Historically, heavy metal research on sea turtles has been focused on deceased specimens, limitin... more Historically, heavy metal research on sea turtles has been focused on deceased specimens, limiting the ability to determine if the concentrations of heavy metals affected the health of the individuals. More recently, the collection and analysis of blood samples from live turtles has enabled the researcher to investigate the potential health implications of observed metal concentrations. In this thesis, I present two original studies on the blood concentrations of essential and non-essential heavy metals and their potential physiological correlates on the endangered loggerhead sea turtle (Caretta caretta). This work reflects analysis of archived samples collected in 2008 off the southeastern coast of the United States by the South Carolina Department of Natural Resources (SCDNR). Research was funded in part by the Office of Protected Resources and NOAA Fisheries. Samples were obtained through the generous support of Rusty D. Day, MSc. The first study examined the relationships between body size, sex, geographic location, water depth, and blood concentration of 17 essential and non-essential heavy metals and metalloids. Statistical analysis of these parameters indicated that measures of body size were correlated with several of the metals, whereas sex had no significant relationship with any of the metals examined. Several metal concentrations also varied with geographic location and depth of water in which the turtles were captured. The second study examined the potential health effects of these pollutants in C. caretta. Regression analyses were used to compare physiological (blood) parameters to metal concentrations. The significant associations between several physiological parameters and several nonessential toxic metals suggest that heavy metal pollution may influence the physiology and, potentially, the health of sea turtles. However, this study is limited in that it can only identify associations and cannot discern causal relationships. Therefore, further research is needed to clarify the effects heavy metal pollution may have on sea turtle health. A better understanding of the effects of heavy metal pollution on health in this endangered species will facilitate more effective monitoring and protection in the future, enabling us to more effectively conserve these fascinating creatures.
American journal of physiology. Lung cellular and molecular physiology, 2014
Premature infants requiring supplemental oxygen are at increased risk for developing bronchopulmo... more Premature infants requiring supplemental oxygen are at increased risk for developing bronchopulmonary dysplasia (BPD). Rodent models involving neonatal exposure to excessive oxygen concentrations (hyperoxia) have helped to identify mechanisms of BPD-associated pathology. Genome-wide assessments of the effects of hyperoxia in neonatal mouse lungs could identify novel BPD-related genes and pathways. Newborn C57BL/6 mice were exposed to 100% oxygen for 10 days, and whole lung tissue RNA was used for high-throughput, sequencing-based transcriptomic analysis (RNA-Seq). Significance Analysis of Microarrays and Ingenuity Pathway Analysis were used to identify genes and pathways affected. Expression patterns for selected genes were validated by qPCR. Mechanistic relationships between genes were further tested in cultured mouse lung epithelial cells. We identified 300 genes significantly and substantially affected following acute neonatal hyperoxia. Canonical pathways dysregulated in hyperox...
This is a pre-print copy of a paper that is currently under review. Please respect the intellectu... more This is a pre-print copy of a paper that is currently under review. Please respect the intellectual property of the author and the efforts of the publishers and reviewers until its publication. If you find any errors that need modification please contact the author at ...
Historically, heavy metal research on sea turtles has been focused on deceased specimens, limitin... more Historically, heavy metal research on sea turtles has been focused on deceased specimens, limiting the ability to determine if the concentrations of heavy metals affected the health of the individuals. More recently, the collection and analysis of blood samples from live turtles has enabled the researcher to investigate the potential health implications of observed metal concentrations. In this thesis, I present two original studies on the blood concentrations of essential and non-essential heavy metals and their potential physiological correlates on the endangered loggerhead sea turtle (Caretta caretta). This work reflects analysis of archived samples collected in 2008 off the southeastern coast of the United States by the South Carolina Department of Natural Resources (SCDNR). Research was funded in part by the Office of Protected Resources and NOAA Fisheries. Samples were obtained through the generous support of Rusty D. Day, MSc. The first study examined the relationships between body size, sex, geographic location, water depth, and blood concentration of 17 essential and non-essential heavy metals and metalloids. Statistical analysis of these parameters indicated that measures of body size were correlated with several of the metals, whereas sex had no significant relationship with any of the metals examined. Several metal concentrations also varied with geographic location and depth of water in which the turtles were captured. The second study examined the potential health effects of these pollutants in C. caretta. Regression analyses were used to compare physiological (blood) parameters to metal concentrations. The significant associations between several physiological parameters and several nonessential toxic metals suggest that heavy metal pollution may influence the physiology and, potentially, the health of sea turtles. However, this study is limited in that it can only identify associations and cannot discern causal relationships. Therefore, further research is needed to clarify the effects heavy metal pollution may have on sea turtle health. A better understanding of the effects of heavy metal pollution on health in this endangered species will facilitate more effective monitoring and protection in the future, enabling us to more effectively conserve these fascinating creatures.
American journal of physiology. Lung cellular and molecular physiology, 2014
Premature infants requiring supplemental oxygen are at increased risk for developing bronchopulmo... more Premature infants requiring supplemental oxygen are at increased risk for developing bronchopulmonary dysplasia (BPD). Rodent models involving neonatal exposure to excessive oxygen concentrations (hyperoxia) have helped to identify mechanisms of BPD-associated pathology. Genome-wide assessments of the effects of hyperoxia in neonatal mouse lungs could identify novel BPD-related genes and pathways. Newborn C57BL/6 mice were exposed to 100% oxygen for 10 days, and whole lung tissue RNA was used for high-throughput, sequencing-based transcriptomic analysis (RNA-Seq). Significance Analysis of Microarrays and Ingenuity Pathway Analysis were used to identify genes and pathways affected. Expression patterns for selected genes were validated by qPCR. Mechanistic relationships between genes were further tested in cultured mouse lung epithelial cells. We identified 300 genes significantly and substantially affected following acute neonatal hyperoxia. Canonical pathways dysregulated in hyperox...
This is a pre-print copy of a paper that is currently under review. Please respect the intellectu... more This is a pre-print copy of a paper that is currently under review. Please respect the intellectual property of the author and the efforts of the publishers and reviewers until its publication. If you find any errors that need modification please contact the author at ...
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