Medicine and Health Sciences Commons^™

Role Of Angiotensin Converting Enzyme 2 (Ace2) In Obesity-Associated Hypertension, Manisha Gupte

University of Kentucky Doctoral Dissertations

The purpose of this research was to determine whether adipocytes express ACE2 and its role in obesity-associated hypertension with diet-induced obesity.

To determine if ACE2 was expressed in adipose tissue and its regulation in the setting of diet-induced obesity, we fed male mice either a low fat (LF) or high fat (HF) diet acutely (1 week) or chronically ( 4 months). We demonstrated that ACE2 was regulated specifically in adipose tissue with consumption of a HF diet. However, with chronic HF feeding adipose ACE2 was dysregulated resulting in activation of the systemic RAS and increased blood pressure.

To determine the …

Genotoxin-Induced Acetylation Of The Werner Syndrome Protein (Wrn) And Effect On Its Dna Metabolic Function, Enerlyn Meliza Lozada Santiago

University of Kentucky Doctoral Dissertations

Loss of function of the WRN protein causes the genetic disorder Werner Syndrome that is characterized by increased cancer and premature aging. WRN belongs to the RecQ helicase family that plays key roles in preventing genome instability. In response to treatment with genotoxins, WRN is subject to post-translational modification. The relationship of post-translational modification of WRN with its function in DNA metabolism is unknown. There is accumulating evidence suggesting that WRN contributes to the maintenance of genomic integrity through its involvement in DNA replication. Consistent with this notion, WS cells are sensitive to DNA replication inhibitors and DNA damaging agents …

Identification Of Activities Involved In Cag/Ctg Repeat Instability, Nelson Lap Shun Chan

University of Kentucky Doctoral Dissertations

CAG/CTG repeat instability is associated with at least 14 neurological disorders, including Huntington’s disease and Myotonic dystrophy type 1. In vitro and in vivo studies have showed that CAG/CTG repeats form a stable hairpin that is believed to be the intermediate for repeat expansion and contraction.

Addition of extra DNA is essential for repeat expansion, so DNA synthesis is one of the keys for repeat expansion. In vivo studies reveal that 3’ CTG slippage with subsequent hairpin formation (henceforth called the 3’ CTG slippage hairpin) occurs during DNA synthesis. It is proposed that hairpin tolerance machinery is activated because prolonged …

Post-Transcriptional Regulation Of Afp And Igm Genes, Lilia M. Turcios

University of Kentucky Doctoral Dissertations

Gene expression can be regulated at multiple steps once transcription is initiated. I have studied two different gene models, the α-Fetoprotein (AFP) and the immunoglobulin heavy chain (IgM) genes, to better understand post-transcriptional gene regulation mechanisms. The AFP gene is highly expressed during fetal liver development and dramatically repressed after birth. There is a mouse strain-specific difference between adult levels of AFP, with BALB/cJ mice expressing 10 to 20-fold higher levels compared to other mouse strains. BALB/cJ mice express low levels of Zhx2 and thus incompletely repress AFP. Despite differences in steady state AFP mRNA levels in the adult liver …

Computational Analyses Of The Uptake And Distribution Of Carbon Monoxide (Co) In Human Subjects, Kinnera Chada

University of Kentucky Doctoral Dissertations

Carbon monoxide (CO) is an odorless, colorless, tasteless gas that binds to hemoglobin with high affinity. This property underlies the use of low doses of CO to determine hemoglobin mass (M_Hb) in the fields of clinical and sports medicine. However, hemoglobin bound to CO is unable to transport oxygen and exposure to high CO concentrations is a significant environmental and occupational health concern. These contrasting aspects of CO—clinically useful in low doses but potentially lethal in higher doses—mandates a need for a quantitative understanding of the temporal profiles of the uptake and distribution of CO …

Novel Mechanisms In Inflammatory Bowel Disease, Razvan I. Arsenescu

University of Kentucky Doctoral Dissertations

Inflammatory Bowel Diseases, Crohn's Disease and Ulcerative colitis, are idiopathic chronic conditions with multifactorial determinants. In general, terms, intestinal inflammation results from abnormal host-microbe interactions. Alterations in homeostasis involve host genetic factors, environmental cues and unique luminal microbial niches. We have examined the coordinated expressions of several molecular targets relevant to the mucosal immune system and identified signature biomarkers of IBD. Qualitative and quantitative changes in the composition of microbiota can be related to unique immuno-phenotypes. This in turn can have more systemic effects that involve energy metabolism. Adiponectin, an adipose tissue derived adipokine, can restore cellular ATP levels and …

Androgen Increases Angiotensin Receptor Type 1a On Smooth Muscle Cells To Promote Angiotensin Ii-Induced Abdominal Aortic Aneurysms, Xuan Zhang

University of Kentucky Doctoral Dissertations

The purpose of this study was to determine whether androgen promotes AT1aR expression on smooth muscle to confer high prevalence of AngII-induced AAAs in hyperlipidemic mice. In addition, we also investigate the role of androgen in the progression of established AngII-induced AAAs.

First, we sought to examine the role of endogenous androgen in the growth of established AngII-induced AAAs. By castrating male mice, we demonstrated that removal of endogenous androgen significantly decreased the progressive lumen dilation of established AngII-induced AAAs in male ApoE-/- mice, but had no effect on external AAA diameters. These results suggest that androgen contributes to the …

Regulation Of Abcg5 And Abcg8 Sterol Transporters In Biliary Cholesterol Elimination, Reverse Cholesterol Transport And Dyslipidemia, Nadezhda Steliyanova Sabeva

University of Kentucky Doctoral Dissertations

ATP-binding cassette transporters ABCA1 and ABCG1 initiate reverse cholesterol transport generating HDL particles, whereas ABCG5/G8 promote biliary cholesterol secretion thereby facilitating the last step of reverse cholesterol transport. Mutations in the leptin axis result in obesity and dyslipidemia in ob/ob and db/db mice. These mice have defective HDL clearance, increased plasma cholesterol and decreased biliary cholesterol elimination. My studies demonstrate that ABCG5/G8 protein is low in these animals and can be restored with caloric restriction or leptin replacement. To directly test whether ABCG5/G8 alone is able to correct reverse cholesterol transport defect, liver specific ABCG5/G8 expression was achieved in db/db …

Factors Associated With Tobacco Use Among Rural And Urban Pregnant Women, Whitney Jeanne Katirai

University of Kentucky Doctoral Dissertations

The purpose of this study was to investigate the influences of smoking on rural and urban pregnant women. More specifically, the variables of the knowledge of health effects, health provider recommendations, subscores from the Health Belief Model (HBM), and social support were explored in relation to the smoking behavior of pregnant women. A secondary purpose was to investigate the accuracy of self-reported smoking during pregnancy using biochemical validation. Pregnant women (N=71) completed an anonymous questionnaire, designed by the researcher, to identify variables that predicted smoking for urban and rural women. Participants also gave a saliva sample for cotinine testing.

Approximately …

Genome-Wide Association Studies At The Interface Of Alzheimer’S Disease And Epidemiologically Related Disorders, Christopher Ryan Simmons

University of Kentucky Doctoral Dissertations

Genome-wide association studies (GWAS)s provide an unbiased means of exploring the landscape of complex genetic disease. As such, these studies have identified genetic variants that are robustly associated with a multitude of conditions. I hypothesize that these genetic variants serve as excellent tools for evaluation of the genetic interface between epidemiologically related conditions. Herein, I test the association between SNPs associated with either (i) plasma lipids, (ii) rheumatoid arthritis (RA) or (iii) diabetes mellitus (DM) and late-onset Alzheimer’s disease (AD) to identify shared genetic variants. Regarding the most significantly AD-associated variants, I have also attempted to elucidate their molecular function. …

Microneedle-Assisted Transdermal Delivery Of Naltrexone Species: In Vitro Permeation And In Vivo Pharmacokinetic Studies, Mikolaj Milewski

University of Kentucky Doctoral Dissertations

Naltrexone (NTX) is a drug used primarily in the management of alcohol dependence and opioid dependence. Based on several drawbacks associated with the oral and injectable intramuscular dosage forms of naltrexone currently available on the market, there is substantial interest in delivering naltrexone transdermally. Although naltrexone does not permeate skin at the rate sufficient to reach therapeutic plasma concentrations in humans, novel flux enhancement methods such as microneedles help address this challenge. Earlier work in humans has demonstrated that the use of microneedles achieves plasma concentrations in the lower end of expected therapeutic values. Further flux enhancement is desired to …

Implementation Effectiveness Of Campus Tobacco-Free Policies, Amanda Fallin

University of Kentucky Doctoral Dissertations

Tobacco use and secondhand smoke exposure are leading causes of preventable morbidity and mortality in the United States. Outdoor tobacco smoke exposure conveys many of the same risks as indoor secondhand smoke exposure. Tobacco-free campuses policies are an intervention to promote a positive social norm that encourages smoking cessation, as well as reduces exposure to outdoor tobacco smoke. This dissertation contains a review of the policy implementation literature; findings from a psychometric analysis of the newly developed Tobacco-free Compliance Assessment Tool (TF-CAT) to assess compliance with tobacco-free campus policies; and results of a campus intervention study to promote compliance. The …

Atomic Force Microscopy Method Development For Surface Energy Analysis, Clare Aubrey Medendorp

University of Kentucky Doctoral Dissertations

The vast majority of pharmaceutical drug products are developed, manufactured, and delivered in the solid-state where the active pharmaceutical ingredient (API) is crystalline. With the potential to exist as polymorphs, salts, hydrates, solvates, and cocrystals, each with their own unique associated physicochemical properties, crystals and their forms directly influence bioavailability and manufacturability of the final drug product. Understanding and controlling the crystalline form of the API throughout the drug development process is absolutely critical. Interfacial properties, such as surface energy, define the interactions between two materials in contact. For crystal growth, surface energy between crystal surfaces and liquid environments not …

Dementia Caregiving Outcomes: The Impact Of Caregiving Onset, Role Occupancy, And Care-Recipient Decline, Katherina Nikzad-Terhune

University of Kentucky Doctoral Dissertations

Dementia is characterized as a progressive loss of brain function that results in the deterioration of many cognitive and physical abilities. Alzheimer’s disease (AD) is the most common form of dementia, causing steady declines in memory, functional abilities, and mental functioning. With a projected increase of degenerative illnesses, such as AD, family caregiving for individuals with the disease is also steadily increasing. Caring for an individual with AD has been characterized as a “career,” and within this career are a number of key transitions, including the onset of caregiving. Preexisting caregiving research reveals a number of negative consequences for AD …

Polyamine Modulation In Alcoholism: Examination Using A Novel Screening Procedure Designed To Predict Anti-Relapse And Neuroprotective Efficacy, J. Ben Lewis

University of Kentucky Doctoral Dissertations

Alcohol dependence is a major public health concern. Despite the FDA’s approval of multiple anti-relapse drugs, relapse rates remain unacceptably high. Furthermore, cognitive deficits among chronic drinkers are evident and are suggested to contribute to relapse risk. Current evidence suggests that several critical features of alcoholism and alcohol-associated neurodegeneration are mechanistically linked to glutamatergic actions; specifically, they appear positively affected by glutamatergic inhibition, particularly inhibition via polyamine modulation of a subpopulation of n-methyl-d-aspartate receptors. The current project was designed to evaluate the performance of two putative polyamine modulators (JR-220 and CP-101,606) in a variety of screens designed …

Isolation And Elucidation Of The Chrysomycin Biosynthetic Gene Cluster And Altering The Glycosylation Patterns Of Tetracenomycins And Mithramycin-Pathway Molecules, Stephen Eric Nybo

University of Kentucky Doctoral Dissertations

Natural products occupy a central role as the majority of currently used antibiotic and anticancer agents. Among these are type-II polyketide synthase (PKS)-derived molecules, or polyketides, which are produced by many representatives of the genus Streptomyces. Some type-II polyketides, such as the tetracyclines and the anthracycline doxorubicin, are currently employed as therapeutics. However, several polyketide molecules exhibit promising biological activity, but due to toxic side effects or solubility concerns, remain undeveloped as drugs.

Gilvocarcin V (GV) (topoisomerase II inhibitor) has a novel mechanism of action: [2+2] cycloaddition to thymine residues by the 8-vinyl side chain and cross-linking of histone …

The Absence Of Abcd2 Reveals A Novel Role For Peroxisomes In The Protection From Metabolic Syndrome, Jingjing Liu

University of Kentucky Doctoral Dissertations

ABCD2 (D2) is a peroxisomal ATP binding cassette (ABC) transporter that is expressed in brain, adrenal and liver. D2 is transcriptionally regulated by key transcriptional factors that control lipid and glucose metabolism. Therefore, we examined its role in adipose tissue. These studies revealed that D2 is highly abundant in adipose tissue and upregulated during adipogenesis. However, D2 deficiency does not affect either adipogenesis or lipid accumulation. An examination of the lipid profile of adipose tissue revealed the accumulation of C20 and C22 fatty acids in D2 deficient (D2‐/‐) mice. When challenged with a diet enriched in erucic acid (C22:1, 10% …

Traumatic Brain Injury: Cyclophilin D As A Therapeutic Target And The Neuropathology Caused By Blast, Ryan Douglas Readnower

University of Kentucky Doctoral Dissertations

With an estimated incidence of 1.5 million each year, traumatic brain injury (TBI) is a major cause of mortality and morbidity in the United States. Opening of the mitochondrial permeability transition pore (mPTP) is a key event contributing to TBI pathology. Cyclophilin D (CypD), a matrix peptidyl-prolyl cis-trans isomerase, is believed to be the regulating component of the mPTP. Cyclosporin A, an immunosuppressant drug, inhibits CypD and blocks mPTP formation and has been shown to be neuroprotective following TBI. However, it is unclear if CsA’s neuroprotective mechanism is due to inhibition of CypD and/or immuno-suppression. Therefore to directly assess the …

Intrapsychic Predictors Of Professional Quality Of Life: Mindfulness, Empathy, And Emotional Separation, Jacky T. Thomas

University of Kentucky Doctoral Dissertations

A growing literature documents the inherently stressful nature of working with persons who are suffering or traumatized, and the potential for the development of stress disorders among social workers and other helpers. Previous studies of compassion fatigue and burnout have provided important information about professional and workplace variables that might influence risk, but little attention has been given to studying intrapersonal skills/abilities that might reduce risk and/or increase resilience and work satisfaction among helping professionals. This exploratory study asked whether levels of mindfulness, empathy, and emotional separation would influence professional quality of life, including compassion fatigue, burnout, and compassion satisfaction. …

The Relationship Of Anxiety, Coping, Thinking Style, Life Satisfaction, Social Support, And Selected Demographics Among Young Adult College Students, Jihan Saber Raja Mahmoud

University of Kentucky Doctoral Dissertations

Anxiety is prevalent among 13 % of young adult college students and is associated with emotional and behavioral consequences that adversely affect their mental and physical well-being. The major challenge for implementing evidence-based interventions is the lack of a multidimensional approach for evaluating anxiety in this population.

The purpose of this dissertation was to develop an evidence-based theoretical framework for studying the phenomenon of anxiety in young adult college students. Three studies were conducted to achieve this purpose. First, the psychometric properties of the 21-item shortened version of the Depression Anxiety and Stress Scale (DASS-21) were evaluated in a sample …

Trichloroethylene Exposure And Traumatic Brain Injury Interact And Produce Dual Injury Based Pathology And Pioglitazone Can Attenuate Deficits Following Traumatic Brain Injury, Andrew David Sauerbeck

University of Kentucky Doctoral Dissertations

The development of Parkinson's disease (PD) in humans has been linked to genetic and environmental factors for many years. However, finding common single insults which can produce pathology in humans has proved difficult. Exposure to trichloroethylene (TCE) or traumatic brain injury (TBI) has been shown to be linked to PD and it has also been proposed that multiple insults may be needed for disease development.

The present studies show that exposure to TCE prior to a TBI can result in pathology similar to early PD and that the interaction of both insults is required for impairment in behavioral function, and …

The Role Of The Nr4a Orphan Nuclear Receptor Nor1 In Vascular Cells And Atherosclerosis, Yue Zhao

University of Kentucky Doctoral Dissertations

The neuron-derived orphan receptor 1 (NOR1) belongs to the NR4A nuclear receptor subfamily. As an immediate early response gene, NOR1 is rapidly induced by a broad spectrum of physiological and pathological signals. Functional studies demonstrate NOR1 as a constitutively active ligand-independent nuclear receptor whose transcriptional activity is dependent on both expression level and posttranslational modifications. To date, an increasing number of studies have demonstrated a pivotal role of NOR1 in the transcriptional control of metabolism and the development of cardiovascular diseases.

In this dissertation, we demonstrate NOR1 expression in endothelial cells and sub-endothelial cells of human atherosclerotic lesions. In response …

Combinatorial Biosynthetic Derivatization Of The Antitumoral Agent Gilvocarcin V, Micah Douglas Shepherd

University of Kentucky Doctoral Dissertations

Gilvocarcin V (GV), the principal product of Streptomyces griseoflavus Gö 3592 and other Streptomyces spp., is the most prominent member of a distinct class of antitumor antibiotics that share a polyketide derived coumarin-based aromatic core. GV and other members of this class including polycarcin V from Streptomyces polyformus, often referred to as gilvocarcin-like aryl C-glycosides, are particularly interesting because of their potent bactericidal, virucidal and antitumor activities at low concentrations while maintaining low in vivo toxicity. Although the precise molecular mechanism of GV bioactivity is unknown, gilvocarcin V has been shown to undergo a photoactivated [2+2] cycloaddition of …

Strategies For Targeting Lentiviral Vectors, Christopher Matthew Trimby

University of Kentucky Doctoral Dissertations

Lentiviral gene therapy has held great promise for treating a wide range of neurological disorders due to its ability to stably integrate into the genome of nondividing cells like neurons, in addition to dividing cells. The nervous system is a complex and highly heterogeneous system, and while a therapeutic intervention may have beneficial effects in one population of cells it may have severe side effects in another. For this reason, specific targeting of lentiviral vectors is crucial for their ultimate utility for research and clinical research use.

Two different approaches for focusing the targeting of lentiviral vectors were employed in …

The Effect Of Joint Mobilization On Functional Outcomes Associated With Chronic Ankle Instability, Matthew C. Hoch

University of Kentucky Doctoral Dissertations

Ankle sprains are among the most common injuries sustained by physically active individuals. Although ankle sprains are often considered innocuous in nature, a large percentage of individuals experience repetitive sprains, residual symptoms, and recurrent ankle instability following a single acute sprain; otherwise known as chronic ankle instability (CAI). In addition to repetitive ankle trauma, those with CAI experience reductions in functional capacity over the life span. This indicates that current intervention strategies for CAI are inadequate and require further investigation.

The objective of this dissertation was to explore differences in walking and running gait parameters between individuals with and without …

Structures, Roles And Relationships Within Public Health’S Response To The 2009-2010 H1n1 Outbreak: The Ties That Bind Public Information Officers And Emergency Risk Communication Efforts, Kathleen G. Vidoloff

University of Kentucky Doctoral Dissertations

Little is known about the role of public health public information officers (PIOs) during public health emergencies. This study uses interpretative methods to learn about the organizational structures that facilitate and constrain emergency risk communication efforts during public health emergencies. Interpretive thematic comparative analysis of PIOs experiences and reflections about their involvement in the 2009-2010 H1N1 response will be used to illustrate how social interactions between and among PIOs, public health staff, and representatives from other agencies create implicit and explicit structures that facilitate and constrain emergency risk communication. The application of three specific concepts from structuration theory, namely, agent, …

Functional Connectivity For Configural And Featural Face Processing In The Broad Autism Phenotype, Jonathan Darrell Clark

University of Kentucky Doctoral Dissertations

During normal development, face processing involves a gradual shift from a featurally oriented style to a mature configural style by adolescence. This shift may coincide with increased right hemispheric dominance for faces supporting configural processing. Previous studies suggest that individuals diagnosed with ASD continue to process faces using individual parts and features into adulthood. This continued bias may be due to deficits in configural processing abilities. The current study investigated measures of functional connectivity during featural and configural processing of faces in broad autism phenotype sibling (ASD-sibs) children compared to age, sex, and handedness matched normal developing (ND) controls and …

Evaluation Of The Physicochemical Properties And Stability Of Solid Lipid Nanoparticles Designed For The Delivery Of Dexamethasone To Tumors, Melissa Howard

University of Kentucky Doctoral Dissertations

Pre-clinical and clinical trials suggest that pre-treatment with dexamethasone (Dex) may facilitate enhanced uptake of subsequently administered chemotherapeutic agents. To reduce the side effects associated with systemic administration of Dex, solid lipid nanoparticles (SLNs) containing dexamethasone palmitate (Dex-P) were prepared as a means of achieving tumor-targeted drug delivery. These studies were aimed at evaluating the physicochemical properties and both the physiological and storage stability of the SLNs.

SLNs were prepared using nanotemplate engineering technology. Stearyl alcohol (SA) was used as the lipid phase with Brij^® 78 and Polysorbate 60 as surfactants and PEG6000 monostearate as a long-chain PEGylating agent. …

Effect Of Azithromycin On Macrophage Phenotype During Pulmonary Infections And Cystic Fibrosis, Theodore James Cory

University of Kentucky Doctoral Dissertations

Azithromycin improves clinical outcomes in patients with cystic fibrosis (CF), specifically in patients infected with Pseudomonas aeruginosa. Azithromycin shifts macrophage programming away from a pro-inflammatory classical (M1) phenotype, and towards an anti-inflammatory alternative (M2) phenotype; however, little is known about this mechanism, nor of its impact upon immune response to pulmonary infection. We set out to determine the mechanism by which azithromycin is able to alter macrophage phenotype, and assess the effect of azithromycin induced macrophage polarization on inflammation during pulmonary infections.

Utilizing macrophage cell culture, we found that azithromycin increased IKKβ, a signaling molecule in the NFκB pathway, which …

Central Neural And Behavioral Correlates Of Voice Secondary To Induced Unilateral Vocal Fold Paralysis, Ashwini Joshi

University of Kentucky Doctoral Dissertations

Understanding the involvement of the central nervous system (CNS) in voice production is essential to incorporating principles of neuroplasticity into therapeutic practice for voice disorders. Early steps to attaining this goal require the identification of specific neural biomarkers of the changes occurring in the CNS from a voice disorder and its subsequent treatment. In the absence of an adequate animal vocalization model, the larynx has not been acutely and reversibly perturbed to concurrently examine the effect on both peripheral and central processing of the altered input/output.

Using a unique, reversible perturbation approach, it was the purpose of this study to …