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Full-Text Articles in Life Sciences
Maternal Nicotine Exposure Induces Congenital Heart Defects In The Offspring Of Mice, Elizabeth Greco
Maternal Nicotine Exposure Induces Congenital Heart Defects In The Offspring Of Mice, Elizabeth Greco
Electronic Thesis and Dissertation Repository
Congenital heart defects are the most prevalent birth defect, and maternal cigarette smoking is a known risk factor. Nicotine replacement therapies are recommended to pregnant women who smoke to aid in smoking cessation, as this alternative is thought to be much safer compared to cigarette smoking. However, these products contain nicotine, and the safety of nicotine on the developing heart is not well known. In this thesis, a mouse model was used to test the hypothesis that maternal nicotine exposure (MNE) during pregnancy leads to congenital heart defects and coronary artery defects in the offspring of mice. MNE resulted in …
Reactive Oxygen Species And The Regulation Of Cerebral Vascular Myogenic Tone, Neil Mazumdar
Reactive Oxygen Species And The Regulation Of Cerebral Vascular Myogenic Tone, Neil Mazumdar
Electronic Thesis and Dissertation Repository
The myogenic response refers to the intrinsic ability of arteries to constrict to elevated pressure, developing “tone”. The underlying mechanism has yet to be elucidated but recent evidence suggests that the angiotensin II type 1 receptor (AT1R) is a key mechanosensor, linking intravascular pressure to tone development. One intriguing aspect of this receptor is its ability to activate NADPH oxidase (Nox), an enzyme responsible for the production of reactive oxygen species (ROS). The goal of this study was to ascertain the role of Nox in myogenic tone development. Isolated rat cerebral arteries were mounted in a myograph, pressurized to 60mmHg …
The Long Haul: Migratory Flight Preparation And Performance In Songbirds, Morag F. Dick
The Long Haul: Migratory Flight Preparation And Performance In Songbirds, Morag F. Dick
Electronic Thesis and Dissertation Repository
Migration requires birds to sustain high intensity endurance exercise for periods lasting from hours to days. Similar to athletes, preparation and nutrition is key to success. Birds seasonally prepare for migration, which includes increasing the capacity to oxidize fat in the flight muscles. Beyond fuelling migration, n-3 long-chain polyunsaturated fatty acids (PUFA) are hypothesized to be natural doping agents and increase endurance and fatty acid oxidative capacity. I examined how birds prepare for and sustain migratory flight and directly tested the role of n-3 PUFA. Using yellow-rumped warblers (Setophaga coronata) as a model species, I first examined the …
Ilk Modulates Stress-Induced Apoptosis In Epidermal Keratinocytes, Michelle Im
Ilk Modulates Stress-Induced Apoptosis In Epidermal Keratinocytes, Michelle Im
Electronic Thesis and Dissertation Repository
Integrin-linked kinase (ILK) is a ubiquitous scaffold protein that mediates cellular responses to integrin stimulation by extracellular matrix proteins. Mice with inactivation of the Ilk gene in squamous epithelia display defects in skin regeneration after injury, failure to thrive, and perinatal death. ILK-deficient epidermis exhibits reduced adhesion to the basement membrane and impaired hair follicle morphogenesis. In culture, ILK-deficient keratinocytes fail to attach and spread efficiently, and demonstrate decreased survival. We now show that ILK-deficient keratinocytes exhibit lower proliferative capacity and increased apoptosis in the absence or presence of growth factors. This reduced viability appears to be independent of the …
Mitochondrial Metabolic Suppression And Reactive Oxygen Species Production During Hypometabolism In Mammals, Jason Cl Brown
Mitochondrial Metabolic Suppression And Reactive Oxygen Species Production During Hypometabolism In Mammals, Jason Cl Brown
Electronic Thesis and Dissertation Repository
During hibernation, daily torpor, and fasting, mammals reduce metabolic rate (MR) up to 99%, 95%, and 30%, respectively, compared to resting levels. Mitochondrial metabolic suppression likely contributes to this MR reduction, and the first objective of this study was to determine the relative contributions of active, regulated inhibition and passive thermal effects as body temperature (Tb) falls, to mitochondrial metabolic suppression, and to examine the mechanisms involved using top-down elasticity analysis and novel statistical approach. The second objective of this study was to determine how mitochondrial metabolic suppression affects mitochondrial reactive oxygen species (ROS) production, a topic which …