iron oxide nanoparticles. A modified seed growth method was designed for obtaining optimal nanoparticle properties for magnetic fluid hyperthermia. With a one or two addition process, iron oxide nanoparticles were produced with crystallite sizes ranging from 5-20 nm using only benzyl alcohol and iron precursor. The effects of reaction environment, temperature, concentration, and modified seed growth parameters were investigated to obtain precise control over properties …

Comparison Of Corded And Cordless Handpieces On Forearm Muscle Activity, Procedure Time And Ease Of Use During Simulated Tooth Polishing, Gayle Mccombs, Daniel M. Russell

Dental Hygiene Faculty Publications

Purpose: Dental professionals suffer from a high prevalence of work-related musculoskeletal disorders (MSD). Dental hygienists in particular have a high prevalence of pain in the forearms and hands. The objective of this study was to compare 1 cordless handpiece to 2 corded handpieces during simulated tooth polishing in terms of the muscle loads (recorded as electromyography (EMG) activity), duration of polishing procedure, and dental hygienist opinion about ease of use. Methods: EMG was used to quantify muscle electrical activity of 4 forearm muscles during simulated dental polishing with 2 corded handpieces (HP-A and HP-B) and 1 cordless handpiece (HP-C). A …

Combatting Dental Anxiety In Patients, Gretchen Osdoba

Natural Science Student Work

Dental Anxiety is a highly debilitating condition that can keep people away from the dentist and from receiving critical care. This can lead to serious medical conditions that could have easily been prevented through proper dental care. The purpose of this paper is to describe the nature of dental fear and the different treatment options available. I will focus on helpful traits of dentists and the use of psychological treatments, nitrous oxide, anti-anxiety medications, and general anesthesia to reduce this fear. I will also discuss a comparison of a psychological treatment and an anti-anxiety medication as short-term and long-term treatment …

Frictional Forces Of A Fixed, Esthetic Orthodontic Appliance System, Brady Michael Nance

UNLV Theses, Dissertations, Professional Papers, and Capstones

Purpose: The demands of an all esthetic fixed orthodontic appliance system are ever increasing in today's world. Frictional values of an esthetic, fixed orthodontic appliance system are needed to evaluate their clinical effectiveness for orthodontic treatment. The aim of this study is to evaluate the frictional values of various esthetic orthodontic archwires ligated to an esthetic orthodontic bracket.

Methods: Three types of stainless steel and nickel titanium alloy (niti) esthetic orthodontic archwires (epoxy, poly, plastic) in four sizes (.016, .018, .017 x .025, .019 x .025 inches) were ligated to both a stainless steel bracket system and a ceramic (esthetic) …

Finite Element Analysis Of Stress Distribution Within Metal-On-Metal Joint Replacements, Yujing Liu

Theses: Doctorates and Masters

Demand for joint replacements is rising in Australia, driven by a sharp increase in the number of joint problems associated with population aging and obesity. In artificial joints, delamination or failure within the coatings occurs when the stress reaches a critical level, resulting in large wear debris particles appearing on the contact surface between the head and the cup. The process has been described as due to a stress-corrosion-cracking mechanism. Under the same loading, stress increases when the contact area decreases, which happens in the vicinity of wear debris. As such, once wear debris is generated, a catastrophic process could …

The Effect Of Mtad On Eight Strains Of E. Faecalis In Contaminated Root Canals, Bradley M. Newberry

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this investigation was to determine the antimicrobial effect of Biopure MTAD (a mixture of a tetracycline isomer, an acid, and a detergent) as a final irrigant on eight strains of Enterococcus faecalis (E. faecalis) in contaminated root canals of extracted human teeth. In addition, the Minimum Inhibitory Concentration (MIC) and Minimum Lethal Concentration (MLC) of MTAD were also measured on the same strains of bacteria. Two-hundred and forty extracted human teeth were instrumented using 1.3% NaOCl followed by 17% EDTA to remove the smear layer. The teeth were randomly contaminated with one of eight strains of E. …