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The relationship between stress, physical activity and cognitive decline with ageVendittelli, Rebecca 29 August 2017 (has links)
Cognitive decline is often associated with increasing age. However, there is growing support that modifiable lifestyle factors such as exercise and stress influence outcomes. That is, physical activity (PA) seems to be protective, while stress engenders decline. Moreover, there is evidence to suggest that these variables interact such that being active positively moderates the negative effects of stress on cognitive decline. The present study examines the effects of both average PA and stress on cognitive decline (i.e., between-person effects), the coupled association between PA and cognition and stress and cognition (i.e., within-person, or occasion specific effects), and the possible interaction between PA and stress on cognitive outcomes. Coordinated analyses of The Memory and Aging Project (MAP; N = 1,853, mean age = 79) and Longitudinal Aging Study Amsterdam (LASA; N = 4,109, mean age = 68) were conducted. A series of multilevel models (MLM) were fit to the data, evaluating differences in baseline and linear change in perceptual speed, episodic memory, and MMSE scores in both data sets. Average PA was associated with the intercept of perceptual speed and episodic memory, and decline in all 3 outcomes in MAP only. There was a significant coupled association between PA and all cognitive outcomes in MAP, and with perceptual speed in LASA. Average stress was not associated with baseline scores or rates of change in any of the cognitive outcomes in either study. However, occasion specific stress was associated with perceptual speed and episodic memory in the unexpected direction in LASA. Lastly, there was a significant positive interaction between occasion specific stress and occasion specific activity on MMSE and perceptual speed scores in LASA. That is, on occasions when participants reported more stress than usual, if they also reported more exercise than usual, they tended to score better on these outcomes. Findings support the beneficial effects of both average and occasion specific activity on cognitive abilities, however failed to demonstrate the adverse effects of stress, and only partially supported an interaction between activity and stress. Limitations and future directions are discussed. / Graduate / 2018-07-10
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Cognitive control operations involved in switching tasks, and deficits associated with aging and Parkinson's diseaseWoodward, Todd Stephen 20 November 2017 (has links)
The purpose of this investigation was to identify the cognitive control operations involved in task switching, and to apply this understanding to a theoretical account of the qualitatively different task-switching deficits associated with aging versus Parkinson's disease (PD). Participants in young (N = 33), elderly (N = 34) and PD ( N = 34) samples switched between color naming and word reading in response to incongruent, neutral, or congruent Stroop stimuli and vocal response time (RT) was recorded. The results suggested that executive processes involved in switching selective attention between object attributes determined a substantial portion of task-switching RT costs. More specifically, these component control processes were identified as: (a) shifting selective attention from the stimulus dimension just attended to on the previous response to the now-relevant stimulus dimension (SHIFT), and (b) a preventative operation characterized by the partial inhibition of selective attention to the now-relevant stimulus dimension, carried out when the probability is high that the now-relevant dimension must be ignored on a future response (MODERATE). A multilayer, linear, parallel distributed processing (PDP) model was presented to demonstrate how these cognitive processes may be implemented by the cognitive system, and how these findings relate to the executive function concepts of the Supervisory Attentional System (SAS) and Contention Scheduling (CS). In addition, a cost associated with responding to the first member of a stimulus pair or triplet was also identified (FIRST); however, this operation appeared to function independently from the executive control operations involved in switching tasks (i.e., FIRST was also present for task repetition trials). Finally, a number of two-way interactions between these three main effects (SHIFT, MODERATE and FIRST) accounted for unique variance in task-switching RTs, such that RT was increased when these effects co-occurred. In the neuropsychological investigation it was demonstrated that the SHIFT and MODERATE effects were significantly greater for an elderly sample compared to a young sample, resulting in an increase in task-switching RT. This deficit was attributed to an inefficient shifts of selective attention. Conversely, PD did not necessarily affect the SHIFT and MODERATE operations, when compared to age-matched controls; however, the disease was associated with difficulty overcoming Stroop interference while switching tasks. This deficit was interpreted as affecting the SHIFT operation under the most taxing conditions, attributable to a central resource deficit in PD. In contrast, no between-group differences on the effect FIRST were observed. / Graduate
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Age differences in functional performance : deficits or artifacts?Dickerson, Anne E. 22 April 1991 (has links)
An experiment was conducted to compare the functional performance of 20 young adults and 20 older adults in two types of tasks. One type of task was normal activities of daily living which are meaningful, familiar, and well practiced while the other type was a contrived, relatively unfamiliar task of wrapping a package. While young and old adults did not differ in the ratings of the familiarity of the two tasks, results from an Age by Task Type mixed MANOVA demonstrated a significant age difference in both activities. This suggests that older adults show age-related decline with tasks even when those tasks are familiar, practiced, and ecologically valid.
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The Aging Lung and Cancer: Evidence of Field Cancerization from Transcriptional Profiles of Normal Human and Mouse Lung TissuesVilleneuve, Patrick James January 2010 (has links)
The effect of increased age on gene expression has not previously been evaluated in lung tissues. Cancer incidence increases with age, and lung cancer in particular has been found to have an incidence that peaks in the later decades of life. Based on previously published studies of aging effects in human muscle, kidney and retinal tissues, significant transcriptional changes are anticipated in both mouse and human aged lung tissues that may predispose to the development of cancer.
We examined lung aging between young and old mice (6 vs. 30 months), using a hybrid mouse model (CB6F1) and an experimental colorectal metastasis model (CT26 cells). We also recruited young (<30 years) and aged (>60 years) human patients. Microarray analysis of mouse lung tissues using MOE430v2 and human lung tissues suing HG U133 2.0+ Affymetrix arrays was performed using total lung RNA, after which expression values were computed from .CEL files by applying RMA normalization within sets of replicate samples. Statistical testing was performed using the significance analysis of microarrays algorithm. Statistically significant transcripts were validated by histochemical staining and quantitative polymerase chain reactions (PCR).
In mouse tissues, induced metastatic disease was found to be associated with reduced overall survival in older mice. The pattern of pulmonary metastases was more diffuse as compared to younger mice. Age-related transcriptional changes in the lung of extremely old hybrid mice were related to altered effectors of the immune system, regulators of angiogenesis and elements of DNA repair mechanisms, likely explaining the molecular basis behind the altered patterns of pulmonary metastasis observed in the extremely old mice.
In human tissues, eighty-two genes were differentially expressed in a statistically significantly manner. Most genes were downregulated in aged lung tissue and included collagen isoforms and proteins responsible for extracellular matrix synthesis and turnover. A single upregulated transcript was a MYC binding protein. Selected transcripts were validated by PCR and histochemical staining.
This is the first examination of lung metastases and the molecular biology of lung tissues at the extremes of age. Alterations to gene expression profiles was observed in both mouse and human lung tissues, and supports the concept of a field defect in normal lung tissues that develops with increased age.
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The Effects of Aging and Cognitive Strategies on Associative Memory: Not All Associations Are Created EqualDrouin, Héloïse January 2017 (has links)
Young adults often outperform older adults on tests of associative memory, however, the source of this age-related associative memory deficit is still under debate. There are two main non-mutually exclusive hypotheses: 1) impaired binding processes (i.e. creating and retrieving links between units of information) and; 2) impaired strategic processes (i.e. cognitive control processes that support encoding and retrieval). Although both components are thought to contribute uniquely and interact to support associative memory, they have rarely been studied together.
The primary goal of this dissertation is to further characterize associative memory deficits in healthy aging by measuring and controlling binding and strategic processes. Specifically, in this series of three experiments, we studied these two components concurrently by varying the level of demands on binding (i.e. comparing memory for different types of associations) and strategic processes (i.e. varying demands on self-initiated processes). A total N of 97 young adults and 94 older adults studied lists of object-pairs and object-location pairs under intentional encoding conditions. Demands on self-initiated processes were manipulated by increasing the number of foils at test (Experiment 1: 4 alternative forced-choice (AFC), vs. Experiment 2 & 3: 20AFC), and by providing strategy instructions in Experiment 3. We measured the production of strategies with trial-by-trial self-report. In all three experiments, we found that young adults outperformed older adults on object-object memory, but not on object-location memory. Older adults were just as proficient as young adults in generating strategies at study. This remained true even when demands on self-initiated processes increased. However, we found in all three experiments that young adults had greater strategy effectiveness (i.e. accuracy on pairs encoded with a strategy) on the object-object test. In contrast, performance on the object-location task was found to be less related to strategies. Our findings suggest that not all associations are equally affected by aging and that even when strategy production is equivalent between age groups older adults can still be impaired on associative memory.
The secondary goal of this dissertation was to explore the contribution of individual variability in age, general cognitive functioning, meta-memory and executive functioning on object-object and object-location memory, strategy production, and strategy effectiveness. Our results highlight the important contribution of executive functioning over and above any effects of age in explaining age-related associative memory decline.
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Comparação do equilíbrio estático e mobilidade entre idosos institucionalizados e moradores da comunidade /Faber, Livia Marcondes. January 2017 (has links)
Orientador: Marcos Eduardo Scheicher / Banca: Danielle dos Santos Cutrim Garros / Banca: Karina Gramani Say / Resumo: Objetivos: Comparar o equilíbrio estático e mobilidade de idosos institucionalizados com idosos moradores da comunidade. Métodos: Foram sujeitos da pesquisa 42 idosos, de 60 anos e mais, ambos os sexos, 21 residentes de instituições de longa permanência (ILPI), na cidade de Marília SP e 21 idosos moradores da comunidade. O equilíbrio estático (path lengh, velocidade média e área 95% da elipse) foi avaliado por uma plataforma de força e a mobilidade através do teste Timed Up and Go (TUG). Resultados: Os resultados mostraram que idosos do grupo ILPI's apresentaram valores significativamente maiores de oscilação do COP comparado com o grupo comunidade. Quanto à mobilidade, o grupo ILPI's apresentou maior tempo para realização do teste, indicando pior mobilidade em relação ao grupo comunidade. Conclusão: Idosos institucionalizados apresentaram mais oscilação do centro de gravidade e maior mobilidade do que idosos moradores da comunidade / Abstract: Objectives: To compare the static balance and mobility of institutionalized elderly with community-dwelling elderly. METHODS: were included in the study 42 elderly patients aged 60 and over, both sexes, 21 living in long-term care facilities (ILPI), in the city of Marília SP and 21 community-dwelling elderly. The static balance was evaluated by a force platform and mobility by the Timed Up and Go test (TUG). Results: The results showed that the elderly of the ILPI's group presented significantly higher values of COP oscillation compared to the community group. Regarding mobility, the ILPI's group presented longer time to perform the test, indicating worse mobility in relation to the community group. Conclusion: Institutionalized elderly showed more center of gravity oscillation and worse mobility than community-dwelling elderly / Mestre
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Absence of GIP secretion alleviates age-related obesity and insulin resistance / GIP分泌欠損は加齢に関連した肥満とインスリン抵抗性を軽減するKanemaru, Yoshinori 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22725号 / 医博第4643号 / 新制||医||1045(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 長船 健二, 教授 伊藤 貴浩, 教授 岩田 想 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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Almond as a model to explore epigenetic signatures associated with aging in perennial plantsWillman, Katherine Mary D'Amico 19 November 2021 (has links)
No description available.
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Avaliação morfofuncional do córtex adrenal em machos de gerbilo da Mongólia durante o envelhecimento /Zucão, Mariele Ilario January 2020 (has links)
Orientador: Patricia Simone Leite Vilamaior / Resumo: É conhecido que o processo de envelhecimento ocasiona em machos um desequilíbrio hormonal devido à redução gradual da síntese de testosterona pelos testículos, que afeta a maioria dos órgãos sensíveis a hormônios e dentre eles a adrenal, que é responsável pela síntese e secreção de hormônios esteroides como mineralocorticoides, glicocorticoides e andrógenos. Estudos anteriores reconhecem o importante papel da adrenal na regulação do sistema reprodutor e também é conhecido, por meio de estudos com castração, que esta é sensível à redução de andrógenos, no entanto, há pouco entendimento do papel dessa glândula no processo de andropausa e há uma dificuldade em encontrar modelos experimentais representativos, uma vez que há muitas diferenças morfofuncionais entre as adrenais dos roedores e primatas. As adrenais dos gerbilos da Mongólia têm características ultraestruturais peculiares que sugerem uma maior similaridade à dos primatas. Apesar de serem modelos experimentais utilizados em estudos de desregulação endócrina e do sistema reprodutor, há poucos estudos sobre a fisiologia do córtex adrenal dessa espécie. Considerando essa afirmação, esse estudo descreveu pela primeira vez a morfofisiologia da adrenal de gerbilos adultos e durante o envelhecimento, trazendo resultados que demonstram similaridades do córtex adrenal dessa espécie com o humano e de outros primatas, desde a morfologia à expressão de enzimas da biossíntese de cortisol e andrógenos e de receptores de andrógeno e e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aging process in males is known by occasioning a hormonal imbalance due to the gradual reduction in the testicular testosterone synthesis, which affects most of the organs sensitive to this hormone and, among them the, adrenal glands which its cortex is responsible to synthesize and secrete steroidogenic hormones as mineralocorticoids, glucocorticoids, and androgens. Existing research recognizes the significant role played by this gland in the regulation of the reproductive system; it is also known that it is sensitive to the reduction of testosterone caused by castration, although there is still very little scientific understanding of its role in the andropause process. Moreover, Mongolian gerbils are experimental models for studies in reproductive biology and endocrine deregulation, their adrenal glands present a peculiar structure and suggest having more similar morphophysiology to the primates than others rodents, although there have been few investigations about the gerbils' adrenocortical physiology. Considering this, this study has described the morphophysiology of this gland in gerbil for the first time and showed particular similarities between the adrenal cortex of M. unguiculatus and primates, since the morphology, to the expression of enzymes of cortisol and androgens biosynthesis and androgen and estrogen receptors. During aging was an hypertrophy in the adrenal cortex, based on the gradual increase in adrenal absolute weight of the adrenals in the older grou... (Complete abstract click electronic access below) / Mestre
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Legal Compliance in Guardianship Cases An Exploratory Study: Investigating Denton County Probate Court Visitors' Program Success with Legal Compliance in Guardianship Cases in 2013Dabner, Carol Patrice 12 1900 (has links)
Dabner, Carol P. Legal Compliance in Guardianship Cases. An Exploratory Study: Investigating Denton County Probate Court Visitors' Program Success with Legal Compliance in Guardianship Cases. Doctor of Philosophy (Applied Gerontology), December 2016, 140 pp., 18 tables, references, 20 titles.
Aim: To evaluate the effectiveness of the legal compliance of the Denton County Probate Court Visitor's program in the year 2013.
Rationale: Guardianship case management success is based on the presence of legal compliance of both guardians and the Court. When a guardian is legally compliant, a ward is receiving the statutorily minimum standards of care. Legal compliance equates (evidence of) the Ward receiving legally sufficient care. Research has not been vast; it has been consistent as to necessity of guardianship training, monitoring, and narrow focus of research. Evidence based research will assist in defining and developing appropriate court monitoring programs, which can add to the quality of care for elderly and disabled adults.
Methods: 1,300 guardianship cases in the probate court. Of these cases, 910 had annual reports of the person filed, which 304 were reviewed using the Legal Compliance Audit. Eight (8) factors of compliance were reviewed with three (3) being Court actions and five (5) being guardian actions.
Results: Exploratory study provides evidence based research of the necessary changes to develop the Denton County Probate Court Visitor's program. The guardians are more legal compliant than the Court.
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