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The Mi-2 Homolog Mit1 Actively Positions Nucleosomes Within Heterochromatin To Suppress Transcription, Kevin M. Creamer

Theses and Dissertations (ETD)

Eukaryotic DNA is packaged into the nucleus in complex with proteins that regulate access and utilization of the genetic material. These DNA and protein complexes form a dynamic structure known as chromatin. Nucleosomes are the repeating unit of chromatin, and consist of DNA wrapped around an octamer of histone proteins. Nucleosomes can then be modified and spatially arranged to facilitate processes such as transcription, DNA replication, and repair. A special transcriptionally repressive chromatin structure assembles onto gene-poor, repetitive regions of the genome known as constitutive heterochromatin. Mit1 is the putative chromatin remodeling subunit of the fission yeast Snf2/HDAC repressor complex …

Antioxidant Gene Therapy Against Neuronal Cell Death, Juliana Navarro-Yepes, Laura Zavala-Flores, Anandhan Annadurai, Fang Wang, Maciej Skotak, Namas Chandra, Ming Li, Aglaia Pappa, Daniel Martinez-Fong, Luz Maria Del Razo, Betzabet Quintanilla-Vega, Rodrigo Franco

Department of Psychology: Faculty Publications

Oxidative stress is a common hallmark of neuronal cell death associated with neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, as well as brain stroke/ischemia and traumatic brain injury. Increased accumulation of reactive species of both oxygen (ROS) and nitrogen (RNS) has been implicated inmitochondrial dysfunction, energy impairment, alterations in metal homeostasis and accumulation of aggregated proteins observed in neurodegenerative disorders, which lead to the activation/modulation of cell death mechanisms that include apoptotic, necrotic and autophagic pathways. Thus, the design of novel antioxidant strategies to selectively target oxidative stress and redox imbalance might represent important therapeutic approaches against neurological disorders. …

Propagation Of Oligomeric Α-Synuclein And Amyloid-Β: Implications For Parkinson's And Alzheimer's Diseases, Matthew Stephen Planchard

Master's Theses

The aggregation of amyloidogenic proteins is a critical event in the pathology of a variety of neurodegenerative diseases, including Alzheimer’s disease (AD) and Parkinson’s disease (PD). The proteins α-synuclein (αS) and amyloid-β (Aβ) are involved in the formation of amyloid lesions observed in PD and AD, respectively. Both PD and AD exhibit a significant amount of co-pathology in clinical settings, and the αS and Aβ proteins have been shown to interact in vitro. Recent experimental consensus has shown oligomeric species to be significant, if not primary, sources of toxicity in these diseases. …

The Role Of Glutamate Signalling In Diabetic Neuropathy, Nadia Hussain

Dissertations

The majority of diabetics develop neuropathy, which can be debilitating, but the underlying pathophysiological mechanisms are poorly understood. Diabetic neuropathy progresses in a distal to proximal manner. Previous studies have shown that glutamate, the most common excitatory neurotransmitter, plays a role in the pathogenesis of neuropathy. The reason why the role of glutamate in nociception becomes a problem in diabetes and the mechanisms that are involved are unknown. Based on the preliminary data, the hypothesis was that glutamate pathways are likely to be involved in diabetic neuropathy particularly neuropathic pain. Pathways were investigated to look for changes that might reflect …

Hypoxic Signals In The Ischemic Myocardium: Role Of Galectin-1 And Galectin-3, Satwat Hashmi

Dissertations

Myocardial infarction is the most serious manifestation of coronary artery disease and the cause of significant levels of mortality and morbidity worldwide. Galectin-1 (GAL-1) and Galectin-3 (GAL-3) are beta galactoside binding lectins with diverse functions. Hypoxia inducible factor-1 alpha (HIF-1α) is a transcription factor mediating early and late responses to myocardial ischemia. We aim to study the direct effects of ischemia on GAL-1, GAL-3 and HIF-1α in the heart. Male C57B6/J and GAL-3 knockout mice were used for our two disease models. In the Myocardial infarction (MI) model, the left anterior descending artery of the heart is permanently ligated to …

Epigenetic Remodeling In An Imr-32 Cell Line And Transgenic Mouse Model Of Alzheimer's Disease, Matthew S. Baker

Senior Honors Theses

The pathological features of Alzheimer’s disease (AD) have been researched and documented extensively, however the causes of these features are still unknown. The following studies sought to determine if epigenetic methylation alterations contribute to AD. Two studies were sequentially carried out, first using an IMR-32 model and then using a transgenic mouse model overexpressing beta-amyloid. A few assay and confirmation methods were carried out to determine the promoter regions in disease state models undergoing drastic change, and the genes linked to these promoter regions were analyzed to determine significant gene ontology being altered by this epigenetic modification. This data was …

Tethered Il-15 To Augment The Therapeutic Potential Of T Cells Expressing Chimeric Antigen Receptor: Maintaining Memory Potential, Persistence, And Antitumor Activity, Lenka Hurton

Dissertations and Theses (Open Access)

Tethered IL-15 to augment the therapeutic potential of T cells expressing chimeric antigen receptor: Maintaining memory potential, persistence, and antitumor activity

Adoptive immunotherapy can retarget T cells to CD19, a tumor-associated antigen (TAA) expressed on B-cell malignancies, by the expression of a chimeric antigen receptor (CAR). Infusion of CAR-modified T cells for the treatment B-cell malignancies has demonstrated promise in preclinical and clinical trials. These data highlight the ability of infused CD19-specific T cells to be synchronously activated by large burdens of CD19⁺ leukemia and lymphoma. This can lead to dramatic antitumor effects, but also exposes the recipient to …

Differential Regulation Of Iress In The Aurora A Mrna By Bfgf Through The Mtor Complex To Rc2 Modulates Aurora A Kinase Expression, Roy L. Voice Iii

Dissertations and Theses (Open Access)

Identifying the mechanisms that contribute to tumorigenesis is a major area of focus in our fight against cancer. Epithelial malignant tumors, such as breast, colon, ovarian and pancreatic cancers have been shown to overexpress proteins that control cell mitosis, growth, and proliferation. One of those proteins is the Aurora A kinase. Aurora A kinase is a member of a small family of kinases that contribute to mitotic events such as centrosome duplication, separation, and maturation. Aurora A overexpression leads to genomic instability, which can contribute to tumorigenesis, on the other hand, inhibiting Aurora A expression leads to apoptosis, making it …

Development Of A Multi-Purpose Automated Synthesis Module For Production Of Novel Pet Radiopharmaceuticals, I Hong Shih

Dissertations and Theses (Open Access)

Among radiopharmaceuticals of positron emission tomography (PET), ¹⁸F-Fluorodeoxyglucose (¹⁸F-FDG) made from commercialized automated synthesis module is the most frequently used in tumor diagnoses. But the false positive findings, such as infectious tissues and post-operative surgical conditions, show strong uptake of ¹⁸F-FDG in PET scans which requires extra clinical procedures to confirm the results. Moreover, the false negative findings, such as low glycolytic activity tumors, reduce the accuracy of PET scans. Therefore, there will be new PET radiopharmaceuticals to redeem the defects of ¹⁸FDG-PET applications.

Current commercialized automated synthesis modules are suitable for clinical use, but …

Eye-Tracking Measures Of Attentional Bias In Cocaine Dependent Subjects, Nadeeka Dias

Dissertations and Theses (Open Access)

Cocaine-dependent (CD) subjects show evidence of attentional bias toward cocaine-related cues, and this measure of cue-reactivity is predictive of craving and relapse. In previous work, cue-reactivity and attentional bias have been assessed by models that present drug-relevant stimuli (e.g., cocaine-specific Stroop task) and measure physiological and behavioral reactivity (e.g., heart rate, reaction times). Studies have indicated competition between the higher-order cortical processes (frontal eye-fields, DLPFC) in voluntary eye control (i.e., anti-saccades) and more reflexive saccades driven by involuntary midbrain (superior colliculus) perceptual input (i.e., pro-saccades). In addition, neuroimaging studies in patients with cocaine dependence have shown activation in frontal regions …

Evaluation Of Current Clinical Criteria For Li-Fraumeni Syndrome In A Diverse Sample Of Tp53 Mutation Carriers, Emily A. Parham

Dissertations and Theses (Open Access)

Li-Fraumeni syndrome (LFS) is a hereditary cancer predisposition syndrome caused by heterozyogous germline mutations in the TP53 gene and characterized by an excess of early-onset cancers, high lifetime risk of cancer, and a wide range of tumor types. Recent studies suggesting a benefit in comprehensive screening protocols for both children and adults make the timely identification of individuals with LFS increasingly important.

A number of criteria have been proposed to identify patients with LFS. The National Comprehensive Cancer Network (NCCN) combines several in its Clinical Practice Guidelines for TP53 genetic testing. Prior studies have shown that the cumulative sensitivity of …

Cancers Associated With Brca1 And Brca2 Mutations Other Than Breast And Ovarian, Jacqueline Mersch

Dissertations and Theses (Open Access)

Mutations in BRCA1 and BRCA2 cause tumor development in Hereditary Breast and Ovarian Cancer syndrome (HBOC) through accumulation of unrepaired DNA damage. Extensive research of BRCA1 and BRCA2 mutations has led to well-defined breast and ovarian cancer risks in individuals with HBOC. Previous studies have reported additional cancers associated with BRCA mutations; however, the type of cancer, magnitude of risk, and differences between sexes remains to be clarified. Ultimately, a consensus of additional cancer risks can aid in better recommendations for genetic testing and more effective screening and prevention guidelines.

A retrospective chart review of MD Anderson Cancer Center patients …

Latinas And The Traditional Genetic Counseling Model: A Qualitative Study, Stephanie Thompson

Dissertations and Theses (Open Access)

The traditional genetic counseling model reflects an individualized counseling session that includes the presentation of information about genes, chromosomes, personalized risk assessment, and genetic testing and screening options. Counselors are challenged to balance providing educational information with discussion of implications of this information in an allotted amount of time. The aim of this study was to explore the perceptions of pregnant Latinas on the benefits and limitations of the traditional prenatal genetic counseling model and to determine the specific preferences for receiving prenatal genetic counseling. Data were collected through focus groups and one-on-one, semi-structured interviews of twenty-five Spanish speaking Latinas …

Effects Of Creosote-Contaminated Sediment Extracts On Mouse Macrophage Physiology And Function, Rayna Silva

All Theses

The southern branch of the Elizabeth River, at Portsmouth Virginia is one of the most polluted systems in North America. This harbor estuary system is also home to the Atlantic Wood Superfund site, which is heavily contaminated with creosote from the Atlantic Wood (AW) preservative company that ceased production in the later 1990s. Creosote is a mixture of polyaromatic hydrocarbons (PAHs), metals, and numerous aliphatic hydrocarbons, and well known to be carcinogenic. The toxicity of sediments and pore waters from the AW site has been studied extensively using Fundulus heteroclitus, also known as the mummichog, or Atlantic killifish. Most adult …

Extracellular Ubiquitin: Role In Cardiac Myocyte Apoptosis And Myocardial Remodeling, Christopher Ray Daniels

Electronic Theses and Dissertations

Activation of sympathetic nervous system is a key component of myocardial remodeling that generally occurs following ischemia/reperfusion (I/R) injury and myocardial infarction. It induces cardiac myocyte apoptosis and myocardial fibrosis, leading to myocardial dysfunction. Intracellular ubiquitin (UB) regulates protein turnover by the UB-proteosome pathway. The biological functions of extracellular UB in the heart remain largely unexplored. Previously, our lab has shown that β-adrenergic receptor (β-AR) stimulation increases extracellular UB levels, and extracellular UB inhibits β-AR-stimulated apoptosis in adult rat ventricular myocytes (ARVMs). This study explores the role of extracellular UB in myocyte apoptosis, fibroblast phenotype and function, and myocardial remodeling …

Novel Therapeutic Approaches For Ischemic Heart And Brain Injury: Modulation Of Toll-Like Receptor-Mediated Signaling Pathways And Pi3k/Akt Signaling, Chen Lu

Electronic Theses and Dissertations

Innate immune and inflammatory responses contribute to myocardial and cerebral ischemia/reperfusion (I/R) injury. Toll-like receptors (TLRs) play a critical role in the induction of innate immune and inflammatory responses via activation of nuclear factor kappa B (NF-κB). We have shown that activation of NF-κB contributes to myocardial and cerebral I/R injury. Indeed, inhibition of TLR4-mediated NF-κB activation significantly decreased myocardial and cerebral I/R injury via activation of PI3K/Akt signaling. PI3K/Akt signaling is an important pathway in regulating cellular survival and inflammatory responses. Therefore, an important question is how to differentially modulate PI3K/Akt signaling and TLR/NF-κB-mediated signaling pathway during I/R injury? …

9-Phenanthrol And Flufenamic Acid Inhibit Calcium Oscillations In Hl-1 Mouse Cardiomyocytes, Rees A. Burt

Undergraduate Honors Theses

Electrical potentials exist across the membranes of nearly every cell type in the body. In addition, excitable cells, such as neurons, myocytes and even some endocrine cells elicit electrochemical fluctuations, action potentials (AP), in the cell membrane to initiate cell-to-cell communication or intracellular processes. The basis for the electrical potential is rooted within an array of complex interactions between monovalent ions and their associated membrane channels and transporters that regulate the flux of these charged species across the hydrophobic bilayer. Here, an expansion of our recently published work [1] will serve to explore the modern concepts regarding the …

Lrh1 As A Driving Factor For Cancer Development, Alissa M. Margraf

Senior Honors Projects

LRH1 as a driving factor for cancer development

Alissa Margraf, Qi Tang, Qiushi Lin, Xiaoqun Dong

Department of Biomedical and Pharmaceutical Science, College of Pharmacy, The University of Rhode Island, Pharmacy Building, 7 Greenhouse Road, Kingston, RI 02881 USA

Cancer is a major public health problem worldwide. Colon cancer ranks as the third most common causes of cancer mortality in the United States, with an estimated 96,830 new cases and 50,310 deaths in 2014. Colon cancer develops in the digestive tract where benign growths called polyps transform into malignant tumors. Colon cancer cells invade and destroy nearby tissue and can …

Role Of Membrane Fusion Protein Ykt6 In Regulating Epithelial Cell-Cell And Cell-Matrix Adhesions., Supriya Joshi

Theses and Dissertations

Intercellular junctions and cell-matrix adhesions play important roles in the maintenance of epithelial integrity. Assembly and remodeling of the plasma membrane complexes are regulated by membrane trafficking and fusion. This thesis is aimed to elucidate the roles of an important membrane fusion protein, Ykt6, in the regulation of epithelial cell adhesion and migration. For the first time, we show that Ykt6 is essential for assembly of adherens junctions and tight junctions in human prostate epithelial cells. We also observed that Ykt6 negatively regulates both collective epithelial cell migration and cell invasion into Matrigel. The effects of YKT6 on epithelial junctions …

Molecular Characterization Of Glioblastoma Cancer Stem Cells, Jo Meagan Garner

Theses and Dissertations (ETD)

Malignant gliomas are locally aggressive, highly vascular tumors that have an overall survival time less than 14 months, and current therapies provide little improvement in the disease course and outcome. While glioblastoma multiforme (GBM) patients present uniform histological phenotypes, the molecular determinants of the disease vary considerably between individual cases resulting in complicated prognosis. The heterogeneity, aggressiveness and rapid tumor relapse of GBM is believed to be sustained by cancer stem-like cell populations that are able to initiate and maintain tumors. Although CSCs represent only a small fraction of cells within a tumor, their high tumor-initiating capacity and therapeutic resistance …

Preliminary Study On How Tumor Suppressor Nf2 Inhibits Transcriptional Coactivators Yap/Taz In The Developing Mouse Brain, Yu He

Theses and Dissertations (ETD)

Normal brain development requires precise coordination of neural progenitor proliferation and differentiation, the mechanism of which is not well known. Recently the tumor suppressor neurofibromatosis 2 (Nf2) was shown to regulate the balance of neural progenitor proliferation and differentiation in the developing mouse brain through the Hippo pathway effectors, transcriptional coactivators Yap/Taz. The molecular mechanism of how Nf2 regulates Yap/Taz is not understood. Here I showed that Nf2 regulated the Yap/Taz activity by decreasing the stability of Yap/Taz. The regulation was independent of Yap-S366 phosphorylation, which is required for Yap degradation. I also showed that Nf2 did not regulate Lats1/2 …

Characterization Of Cre Mouse Models To Target Cns Barriers For Generating Conditional Knockouts Of Abc Transporters, Rachel L. Scheib

Theses and Dissertations (ETD)

The central nervous system (CNS) includes the brain and spinal cord, where both possess a blood to brain and a blood to cerebrospinal fluid (CSF) barrier. The blood-brain barrier (BBB) and blood-CSF barrier (BCSFB) regulate the passage of many molecules to maintain and protect these sensitive organs from harmful xenobiotics (i.e. drugs, pollutants, etc.) or physiologic changes (i.e. glucose, ion, or water composition). These barriers also express ABC transporters, including P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP), which are known to contribute to efflux of endogenous toxins and therapeutics from the CNS. Pgp and BCRP expression and activity are …

Adenosine Production Is Essential For Closing The Critical Period Of Cortical Plasticity, Rachel A. Chassan

Theses and Dissertations (ETD)

Sensory inputs from the external world are represented as highly organized systems in the adult brain for effective adaptation to the environment. At the cortical level, this organization is referred to as cortical maps. The establishment of cortical maps begins with early life experiences during the critical period, a brief period during development of heightened sensitivity to sensory stimuli. During this time, organization of cortical maps is plastic and highly subject to change through passive sensory experience. As an animal matures, the critical period closes and changes to cortical maps occur less freely. The cellular mechanisms of cortical map plasticity …

Predicting Targeted Drug Combinations Based On Pareto Optimal Patterns Of Coexpression Network Connectivity, Nadia M. Penrod, Casey S. Greene, Jason H. Moore

Dartmouth Scholarship

Molecularly targeted drugs promise a safer and more effective treatment modality than conventional chemotherapy for cancer patients. However, tumors are dynamic systems that readily adapt to these agents activating alternative survival pathways as they evolve resistant phenotypes. Combination therapies can overcome resistance but finding the optimal combinations efficiently presents a formidable challenge. Here we introduce a new paradigm for the design of combination therapy treatment strategies that exploits the tumor adaptive process to identify context-dependent essential genes as druggable targets. We have developed a framework to mine high-throughput transcriptomic data, based on differential coexpression and Pareto optimization, to investigate drug-induced …

Suppression Of Basophil Histamine-Release And Other Ige-Dependent Responses In Childhood Schistosoma Mansoni Hookworm Co-Infection, Angela Pinot De Moira, Colin M. Fitzsimmons, Frances M. Jones, Shona Wilson, Pierre Cahen, Edridah Tukahebwa, Harriet Mpairwe, Joseph K. Mwatha, Jeffrey M. Bethony, Per S. Skov, Narcis B. Kabatereine, David W. Dunne

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background. The poor correlation between allergen-specific-IgE (asIgE) and clinical signs of allergy in helminth infected populations suggests that helminth infections could protect against allergy by uncoupling asIgE from its effector mechanisms. We investigated this hypothesis in Ugandan schoolchildren coinfected with Schistosoma mansoni and hookworm.

Methods. Skin prick test (SPT) sensitivity to house dust mite allergen (HDM) and current wheeze were assessed pre-anthelmintic treatment. Non-specific (anti-IgE), helminth-specific and HDM-allergen-specific basophil histamine release (HR), plus helminth- and HDM-specific IgE and IgG4 responses were measured pre- and post-treatment.

Results. Non-specific- and helminth-specific-HR, and associations between helminth-specific-IgE and helminth-specific-HR increased post-treatment. Hookworm infection appeared …

Tumor Microenvironment-Based Feed-Forward Regulation Of Nos2 In Breast Cancer Progression, Julie L. Heinecke, Lisa A. Ridnour, Robert Y.S. Cheng, Christopher H. Switzer, Michael M. Lizardo, Chand Khanna, Sharon A. Glynn, S. Perwez Hussain, Howard A. Young, Stefan Ambs, David A. Wink

United States Public Health Resources

Inflammation is widely recognized as an inducer of cancer progression. The inflammation-associated enzyme, inducible nitric oxide synthase (NOS2), has emerged as a candidate oncogene in estrogen receptor (ER)-negative breast cancer, and its increased expression is associated with disease aggressiveness and poor survival. Although these observations implicate NOS2 as an attractive therapeutic target, the mechanisms of both NOS2 induction in tumors and nitric oxide (NO)-driven cancer progression are not fully understood. To enhance ourmechanistic understanding of NOS2 induction in tumors and its role in tumor biology, we used stimulants of NOS2 expression in ER- and ER+ breast cancer cells and examined …

Avirulent Strains Of Toxoplasma Gondii Infect Macrophages By Active Invasion From The Phagosome, Yanlin Zhao, Andrew H. Marple, David J. P. Ferguson, David J. Bzik, George S. Yap

Dartmouth Scholarship

Unlike most intracellular pathogens that gain access into host cells through endocytic pathways, Toxoplasma gondii initiates infection at the cell surface by active penetration through a moving junction and subsequent formation of a parasitophorous vacuole. Here, we describe a noncanonical pathway for T. gondii infection of macrophages, in which parasites are initially internalized through phagocytosis, and then actively invade from within a phagosomal compartment to form a parasitophorous vacuole. This phagosome to vacuole invasion (PTVI) pathway may represent an intermediary link between the endocytic and the penetrative routes for host cell entry by intracellular pathogens. The PTVI pathway is preferentially …

The Roles Of Krüppel-Like Transcription Factors Klf1 And Klf2 In Mouse Embryonic And Human Fetal Erythropoiesis, Divya Vinjamur

Theses and Dissertations

Hemoglobinopathies are some of the most common monogenic disorders in the world, affecting millions of people and representing a growing burden on health systems worldwide. Although the pathophysiology of sickle cell anemia and beta-thalassemia, two of the most common hemoglobinopathies, have been the focus of much research over the last century, patients affected by these diseases still lack a widely applicable and easily available cure. Sickle cell anemia and beta-thalassemia are caused by defects in the structure and production of the beta-globin chains that, along with the alpha-globin chains make up the heterotetrameric hemoglobin molecule. Studies geared towards re-expression of …

The Microbiome In Pediatric Cystic Fibrosis Patients: The Role Of Shared Environment Suggests A Window Of Intervention, Thomas H. Hampton, Deanna M. Green, Garry R. Cutting, Hilary G. Morrison, Mitchell L. Sogin, Alex H. Gifford, Bruce A. Stanton, George A. O’Toole

Dartmouth Scholarship

Cystic fibrosis (CF) is caused by mutations in the CFTR gene that predispose the airway to infection. Chronic infection by pathogens such as Pseudomonas aeruginosa leads to inflammation that gradually degrades lung function, resulting in morbidity and early mortality. In a previous study of CF monozygotic twins, we demonstrate that genetic modifiers significantly affect the establishment of persistent P. aeruginosa colonization in CF. Recognizing that bacteria other than P. aeruginosa contribute to the CF microbiome and associated pathology, we used deep sequencing of sputum from pediatric monozygotic twins and nontwin siblings with CF to characterize pediatric bacterial communities and the …

Hydration Status And Performance During Two-A-Day Summer Soccer Training Sessions With Female Athletes, Kristina Burk

Celebrating Scholarship & Creativity Day (2011-2017)

No abstract provided.