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A Rodent Animal Model For Forelimb To Lower Jaw Reorganization In Primary Somatosensory Cortex (Si) Barrel Field, Violeta Pellicer Morata

Theses and Dissertations (ETD)

The goal of this study is to examine mechanisms underlying cortical reorganization in rat primary somatosensory (SI) cortex that follows forelimb deafferentation. The majority of human patients suffering from limb loss or brachial plexus avulsion injury, as well as patients that receive brachial plexus anesthesia, report phantom limb sensations/pain which are often associated with cortical reorganization. Patients with upper-limb deafferentation report sensations of the missing hand during tactile stimulation of the face, and this phenomenon has been termed hand-to-face remapping. We sought to develop a rodent model of deafferentation; our model system is the rat SI cortex barrel field present …

Examination Of Antiviral Resistance In Venezuelan Equine Encephalitis Virus, Jasper Lee

Theses and Dissertations (ETD)

Venezuelan equine encephalitis virus (VEEV) is a New World Alphavirus that causes Venezuelan equine encephalitis (VEE), which is characterized by a febrile illness that can progress to neurological disease and death. While no major outbreaks of VEE have occurred since 1995, VEEV is a virus of concern as, in addition to its spread through mosquitos, it can be aerosolized and used as a bioweapon. Unfortunately, there are currently no FDA-approved vaccines or antivirals against VEEV. Efforts have been made to discover small molecules with an inhibitory effect on VEEV, but the potential for emergence of antiviral resistance to these compounds …

Identification Of Effectors Of Synergistic Lethality In Candida Albicans-Staphylococcus Aureus Polymicrobial Intra-Abdominal Infection, Olivia Adele Todd

Theses and Dissertations (ETD)

Candida albicans, an opportunistic fungal pathogen, and Staphylococcus aureus, a ubiquitous pathogenic bacterium, are among the most prevalent causes of nosocomial infections and cause severe morbidity and mortality. Moreover, they are frequently coisolated from central venous catheters and deep-seated infections, including intra-abdominal sepsis. Relatively little is known about the complex interactions and signaling events that occur between microbes and even less so how microbial “cross-talk” shapes human health and disease.

Using a murine model of polymicrobial intra-abdominal infection (IAI), we have previously shown that coinfection with C. albicans and S. aureus leads to synergistic lethality whereas monomicrobial infection is nonlethal. …

Renal And Cardiovascular Outcomes Associated With Cannabis Use In Veterans With Advanced Chronic Kidney Disease Transitioning To Dialysis, Praveen Kumar Potukuchi

Theses and Dissertations (ETD)

Background: Legalization of cannabis and its constituents may lead to increased exposure of a higher number of consumers to cannabis use, including those with chronic kidney disease (CKD). We expect increase in cannabis use, especially, in patients with compromised kidney function. However, there is sparse literature on the effects of cannabis use on cardiorenal and mortality outcomes among patients with advanced CKD. Objectives: The main goal of the current study was to examine the effect of cannabis use on renal and cerebrovascular outcomes as well as mortality in patients with advanced CKD. Using a nationwide cohort of US veterans with …

Investigation Of Cell-Type-Specific Effects And Synergistic Interactions Between Genes In Duplication 15q Syndrome, Kevin A. Hope

Theses and Dissertations (ETD)

Duplication 15q syndrome (Dup15q) is a genetic disorder caused by duplications of the 15q11.2-q13.1 region and is characterized by developmental delay, autism spectrum disorder, and treatment resistant epilepsy. Extra copies of the E3 ubiquitin ligase UBE3A and elevated levels of UBE3A expression in neurons are thought to be the primary cause of Dup15q phenotypes. However, animal models overexpressing UBE3A in neurons have not successfully recapitulated all aspects of Dup15q syndrome, especially epilepsy. Here, we used Drosophila melanogaster (fruit flies) to investigate Dup15q syndrome. In Chapter 2 we explored whether Dube3a, the Drosophila homolog of UBE3A, is imprinted in the fly …

Rheological Studies Of Injectable Thermoresponsive Biodegradable Hydrogels And Porcine Ocular Tissues, Chandana Reddy Damera

Theses and Dissertations (ETD)

This research has evaluated the rheological properties of two types of materials which include (i) semi-synthetic polymer-based injectable hydrogels [P(NIPAAm-co-DEX-Lactate HEMA) and P(NIPAAm-co-HA-AEMA)], and (ii) biological tissues (porcine ocular tissues).

A series of thermoresponsive and biodegradable in situ hydrogel based on N-isopropyacrylamide (NIPAAm) monomer and hydrolytically degradable oligolactate Dextran-lactate-HEMA or Hyaluronic acid (HA)-AEMA macromer were investigated as encapsulation matrices (scaffolds) for DPSCs/ADSCs and assess their applicability in dental/retinal tissue engineering. The rheological properties of the hydrogels were strongly dependent on the reaction conditions and composition of the hydrogels. Both the hydrogels exhibited linear viscoelasticity, and the values of storage moludus …

Habituation And Dishabituation In The Olfactory Bulb: From Neural Responses To Behavior, Mary Cameron Ogg

Theses and Dissertations (ETD)

Habituation and dishabituation modulate the neural resources and behavioral significance allocated to incoming stimuli across the sensory systems. The purpose of the research presented in this dissertation was to characterize these processes in the mouse olfactory bulb (OB) and to determine if OB acetylcholine (ACh) has a role in physiological and behavioral olfactory dishabituation. Calcium imaging was used to determine the timecourse and magnitude of habituation in different parts of the OB during and after a prolonged odor presentation. Widefield imaging of the dendritic, or glomerular, response of OB output cells demonstrated that prolonged odor input habituates glomerular responses during …

Pitx3null Mutant (Striatal Dopamine-Deficient) Mice Have Exaggerated Spiny Projection Neuron Responses To L-Dopa And D1 Agonism And Lack Baseline Striatonigral Spiking, Ben Sagot

Theses and Dissertations (ETD)

L-3,4 dihidroxyphenylalanine (l-DOPA) strongly stimulates motor activity in parkinsonian patients and animal models of Parkinson's disease. Severe striatal dopamine (DA) loss characterizes Parkinson's disease and its animal models. Given the canonical rate model of Parkinson's Disease pathophysiology based on differences in DA pharmacology manifesting as electrophysiological differences in striatal projection neuron (SPN) spike rates, SPNs should increase spiking during the motor response to l-DOPA. In fact, stimulating specific subsets of these neurons to spike in freely-moving wild type and parkinsonian animals causes or inhibits motor activity as predicted. However, pharmacological effects of DA deficiency, let alone those of DA replacement, …

Cannabinoid Receptor 2 (Cb2) Ligands Downregulate Pro-Inflammatory Markers In Stimulated Primary Human Periodontal Ligament Fibroblasts (Hpdlfs), Ammaar Hasan Abidi

Theses and Dissertations (ETD)

There are approximately 743 million individuals suffering from chronic periodontitis (PD) making it the sixth most prevalent condition worldwide. The affected adult population in the U.S. are nearly 64.7 million and the healthcare costs exceeds $14 billion. Recently, host response to pathogenic infection has been seen critical to the progression of PD and exhibit increase in various inflammatory markers. Marijuana is well known for its recreational usage and is a risk factor for periodontal disease, which is seen as a concern in society for its negative health consequences. However, many medical conditions can benefit from the pharmacological effects of cannabinoids. …

Automatic Activation Of Phonological Templates For Native But Not Nonnative Phonemes: An Investigation Of The Temporal Dynamics Of Mu Activation, Daniela Cristina Santos-Oliveira

Theses and Dissertations (ETD)

Models of speech perception suggest a dorsal stream connecting the temporal and inferior parietal lobe with the inferior frontal gyrus. This stream is thought to involve an auditory-motor loop that translates acoustic information into motor/articulatory commands and is further influenced by decision making processes that involve maintenance of working memory or attention. Parsing out dorsal stream’s speech specific mechanisms from memory related ones in speech perception poses a complex problem. Here I argue that these processes may be disentangled from the viewpoint of the temporal dynamics of sensorimotor neural activation around a speech perception related event.

Methods: Alpha (~10Hz) and …

Neuroanatomical Maps And Taste Reactivity To Sweet, Umami, And Bitter Taste In The Pbn Of C57bl/6j Mice, Jennifer Marie Saputra

Theses and Dissertations (ETD)

Humans can distinguish at least five different taste qualities, sour, salty, bitter, sweet, and umami (the savory taste of certain amino acids). In neuroscience research, behavioral testing is used to measure the ability of rodents (including inbred mice) to discriminate between the different taste qualities. Taste reactivity and two-bottle preference are behavioral tests that are utilized to investigate different aspects of taste. These tests involve either voluntary or forced consumption of taste stimuli, respectively. Either test can be used to infer the preference and palatability of the stimulus consumed by an animal.

In order to understand the basis of taste …

Synthesis And Characterization Of Methacrylated Hyaluronan-Based Hydrogels For Tissue Engineering, Keegan Bradley Compton

Theses and Dissertations (ETD)

Polymers have revolutionized the field of tissue engineering due to the countless possibilities of scaffolds that can be constructed from such a material. Through conjugation of other functional groups onto a polymer backbone, the mechanical properties of polymers can be controlled and has the ability to span a wide range of strengths, allowing for application in multiple tissue environments. One such polymer, hyaluronic acid (HA), is a natural polysaccharide found most abundantly in the extracellular matrix (ECM) of connective tissues with structural, lubricating, and wound healing functions in the human body; for this reason, HA has great potential for utilization …

The Health-Related Quality Of Life Of Adults With Down Syndrome, Rebecca Jermyn Graves

Theses and Dissertations (ETD)

Purpose. The purpose of this study was to examine the health-related quality of life (HRQOL) and factors associated with the HRQOL of adults with Down syndrome (DS) as reported by adults with DS and their caregivers. The study was designed to compare measures of HRQOL, health problems, health risks, and health-care utilization of adults with DS based on self-report with those from caregiver-report and to explore associations between HRQOL and health problems, health risks, health-care utilization, adaptive behavior, and demographic characteristics. Background. The life expectancy of individuals with DS has lengthened from approximately 30 years around 1960 to over 50 …

Signal Transduction And Transcriptional Regulation Pathways Essential For Azole Resistance In Candida Albicans, Erin M. Vasicek

Theses and Dissertations (ETD)

Candida albicans is the most prevalent human fungal pathogen, found as a commensal organism in the mucosa, gastrointestinal, and urogenital tracts of humans. This pathogenic fungus causes a wide spectrum of diseases, including the mucosal infection oropharyngeal candidiasis (OPC) which frequently effects patients with human immunodeficiency virus (HIV). The azole antifungals (such as fluconazole) are the most widely used and important ergosterol biosynthesis inhibitors (EBIs) for the treatment of Candida infections, including OPC. However, the azoles are fungistatic against C. albicans and therefore have limited efficacy against this organism, especially for immunocompromised patients. In C. albicans, the transcription factor Upc2 …

Changes In Pharyngeal Airway Dimensions Due To Mara Treatment In Class Ii Malocclusions, James K. Dillehay

Theses and Dissertations (ETD)

Orthodontic treatment effects on the pharyngeal airway have recently become a hot topic in the field of orthodontics. Current literature has shown facial skeletal morphology to be correlated with pharyngeal airway shape and volume. This study used CBCT imaging to identify what, if any, effects two different treatment modalities for correcting Class II malocclusions have on the pharyngeal airway volume. This retrospective study consisted of two groups of Class II patients: 38 patients (15 females, 23 males) treated with the MARA and an Edgewise appliance and 32 patients treated with an Edgewise appliance and Class II elastics. Both pre and …

Treatment Effects Of The Mandibular Anterior Repositioning Appliance (Mara) And Conventional Orthodontic Mechanics On Temporomandibular Joint Morphology: A Comparison Using Cone Beam Computed Tomography, Brenton E. Glassell

Theses and Dissertations (ETD)

Introduction: An ongoing debate exists in orthodontics about the amount of condylefossa remodeling and growth seen in Class II patients using functional appliance therapy. Some clinicians and researchers have found that that the use of functional appliances increases the amount of condylar growth and subsequent Class II skeletal correction; others believe that the mandible has a preset amount of growth and that conventional orthodontics will result in a similar amount of condylar growth to functional appliance therapy. Purpose: The aim of this study was to compare condylar remodeling in functional appliance treatment using the mandibular anterior repositioning appliance (MARA) to …

Verification Of The Accuracy Of Electronic Mandibular Movement Recording Devices: : An In Vitro Investigation, Joshua Heath Balch

Theses and Dissertations (ETD)

One goal of restorative dentistry is to truly capture maxillomandibular relationships that accurately reproduce mandibular border movements and that would prescribe the best occlusal interface. Registration of horizontal and sagittal movements of the patient allows maximum cusp height and fossae depth with proper placement of occlusal ridges and grooves. The goal is to develop an occlusion that is interference free and entails the concepts of organic occlusion. Methods to transfer patient information to a highly adjustable articulator include mechanical recorders, mechano-electronic recorders and optoelectronic recorders. The purpose of this study is to verify the accuracy of electronic mandibular movement recording …

In Vitro Staining Of Denture Liners And Potential For Color Correction Using Commonly Available Denture Cleansers, Russell D. Morrell

Theses and Dissertations (ETD)

Background: Denture liners are routinely used as part of immediate denture therapy, following surgery involving edentulous tissues, and to improve the function and stability of existing removable prostheses. Appropriate application of denture liners can facilitate patient comfort during prolonged therapy and prior to placement of definitive restorations. However, concern has been raised regarding the susceptibility of common denture liners to agent-induced color change which, in turn, adversely impacts the esthetic appeal of the associated removable prosthesis.

Objective: The purpose of the study was to evaluate the color stability of denture liners exposed to commonly encountered food stains and commonly used …

Metabotropic Glutamate Receptor 5 In The Medial Prefrontal Cortex: Role In Cocaine Sensitization And Addiction, Kristin Marie Timmer

Theses and Dissertations (ETD)

Cocaine sensitization is associated with cocaine-induced hyperexcitability of pyramidal projection neurons within the medial prefrontal cortex (mPFC). Such hyperexcitability presumably results in increased glutamatergic input to reward-affiliated brain regions such as the ventral tegemental area (VTA) and nucleus accumbens (NAc), consequently facilitating drugseeking behavior. Metabotropic glutamate receptor 5 (mGluR5) has been implicated in cocaine addiction and demonstrated to increase neuronal excitability, therefore, the aim of the present study was to investigate the effect of intra-mPFC mGluR5 manipulation on behavioral and neurochemical sensitization and drug-seeking. Bilateral cannulae were implanted into the mPFC of male Sprague-Dawley rats and mGluR5 antagonist MTEP (15 …

Rankl And Osteoprotegerin Levels In Response To Orthodontic Forces, Katherine Ann Hart D.D.S.

Theses and Dissertations (ETD)

Orthodontic tooth movement is mediated by interactions between PDL cells and those of the alveolus. One protein—the receptor activator nuclear factor kappa B ligand (RANKL)—is critical for osteoclastogenesis, and osteoprotegerin (OPG) is a decoy ligand that competitively inhibits RANKL. A higher RANKL/OPG ratio is associated with areas of bone resorption, while a lower ratio occurs in areas of bone deposition and homeostasis. There have been almost no clinical studies of RANKL and OPG expression in human subjects undergoing orthodontic tooth movement. The purpose of this study was to quantify changes in the levels of RANKL and of OPG expression in …

A Secular Increase In The Tempos Of Tooth Formation: 1980-2010, Kevan Michael O'Neill

Theses and Dissertations (ETD)

Introduction: Improved environments in the U.S. have resulted in taller, larger, and heavier children and adults compared to past generations. Studies of other skeletal-dental dimensions have shown increases across generations, and our perception is that teeth now are forming faster. The purpose of this study is to test for a secular trend towards faster tempos of tooth mineralization in a sample of U.S. white adolescents over the past quarter century (1980-85 to 2005-10).

Materials: Two cohorts of 200 children each were identified, each with an age range of 10-to- 15 years, one group from 1980-85 and the more recent group …

Skeletal And Dental Components Of Class Ii Division 1 Correction With The Mara Compared To The Standard Edgewise Appliance, Zachary Paul Pitcher

Theses and Dissertations (ETD)

Many tools are available to correct Class II dental relationships. A functional orthopedic appliance is a popular type of Class II corrector that is thought to correct Class II dental relationships both dentally and skeletally by enhancing mandibular growth. The purpose of the study was to quantify differences in the amounts of skeletodental change based on treatment (MARA and Standard Edgewise) in Class II Division 1 patients. The sample consisted of 2 groups of Class II Division 1 patients: 51 patients treated with the MARA followed by an Edgewise appliance and another group of 51 patients treated with the Standard …

Pronthocyanidin-Rich Cranberry-Fractioninduced Alteration Of Periodontal Pathogen Lipopolysaccharide Functions, Vreiti Sangha

Theses and Dissertations (ETD)

The cranberry (species: Vaccinium macrocarpon, family: Ericaceae) is a polyphenolicrich berry fruit native to North America and exhibits numerous beneficial properties for human health, such as inhibition of human cancer cell line proliferation and prevention of urinary tract colonization by bacterial pathogens. The proanthocyanidin rich cranberry fraction has long been speculated to possess the capacity to reduce the production of inflammatory mediators by LPSstimulated macrophages and gingival fibroblasts and to inhibit host extracellular matrix destructive enzyme production and activity.

The purpose of this investigation was to examine the effect of cranberry non dialyzable material (NDM), which was shown to be …

Oropharyngeal Airway Volume Following Orthodontic Treatment: Premolar Extraction Versus Non-Extraction, Thomas Patrick Shannon

Theses and Dissertations (ETD)

Orthodontic correction of tooth size versus arch size discrepancy (TSASD) can be achieved with two distinct methods of treatment. The first involves the extraction of teeth to gain the space needed for tooth alignment. The second relies on arch expansion to gain the space needed for correction. In recent decades, arguments for and against the extraction of teeth for orthodontic purposes have become increasingly important, particularly in regards to oropharyngeal airway size. Purpose: The purpose of this study is to determine whether there is a decrease in oropharyngeal dimensions following the extraction of four premolars and subsequent orthodontic therapy. Methods: …

Oropharyngeal Airway Volume Following Orthodontic Treatment: Premolar Extraction Versus Non-Extraction, Thomas Patrick Shannon

Theses and Dissertations (ETD)

Orthodontic correction of tooth size versus arch size discrepancy (TSASD) can be achieved with two distinct methods of treatment. The first involves the extraction of teeth to gain the space needed for tooth alignment. The second relies on arch expansion to gain the space needed for correction. In recent decades, arguments for and against the extraction of teeth for orthodontic purposes have become increasingly important, particularly in regards to oropharyngeal airway size. Purpose: The purpose of this study is to determine whether there is a decrease in oropharyngeal dimensions following the extraction of four premolars and subsequent orthodontic therapy. Methods: …

Evaluating Dimensional Accuracy And Reliability Of "Stitched" Small Field Of View (Ssfov) Cone Beam Computed Tomography (Cbct) Datasets For Use In Proprietary Dental Implant Guided Surgery Software, Nicholas Luke Egbert

Theses and Dissertations (ETD)

Background: Recently a "stitched" small field of view (SSFOV) cone beam computed tomography (CBCT) extraoral imaging system (Kodak 9000D, Carestream Health Inc, Kodak Dental Systems, Marne‑la‑Vallee, France) has been released. The benefits of the 3D stitching module of stitched SFOV CBCT may include: broader range of applications, affordability, flexibility, safety optimizing radiation dose and improved workflow. With the reduced effective dose of radiation and cost to both the patient and clinician, this superior imaging modality becomes more accessible to the community, potentially elevating the standard of care. Currently, stitched data sets are restricted to diagnostic data gathering only. To date, …

Eccentric Interchangeability Of The Semi‑Adjustable Articulator: A Pilot Study, Mark James Hopkins

Theses and Dissertations (ETD)

Background: Dental articulation is a method of approximating the patient's mandibular motion in order to allow for analysis of dental relations and fabrication of appliances. The most prevalent method used in teaching institutions is the semi-adjustable articulator. Several of these instruments claim interchangeability without loss of clinical accuracy and studies have supported this claim. No studies to date have assessed the interchangeability of the articulators in any relation other than hinge axis closure. Assessment of the accuracy of interchangeability of calibrated articulators will inform the profession of this parameter of articulation and allow for informed decisions on whether or not …

Efficacy Of Temporary Fixed Retention Following Comprehensive Orthodontic Treatment, Mark J. Owens

Theses and Dissertations (ETD)

Instability of the occlusion is a common problem following orthodontic treatment. The purpose of the present research was to evaluate posttreatment relapse at long-term recall (> 10 years) in cases (A) treated with temporary fixed mandibular retention plus Hawley retainers compared to (B) a similar group retained with just removable retention (standard Hawley type retainers alone). Fixed retainers were removed after having been in place for about 2.5 years. Following this period, use of removable retention was left up to the discretion of the patient in both groups. Data consisted of orthodontic records of 166 American whites, all of whom …

Activity Of Epithelial Defensin Hbd-3 Against A Periodontal Pathogen, Norman B. Fine

Theses and Dissertations (ETD)

Defensins are cationic (positive-charged) peptides with broad-spectrum antibiotic activity. In humans, there are two types of defensins, alpha (α) and beta (β). Human neutrophils contain four α-defensins known as Human Neutrophil Peptide (HNP) 1-4. Epithelial cells produce four β-defensins known as Human Beta Defensin (HBD) 1-4. Gram-negative anaerobic bacteria that are associated with periodontal disease are resistant to human α-defensins, but are killed by β-defensins.

HBD-3 is the most active β-defensin. HBD-3 is a longer peptide than HNP 1-4. HBD-3 has additional amino acid residues with hydrophobic side chains near the N-terminus and residues with cationic side chains at the …

The Long-Term Stability Of Class Ii Cases Treated In A Private Practice Using A Straightwire Appliance: A Dental Cast Analysis, Lina K. Kulkarni

Theses and Dissertations (ETD)

Achieving long-term stability after orthodontic treatment is a major challenge for orthodontists. The previous literature shows that relapse occurs at a considerable magnitude. The purpose of the present study was to determine the amount and type of long-term, posttreatment relapse that occurs in a homogeneous group of patients treated by a single experienced orthodontist in a private practice setting. Dental casts from a sample of 30 Class II division 1 Caucasian females treated without extractions were evaluated at pretreatment (mean age = 13.1 years), posttreatment (mean age = 15.9 years) and recall (mean age = 28.3 years) to determine the …