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The Role Of E-Liquid Constituents In E-Cigarette-Induced Cardiac Arrhythmia And Autonomic Imbalance., Cory Kucera Aug 2023

The Role Of E-Liquid Constituents In E-Cigarette-Induced Cardiac Arrhythmia And Autonomic Imbalance., Cory Kucera

Electronic Theses and Dissertations

Introduction. Accumulating evidence indicates that exposure to electronic cigarettes (e-cigs) promotes sympathetic dominance and electrophysiologic instability in the heart, potentially culminating in arrhythmogenesis. E-liquids contain various formulations of nicotine and flavorings, but the effects of specific e-liquid constituents and their concentrations on e-cig-induced autonomic imbalance and electrical dysfunction are unresolved. To that end, we tested the hypothesis that e-cigs modify cardiac autonomic balance and ventricular arrhythmogenesis in mice dependent on e-liquid constituent type and concentration. Methods. Using a crossover design and a serial exposure regimen, ECG-telemetered male C57BL/6J mice underwent whole-body exposure to e-cig aerosols generated from e-liquids containing different …


Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan May 2022

Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan

Electronic Theses and Dissertations

Retinal fibrosis is detrimental to vision. Retinal pigment epithelial (RPE) cells contribute to several retinal fibrotic diseases. Upon exposure to TGF-β, a key fibrotic cytokine, RPE cells trans-differentiate to myofibroblasts marked by the integration of α-SMA fibers into F-actin stress fibers, which confer strong contractility. Myofibroblasts produce and contract the collagen-rich fibrotic scar and disrupt retinal architecture. In this study, we investigated the in vitro effects of the putative endocannabinoid compound N-oleoyl dopamine (OLDA) on TGF-β2 induced porcine RPE cell contraction and α-SMA expression. Using an in vitro collagen matrix contraction assay, we found that OLDA inhibited TGF-β2 induced contraction …


Identifying The Cardiovascular Effects Of Multiple Pollutants., Katlyn Elizabeth Mcgraw May 2021

Identifying The Cardiovascular Effects Of Multiple Pollutants., Katlyn Elizabeth Mcgraw

Electronic Theses and Dissertations

Cardiovascular disease (CVD) is the leading cause of death from environmental exposures. Although exposure to PM2.5 is an established risk factor for CVD, the contribution of other hazardous pollutant exposure to CVD is less clear. Overall, this work aimed to examine the effect of pollutants with lesser documented effects on cardiovascular disease using a multi-pronged approach to exposure assessment. The three aims were to examine the relationship between county-level toxic chemical releases and CVD mortality in the contiguous United States between 2002 and 2012, to assess the relationship between individual-level VOC metabolites and vascular function, and to build multipollutant …


N-Acetyltranserase 2 (Nat2) Genotype Polymorphism In Cryopreserved Human Hepatocytes And Chinese Hamster Ovary (Cho) Cells., Mariam Refaat Zaky Habil Aug 2020

N-Acetyltranserase 2 (Nat2) Genotype Polymorphism In Cryopreserved Human Hepatocytes And Chinese Hamster Ovary (Cho) Cells., Mariam Refaat Zaky Habil

Electronic Theses and Dissertations

Arylamine N-acetyltransferases, NAT1 and NAT2, catalyze the detoxification and/or activation of drugs and aromatic amine carcinogens. Single nucleotide polymorphisms or SNPs result in different human NAT2 genotypes thus dividing the population into rapid, intermediate, and slow acetylators. We hypothesize allelic variants of NAT2 genotype will decrease levels of N-acetylation, cytotoxicity, oxidative stress, DNA adduct formation, and mutagenesis compared to the reference allele NAT2*4. Cryopreserved human hepatocytes expressing different NAT2 genotypes and NER-deficient Chinese hamster ovary (CHO) cells transfected with human CYP1A2 and human NAT2*4, NAT2*5B or NAT2*7B have been used to investigate N-acetylation of different xenobiotics. In …


Volatile Organic Compound Exposure And Cardiometabolic Syndrome Risk In A Nationally Representative Cohort., Stacey Lane Konkle May 2020

Volatile Organic Compound Exposure And Cardiometabolic Syndrome Risk In A Nationally Representative Cohort., Stacey Lane Konkle

Electronic Theses and Dissertations

BACKGROUND: The relative importance of environmental exposures such as volatile organic compounds (VOCs) is one of the paramount public health priorities of our time, yet is presently unstudied. VOCs are ubiquitous in the environment and have been associated with numerous adverse health effects, including a number of cardiovascular and metabolic effects that are components of Cardiometabolic Syndrome (CMS). OBJECTIVES: To examine the relationship between CMS and individual-level exposures to VOCs, measured as urinary metabolites of VOCs (UM-VOCs), in a nationally representative sample. METHODS: Associations between urinary biomarkers of exposure to 19 parent VOCs and CMS were assessed using the National …


Tobacco-Derived Aldehydes: Platelet Activation, Thrombosis, And The Role Of Trpa1., Andre Dwayne Richardson May 2020

Tobacco-Derived Aldehydes: Platelet Activation, Thrombosis, And The Role Of Trpa1., Andre Dwayne Richardson

Electronic Theses and Dissertations

Cigarette smoking is the single largest risk factor for cardiovascular disease (CVD) pathophysiology. Numerous researchers have shown potential associations between aldehydes in tobacco-derived aerosols from mainstream cigarette smoke (MCS) or electronic cigarettes (e-cigs) and their cardiotoxicity by damaging blood vessel endothelium. The severity of exposure to these toxicants can furthermore lead to adverse cardiovascular outcomes such as myocardial infarctions, stroke, coronary and peripheral artery disease, or atherosclerosis due to blood clots, a pro-thrombotic event. However, the mechanisms by which levels of harmful and potentially harmful constituents (HPHCs) such as aldehydes induce thrombosis are not well-known. Of specific interest, evidence has …


Tobacco Product-Derived Aldehydes: Effects On Circulating Angiogenic Cells & Implications For Cardiovascular Disease., Jordan B. Lynch May 2020

Tobacco Product-Derived Aldehydes: Effects On Circulating Angiogenic Cells & Implications For Cardiovascular Disease., Jordan B. Lynch

Electronic Theses and Dissertations

Cardiovascular disease (CVD) is the leading cause of death worldwide. Tobacco smoke is the most significant modifiable risk factor in CVD development and contains numerous toxic compounds, including aldehydes, which have been linked to CVD. Formaldehyde, acetaldehyde, acrolein, and crotonaldehyde have been identified as significant contributors to cigarette-induced health effects, but the mechanism of these effects is not well understood. These aldehydes are also found in aerosols produced by e-cigarettes (e-cigs). The goal of this dissertation was to explore the systemic, hematological, and endothelium-related effects of exposure to tobacco products and constituent aldehydes and to identify potential mechanisms of injury. …


The Role Of Slc7a11 In Controlling Extracellular And Intracellular Redox Environments Of Lung Fibroblasts - Potential Targets For Intervention In Aging And Idiopathic Pulmonary Fibrosis., Yuxuan Zheng May 2020

The Role Of Slc7a11 In Controlling Extracellular And Intracellular Redox Environments Of Lung Fibroblasts - Potential Targets For Intervention In Aging And Idiopathic Pulmonary Fibrosis., Yuxuan Zheng

Electronic Theses and Dissertations

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease characterized by extracellular matrix deposition by fibroblasts. Aging and oxidative stress increase the susceptibility to IPF. Redox couples, cysteine/cystine (Cys/CySS) and glutathione/glutathione disulfide (GSH/GSSG), and their redox potentials (Eh) quantify oxidative stress. Fibroblasts from old mice maintain more oxidized extracellular Eh(Cys/CySS) than young mice. Microarray shows down-regulation of Slc7a11 potentially mediates this age-related oxidation. Slc7a11 is the key component of system Xc-, an antiporter that imports CySS and exports glutamate. The first aim of this dissertation is to investigate the mechanistic link between Slc7a11 …


Dual Role Of Antimicrobial Peptide Cathelicidin In Alcohol-Associated Liver Disease., Fengyuan Li May 2020

Dual Role Of Antimicrobial Peptide Cathelicidin In Alcohol-Associated Liver Disease., Fengyuan Li

Electronic Theses and Dissertations

Patients with alcohol-associated liver disease (ALD) have high morbidity and mortality in its severe forms. One of the major features in different forms of ALD is the altered gut microbiota. Antimicrobial peptides (AMPs) play a crucial role in maintaining gut microbiota homeostasis. LL-37 (known as CRAMP in mouse) is the sole member of the human cathelicidin family and has piqued great research interest for its dual role in modulating microbiota and the immune response in metabolic diseases. Inflammasome activation is an important component of the liver pathophysiology in ALD and requires two signals for its full activation to induce the …


Development Of Bar-Peptide Nanoparticles And Electrospun Fibers For The Prevention And Treatment Of Oral Biofilms., Mohamed Yehia Mahmoud May 2019

Development Of Bar-Peptide Nanoparticles And Electrospun Fibers For The Prevention And Treatment Of Oral Biofilms., Mohamed Yehia Mahmoud

Electronic Theses and Dissertations

Background: Periodontal diseases are globally prevalent inflammatory disorders that affect ~47% of U.S adults. Porphyromonas gingivalis (Pg) has been identified as a “keystone” pathogen that disrupts host-microbe homeostasis and contributes to the initiation and progression of periodontitis. Pg associates with oral streptococci in supragingival plaque and this interaction represents a potential target for therapeutic intervention. Previously our group developed a peptide (designated BAR), that potently inhibits Pg/Streptococcus gordonii (Sg) adherence in vitro and Pg virulence in a murine model of periodontitis. While efficacious, BAR (SspB Adherence Region) provided transient inhibition and required higher concentrations of BAR to disrupt established …


Development Of A Lectin-Fc Fusion Protein With Antiviral And Anti-Cancer Activity., Matthew William Dent May 2019

Development Of A Lectin-Fc Fusion Protein With Antiviral And Anti-Cancer Activity., Matthew William Dent

Electronic Theses and Dissertations

This thesis describes the development of a novel lectin-Fc fusion protein and its antiviral and anti-cancer activity. The molecule, Avaren-Fc (AvFc), is a fusion of a variant of the actinomycete lectin actinohivin (Avaren) and the Fc region of human IgG1, and is selective for the terminal α1,2-mannose residues found at the ends of high-mannose-type glycans that can be found on the surface of certain heavily glycosylated viruses and cancer cells. Here, AvFc was found to be able to neutralize simian immunodeficiency virus as well as Hepatitis C virus with nanomolar IC50 values. Furthermore, AvFc recognizes a number of cell …


Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller Aug 2018

Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller

Electronic Theses and Dissertations

The inherent heterogeneity of tumor tissue presents a major challenge to nanoparticle-medicated drug delivery. This heterogeneity spans from the molecular to the cellular (cell types) and to the tissue (vasculature, extra-cellular matrix) scales. Here we employ computational modeling to evaluate therapeutic response as a function of vascular-induced tumor tissue heterogeneity. Using data with three-layered gold nanoparticles loaded with cisplatin, nanotherapy is simulated with different levels of tissue heterogeneity, and the treatment response is measured in terms of tumor regression. The results show that tumor vascular density non-trivially influences the nanoparticle uptake and washout, and the associated tissue response. The drug …


Wnt/Β-Catenin Mediated Cancer Stem Cell Activation In Hepatocellular Carcinoma., Harshulkumar M. Pandit Aug 2018

Wnt/Β-Catenin Mediated Cancer Stem Cell Activation In Hepatocellular Carcinoma., Harshulkumar M. Pandit

Electronic Theses and Dissertations

Hepatocellular carcinoma (HCC) is one of the deadliest cancers, with variable presentation, high chemotherapy resistance and early tumor recurrence. In this dissertation, we have systematically enriched, identified and characterized HCC cancer stem cells (CSCs) from 3 different HCC cell lines (Hepa1-6, HepG2, and Hep3B) using in vitro serum-free culture method. Enriched spheroids acquired CSC properties, primarily self-renewal capability, spheroid formation ability, and drug resistance. Heterogeneous CSCs enriched from Hepa1-6 cells demonstrated higher tumor initiation and proliferation capability in vivo, compared to control HCC cells in orthotopic immunocompetent mouse model. EpCAM+ CSCs were significantly enriched within heterogeneous Hepa1-6 CSC spheroids. Consequently, …


A Novel Fibroblast Growth Factor 1 Variant Reverses Nonalcoholic Fatty Liver Disease In Type 2 Diabetes., Qian Lin Aug 2018

A Novel Fibroblast Growth Factor 1 Variant Reverses Nonalcoholic Fatty Liver Disease In Type 2 Diabetes., Qian Lin

Electronic Theses and Dissertations

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder and is strongly associated with type 2 diabetes (T2D). Our recently engineered FGF1 partial agonist, carrying triple mutations (FGF1HBS) exhibits greatly reduced proliferative potential, while preserving the full metabolic activity of wild-type FGF1. This study tests the preventive and therapeutic effects of FGF1HBS on NAFLD in db/db T2D and explores potential mechanisms. The results showed that administration of FGF1HBS to 2-month-old db/db mice for 2 months constantly lowered blood glucose levels, improved insulin sensitivity, and lowered liver weight, lipid deposition, and …


Deciphering The Role Of Human Arylamine N-Acetyltransferase 1 (Nat1) In Breast Cancer Cell Metabolism Using A Systems Biology Approach., Samantha Marie Carlisle Aug 2018

Deciphering The Role Of Human Arylamine N-Acetyltransferase 1 (Nat1) In Breast Cancer Cell Metabolism Using A Systems Biology Approach., Samantha Marie Carlisle

Electronic Theses and Dissertations

Background: Human arylamine N-acetyltransferase 1 (NAT1) is a phase II xenobiotic metabolizing enzyme found in almost all tissues. NAT1 can additionally hydrolyze acetyl-coenzyme A (acetyl-CoA) in the absence of an arylamine substrate. NAT1 expression varies inter-individually and is elevated in several cancers including estrogen receptor positive (ER+) breast cancers. Additionally, multiple studies have shown the knockdown of NAT1, by both small molecule inhibition and siRNA methods, in breast cancer cells leads to decreased invasive ability and proliferation and decreased anchorage-independent colony formation. However, the exact mechanism by which NAT1 expression affects cancer risk and progression remains unclear. Additionally, consequences …


The Effects Of Polychlorinated Biphenyls Exposure On Non-Alcoholic Fatty Liver Disease : Role Of Aryl Hydrocarbon Receptor., Hongxue Shi May 2018

The Effects Of Polychlorinated Biphenyls Exposure On Non-Alcoholic Fatty Liver Disease : Role Of Aryl Hydrocarbon Receptor., Hongxue Shi

Electronic Theses and Dissertations

Polychlorinated biphenyls (PCBs) are detectable in serum of 100% of adults in US, and has been associated with fatty liver disease in epidemiological studies. PCBs are classified as either dioxin-like (DL) or non-dioxin-like (NDL) PCB based on their ability to activate the aryl hydrocarbon receptor (AhR). We used exposures that reflect human bioaccumulation patterns, which resembles Aroclor 1260 with a low level of the DL-PCB, PCB 126. Our aim was to determine if this exposure will activate the human and mouse AhR and examine if receptor activation influences these steatotic responses due to PCB exposures. DL-PCBs exposure-induced AhR activation in …


Air Pollution, Pulmonary Oxidative Stress, And The Endothelin System In The Development Of Cardiovascular Injury., Jordan B. Finch Aug 2016

Air Pollution, Pulmonary Oxidative Stress, And The Endothelin System In The Development Of Cardiovascular Injury., Jordan B. Finch

Electronic Theses and Dissertations

The goal of this project was to examine the role of endothelin-1 (ET-1) as a mediator in the pathway between air pollution exposure and the development of vascular injury. A human cohort and male mice (C57BL/6 and ecSOD-Tg) were used to evaluate changes in the ET-1 system in response to exposures of fine particulate matter (PM2.5). Human ET-1 levels were significantly associated with environmental factors and markers of vascular change, but were decreased with increased PM2.5. No association was seen between ET-1 and endothelial progenitor cells (EPCs) except for EPC-4, possibly indicating a regulatory relationship with this specific population. In …


Mechanisms And Intervention Strategies For Alcohol And Hiv-Antiretroviral Therapy-Induced Liver Injury., Hridgandh Donde Dec 2015

Mechanisms And Intervention Strategies For Alcohol And Hiv-Antiretroviral Therapy-Induced Liver Injury., Hridgandh Donde

Electronic Theses and Dissertations

Chronic alcohol consumption is a leading cause of liver disease and liver-related death worldwide. Alcoholic liver disease includes, hepatic steatosis, steatohepatitis and ultimately fibrosis and cirrhosis. Emerging evidence has established the important role of the “gut-liver” axis in the development of alcoholic liver disease (ALD). Our recent work indicated that chronic alcohol induced perturbations in the gut microbiome and consequent changes in fatty acids have a major impact on the development of intestinal barrier dysfunction and ALD. The aim of this study was to investigate whether treatment with tributyrin - a butyrate prodrug results in protection against ALD in terms …