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Electronic Theses and Dissertations

2017

Articles 1 - 13 of 13

Full-Text Articles in Physiology

Exogenous Ubiquitin: Role In Myocardial Inflammation And Remodeling Post- Ischemia/Reperfusion Injury, Stephanie Scofield Dec 2017

Exogenous Ubiquitin: Role In Myocardial Inflammation And Remodeling Post- Ischemia/Reperfusion Injury, Stephanie Scofield

Electronic Theses and Dissertations

Sympathetic stimulation occurs in the heart after injuries such as ischemia/reperfusion (I/R) and myocardial infarction and affects myocardial remodeling. Prolonged sympathetic stimulation can result in myocardial dysfunction through its effects on cardiac myocyte apoptosis and myocardial fibrosis. Ubiquitin (UB) is well known for its role of tagging old or damaged proteins for degradation via the UB-proteosome pathway. The role of exogenous UB however, is not fully understood. Previously, our lab showed that β-adrenergic receptor (β-AR) stimulation increased levels of extracellular UB in the conditioned media of adult rat ventricular myocytes and that UB inhibits β-AR-stimulated apoptosis. This study investigates the …

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Role Of Tlrs, Hippo-Yap1 Signaling, And Micrornas In Cardiac Repair And Regeneration Of Damaged Myocardium During Ischemic Injury, Xiaohui Wang Aug 2017

Role Of Tlrs, Hippo-Yap1 Signaling, And Micrornas In Cardiac Repair And Regeneration Of Damaged Myocardium During Ischemic Injury, Xiaohui Wang

Electronic Theses and Dissertations

Cardiovascular disease is a leading cause of death in the United States. Toll-like receptor (TLR)-mediated pathways have been demonstrated to play a role in myocardial ischemia/reperfusion (I/R) injury. We and others have shown that PI3K/Akt signaling is involved in regulating cellular survival and protecting the myocardium from I/R induced injury. In this dissertation, we provide compelling evidence that miR-125b serves to “fine tune” TLR mediated NF-kB responses by repressing TNF-a and TRAF6 expression. We constructed lentiviral expressing miR-125b, delivered it into the myocardium. The data showed that delivery of lentivirus expressing miR-125b significantly reduces myocardial infarct size and improves cardiac …

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Mitochondrial Transcription Factor A'S Role In Heart Failure., George H. Kunkel Aug 2017

Mitochondrial Transcription Factor A'S Role In Heart Failure., George H. Kunkel

Electronic Theses and Dissertations

Background: An essential mitochondrial component, Mitochondrial Transcription Factor A (TFAM) is reduced within the failing heart. TFAM maintains regulatory functions of cardiomyocyte physiology and stability. Mitochondrial Transcription Factor A forms a mitochondrial nucleoid anti-oxidant structure and reduces pathophysiological abnormalities to structural and contractile proteins. Overall, this functions to physically stabilize mtDNA. Significant molecular changes such as a loss of TFAM drive pathophysiological concentrations of cytoplasmic Ca2+ and reactive oxygen species. Both of these factors induce proteolytic enzymes to degrade the physiological cardiomyocyte. In TFAMs absence, heart function deteriorates and hypertrophic expansion ensues: thereby changing the physiological myocardium to a pathological …

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Divergent Responses Of Larval And Juvenile Blue Mussels To Low Salinity Exposure, Melissa A. May May 2017

Divergent Responses Of Larval And Juvenile Blue Mussels To Low Salinity Exposure, Melissa A. May

Electronic Theses and Dissertations

In this study, we compared the osmotic stress response of larval and juvenile blue mussels (Mytilus edulis) at the transcriptomic, metabolomic, and whole organism levels. Blue mussels inhabit coastal areas, where they face climate-induced reductions in nearshore salinity. Despite their ecological and economic importance, scientists do not fully understand the underlying transcriptomic and cellular mechanisms of the osmotic stress response in blue mussels or how the ability to respond to stress changes throughout development. Blue mussels spend the first weeks of life developing through several larval stages in the plankton. These early life history stages are more vulnerable …

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Enhancing Cell Therapy For Ischemic Cardiomyopathy., Michael J. Book May 2017

Enhancing Cell Therapy For Ischemic Cardiomyopathy., Michael J. Book

Electronic Theses and Dissertations

Cardiac cell therapy using cardiac mesenchymal cells (CMC) significantly reduces ventricular dysfunction in patients with ischemic cardiomyopathy. Despite the improvement in function, a modest number of CMCs survive in the heart post-transplantation. In this study, we sought to improve the survival and retention of transplanted CMCs to prolong the therapeutic benefits afforded by cardiac cell therapy. To do this, we targeted the enzyme telomerase (TERT), known to be active in some highly proliferating cells (e.g. germ, stem). TERT is responsible for preventing telomere attrition, thereby allowing continued proliferation. TERT has also been shown to be protective, improve cell migration and …

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Effects Of An Acute High-Volume Isokinetic Intervention On Circulating Levels Of Tnf-Α And Stnfr: Influence Of Age, Eliott Arroyo Delgado Jan 2017

Effects Of An Acute High-Volume Isokinetic Intervention On Circulating Levels Of Tnf-Α And Stnfr: Influence Of Age, Eliott Arroyo Delgado

Electronic Theses and Dissertations

The immune system has been implicated in recovery and muscle regeneration following exercise. In response to muscle damage, the immune system responds with an increase in circulating pro-inflammatory cytokines with the goal of recruiting leukocytes to the damaged area. Tumor Necrosis Factor-alpha (TNF-α), in particular, has been shown to be implicated in both muscle regeneration and muscle wasting. However, it remains unclear whether TNF-α is responsible for the age-related losses in muscle size and function. Also, due to the high clearance rate of TNF-α from circulation, analyzing the circulating levels of soluble TNF-α receptors 1 and 2 (STNFR1 and STNFR2) …

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Effects Of An Acute High-Volume Isokinetic Intervention On Inflammatory And Strength Changes: Influence Of Age, Joseph Gordon Jan 2017

Effects Of An Acute High-Volume Isokinetic Intervention On Inflammatory And Strength Changes: Influence Of Age, Joseph Gordon

Electronic Theses and Dissertations

PURPOSE: The purpose of this study was to compare the effects of a high volume isokinetic intervention on lower body strength and inflammation, as well as markers of muscle damage in the subsequent 48 hours between younger and middle-aged men. METHODS: 19 healthy, recreationally trained men were randomly assigned to two groups, younger adults (YA: 21.8 ± 2.0 y; 90.7 ± 11.6 kg; 21.5 ± 4.1 % body fat), or middle-aged adults (MA: 47.0 ± 4.4 y; 96.0 ± 21.5; 24.8 ± 6.3 % body fat). Both groups reported to the human performance laboratory (HPL) on four separate occasions. On …

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The Effects Of Sprint Interval Training And Maturity Status On Metabolic And Neuromuscular Fatigue Thresholds In Adolescents, Kyle Beyer Jan 2017

The Effects Of Sprint Interval Training And Maturity Status On Metabolic And Neuromuscular Fatigue Thresholds In Adolescents, Kyle Beyer

Electronic Theses and Dissertations

Purpose: To examine the maturity-related differences in the adaptations to systemic and localized fatigue thresholds (FTs) in response to sprint interval training (SIT) amongst adolescent male athletes. Methods: Twenty-seven adolescent male athletes, 11-17 years of age, completed pre-testing, six weeks of SIT, and post-testing. Participants were grouped according to their number of years from peak height velocity (PHV), an estimation of somatic maturity status, into PRE ( < -1.5yr), PERI (between -1.5 to +1.5yr) and POST ( > +1.5yr) PHV groups. Each testing session consisted of a ramp exercise protocol on a cycle ergometer. During the protocol, three systemic FTs, gas exchange threshold, ventilatory threshold, and respiratory compensation point were calculated …

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The Effect Of Repeated Sprint Training In Hypoxia And Beta-Alanine Supplementation On Exercise Performance, Ran Wang Jan 2017

The Effect Of Repeated Sprint Training In Hypoxia And Beta-Alanine Supplementation On Exercise Performance, Ran Wang

Electronic Theses and Dissertations

The primary objective of this study was to evaluate the synergistic effects of repeated sprint training in hypoxia (RSH) and beta-alanine supplementation on performance in recreationally active men. Participants were randomly assigned to one of the following groups: hypoxia + beta-alanine (HB, n = 10), hypoxia + placebo (HP, n = 9), normoxia + beta-alanine (NB, n = 11) and normoxia + placebo (NP, n = 8). All participants completed a total of 8 training sessions (each consisting of 3 sets of 5 × 10-s sprints at a resistance of 7.5% of body mass, with 20-s rest intervals between sprints) …

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Cardiovascular Risk, Remote Ischemic Postconditioning, And Endothelial Ischemia-Reperfusion Injury, Brian A. Hemenway Jan 2017

Cardiovascular Risk, Remote Ischemic Postconditioning, And Endothelial Ischemia-Reperfusion Injury, Brian A. Hemenway

Electronic Theses and Dissertations

Remote ischemic postconditioning (rIpost) is a potent vasculoprotective stimulus that is thought to reduce reperfusion injury associated with heart disease. However, certain animal models of cardiometabolic risk factors such as dyslipidemia, diabetes, and hypertension suggest the beneficial effects of rIpost to lessen reperfusion injury may be diminished. These findings have not been studied in clinically relevant humans. The aim of this study was to determine whether the protective effects of rIpost are reduced in the context of raised cardiometabolic risk in humans. Seven participants with raised cardiometabolic risk burden (age:57±7 years; BMI: 31±4kgm2participated in this 2X2 randomized cross-over …

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Effects Of Maternal Plane Of Nutrition On Early Embryo Development And Offspring Performance, Erin E. Beck Jan 2017

Effects Of Maternal Plane Of Nutrition On Early Embryo Development And Offspring Performance, Erin E. Beck

Electronic Theses and Dissertations

Nutritional changes immediately after insemination can result in increased embryonic mortality, but the mechanisms that cause this increased mortality and the impact on the embryos that survive are not known. Therefore, two experiments were conducted to evaluate the impact of a nutritional change immediately following AI on calf performance, global DNA methylation, estrus expression and interval to estrus in heifers, peripheral metabolites, uterine luminal fluid metabolites, and day 6 embryo quality. In the first study (chapter 2) Angus-cross heifers (n = 142) were allotted into two developmental treatments: drylot or range. All heifers were fixed-time inseminated to a single sire …

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The Effect Of Nitrate Supplementation On Exercise Tolerance And Performance: A Systematic Review And Meta-Analysis, Gavin Van De Walle Jan 2017

The Effect Of Nitrate Supplementation On Exercise Tolerance And Performance: A Systematic Review And Meta-Analysis, Gavin Van De Walle

Electronic Theses and Dissertations

The purpose of this paper was to systematically review the current literature and evaluate the overall efficacy of nitrate supplementation on exercise tolerance and performance by meta-analysis. Studies were eligible for inclusion if they met the following criteria: 1) were an experimental trial published in an English peer-reviewed journal; 2) compared the effects of inorganic nitrate consumption with a non-bioactive supplement control or placebo; 3) used a quantifiable measure of exercise performance; and 4) was carried out in apparently healthy participants without disease. A total of 29 studies were identified that investigated the effects of nitrate supplementation on exercise tolerance …

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The Effects Of Beetroot Juice On Vo2max And Blood Pressure During Submaximal Exercise, Jose M. Perez Jan 2017

The Effects Of Beetroot Juice On Vo2max And Blood Pressure During Submaximal Exercise, Jose M. Perez

Electronic Theses and Dissertations

Supplementation with beetroot juice (BR) has been shown to reduce blood pressure (BP) at rest and improve several performance parameters during submaximal and maximal exercise. BR effects on BP during submaximal exercise have not been investigated. Furthermore, the effects of BR on VO2max are inconclusive. The purpose of this study was to investigate the effects of BR on VO2max and BP during submaximal exercise. 20 healthy, recreationally trained volunteers (age 21.8±2.35 years, weight 75.10±10.62 kg, height 177.4±6.39 cm) participated in this study, which had a double-blind placebo controlled randomized crossover design. Participants began supplementation with either …

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