Open Access. Powered by Scholars. Published by Universities.®

Medicine and Health Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 9 of 9

Full-Text Articles in Medicine and Health Sciences

Understanding Water Diffusion In Experimental Spinal Cord Injury Remote From Injury Epicenter, Alice Motovylyak Oct 2018

Understanding Water Diffusion In Experimental Spinal Cord Injury Remote From Injury Epicenter, Alice Motovylyak

Dissertations (1934 -)

Diffusion tensor imaging (DTI) has demonstrated success as a biomarker of spinal cord injury (SCI) severity as shown from numerous preclinical studies. However, artifacts from stabilization hardware at the lesion have precluded its use for longitudinal assessments. Previous research has documented ex vivo diffusion changes in the spinal cord both caudal and rostral to the injury epicenter. The aim of this dissertation was to quantify the structural changes that lead to different diffusion measures in the rat cervical spinal cord after a thoracic contusion injury in an attempt to find a biomarker of injury. Animals received a thoracic contusion injury …


Understanding Relationships Between Early Life Toxic Stress, Childhood Socioeconomic Disadvantage, And Allostatic Load In Adolescence, Amanda King Jul 2018

Understanding Relationships Between Early Life Toxic Stress, Childhood Socioeconomic Disadvantage, And Allostatic Load In Adolescence, Amanda King

Dissertations (1934 -)

Chronic disease prevalence among children and adolescents is rising, which is thought to result in part from elevations in allostatic load (AL). AL is the cumulative physiological dysregulation that results from exposure to biological, social and environmental stressors over time. Socioeconomic disparities in chronic disease and AL have been well-documented in adult populations, including links between childhood socioeconomic disadvantage (CSD) and AL, yet little is known as to whether CSD may begin to impact AL earlier in life. Differential exposure and vulnerability to stress among racial/ethnic minorities may increase risk for elevated AL among those experiencing CSD. Framed by the …


Inference And Analysis Of Multilayered Mirna-Mediated Networks In Cancer, Duc Do Jul 2018

Inference And Analysis Of Multilayered Mirna-Mediated Networks In Cancer, Duc Do

Dissertations (1934 -)

MicroRNAs (miRNAs) are small noncoding transcripts that can regulate gene expression, thereby controlling diverse biological processes. Aberrant disruptions of miRNA expression and their interactions with other biological agents (e.g., coding and noncoding transcripts) have been associated with several types of cancer. The goal of this dissertation is to use multidimensional genomic data to model two different gene regulation mechanisms by miRNAs in cancer. This dissertation results from two research projects. The first project investigates a miRNA-mediated gene regulation mechanism called competing endogenous RNA (ceRNA) interactions, which suggests that some transcripts can indirectly regulate one another's activity through their interactions with …


Investigation Of Reactive Oxygen Species Production In The Rat Lung Using Optical Imaging, Nina Friedly Apr 2018

Investigation Of Reactive Oxygen Species Production In The Rat Lung Using Optical Imaging, Nina Friedly

Master's Theses (2009 -)

Oxidative stress, the imbalance between production of oxidants or reactive oxygen species (ROS) and antioxidant activity, plays a key role in the pathogenesis of acute and chronic lung diseases. The objective of this thesis was to develop a robust protocol for measuring the rate of H2O2 production in isolated perfused rat lungs and to determine the cellular sources of that rate using Amplex Red (AR). For a given lung, AR (25 mM) along with horseradish peroxidase (5 U/ml) and ascorbate oxidase (1U/ml) were added to a perfusate reservoir that was recirculated through the lungs and sampled at 5 minute intervals …


The Famous Names Discrimination Task As A Biomarker Of Alzheimer's Disease Risk: An Erp Study, Elizabeth Rose Paitel Apr 2018

The Famous Names Discrimination Task As A Biomarker Of Alzheimer's Disease Risk: An Erp Study, Elizabeth Rose Paitel

Master's Theses (2009 -)

Current ERP research emphasizes age- and pathology-related declines in neural processing in the form of attenuated amplitudes and prolonged latencies. Notably, there is a gap in the ERP literature regarding neural processing trajectories in the time between healthy young adulthood and clinical MCI/AD samples. fMRI research, however, has demonstrated periods of increased, compensatory activation in healthy, cognitively intact APOE ɛ4 carriers both during resting state and event-related tasks (Bondi, Houston, Eyler, & Brown, 2005; Evans et al., 2014; Filippini et al., 2009; Rao et al., 2015), consistent with compensatory theories of cognitive aging (Cabeza, 2002; Park & Reuter-Lorenz, 2009; Reuter-Lorenz …


Mechanisms Of Fatigue With Aging: Evidence From The Whole-Limb To The Single Cell In Humans, Christopher W. Sundberg Apr 2018

Mechanisms Of Fatigue With Aging: Evidence From The Whole-Limb To The Single Cell In Humans, Christopher W. Sundberg

Dissertations (1934 -)

Aging is accompanied by a loss of muscle mass and increased fatigability of limb muscles making it difficult for old adults to generate the force and power necessary to perform daily activities, such as ascending a flight of stairs. The mechanisms for the age-related increase in fatigability in old and very old adults (≥80 yrs) and whether there are differences between men and women are unknown. The purpose of this dissertation was to determine the mechanisms for the age-related increase in fatigability in men and women by studying fatigue at the level of the whole-limb and within the muscle cells. …


The Impact Of Advance Directives On The Intensity Of Care Received In The Acute Care Setting In Older Adults, Marsha Helen Tyacke Apr 2018

The Impact Of Advance Directives On The Intensity Of Care Received In The Acute Care Setting In Older Adults, Marsha Helen Tyacke

Dissertations (1934 -)

The proportion of older adults in the U.S. is rapidly increasing. One-third of Medicare expenditures occur in the final year of life, with nearly half resulting from acute exacerbations of chronic, progressive diseases(Riley & Lubitz, 2010). Older adults prefer comfort over life-sustaining care, and decreased intensity of care is associated with improved quality of life at the end-of-life (EOL). Advance directives (ADs) have been proposed as mechanisms to improve congruence between patient wishes and EOL care; however, the impact of ADs on care delivered in the acute care setting at the EOL for this population is unclear. A retrospective, correlation …


Chronic Stress And Reproductive Function In Female Childhood Cancer Survivors, Theresa Marie Hardy Apr 2018

Chronic Stress And Reproductive Function In Female Childhood Cancer Survivors, Theresa Marie Hardy

Dissertations (1934 -)

Reproductive dysfunction is reported as a major concern for childhood cancer survivors (CCS) and is highly correlated with quality of life in this population. Few predictors of post-treatment reproductive function in CCS have been identified. CCS report high levels of psychological stress. Psychological stress activates the hypothalamic-pituitary-adrenal axis, which can disrupt reproductive function. The purpose of this exploratory study was to explore the relationship between perceived stress, biomarkers of hypothalamic-pituitary-adrenal activity, gonadotropin levels, and anti-Müllerian hormone levels in female CCS. This exploratory cross-sectional study included female cancer survivors (ages 16-35) treated for pediatric cancer at the Royal Hospital for Sick …


Compressed Sensing For Few-View Multi-Pinhole Spect With Applications To Preclinical Imaging, Benjamin Michael Rizzo Apr 2018

Compressed Sensing For Few-View Multi-Pinhole Spect With Applications To Preclinical Imaging, Benjamin Michael Rizzo

Dissertations (1934 -)

Single Photon Emission Computed Tomography (SPECT) can be used to identify and quantify changes in molecular and cellular targets involved in disease. A radiopharmaceutical that targets a specific metabolic function is administered to a subject and planar projections are formed by imaging emissions at different view angles around the subject. The reconstruction task is to determine the distribution of radioactivity within the subject from the projections. We present a reconstruction approach that utilizes only a few view angles, resulting in a highly underdetermined system, which could be used for dynamic imaging applications designed to quantify physiologic processes altered with disease. …