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The Impact Of Access To Oral Health Care On Inadequate Oral Health And Multimorbidity, Luis Limo

Electronic Thesis and Dissertation Repository

The connection between oral health and other non-communicable chronic conditions—commonly referred in the dental literature as the oral-systemic health connection—emphasizes the role of oral health care on both oral diseases and chronic conditions, particularly in vulnerable populations like the elderly. This thesis comprises 2 studies: the first is a systematic review on the impact of oral health care interventions, as an indicator of access to oral health care, on chronic conditions of which their co-existence would result in multimorbidity; the second study is a cross-sectional investigation of the associations between oral health, access to oral health care, and multimorbidity among …

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 …

Intersectional Social Inequalities And Cognitive Functioning Among Community-Dwelling Older Adults In England: A Decomposition Analysis Of The Mediating Role Of Loneliness, Chantel Walwyn

Electronic Thesis and Dissertation Repository

Normative cognitive decline is an emerging public health issue for older adult populations. It is necessary that we take an intersectional approach to examining heterogeneity in cognitive health outcomes. Using complex longitudinal survey data from the English Longitudinal Study of Ageing (ELSA), multiple linear regression models were used to examine the relationship between intersectional group membership based on age, education, and sex, and change in cognitive functioning domains (memory function, and executive function) over an 8-year period. Three-way decomposition analysis was also used to examine the mediating effect of loneliness on the association between intersectional group membership and the change …

The Effect Of Mtor Inhibitor Rapamycin On A Dietary Drosophila Melanogaster Model Of Calcium Oxalate Nephrolithiasis, Michael T. Pignanelli

Electronic Thesis and Dissertation Repository

Impaired cellular tolerance of reactive oxygen species (ROS) has been suggested as a common mechanistic link associated with aging in both metabolic syndrome and nephrolithiasis. The mechanistic (mammalian) target of rapamycin (mTOR) activity is characteristic of metabolic syndrome. When nutrients are abundant, mTOR is active. Conversely, fasting inhibits mTOR. Metabolic syndrome is correlated with an increased risk of self-reported or imaging findings of nephrolithiasis. At the individual level, patients with a higher BMI have an increased prevalence of recurrent symptomatic nephrolithiasis, 24-hour urinary excretion of oxalate, sodium, uric acid, calcium, and phosphorous as well as lower pH. Calcium oxalate crystals …

The Relationship Between Theory Of Mind And Executive Function: Are They Two Facets Of The Same Process Or Two Distinct Processes?, Isu Cho

Electronic Thesis and Dissertation Repository

This dissertation examines the relationship between Theory of Mind (ToM) and Executive Function (EF). There has been debate on whether ToM and EF are two facets of the same process or are two distinct processes. Distinguishing between these possibilities empirically is challenging because the two abilities have similar developmental timetables and ToM tasks typically place high demands on EF, with the consequence that ToM and EF performance measures may be artificially correlated. Three experiments explored the nature of this relationship. Experiments 1 and 2 tested whether socio-cultural factors known to influence individual differences in EF (i.e., bilingualism, country-of-origin) extend to …

The Effects Of Manual Tooth Brushing On Parotid And Submandibular/Sublingual Gland Salivary Flow Rates In Healthy Young And Older Adults, Kristen M. Trottier

Electronic Thesis and Dissertation Repository

Saliva is crucial for the maintenance of oral health. Individuals with reduced salivary flow may experience a distortion in taste, difficulty swallowing, and impaired articulation of speech. Research has shown that tooth brushing increases whole salivary flow rates in older adults. It is important to determine whether this increase results from the modulation of parotid gland salivary flow, submandibular and sublingual gland salivary flow, or both. Saliva produced from the parotid gland aids in digestive processes, while saliva secreted from the submandibular and sublingual glands promotes protection of the oral cavity. A within-subjects methodology was used to examine the effects …

The Effects Of A Multiple-Modality Mind-Motor Program On Vascular Outcomes In Community-Dwelling Older Adults With Subjective Cognitive Complaints, Amanda M. Deosaran

Electronic Thesis and Dissertation Repository

Studies have found a link between cardiovascular risk factors (CVRFs) and Alzheimer’s disease however; the mechanism by which CVRFs increase the risk of cognitive decline is not fully understood. The current study attempts to improve CVRFs in order to enhance cognition in older adults. Primary outcomes include ambulatory and clinical resting systolic and diastolic blood pressure (SBP; DBP). In total, 89 community-dwelling older adults with subjective cognitive complaints were randomized to either a multiple-modality mind-motor (M4) exercise or a multiple-modality (M2) exercise only. Significance was found in nighttime peak SBP (6.55 mmHg, p=.04) between groups, with a decrease in M2 …

Older Woman Workers: Met And Unmet Needs For Health And Wellbeing In The Workplace, Gillian Gorfine

Electronic Thesis and Dissertation Repository

Older women workers report experiencing occupational injustices however the literature focuses on barriers faced rather than understanding the needs-based strategies empowering women as they age at work. This study engaged women aged 55 and older in a participatory action research project defining and examining strategies for older women workers’ health and wellbeing. In Phase 1, a key informant advisory group (N = 4) defined the problem and guided the design of an open answer survey conducted with 72 older women in work. Three categories emerged informing the fundamental, instrumental, and contextual needs of older women workers. Meeting fundamental needs may …

Decreased Peak Muscle Power Is Associated With Motor Unit Loss In The Lower Limb Of Older Adults, Neal B. Mckinnon

Electronic Thesis and Dissertation Repository

This study investigated the relationship between motor unit (MU) properties and the strength and power of two lower limb muscles in healthy young and old adults. Twelve older adults (mean age, 77 ± 5 yrs) and twelve young adults (mean age, 24 ± 3 yrs) were studied. MU properties of the tibialis anterior (TA) and vastus medialis (VM) muscles were determined using decomposition-enhanced spike-triggered averaging (DE-STA). Motor unit number estimates (MUNE) of the TA were significantly reduced (p>0.05) in older adults (102 ± 76) compared to young adults (234 ± 109), primarily as a result of significantly larger surface-detected …

Aging And Obesity Models In Osteoarthritis, Sara Ohora

Electronic Thesis and Dissertation Repository

Osteoarthritis (OA) is a degenerative joint disease whose exact mechanisms are not well understood, but aging and obesity are common risk factors. To determine the role of transforming growth factor-alpha (TGFα) in obesity-associated OA, Tgfa null and control mice on control and high fat diets were compared. In addition, spontaneous OA was investigated in aging C57BL/6J mice. Quantitative magnetic resonance was used to assess body composition in the obesity model, while gait analysis, histological staining and OARSI scoring were used to determine OA in both models. Mice on high fat diet developed no OA, but Tgfa null mice weighed significantly …

Return To Work After Retirement: Contributing Factors And Health Implications, Jason Settels

Electronic Thesis and Dissertation Repository

An issue of mounting importance in many industrialized nations, including Canada, is that of population aging. Because of fears that this trend could result in labour force shortages, many national governments and international organizations have encouraged policies aimed at prolonging the working life. This thesis builds on work that has been done to identify factors relevant to the likelihood of involvement in post-retirement work by examining how interactions among various demographic variables impact this likelihood. Furthermore, we investigated how post-retirement work is related to three measures of health and well-being. As well as confirming results obtained by others, we have …

Neuromuscular Function Following Lengthening Contractions, Geoffrey A. Power

Electronic Thesis and Dissertation Repository

Unaccustomed lengthening contractions have been shown to impair muscle function - however little is known regarding this impairment on muscle power - specifically, the velocity component of power during voluntary contractions in humans. The four studies presented in my thesis investigated power-loss following lengthening contractions in healthy young and old women and young men.

The purpose of Study 1 was to determine reliability of velocity-dependent power of the dorsiflexors using the isotonic mode of the Biodex Dynamometer. I determined the isotonic mode is reliable and can be used to track changes in velocity and power following fatigue and lengthening contractions. …

Trpm2 In The Central Nervous System: Physiological Role And Critical Regulatory Pathways, Jillian C. Belrose

Electronic Thesis and Dissertation Repository

TRPM2 is a non-selective cation channel which is permeable to calcium. Although expression is highest in the brain, the physiological role for TRPM2 in neurons was unknown. Furthermore, our understanding of the pathways regulating TRPM2 channel function required further investigation. In this thesis, we identified that TRPM2 is required for NMDAR-dependent long-term depression (LTD). No change in NMDAR expression or function was observed following genetic deletion of TRPM2. Instead, the loss of NMDAR-LTD in TRPM2 knockout mice results from diminished GSK-3β activation. We next examined whether age in vitro could facilitate TRPM2 currents. We demonstrate that diminished glutathione with age …

Neuroprotective Effects Of Long-Term Endurance Training On The Cortical Autonomic Network In The Aging Brain, Torri A. Luchyshyn

Electronic Thesis and Dissertation Repository

This study tested whether long-term endurance training in older adults (ET; n = 15, 55 ± 4 years, relative VO₂max = 50 ± 8 ml/kg/min) would alter cardiovagal control and preserve the cortical autonomic network compared to age-matched controls (CON; n = 15, 56 ± 4 years, relative VO₂max = 37 ± 9 ml/kg/min). The hypothesis predicts 1) altered deactivation patterns of the ventral medial prefrontal cortex (vMPFC) in response to isometric hand grip (IHG) and 2) greater indices of cardiovagal control; a) increased baroreflex sensitivity at rest, b) greater heart rate change (ΔHR) and c) …

Reductions In Muscle Quantity And Quality In Old And Very Old Men: New Insights Into The Progression Of Sarcopenia, William J. Booth

Electronic Thesis and Dissertation Repository

Healthy adult aging is associated with sarcopenia; a loss of skeletal muscle mass known as. Major contributors to this process include functional and morphological changes in the contractile tissue and within the neuromuscular system. Currently, the relationship between muscle mass, normalized strength, structural integrity, and neuromuscular properties [such as motor unit number estimates (MUNE)], in the tibialis anterior (TA) with aging is largely unknown. Therefore, to examine this relationship we recruited twelve young (25 ± 3 years old), six old (68 ± 5 years old) and six very old (79 ± 3 years old) men. Magnetic resonance (MR) images were …

Physical Function During Performance-Based Tasks And Throughout Daily Life. Is It Different Across Levels Of Frailty?, Olga Theou

Electronic Thesis and Dissertation Repository

The overall aim of this thesis was to provide a more focused understanding about the physical function of older women across levels of frailty. The specific aims were: 1) Examine the physical function of older women across levels of frailty during performance-based tasks and throughout their normal daily life; and 2) Review the effectiveness of current exercise interventions for the management of frailty. To answer these aims an observational study of community-dwelling older women (63-100 years) from rural Greece and a comprehensive systematic review on the impact of exercise on frail older adults were conducted. The performance-based measures that had …