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The Role Of Trib3 In Insulin Resistance: Its Action As Nutrient Sensor And Regulator Of Insulin Action, Jiarong Lamiquiz

All ETDs from UAB

THE ROLE OF TRIB3 IN INSULIN RESISTANCE: ITS ACTION AS NUTRIENT SENSOR AND REGULATOR OF INSULIN ACTION JIARONG LIU LAMIQUIZ PATHOLOGY ABSTRACT Insulin resistance is a hallmark of Type 2 diabetes (T2DM). A reduced capacity for insulin to stimulate increases in glucose uptake and glucose oxidation in insulin sensitive tissues, such as skeletal muscle and adipose tissue, are common defects in patients with insulin resistance, T2DM, and other related diseases. Tribbles homolog 3 (TRIB3) has been demonstrated to play a role in insulin resistance by serving as a negative regulator of Akt in mouse liver, fat, and pancreas. In a …

Erythropoiesis In The Absence Of Adult Hemoglobin, Shanrun Liu

All ETDs from UAB

The mammalian erythrocyte is a highly specialized blood cell that differentiates via an orderly series of committed progenitors in the bone marrow in a process termed erythropoiesis. During erythroid development, hemoglobin synthesis increases from early erythroid progenitors to mature enucleated red blood cells (RBCs). Although hemoglobin is the most extensively studied protein in history, the role, if any, that hemoglobin plays in erythroid development remains obscure. In this study, I ask the question what happens during erythropoiesis in the absence of hemoglobin. I demonstrate that my original hypothesis that excess free heme would accumulate in the absence of globin chain …

Hemoglobin Switching, Thalassemia And Sickle Cell Disease In Humanized Knockin Mice, Sean Mcconnell

All ETDs from UAB

In this dissertation we describe knockin mouse models for the study of human hemoglobin disorders. These knockin human globin genes, in contrast to transgenes, replace the adult mouse globin genes, remain under control of endogenous mouse globin enhancer sequences and are inherited in a manner identical to globin alleles in man. Starting with various knockin alleles composed of unique human alpha, beta and gamma globin gene sequences, we evaluate several allele combinations towards our goal of generating improved models of thalassemia and sickle cells disease. We show that humanized knockin mice complete a fetal to adult hemoglobin switch during postnatal …

Piggybac Transposon Mutagenesis In Human And Mouse Stem Cells, Tingting Zhang

All ETDs from UAB

The most common genetic diseases worldwide, £] thalassemia and Sickle Cell Anemia (SCA) result from mutations in the adult £] globin gene. One promising therapeutic method to ameliorate these diseases is to reactivate the endogenous fetal f× globin gene. I hypothesize that an erythroid mutagenic transposon system can be used to activate f× globin gene expression. To test this hypothesis three lines of genetically modified mice were generated and bred together. The first is a transgenic mouse line that contains a multicopy array of erythroid mutagenic PiggyBac (PB) transposons. The second transgenic mouse line expresses the PB transposase (TPase) from …

Bone Morphogenetic Protein Signaling Pathways During Mouse Heart Development: Roles For Chd7 And Mycn, Cristina Harmelink

All ETDs from UAB

Bone Morphogenetic Protein (BMP) signaling pathways are imperative for proper heart development. BMP ligands bind serine threonine kinase receptors, which activate intracellular receptor-regulated SMAD proteins. SMAD1, SMAD5, and SMAD8 transduce BMP signals from the cytoplasm to the nucleus, where they regulate transcription. We have investigated two aspects of BMP signaling during mouse cardiogenesis: identifying SMAD1-interacting proteins and exploring the roles of a known BMP target, Mycn, in the developing myocardium. Chromodomain helicase DNA binding protein 7 (CHD7) is a highly conserved transcription factor that promotes protein synthesis, proliferation, and differentiation. Haploinsufficiency for CHD7 causes CHARGE syndrome, a developmental disorder characterized …

The Role Of Mitochondrial Oxidative Stress In Cardiovascular Disease Development, Corey Michael Harrison

All ETDs from UAB

An estimated 70 million Americans have one or more types of cardiovascular disease (CVD). Although the sequence of events leading to CVD are still controversial, there is a general consensus that atherosclerotic lesions result from oxidative stress associated with risk factor. For this study, it was hypothesized that endogenous mitochondrial oxidative stress would influence susceptibility to atherogenesis and mitochondrial damage mediated by CVD risk factor exposure. To test this hypothesis, atherosclerotic lesion formation, oxidant stress, and mitochondrial DNA damage were assessed in hypercholestoremic mice (apolipoprotein E null - apoE -/- SOD2 +/+) and mice with significantly decreased levels of the …

The Role Of Ll-37 In Prostate Cancer And Its Potential As A Therapeutic Target, Jonathan Adam Hensel

All ETDs from UAB

LL-37 is the only cathelicidin-derived anti-microbial peptide in humans and has been shown to stimulate proliferation, angiogenesis, cellular migration and inhibit apoptosis, in addition to serving as a chemoattractant for leukocytes. It is produced primarily by epithelial cells and leukocytes, and has recently been discovered to be over-expressed in breast, ovarian and lung cancers. Based on these findings, we compared levels of LL-37 expression in benign and cancerous human prostate tissues. Results of this investigation demonstrated that LL-37 is increasingly over-expressed in primary prostate tumors in a grade dependent manner and in metastatic lesions. Since the physiological mechanisms of LL-37 …

Altered Leptin Signaling On Dendritic Cells As A Potential Mechanism For Cancer Immunotherapy, Lorena Y. De Los Santos

Open Access Theses & Dissertations

Leptin is a pleiotropic hormone synthesized primarily by white adipocytes and its receptors are expressed in a variety of tissues and cells such as in the hypothalamus and cells of the immune system. Multiple cell types can produce a considerable amount of leptin such as skeletal muscle, placenta, and osteoblasts to name a few and its synthesis has been shown to be regulated by sex hormones and a broad range of inflammatory mediators. Although leptin has been shown to directly affect immune response, we are interested in how leptin affects dendritic cell function and their ability to induce a proper …

Development Of A Novel Metallo-Lipid Microparticle Delivery System For A Leishmania Mexicana Dna Vaccine Candidate, Joanna B. Valencia

Open Access Theses & Dissertations

ABSTRACT

Background and Significance.

The leishmaniases are an important group of neglected tropical parasitic diseases caused by parasitic protozoa of the genus Leishmania. International health authorities estimate that 350 million people around the world are at risk for contracting leishmaniasis. Two million new cases occur each year and 12 million people are presently infected worldwide. Leishmaniasis is endemic throughout the Americas region including all of Central America, most of South America, Mexico and southern Texas. Leishmania is also considered a threat to the military readiness of U.S. troops deployed to the Middle East or Latin America.

First- and second-line treatments …

Protein Kinase C Δ Is Critical For Nucleotide Excision Repair Of Cyclobutane Pyrimidine Dimers, Christopher Michael Negro

Master's Theses

Nucleotide excision repair (NER) is the process by which cells identify and repair bulky, helix-distorting DNA lesions such as ultraviolet (UV) radiation-induced cyclobutane pyrimidine dimers (CPD) and 6-4 photoproducts (6-4PP). NER in human cells is a complex biochemical process requiring several complementation groups. Defects in complementation group genes result in rare, autosomal recessive cancer syndromes such as xeroderma pigmentosum (XP), cockayne syndrome (CS), and trichothiodystrophy, supporting the tumor suppressive effects of NER. Protein Kinase C delta (PKCδ) expression is lost in squamous cell carcinomas where it functions as a tumor suppressor gene. Additionally, in response to UV radiation, PKCδ is …

Regional Expression Of Hoxa4 Along The Aorta And Its Potential Role In Human Abdominal Aortic Aneurysms, John H. Lillvis, Robert Erdman, Charles M. Schworer, Alicia Golden, Kimberly Derr, Zoran Gatalica, Laura A. Cox, Jianbin Shen, Richard S. Vander Heide, Guy M. Lenk, Leigh Hlavaty, Li Li, James R. Elmore, David P. Franklin, John L. Gray, Robert P. Garvin, David J. Carey, Wayne D. Lancaster, Gerard Tromp, Helena Kuivaniemi

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

The infrarenal abdominal aorta exhibits increased disease susceptibility relative to other aortic regions. Allograft studies exchanging thoracic and abdominal segments showed that regional susceptibility is maintained regardless of location, suggesting substantial roles for embryological origin, tissue composition and site-specific gene expression.

Results

We analyzed gene expression with microarrays in baboon aortas, and found that members of the HOX gene family exhibited spatial expression differences. HOXA4 was chosen for further study, since it had decreased expression in the abdominal compared to the thoracic aorta. Western blot analysis from 24 human aortas demonstrated significantly higher HOXA4 protein levels in thoracic …

Secreted Factors From Human Umbilical Cord Blood Cells Protect Oligodendrocytes From Ischemic Insult, Derrick Rowe

USF Tampa Graduate Theses and Dissertations

Oligodendrocytes (OL)s are the dominant cell type in the white matter and are integral for synaptic transmission essential for proper neuronal communication between brain areas. Previous studies have shown that intravenous administration of the mononuclear fraction of human umbilical cord blood (HUCB) cells in rat models of stroke reduced white matter injury, gray matter injury and behavioral deficits. Yet the mechanisms used by HUCB cells remain unknown in ischemic injury. These studies will investigate both in vitro and in vivo approaches to elucidate this mechanism in OLs. When mature primary OLs were coincubated with HUCB cells, HUCB cells secreted soluble …

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 …

Role Of Pi3k-Akt Pathway In The Age Associated Decline In Tlr Mediated Activation Of Innate And Adaptive Immune Responses, Mosoka Papa Fallah

University of Kentucky Doctoral Dissertations

Immunosenescence results in reduced immune response to infections with Streptococcus pneumoniae as well as to pneumococcal polysaccharide vaccines. The antibody response to the capsular polysaccharide (CPS) provides protection against S. pneumoniae infection. CPS immunoresponse is T cell independent and needs the macrophage-derived cytokines such as IL-12, IL-6 and IL-1β to elicit an antibody response. We showed a cytokine dysregulation, i.e. a decrease in IL-12, IL-6 and TNF-α but an increase in IL-10, in the aged (18-24 months old comparable to >65 years in human) compared to young adult mouse (8-12 weeks less than 65 years old) splenic macrophages (SM) or …

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 …

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 …

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 …

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 …

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 …

Internet Use And Its Impact On Secondary School Students In Chiang Mai, Thailand, Kesaraporn Wanajak

Theses: Doctorates and Masters

Internet addiction (IA) is a relatively new field of academic inquiry. Empirical studies suggest that IA, like other well researched addictive behaviours, has an effect on many aspects of a person‟s life, including academic/work performance, relationships, and physical and mental health (Goldberg, 1996; Young, 1996, 1998). Evidence of IA has been suggested by the findings that some Internet users spend increasingly longer periods of time online and experience withdrawal symptoms when offline. Those preoccupied with Internet-related activities may neglect exercise, family and social activities (Kim et al., 2010; Nalwa & Anand, 2003; Seo, Kang, & Yom, 2009; S. Yang & …

Yeast As A Model For Studying Aβ Aggregation, Toxicity And Clearance, Prashant R. Bharadwaj

Theses: Doctorates and Masters

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder of the central nervous system, characterised by acute memory loss and behavioural symptoms. The AD brain is characterized by the presence of senile amyloid plaques associated with degenerating neurites and inflammatory processes. The major protein component of these amyloid deposits is the amyloid beta (Aβ) protein. The Aβ protein is a 40 or 42 amino acid cleavage product of APP (Amyloid Precursor Protein) which is produced in low levels in the normal ageing brain. Although senile amyloid plaques is the major pathological hallmark of AD brains, accumulating evidence has been presented to …

The Role Of Hiv-1 Proteins In Alzheimer's Disease Pathology, Brian Nelson Giunta

USF Tampa Graduate Theses and Dissertations

Prevalence of HIV-associated cognitive impairment is rising, the worst form of which is HIV-associated dementia (HAD). The disease is fuiled by a chronic innate type pro-inflammatory response in the brain which is highly dependent upon the activation of microglia. We first created an in vitro model of HAD composed of cultured microglial cells synergistically activated by the addition of IFN-gamma and the HIV-1 coat glycoprotein, gp120. This activation, as measured by TNF-alpha and NO release, is synergistically attenuated through the alpha7nAChR and p44/42 MAPK system by pretreatment with nicotine, and the cholinesterase inhibitor, galantamine. As these medications have been FDA …

Mir-17* Suppresses Tumorigenicity Of Prostate Cancer By Inhibiting Mitochondrial Antioxidant Enzymes, Yong Xu, Fang Fang, Jiayou Zhang, Sajni Josson, William H. St. Clair, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

Aberrant micro RNA (miRNA) expression has been implicated in the pathogenesis of cancer. Recent studies have shown that the miR-17-92 cluster is overexpressed in many types of cancer. The oncogenic function of mature miRNAs encoded by the miR-17-92 cluster has been identified from the 5' arm of six precursors. However, the function of the miRNAs produced from the 3' arm of these precursors remains unknown. The present study demonstrates that miR-17* is able to suppress critical primary mitochondrial antioxidant enzymes, such as manganese superoxide dismutase (MnSOD), glutathione peroxidase-2 (GPX2) and thioredoxin reductase-2 (TrxR2). Transfection of miR-17* into prostate cancer PC-3 …

The Effects Of Age And Heterochromatin On Frequencies Of Acquired Chromosomal Aneuploidy In Uncultured Human Leukocytes, Noran Aboalela

Theses and Dissertations

While age-related sex chromosomal aneuploidy is a well-characterized phenomenon, the relationship between autosomal loss and age remains unclear. The emergence of the specific and highly sensitive fluorescence in situ hybridization (FISH) technology has enabled investigators to study interphase cells, thereby overcoming problems inherent with the study of metaphase spreads for acquired aneuploidy assessment. Despite all the advantages of this technique, there are some limitations that could be misleading when scoring interphase autosomal aneuploidy. In this study we show that sex chromosomal hypoploidy is correlated with age. By using a twin study design, we evaluated Y chromosome hypoploidy frequencies and found …

Campylobacter Ureolyticus: An Emerging Gastrointestinal Pathogen?, Susan Bullman, Daniel Corcoran, James O'Leary, Brigid Lucey, Deirdre Byrne, Roy D. Sleator

Department of Biological Sciences Publications

A total of 7194 faecal samples collected over a 1-year period from patients presenting with diarrhoea were screened for Campylobacter spp. using EntericBios, a multiplex-PCR system. Of 349 Campylobacter-positive samples, 23.8% were shown to be Campylobacter ureolyticus, using a combination of 16S rRNA gene analysis and highly specific primers targeting the HSP60 gene of this organism. This is, to the best of our knowledge, the first report of C. ureolyticus in the faeces of patients presenting with gastroenteritis and may suggest a role for this organism as an emerging enteric pathogen.

An Assessment Of The Use Of Chimpanzees In Hepatitis C Research Past, Present And Future: 1. Validity Of The Chimpanzee Model, Jarrod Bailey

Experimentation Collection

The USA is the only significant user of chimpanzees in biomedical research in the world, since many countries have banned or limited the practice due to substantial ethical, economic and scientific concerns. Advocates of chimpanzee use cite hepatitis C research as a major reason for its necessity and continuation, in spite of supporting evidence that is scant and often anecdotal. This paper examines the scientific and ethical issues surrounding chimpanzee hepatitis C research, and concludes that claims of the necessity of chimpanzees in historical and future hepatitis C research are exaggerated and unjustifiable, respectively. The chimpanzee model has several major …

Long-Term Hypoxia Regulates Cortisol Biosynthesis In The Ovine Fetal Adrenal Cortex, Vladimir Enrique Vargas

Loma Linda University Electronic Theses, Dissertations & Projects

Previous studies demonstrated enhanced fetal adrenal cortisol biosynthesis following exposure to long-term hypoxia (LTH). The studies presented here were designed to determine the mechanism(s) regulating this important adaptive endocrine response. Ewes were maintained at high altitude (3,820 m) from approximately day 40 to 138-141 of gestation. Fetal adrenal glands were then collected from LTH and age matched normoxic controls. Dispersed fetal adrenal cortical cells (FACs) were untreated, treated with ACTH, treated in combination with ACTH precursors (POMC and 22-kDa pro-ACTH), or pre-treated with H-89 and or UO126 followed by ACTH treatment. Following ACTH treatment, cortisol biosynthesis increased in both groups …

Analysis Of Β8 Integrin In Neurogenesis And Neurovascular Homeostasis, Aaron K. Mobley

Dissertations and Theses (Open Access)

Neurogenesis in the adult mouse brain occurs within the subventricular zone (SVZ) of the lateral ventricle. In the SVZ, neural stem cells (NSC) reside in a specialized microenvironment, or vascular niche, consisting of blood vessels and their basement membranes. Most NSCs in the SVZ differentiate into progenitor cells, which further differentiate to generate neuroblasts, which then migrate from the SVZ to the olfactory bulbs (OB) along the rostral migratory stream (RMS). ECM-mediated adhesion and signaling within the vascular niche likely contribute to proper NSC self-renewal, survival, differentiation and neuroblast motility. The mechanisms that control these events are poorly understood. Previous …

Interactions Of Francisella Tularensis With Components Of The Host Fibrinolytic System, Shawn Russell Clinton

Theses and Dissertations (ETD)

Francisella tularensis (FT) is a Gram-negative coccobacillus and causative agent of a life-threatening disease commonly referred to as tularemia. Due to the highly infectious nature of the organism, its previous development as a biowarfare agent and its potential use in acts of bioterrorism, this bacterium is listed as a Category A select agent by the Centers for Disease Control and Prevention (CDC). Efforts to understand the pathogenic mechanisms of FT within the host environment are vital for the development of safe and effective vaccines, as well as treatments, against tularemia. Though considered an intracellular pathogen, FT research of late has …

D2r Dopamine Receptor Mediates Changes In Dual Specificity Phosphatase Expression In A Small Cell Lung Cancer Cell Line, Scott Lemar Lattimer

Theses and Dissertations (ETD)

Bromocriptine, a D2 dopamine receptor (D2R) agonist, is used clinically as a treatment for pituitary tumors of a lactotroph origin. Many questions remain unanswered about the mechanism of this effect. The antiproliferative effect has not been demonstrated in DMS 53 cell line, a Small Cell Lung Cancer (SCLC). In this thesis, we have shown that treatment with NPA (N‑propylnorapomorphine), a dopamine receptor agonist inhibits ERK phosphorylation and proliferation in DMS 53 cells. NPA treatment causes significant increases in DUSP‑1 (MKP‑1), DUSP‑4 (MKP‑2) and DUSP5 mRNA. NPA treatment also correlates with increases in DUSP5 (hVHR3) protein visualized using Western Blot. These …