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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Effect of aging and diet on the expression of antioxidant enzymes in male Fischer F344 rats

Govinda Rao, Yelagalawadi S. Richardson, Arlan. January 1989 (has links)
Thesis (Ph. D.)--Illinois State University, 1989. / Title from title page screen, viewed October 24, 2005. Dissertation Committee: Arlan Richardson (chair), David Borst, Herman E. Brockman, H. Tak Cheung, Lynne A. Lucher. Includes bibliographical references (leaves 112-128) and abstract. Also available in print.

Age-related changes in the immune system and immunologic interventions

Pahlavani, Mohammad A. Cheung, Tak H. Richardson, Arlan. January 1987 (has links)
Thesis (Ph. D.)--Illinois State University, 1987. / Title from title page screen, viewed August 17, 2005. Dissertation Committee: Tak H. Cheung, Arlan Richardson (co-chairs), Harry Huizinga, Lynne Lucher, Mathew Nadakavukaren. Includes bibliographical references (leaves 90-102) and abstract. Also available in print.

The effect of menopausal status on substrate utilization in younger women during submaximal exercise

Pittinger, Elizabeth Smith 09 April 2016 (has links)
<p> PURPOSE: The purpose of this study was to determine if surgically-induced menopause in younger women affects substrate utilization during submaximal exercise while controlling for other potential confounds. METHODS: Thirteen untrained female subjects (33-50 years old) were recruited: oophorectomized (Group O = 5) and premenopausal controls (Group C = 8). Two separate visits included: body composition and maximal treadmill exercise test; followed by substrate utilization via open-circuit spirometry during 45 minutes of treadmill walking at 50% VO<sub>2max</sub>. RESULTS: When controlling for multiple variables affecting whole-body substrate utilization (age, VO<sub>2max</sub>, physical activity, body composition, fasting glucose, menstrual phase and diet), there was no difference in substrate utilization between pre- and postmenopausal women as measured by respiratory exchange ratio (RER) (0.83 &plusmn; 0.04 v 0.84 &plusmn; 0.03, <i>p</i>=0.47). CONCLUSIONS: Menopausal status does not appear to have an effect on substrate utilization during submaximal exercise in younger women.</p>

Subjective disability and mortality risk among elderly Mexican Americans with severe physical limitations

Cantu, Phillip 14 October 2014 (has links)
Using the disablement process as a framework, we examine the impact of the degree of concordance between objective measures of functional capacity, based on performance oriented mobility assessments (POMAs), and self-assessed disability, based on respondents’ reports of the ability to independently perform similar activities of daily living (ADLs), on mortality for elderly Mexican Americans over a seventeen year period. The analyses are based on the longitudinal Hispanic Established Populations for the Epidemiologic Study of the Elderly (HEPESE). We label respondents with serious POMA’s limitations who also report ADL disability “realists”, while we label those with POMA’s limitations who report no ADL disability “optimists”. Logistic models reveal that mortality rates are higher for “realists” than for “optimists”. The association between optimism and mortality is mediated by more complex measures of disability and reveals the complex cognitive and social construction of self-reported measures of physical functioning. We discuss the implications of the discrepancies for understanding predictors of functional decline in the older Mexican-origin population. / text

Implicit theories of aging : predictions of developmental change in parents versus generalized adults

Vernon, Anne Elizabeth 02 June 2017 (has links)
Two studies were conducted to investigate how normative conceptions of aging compare with adult children's expectations of change for their parents. In Study 1, the Implicit Theories of Aging Questionnaire (ITAQ) was developed to assess implicit theories of aging as pertaining to either one's mother, one's father, the average woman, or the average man. Respondents rated various aspects of everyday functioning as to (a) the direction and degree of expected change versus stability across the latter portion of the adult life course, (b) the estimated age of change onset, and (c) the target's ability to influence change. The second study replicated findings of the first, and extended it by exploring the relationship between implicit theories of aging and factual knowledge about the elderly as measured by Palmore's Facts on Aging Quiz. Results of the two studies indicated that people share highly similar beliefs about the direction, timing, and modifiability of aging-related change. For all four targets, respondents predicted more developmental change than stability and more losses than gains, but there was a strong optimistic bias in developmental predictions for parents. As compared to normative conceptions, parents were expected to undergo significantly fewer and significantly less severe declines in functioning. This optimistic bias did not appear to generalize to other belief components. Both parents and generalized adults were expected to undergo most functional loss during their mid-60s, and were thought to have some ability to influence loss. Judgments of modifiability seemed based in part on the perceived severity and timing of decline. Findings suggested that individuals may distinguish between aging-related loss that occurs through the intensification versus waning of existing attributes and abilities. It was hypothesized that increasing proportions of falsely held beliefs about old age would be correlated with predictions of greater aging-related decline. However, there was no association between misconceptions of aging and developmental beliefs, suggesting a possible distinction between implicit notions of the aging process and group-level generalizations about old age. These results, their generalizability, directions for future research, and practical implications were discussed. / Graduate

The prevalence of sarcopenia & pre-sarcopenia among general medical and surgical patients

Van Jacobs, Amanda C. 15 June 2017 (has links)
<p> Limited data is available to determine the ability of subjective nutrition assessment tools to reliably discover sarcopenia among patients admitted to general medical floors (GMF). Patients were included if subjective global assessment (SGA, nutrition status), abdominal computed tomography (CT, muscle mass in Skeletal Muscle Index (SMI)) scan, and handgrip strength (HGS, muscle function) were completed within 7 days of hospitalization. Sarcopenia was determined using European Working Group on Sarcopenia guidelines (SMI &lt;41 cm<sup>2</sup>/m<sup>2</sup> for women, SMI &lt;43 cm<sup>2</sup>/m<sup> 2</sup> for men with BMI &lt;25 kg/m<sup>2</sup> or &lt;53 cm2/m<sup> 2</sup> for men with BMI >25 kg/m<sup>2</sup> and handgrip strength measures &lt;30 kg for men and &lt;20 kg for women). A Pearson's Chi-Squared was utilized to determine associations between sarcopenia and nutrition status. A total of 141 subjects were included, 30% of which were sarcopenic, although only 55% of these patients were correctly classified by SGA. Future research is needed to develop an appropriate nutrition assessment tool to enhance SGA. </p>

The Relationships Among Sleep Quality, Frailty, and Falls in Older Adults Residing in the Community

Staal, Jacqueline 06 June 2017 (has links)
<p> One in three American older adults fall every year, making falls the leading cause of nonfatal injury treated in the emergency department (Centers for Disease Control and Prevention [CDC], 2013). Fall-related injuries cost the United States healthcare system nearly $30 billion a year and result in 27,000 deaths per year (Burns, Stevens, &amp; Lee, 2016). The risk of falls increases with age, occurring more often in women than man. Age-related muscle weakness and functional decline contribute to fall risk. Age-related changes in neuroendocrine hormone production and shifts in circadian rhythms promote sleep disorders, affecting nearly two-thirds of older adults. Poor sleep quality over time leads to drowsiness and impaired attention span and judgment. The purpose of this secondary analysis of a previously collected data set was to describe the relationships among frailty, subjective sleep quality, and falls in community-dwelling older adults. This secondary analysis also sought to determine the extent to which frailty and subjective sleep quality predict risk of future falls among community-dwelling older adults. Correlational analyses were performed to determine the nature and significance of the relationship between sleep quality and falls, frailty and falls, and sleep quality and frailty. A multiple regression analysis was performed to determine if sleep quality and frailty combined could predict falls. Frailty was found to account for a small variance in fall risk. However, sleep quality was not significantly related to falls nor was sleep quality predictive of falls. Risk for falls should be assessed at every clinical encounter and efforts to promote restful sleep should be addressed at least annually to reduce the risks of falls, functional decline, and sleep disorders among older adults in the community.</p>

Evaluation of Adjustment Criteria in Institutions for the Aged

Wolford, Lenore L. 08 1900 (has links)
This thesis focuses on the question of how the elderly adjust to changed living conditions. This question is vitally important, not only to the older person but also to their relatives.

The Aging Inmate Crisis: Institutional Adjustment and Post-Prison Outcome Differences between Older and Younger Prisoners

Unknown Date (has links)
In the past two decades, the older prisoner population in the U.S. has experienced unprecedented growth (Carson & Sabol, 2016; Scaggs & Bales, 2016). In fact, older prisoners represent the fastest growing inmate population (Carson & Sabol, 2016). This growth has become an important policy concern for government officials and correctional administrators because these prisoners are substantially more expensive to incarcerate and less likely to reoffend compared to younger prisoners (Chettiar et al., 2012). Older prisoners are more fiscally demanding to correctional systems due to healthcare and special housing considerations (Chettiar et al., 2012; Nowotny et al., 2015; Lemieux, Dyeson, & Castiglione, 2002; Linder & Meyers, 2007; Reimer, 2008). Older prisoners also represent a diverse population comprised of different criminal history profiles. While many prisoners are first time servers in old age, others are chronic offenders who have been in and out of prison multiple times (Beckett, Peternelj-Taylor, & Johnson, 2003). However, there is a void in prior literature regarding differences in the in-prison adaptation and post-prison reentry experiences among these inmates based on being a first time server and alternative definitions of what constitutes being an 'older prisoner. The current study seeks to fill two gaps in the prior literature on older prisoners. First, it will assess how older inmates differ from younger inmates in terms of in-prison adjustment and post-prison outcomes. Previous research studies find that older prisoners are less likely to engage in most types of prison misconduct (Blowers & Blevins, 2015) and to reoffend after prison release relative to their younger counterparts (Durose et al., 2014). What is less documented in prior studies is whether the employment prospects for older ex-convicts differ from those among younger prisoners and the extent to which finding work may, in turn, affect recidivism. Second, this study highlights the heterogeneity that exists among older versus younger inmates in their prison adaptation and reentry outcomes based on age and criminal history. A large percentage of older prisoners have never been previously incarcerated in prison. The Florida Department of Corrections 2013-2014 Annual Report shows that 46.2 percent of prisoners age 50 or older were committed to prison for the first time (Florida Department of Corrections, 2014). Prior research suggests that first time older prisoners may have an especially adverse response, and ultimately adjustment, to their commitment to prison which is manifested through institutional rule violations in the presence of family conflict, suicidal thoughts, depression, and fear of death (Aday, 1994; Leigey, 2015). This study uses data from a release cohort of former prisoners in Florida from 2004 to 2011 to examine differences between younger versus older prisoners. The data include institutional measures, pre-prison employment and criminal histories, and post-prison employment and recidivism information to examine differences in prison adjustment and post-release outcomes among different age groups and being a first time server among older versus younger inmates. By examining the effects of alternative age definitions on three primary outcomes—(1) prison misconduct, (2) post-prison employment, and (3) recidivism—this study contributes to prior literatures on gerontology, prison management, age stratification of post-prison employment opportunities, and recidivism. This study's focus on using old age as a key variable for explaining in-prison and reentry process outcomes is pertinent to a broader study of gerontology because it addresses important issues faced by a special subset of older adults within society. This study also contributes to the current literature on crime over the life course by assessing if and when older inmates are likely to find short-term employment and recidivate. / A Dissertation submitted to the College of Criminology and Criminal Justice in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Spring Semester 2017. / April 11, 2017. / Aging, Employment, Misconduct, Prisoners, Recidivism, Reentry / Includes bibliographical references. / William D. Bales, Professor Directing Dissertation; Melissa Radey, University Representative; Daniel Mears, Committee Member; Thomas G. Blomberg, Committee Member.

Appetite, food intake and ageing : the role of the gut

Parker, Barbara January 2005 (has links)
This thesis is concerned with gastrointestinal mechanisms and the changes that occur with age that may affect food intake and appetite. Studies are presented that evaluate the contribution of these mechanisms to the control of appetite in older persons. In particular, the use and validation of visual analogue scales in these studies and gastrointestinal aspects of appetite control, the effects of intraduodenal and gastric infusions of fat versus carbohydrate, relationships between gastric antral area and appetite ( using ultrasound measurements ) and the effect of accelerating gastric emptying ( with domperidone ) on appetite and food intake are addressed. Life expectancy is increasing both in Australia and overseas. Many health initiatives focus on decreasing food intake due to the increasing prevalence of obesity in our society, however reduced nutritional intake can also contribute to illness and death in older people. Ageing is associated with changes in gastrointestinal function affecting food intake. The spiralling costs of healthcare highlight the need for promotion and maintenance of healthy lifestyle choices, especially adequate nutritional intake, in older persons. Healthy ageing is associated with decreased appetite and food intake, the so-called ' anorexia of ageing '. This anorexia of ageing is a part of the normal process of ageing in people who do not suffer physical, psychiatric or social disorders. From young to old adult ( 18-70 years ) the average daily food intake falls by approximately 30 %. This reduction is probably in response to a normal decline in activity, however, when our food intake decreases more than our exercise levels weight loss, usually muscle, occurs. Unlike fat, loss of muscle has adverse effects including decreases in strength and increases in falls and fractures, loss of independence and increased risk of protein energy malnutrition, which in turn increases acute and chronic illness, hospitalisation and death. There are many explanations for changes in appetite and food intake in older people including sensory ( taste and smell changes, dental abnormalities ) and social ( poverty, loneliness, institutionalisation ) factors. Appetite regulation in humans is complex. Although many of the mechanisms are unclear, alterations in gastrointestinal responses to food ingestion are important in appetite ( how hungry or full we feel ) and food intake changes with age. Changes occur with increasing age in functions of the stomach and small intestine, including how quickly food and fluids leave the stomach and enter the small intestine to begin digestion, and changes in the way food is distributed and retained within the three sections of the stomach. These changes can influence appetite by increasing fullness and decreasing hunger. In addition, small intestinal hormones associated with appetite regulation increase with age and there is a greater sensitivity to their effects. The interaction of nutrients with gastrointestinal tract receptors stimulates the release of satiety hormones, including cholecystokinin ( CCK ), glucagon-like peptide-1 ( GLP-1 ), gastric inhibitory peptide ( GIP ) and amylin, and inhibits the release of ghrelin, which stimulates feeding. Visual analogue scales ( VAS ) are widely used in appetite research involving adults of all ages, yet the reproducibility and validity of these scales to evaluate appetite has not been assessed in older subjects. In two studies discussed in Chapter 4, retrospective ( to determine the relation of appetite sensations to food intake ) and prospective ( to determine reproducibility ), VAS were evaluated as a measurement of appetite in healthy older subjects. The retrospective study was a combined analysis of four single-blind, randomised, controlled appetite studies undertaken in young and older subjects and the prospective study was an assessment in healthy older men and women aged 65-85 years. Perceptions of appetite ( i.e. hunger and fullness ) were assessed by 100mm visual analogue scales administered at regular intervals. Food intake was quantified from food intake at a test meal. In the retrospective study, food intake at the test meal was positively related to perceptions of hunger, drowsiness, and calmness and inversely related to ratings of fullness taken immediately before the meal in both older and young subjects. In the prospective study, VAS measures of appetite were found to have comparable reproducibility and validity in older subjects to reported values in young adults. These observations confirm that food intake is related to perceptions of hunger and fullness as assessed by VAS in healthy older and young subjects, and suggest that sensations, not obviously associated with appetite, including ' drowsiness ' and ' calmness ', are also associated with food intake. Gastric distension reduces food intake, and antral rather than proximal, gastric distension may be the dominant mechanism in the initiation of appetite-related sensations. To evaluate the age-related changes in appetite, food intake, gastrointestinal hormone concentrations and antral area healthy young and older subjects were administered oral yoghurt preloads and water ( control ) 60 minutes prior to a buffet meal ( Chapter 5 ). Antral area was greater after the nutrient preloads than after water ( P = 0.001 ) and larger in the older than young subjects ( P = 0.005 ). Hunger ( r = -0.59, P < 0.001 ) and food intake ( r = - 0.90, P < 0.001 ) were inversely, and fullness directly ( r = 0.66, P < 0.001 ), related to antral area in both age groups. In healthy older and young subjects the suppression of subsequent food intake was nutrient-dependent and both satiation ( meal termination ) and satiety ( time to subsequent meal consumption ) were related to antral area, and antral distension. The effect of intragastric and intraduodenal administration of macronutrients, such as fat and carbohydrate, on appetite and food intake may be influenced by age. In Chapter 6, intragastric infusions of water ( 0 kcal ), carbohydrate and fat ( both 343 kcal ), were delivered over 5 minutes to older and young men. Food intake was assessed at a buffet meal. Carbohydrate infusion suppressed food intake significantly more than the fat infusion ( 23 v 10 %, P = 0.005 ), and this was so in both young ( 25 v 14 %, P = 0.03 ) and older ( 21 v 7 %, P = 0.05 ) men. These results were compared to equienergetic, equivolaemic fat and carbohydrate solutions delivered into the small intestine of older and young men. Fat inhibited food intake significantly more than carbohydrate in the young men ( 26 v 5 %, P < 0.001 ) whilst the suppressive effects of fat and carbohydrate were similar in the older men ( 21 v 22% , P = 0.05 ). This suggests that with increasing age regional differences in the gastrointestinal tract play both distinct and interacting roles in appetite regulation. Ghrelin is a recently identified peptide hormone secreted primarily from the gastric mucosa. It plays a role in energy balance by stimulating appetite, thereby increasing food intake and enhancing weight gain and fat mass deposition. Plasma ghrelin concentrations increase with fasting and are suppressed by nutrient intake. In Chapter 7, the contribution of both the stomach and small intestine in postprandial suppression of ghrelin was assessed. On three separate days, glucose ( 300 kcal ) and water ( C, 0 kcal ) were infused slowly over 150 minutes into the stomach ( IG ), and an equienergetic infusion of glucose was infused into the small intestine ( ID ) of older men and women. Ghrelin was suppressed following both glucose infusions compared to control ( ID 25 % and IG 19 % v C, P < .00001 ). There was no difference in the degree of suppression between the two glucose infusions ( P = 0.2 ). These results suggest that although the primary source of ghrelin is the gastric mucosa, small intestinal exposure is largely responsible for ghrelin suppression in humans. The effect of age on the suppression of ghrelin in response to nutrient intake is unclear. Domperidone, a prokinetic drug, is a predominantly peripheral acting dopamine2-receptor antagonist known to accelerate gastric emptying. It has been reported to be effective in the treatment of gastrointestinal symptoms associated with non-ulcer dyspepsia, Parkinson ' s disease and diabetic gastroparesis. The acute effects of domperidone on perceptions of appetite and food intake in healthy older people may include a reduction in antral distension ( as a result of more rapid gastric emptying and pharmacologically-induced gastric ' relaxation ' ) and meal-related symptoms, and increases food intake at a subsequent meal. In Chapter 8, 10 older men were treated with either domperidone or placebo and food intake, appetite and antral area assessed after a yoghurt preload. There were no differences in appetite scores of food intake between the study days. There was a decrease in antral area and an increase in blood glucose concentrations on the domperidone day, suggesting an increase in gastric emptying, although this difference was not significant. Further studies are required to evaluate the effects of this prokinetic agent on gastric emptying and food intake in older subjects. As the causes of the anorexia of ageing are still largely unknown, the aim of this research was to examine the effects of ageing on appetite, food intake and gastrointestinal function. This research will provide further insight into the ' physiological ' anorexia of ageing and management of the frail elderly, whether resident at home, in acute or long-term care. / Thesis (Ph.D.)--School of Medicine, 2005.

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