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Physiological Resolution Of Periodic Breath Holding During Heavy Intensity Fartlek Exercise, David J. Lim
Physiological Resolution Of Periodic Breath Holding During Heavy Intensity Fartlek Exercise, David J. Lim
Electronic Thesis and Dissertation Repository
The purpose was to compare the physiological responses to periodic 5 s breath holds (CBH), increased power output (FLK), and both (FBH) every 30 s followed by 25 s of continuous heavy intensity cycling exercise with free-breathing (CON). Minute ventilation (V̇ E) was greater (p < 0.05) in CBH (97.58 + 16 L·min-1) and FBH (100.9 + 19 L·min-1), pulmonary oxygen uptake (V̇ O2p) was similar in CBH (2.73 + 0.14 L·min-1) and FBH (2.73 + 0.14 L·min-1) and greater in FLK (2.85 + 0.12 L·min-1), compared to CON (2.71 + 0.12 L·min-1). FBH also resulted in slower V̇ O2p kinetics (62.2 + 19 s) and greater blood lactate concentrations (11.5 + 2.7 mM), compared to CON (48.8 + 12 s; 9.0 + 2.3 mM). Together, we demonstrated that breath hold-induced hypoxemia and hypercapnia were resolved when not combined with additional work.
Niacin And Microvascular Endothelial Cell Response To Fatty Acid Excess And Hypoxia, Dominic Pang
Niacin And Microvascular Endothelial Cell Response To Fatty Acid Excess And Hypoxia, Dominic Pang
Electronic Thesis and Dissertation Repository
Niacin can reduce vascular disease risk, but its mechanism of action is controversial, and may not be dependent on systemic lipid modifying effects. This thesis tested the hypothesis that niacin directly improves endothelial cell function under lipotoxic and low oxygen conditions, as seen in ischemic conditions during metabolic syndrome, and investigated the potential mechanism involved. Human microvascular endothelial cell (HMVEC) survival was reduced by exposure to excess fatty acids under both normoxic and low oxygen conditions. Angiogenic function, as determined by tube formation on Matrigel, was impaired during fatty acid overload under either normoxic or low oxygen conditions. These effects …
Hypoxia-Induced Alterations In Skeletal Muscle Cell Respiration And Resveratrol As A Potential Pharmacological Intervention, Kathleen R. Belgrave
Hypoxia-Induced Alterations In Skeletal Muscle Cell Respiration And Resveratrol As A Potential Pharmacological Intervention, Kathleen R. Belgrave
Electronic Thesis and Dissertation Repository
Using the C2C12 mouse muscle myoblast cell line, I sought to investigate the hypothesis that differentiation under hypoxia impairs muscle mitochondrial respiratory function irreversibly. Resveratrol (RSV) will increase expression of markers of mitochondrial biogenesis and reverse the hypoxia-induced depression of O2 consumption rates. Hypoxia decreased oxygen consumption rates after five days of differentiation and after two days of normoxic recovery. This coincided with a hypoxia-induced decrease in protein levels of the NDUFB8 subunit of complex I of the electron transport chain and decreases in mRNA levels of mitochondrial biogenesis transcription factors, both of which could contribute …