Life Sciences Commons^™

Dexterous Manipulation Capabilities Are Associated With Change In Discharge Rate Properties Of Motor Neurons With Age, Mukta N. Joshi

Theses and Dissertations

Aging is accompanied by declines in manual dexterity and fine motor control. The purpose of this research was to compare hand motor control in young and older adults and examine the neuromuscular mechanisms responsible for enabling these interactions. We test force variability during isometric and dynamic contractions, manual dexterity and track motor unit activity to identify the neuromuscular mechanisms responsible for changes in dexterity with age. 26 older adults (66-86 years) and 28 young adults (19 – 38 years) participated in the study. Research participants performed force matching tasks during index finger abduction, precision pinch, static pressing and hybrid force/ …

Using A Toxic Aging Coin To Assess Hexavalent Chromium-Induced Neurotoxicity., Samuel Thomas Vielee

Electronic Theses and Dissertations

We are facing an aging crisis, with 20% of the U.S. population projected to be geriatric (65+) by 2030 and live another 40+ years. Age-related diseases accompany a growing geriatric population, emphasizing the need to understand their etiology. Environmental pollutants compound this crisis by: 1) geriatrics are more susceptible, exacerbating age-related diseases and comorbidities, and 2) they accelerate biological aging, inducing age-related diseases at younger ages. We address this crisis using a ‘toxic aging coin’ approach; heads examines how age impacts toxicity, tails examines how chemicals accelerate aging. This thesis applies the heads side for Cr(VI)-induced neurotoxicity across ages. We …

Effects Of Aging On Post-Exercise Oxygen Consumption: A Preliminary Study, Steven Klepacz

Health, Exercise, and Sports Sciences ETDs

Aging and excess post-exercise oxygen consumption (EPOC) is something that has not been adequately studied. Studies looking at EPOC mostly are compiled of young college age individuals. Aging in humans is a topic of much research with still more to be learned. The study in this paper attempts to answer the question of whether age affects EPOC when performing a certain exercise. Preliminary findings based on general age-related research suggest the possibility. This thesis will explore the current research related to age and EPOC, analyze the findings, and discuss additional avenues for future research.

Oligodendrocyte 2phatal Reveals Dynamics Of Myelin Degeneration And Repair, Timothy W. Chapman

Dartmouth College Ph.D Dissertations

Oligodendrocytes are responsible for producing myelin in the central nervous system. This lipid-rich coating along axons helps to increase action potential velocity, provide metabolic support to axons, and facilitate fine-tuning of neuronal circuitry. Demyelination and/or myelin dysfunction is widespread in neurodegenerative diseases and aging. Despite this, we know very little about how individual oligodendrocytes, or the myelin sheaths they produce, degenerate. Myelin repair, carried out by resident oligodendrocyte precursor cells (OPCs), is known to occur following myelin damage in certain contexts. We sought to investigate the cellular dynamics of oligodendrocyte degeneration and repair by developing a non-inflammatory demyelination model, combining …

Quantifying Balance: Computational And Learning Frameworks For The Characterization Of Balance In Bipedal Systems, Kubra Akbas

Dissertations

In clinical practice and general healthcare settings, the lack of reliable and objective balance and stability assessment metrics hinders the tracking of patient performance progression during rehabilitation; the assessment of bipedal balance plays a crucial role in understanding stability and falls in humans and other bipeds, while providing clinicians important information regarding rehabilitation outcomes. Bipedal balance has often been examined through kinematic or kinetic quantities, such as the Zero Moment Point and Center of Pressure; however, analyzing balance specifically through the body's Center of Mass (COM) state offers a holistic and easily comprehensible view of balance and stability.

Building upon …

Investigating The Roles Of The Dorsal And Ventral Striatum In Humor Comprehension And Appreciation Throughout Health, Aging, And Parkinson’S Disease, Maggie Prenger

Electronic Thesis and Dissertation Repository

Humor processing is thought to involve two distinct components. The first, humor comprehension, involves detecting and resolving incongruities that are present within a humorous stimulus. This is related to cognitive processes such as ambiguity resolution, response inhibition, working memory, and cognitive flexibility, functions that are mediated in part by the dorsal portion of the striatum (DS). Humor appreciation, on the other hand, refers to the subjective amusement and mirth that one experiences in response to a joke. This is related to reward processing, which implicates the ventral portion of the striatum (VS). Across three separate studies, we investigated the involvement …

Effects Of Parkinson’S Disease On Motor Asymmetry, Deborah Mazanek Watson

Theses and Dissertations

Introduction: Persons with Parkinson’s disease (PD) experience changes cortically, subcortically and behaviorally. This dissertation examines the asymmetry of motor behavior to explore the role of asymmetry in persons with PD and its connection to clinical symptoms. Purpose: Project 1: To assess the hand asymmetry difference in young adults versus older adults. Project 2: To investigate the difference in hand asymmetry in older adults and persons with PD. Project 3: To explore the correlation between function and clinical symptoms of persons with PD. Methods: 55 right-handed participants [Young Adults (YA) = 20, Female = 10; Older Adults (OA) = 20, Female …

Neuroinflammatory And Metabolomic Temporal Dynamics From Inhaled Wildfire Smoke With Attenuation Via Pharmacological Intervention, David Scieszka, David Scieszka

Biomedical Sciences ETDs

Wildfire smoke is a global issue affecting nearly all humans on the surface of this Earth. Smoke dispersion from wildfires can span continents and cross oceans with amazing ease. Furthermore, total acres of land burned per year in the United States has roughly doubled since 1980, meaning this issue will persist for an indeterminate amount of time. Exposure to wildfire smoke is hazardous and promotes aging-associated events in the cardiopulmonary systems. Yet long- and short-term effects on the brain remain relatively unknown. From these, it is critically important to understand the neurological impacts from wildfire smoke exposure; to compare these …

All The Rage: Assessing The Age/Rage Signaling Pathway’S Effects On Healthspan And The Physiological Processes Of Aging, Brandon Ashmore

Honors Theses

Advanced glycation end products (AGEs) are protein, lipid, or nucleotide molecules that have been combined with sugars through nonenzymatic, irreversible glycation and oxidation reactions. Their accumulation in the body has been associated with the natural aging process and a wide range of pathologies, including chronic inflammation, sustained oxidative stress, diabetes, neurodegenerative diseases, atherosclerosis, and cancer. Their interaction with the receptor for advanced glycation end products (RAGE) has been linked to several proinflammatory signaling pathways associated with neurotoxicity and vascular lesions. While some research has been done on the possible health benefits of RAGE inhibition to extend lifespan, our study hopes …

Impacts Of Dietary Restriction On A Drosophila Model Of Werner Syndrome, Eileen Sember

College of Arts & Sciences Senior Honors Theses

Werner syndrome (WS) is an autosomal recessive disorder that results in premature aging and occurs in 1 in 1,000,0000 to 1 in 10,000,000 people. In humans, WS is the result of mutations that render the WRN gene, that contains a helicase and an exonuclease domain, non-functional. Currently, there is no cure for WS in humans, making dietary and lifestyle interventions attractive for increasing the quality and longevity of lives. Diet restriction (DR) has been shown to extend the lifespan of several model organisms, including Drosophila melanogaster, making it a strong candidate for WS treatment. In this thesis, mutant flies …

Nicotinamide Riboside And Beta-Hydroxybutyrate Activate Parallel Pathways For C. Elegans Lifespan Extension, Mckenzie Peters

Undergraduate Honors Theses

Supplementation with nicotinamide riboside (NR), a form of vitamin B3 and a precursor of nicotinamide adenine dinucleotide (NAD⁺) extends lifespan in the nematode C. elegans and delays aging-related pathologies in mammals. During aging, levels of NAD⁺ decline causing metabolic dysfunction and oxidative damage. Studies in C. elegans found that when NR was administered during larval development it induced the mitochondrial unfolded protein response (UPR^mt), which is frequently associated with lifespan extension. Both calorie restriction (CR) and ketogenic diets (KD) have been shown to extend lifespan, in part through increasing NAD⁺ and through increasing levels …

Obstacle Crossing In Healthy Young And Older Individuals, Hope M. Hanson, Ashlyn M. Jendro, Abigail C. Schmitt

Health, Human Performance and Recreation Undergraduate Honors Theses

Introduction: In the United States, the average population age is rising and will continue to increase in the coming years.With an older population comes increased risk of injury associated with falls. Falls are considered a leading cause of injury and death in older individuals, and many falls are caused by body imbalance or obstacle collision due to a clearly visible stationary object (e.g., rug, chair, branch). Older adults tend to cross obstacles with increased toe clearance in order to prevent tripping, but much of what is known about obstacle crossing in older adults is limited to artificial obstacles that are …

The G Protein-Coupled Receptor (Gpcr) Fshr-1 And The Sphk-1 Lipid Kinase Regulate C. Elegans Life- And Healthspans Via A Common Pathway, Ryan Dennis Adkins

Undergraduate Honors Thesis Collection

Later years of life are often characterized by reduced cognitive function and mobility. One contributor is the cellular accumulation of reactive oxygen species (ROS), but our understanding of how cells respond to ROS to promote health and survival is incomplete. Follicle stimulating hormone receptor-1 (FSHR-1) and sphingosine kinase-1 (SPHK-1) mediate responses to oxidative stress and regulate life history traits in the roundworm Caenorhabditis elegans. The genes encoding both proteins are conserved in humans where they are implicated in stress responses, cell survival and neuronal function. fshr-1 and sphk-1 work together to mediate responses to intestinal oxidative stress in C. elegans. …

Assesment Of Structure, Function, And Microevolutionary Dynamics Of Extrachromosomal Circular Dna In Chinese Hamster Ovary Cells, Dylan Chitwood

All Dissertations

Chinese hamster ovary (CHO) cell lines are among the most popular expression hosts used in biopharmaceutical manufacturing due to relative ease of culture, capacity to perform human-like post-translational modifications, and non-susceptibility to viruses. However, the intrinsic plasticity of the CHO genome can lead to undesired genetic rearrangements, phenotypic shifts, reduced product quality, and early culture termination that prevents continuous biomanufacturing. A characteristic of plastic and unstable genomes that is poorly understood in CHO cells is extrachromosomal circular DNA (eccDNA). EccDNAs are focal amplifications of the genome that reside in the extranuclear space. These plasmid-like entities are structurally complex and are …

Age- And Sex-Dependent Alterations In Primary Somatosensory Neuronal Calcium Network Dynamics During Locomotion, Sami L. Case

Theses and Dissertations--Pharmacology and Nutritional Sciences

Over the past 30 years, the calcium (Ca2+) hypothesis of brain aging has provided clear evidence that hippocampal neuronal Ca2+ dysregulation is a key biomarker of aging. Indeed, age-dependent Ca2+-mediated changes in intrinsic excitability, synaptic plasticity, and activity have helped identify some of the mechanisms engaged in memory and cognitive decline. However, much of this work has been done at the single-cell level, mostly in slice preparations, and in restricted structures of the brain. Recently, our lab identified age- and Ca2+-related neuronal network dysregulation in the cortex of the anesthetized animal. Still, investigations in the awake animal are needed to …

A Long‐Term Obesogenic High‐Fat Diet In Mice Partially Dampens The Anti‐Frailty Benefts Of Late‐Life Intermittent Fasting, Yoko Henderson, Nazmin Bithi, Jie Yang, Christopher Link, Aili Zhang, Benjamin Baron, Eran Maina, Christopher Hine

Senior Honors Projects

The global obesity pandemic coupled with ever-growing life expectancies equates to hundreds of millions of individuals with potentially longer but not healthier lives. Aging is one of the risk factors for numerous maladies such as metabolic dis- order and frailty, which are exacerbated under obesity. Thus, therapeutic approaches that address obesity to ultimately improve afected individuals’ quality of life and extend their lifespan are needed. We previously reported that the every other day (EOD) fasting initiated late-life improved metabolic, musculoskeletal, and cognitive endpoints in standard rodent diet-fed mice. In the present study, using the same dietary intervention methodology, we tested …

The Effect Of Postural Perturbations On Cardiovascular And Skeletal Muscle Function In Healthy Adults, Patrick Siedlecki

Electronic Thesis and Dissertation Repository

Maintenance of standing balance is vital to daily living. Traditionally, perspectives on maintaining balance are achieved through the study of visual, vestibular and somatosensory inputs on motor outputs. While evidence suggests cardiovascular regulation also functions to assist postural control during orthostatic stress, how the cardiovascular system responds to postural perturbations is not well established. This dissertation includes four studies that investigated the effects of postural perturbations on the cardiovascular system and skeletal muscle responses in healthy adults. All of the studies involved exposing standing participants to surface-translation perturbations at different velocities, with known or unknown timing, and occurred while spontaneously …

Atrial Fibrillation In Aging: Mechanisms And Potential Therapeutics, Mengmeng Chang

USF Tampa Graduate Theses and Dissertations

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias seen in the clinics, and currently available antiarrhythmic pharmacotherapies in AF are not very effective. Although AF has been recognized as an aging-mediated disease, our understanding of the electrophysiological pathways that link aging and AF remain incomplete, which limits breakthroughs in the development of novel antiarrhythmic treatments for this disease. Studies have shown that aging increases the generation of reactive oxygen species (ROS) in the heart, and high levels of ROS have been associated with development of AF in animals and patients. Additionally, in some forms of AF, the …

Are Changes In Muscle Blood Flow Associated With The Age-Related Decrease In Critical Power?, Abigail Dorff

Theses and Dissertations

Aging results in lower exercise tolerance, manifested as decreased Critical Power (PCRIT). Aging is also associated with reduced physical activity, decreased muscle mass, and altered muscle blood flow, all of which may contribute to the age-related decrease in PCRIT. Purpose: The purpose of this study was to determine if the age-related decrease in PCRIT occurs independently of changes in physical activity and muscle mass and if it is related to impaired muscle blood flow. Methods: 10 Old (63.1 ± 2.5 years, 5 female and 5 male) and 10 Young (24.4 ± 4.0 years, 5 female and 5 male) physically active …

Effects Of Aging On Patellofemoral Joint Stress During Stair Negotiation On Challenging Surfaces, Nicholas Lynn Hunt

Boise State University Theses and Dissertations

Introduction: Patellofemoral pain is an incessant lower limb musculoskeletal disorder that may be underreported in older adults. During common locomotor activities, such as when negotiating stairs, older adults (over the age of 65 years) adopt knee biomechanics reported to increase patellofemoral pain. Negotiating stairs with a challenging surface, such as uneven or slick, may place greater demand on the knee and further exacerbate joint biomechanics related to PFJ stress. Yet, it is unknown if older adults exhibit increases in patellofemoral joint (PFJ) stress when negotiating stairs with challenging surfaces. Purpose: The purpose of this study was to examine the effect …

Regulation Of The Heat Shock Response Via Lysine Acetyltransferase Cbp-1 And In Neurodegenerative Disease In Caenorhabditis Elegans, Lindsey N. Barrett

USF Tampa Graduate Theses and Dissertations

The decline of proteostasis is a hallmark of aging that is, in part, affected by the dysregulation of the heat shock response (HSR), a highly conserved cellular response to proteotoxic stress in the cell. The heat shock transcription factor HSF-1 is well-studied as a key regulator of proteostasis, but mechanisms that could be used to modulate HSF-1 function to enhance proteostasis during aging are largely unknown. In this study, we examined lysine acetyltransferase regulation of the HSR and HSF-1 in C. elegans. We performed an RNA interference screen of lysine acetyltransferases and examined mRNA expression of the heat-shock inducible gene …

The Effects Of Aging On Wound Healing And Limb Regeneration In The Axolotl, Hande Sahin

Graduate Masters Theses

The Mexican axolotl is capable of regenerating various parts of its body and maintains this capacity throughout its entire life. Although this ability is sustained through adulthood, multiple regenerative processes appear to be negatively affected by aging. Here, we focus on evaluating the effect of aging on the rate of wound healing and limb regeneration. We have developed new in vivo, and ex vivo assays to characterize wound healing and identify differences between young and aged animals during this process. We have also characterized morphological features of mature skin from both groups of animals and although there are no obvious …

Innate Lymphoid Cell Characterization And Ilc2s In Neuroinflammation In Aging And Sex Differences, Alexis Mobley, Alexis S. Mobley

Dissertations & Theses (Open Access)

Aging affects immunologic responses by a global immune system suppression, including dysregulation of cytokine mediators, leading to increased inflammation throughout all systems, termed inflammaging. However, understanding healthy aging mechanisms can bypass this effect. Inflammaging also leads to poor outcomes during brain injury, making immune-targeting therapeutics tantamount to overall brain health and longevity. Moreover, sex affects disease etiology and severity through hormonal and chromosomal sex, as the X chromosome contains most immunology-based genes. Androgens have a generally suppressive effect on the immune system. Additionally, when immune responses are mounted, males are better at CD4+ T cell type (Th1) responses, while females …

Inflammaging: Inflammatory Biomarkers Associated With Nutrition, Metabolism And Muscle Tissue Oxygenation Relative To Sarcopenic Status In Older Adults, Marni Elise Shoemaker

Open Access Theses & Dissertations

The purpose of this study is to examine if we can differentiate inflammaging between sarcopenic and non-sarcopenic older adults by exploring if there are differences between biomarkers of inflammation and nutritional status in older adults with distinct differences in skeletal muscle mass, strength, and function, metabolic flexibility, and muscle tissue oxygenation. Twenty-one non-sarcopenic (mean±standard deviation, age = 73.1±6.2 yrs, n=5 males, n=5 females) and sarcopenic (age = 81.2±10.5 yrs, n=6 males, n=5 females) were categorized based on muscle mass and strength criteria according to the European Working Group on Sarcopenia in Older People. Body composition, handgrip and leg extension strength, …

Essential Amino Acid (Eaa) Regulation Of Skeletal Muscle Protein Turnover With Age, Mary Komp

Graduate Theses and Dissertations

Skeletal muscle (SM) is vital for both long term health and quality of life. Recent research suggests an increase in catabolic signals with age triggers pathologic conditions, such as sarcopenia. Although results from in vitro studies model how EAA can regulate muscle protein synthesis (MPS), the relevance of these models to muscle protein breakdown (MPB) and the presence of physiological EAA concentrations remains to be established. Therefore, the objective of this study was to determine the effects of a low, normal, and supra physiological dose of EAA (0.2, 1.0, and 3.0 x EAA) in a young (passages 2-10) and aging …

Ocean Quahog (Arctica Islandica) Population Dynamics: Sex-Based Demographics And Regional Comparisons In The Northwest Atlantic, Kathleen M. Hemeon

Dissertations

Arctica islandica (ocean quahog) is the longest-lived bivalve on Earth. Individuals on the deep continental shelf of the Mid-Atlantic (US) can survive for centuries, and when found in the colder, boreal waters of Iceland, ages over 500 years can be reached. The ocean quahog is important in the US, yet very little is known about the resiliency of the ocean quahog stock to fishing activity, and ocean quahog recruitment patterns over time. To quantify and constrain age-reader error prior to age analysis, a triple-method error protocol was developed for A. islandica that included age-reader bias, precision, and error frequency. The …

Age-Related Changes In Corticospinal Drive During Locomotor Adaptation, Sumire D. Sato

Doctoral Dissertations

During activities of daily living, locomotor patterns must be continuously adapted according to changes in our body (e.g., bodily injuries, fatigue) and to the changing environment (e.g., walking surface). Plasticity of spinal networks and supraspinal centers, including the cerebellum and cerebral cortex, have been shown to play important roles in human locomotor adaptation. However, the neural control of locomotion and the ability to adapt locomotor patterns are altered in older adults, which may limit activities of daily living and increase fall-related injuries in the elderly population. My dissertation project is focused on understanding the role of corticospinal drive during split-belt …

The Effect Of Anti-Aging Treatment On Expression Of Aging Markers In A Mouse Model Of Huntington Disease, Mary Isabelle E. Guerra

Honors Undergraduate Theses

Huntington disease (HD) is a fatal neurodegenerative disease caused by CAG tract expansion in the huntingtin (HTT) gene, which results in production of mutant huntingtin (mtHTT) protein. Although mtHTT is expressed throughout life, onset of HD symptoms typically begins in mid-life, around 35 to 50 years of age. Characteristic HD symptoms include motor, cognitive, and psychiatric abnormalities. The emergence of symptoms in adulthood suggests that aging may play a role in HD pathogenesis. Furthermore, markers of accelerated aging can be observed in HD patients, including telomere attrition, epigenetic alterations, and mitochondrial dysfunction. Our lab has previously observed that …

An Investigation Into The Mechanism Of Proteasome Dysfunction In Neurodegenerative Disease And The Biological Impact Of Proteasome Hyperactivation In C. Elegans, Raymond T. Anderson

Graduate Theses, Dissertations, and Problem Reports

Aging is an inevitable process that occurs as humans grow older. It is characterized by the chronological accumulation of cellular damage over time leading to functional decline as an organism grows older. Several processes are thought to contribute to the aging phenomenon, but one of the most prolific of these is the disruption of protein homeostasis (proteostasis). The collapse of proteostasis can lead to accelerated aging and the development of age-related diseases including devastating neurodegenerative diseases (NDs) like Alzheimer and Parkinson disease. Virtually all NDs are characterized by the buildup of proteins in and around neurons resulting in neuronal death …

“The Vehicle Was A Hockey Game”: A Holistic Approach To Aging For Older Men, Ryan Tomaselli

Electronic Theses and Dissertations

The many benefits of physical activity are well established. Nonetheless, there remains a need for qualitative research on aging and sports focused on the normalization of sport for older adults, and the increased opportunity for sport participation in older age. Aging and sport research, which has primarily focussed on older elite athletes, has found older adults value health-related benefits, social interaction, and resistance of the aging process through sport participation. However, research examining a broader scope of specific sport participation, such as hockey, in older age may provide a distinguished understanding of participation tied to meaning and lifestyle factors. Therefore, …