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Full-Text Articles in Biomedical Engineering and Bioengineering
Friend Or Foe? The Role Of Transforming Growth Factor-Β (Tgfβ) Signaling In Calcineurin Inhibitor-Induced Renal Damage, Adaku Uwe
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With its incorporation into clinical practice in the early 1980s, the class of pharmacological agents known as calcineurin inhibitors (CNIs) quickly became the cornerstone of immunosuppressive therapy post-organ transplantation. However, its use is limited by irreversible kidney damage in the form of renal fibrosis. The molecular mechanism by which CNIs induce renal fibrosis remains to be better understood, and to date, there are no specific therapeutic strategies to mitigate this damage. This dilemma presents a critical need to explain mechanisms by which CNIs cause renal damage. Kidneys of patients on chronic CNI therapy show increased expression of the proinflammatory cytokine …
Vascular Endothelial Dysfunction And Effects On Arterial Wall Microstructure, Jeffrey Thomas Rodgers
Vascular Endothelial Dysfunction And Effects On Arterial Wall Microstructure, Jeffrey Thomas Rodgers
Theses and Dissertations
Vascular endothelial cell dysfunction (ECD) is a disease characterized by the inability of the vascular endothelial cells to transmit signaling molecules, namely nitric oxide (NO), in response to changes in blood flow rate. This disease is shown to be incident in the onset of more severe vascular disease such as hypertension, atherosclerosis, and heart failure. Long-term ECD is shown to cause long-term remodeling such as decreased flow-mediated dilation, increased pulse-wave velocity, intimal-medial thickening, and increased wall stiffness due to collagen deposition. We used second harmonic generation (SHG) microscopy to analyze this change in the collagen microstructure of the arterial extracellular …
Acute Oxygen-Sensing By The Carotid Bodies : The Thermal Microdomain Model, Ryan Joseph Rakoczy
Acute Oxygen-Sensing By The Carotid Bodies : The Thermal Microdomain Model, Ryan Joseph Rakoczy
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The carotid bodies (CB) are peripheral chemoreceptors that detect changes in arterial oxygenation and, via afferent inputs to the brainstem, correct the pattern of breathing to restore blood gas homeostasis. Elucidating the “signal” that couples carotid body sensory type I cell (CBSC) hypoxic mitochondrial inhibition with potassium channel closure has proven to be an arduous task; to date, a multitude of oxygen-sensing chemotransduction mechanisms have been described and altercated (Varas, Wyatt & Buckler, 2007; Gao et al, 2017; Rakoczy & Wyatt, 2018). Herein, we provide preliminary evidence supporting a novel oxygen-sensing hypothesis suggesting CBSC hypoxic chemotransductive signaling may in part …
Altered Skeletal Muscle Excitation-Contraction Coupling In The R6/2 Transgenic Mouse Model For Huntington's Disease, Daniel R. Miranda
Altered Skeletal Muscle Excitation-Contraction Coupling In The R6/2 Transgenic Mouse Model For Huntington's Disease, Daniel R. Miranda
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Huntington’s disease (HD) has classically been categorized as a neurodegenerative disorder. However, the expression of the disease-causing mutated huntingtin gene in skeletal muscle may contribute to the symptoms of HD, namely those that involve involuntary muscle contraction. In the R6/2 transgenic mouse model of HD, we previously observed ion channel defects that could contribute to involuntary muscle contraction. Here, in R6/2 muscle we investigated the consequence of these ion channel defects on action potentials (APs), the first step in excitation-contraction (EC) coupling. We found that the ion channel defects were associated with depolarizing the baseline membrane potential during AP trains. …
Als-Induced Excitability Changes In Individual Motorneurons And The Spinal Motorneuron Network In Sod1-G93a Mice At Symptom Onset, Christiana S.I. Draper
Als-Induced Excitability Changes In Individual Motorneurons And The Spinal Motorneuron Network In Sod1-G93a Mice At Symptom Onset, Christiana S.I. Draper
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Amyotrophic lateral sclerosis (ALS) is the most common motorneuron (MN) disease in adulthood. ALS is hallmarked by the progressive loss of MNs in the brain, brainstem, and spinal cord. Many hypotheses to explain the pathogenesis of ALS have been explored, but the exact mechanisms underlying the development of this disease remain unknown. However, abnormalities in MN excitability and glutamate excitotoxicity are the most widely studied. For decades, researchers have examined MN excitability in ALS, but the current literature is inconsistent, showing evidence of hyperexcitability, hypoexcitability, or no change in excitability of MNs in ALS. Many of these studies also focus …
Altered Skeletal Muscle Excitation-Contraction Coupling In The R6/2 Transgenic Mouse Model For Huntington's Disease, Daniel R. Miranda
Altered Skeletal Muscle Excitation-Contraction Coupling In The R6/2 Transgenic Mouse Model For Huntington's Disease, Daniel R. Miranda
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Huntington’s disease (HD) has classically been categorized as a neurodegenerative disorder. However, the expression of the disease-causing mutated huntingtin gene in skeletal muscle may contribute to the symptoms of HD, namely those that involve involuntary muscle contraction. In the R6/2 transgenic mouse model of HD, we previously observed ion channel defects that could contribute to involuntary muscle contraction. Here, in R6/2 muscle we investigated the consequence of these ion channel defects on action potentials (APs), the first step in excitation-contraction (EC) coupling. We found that the ion channel defects were associated with depolarizing the baseline membrane potential during AP trains. …
Biomarker-Performance Associations During Nutritional And Exercise Intervention In Air Force Personnel, Jennifer Jurcsisn
Biomarker-Performance Associations During Nutritional And Exercise Intervention In Air Force Personnel, Jennifer Jurcsisn
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This study evaluated the combined effects of an exercise intervention and nutritional supplement on biomarkers of stress and resilience, and the relationships of those markers with physical and cognitive performance. 130 healthy Active-Duty Air Force (AF) personnel were recruited to participate in a double-blind, placebo controlled 12-week exercise and nutritional intervention. Serum was collected at basal and high stress conditions pre- and post-intervention to track the following biomarkers: cortisol, dehydroepiandrosterone-sulfate (DHEA-S), norepinephrine (NE), neuropeptide Y (NPY), and serotonin. The exercise intervention significantly attenuated the cortisol response and peak stress cortisol levels. The nutritional intervention decreased peak stress NE. The selected …
Context-Dependence Of Physiological Systems: Environment-Physiology Interactions In The Respiratory Control System, Joseph M. Santin
Context-Dependence Of Physiological Systems: Environment-Physiology Interactions In The Respiratory Control System, Joseph M. Santin
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We know that animals are tuned to survive different environmental conditions or else life would not exist. Unfortunately, this is often forgotten or ignored when designing experiments. As Marsh Tenney articulated, "The physiologist keeps the whole always in mind. He accepts the tactical necessity of reductionism to understand parts, but, once done, for him it is only the beginning, never the end” (from Remmers, 2005). In an era when it is all too common to take environmental complexity out of the organism to understand physiology, my work puts some of that complexity back in the study of organisms. I take …
Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia
Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia
Master's Theses (2009 -)
Coarctation of the aorta (CoA) is a major congenital heart disease, characterized by a severe stenosis of the proximal descending thoracic aorta. Traditionally, surgery has been the treatment of choice for CoA. Dacron patch aortoplasty gained increased popularity after its introduction in the mid-twentieth century due to its advantages over other surgical treatment methods available at the time. A major complication with Dacron patch aortoplasty has been the formation of late aneurysm with as much as 51% incidence reported in follow up studies. The change in aortic morphology and formation of aneurysms after Dacron patch surgery could lead to local …