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51.
This study aimed to determine the impact of community sense, depression and interpersonal needs on attitude towards ageing among older adults. This is a cross-sectional and correlational study. From December 2018 to June 2019, 211 community-dwelling older adults from a mid-sized city in Korea participated in the study. The results showed a significant interpersonal needs path from depression and community sense to attitude towards ageing. When interpersonal needs were mediated, the indirect effect of both depression and community sense on attitude towards ageing was significant. Interpersonal needs had a significant mediating effect on the relationships between attitude towards ageing and community sense and depression. The results of this study showed the effects of socio-psychological factors on attitude towards ageing, which is a known indicator of successful ageing and quality of life improvement in older adults. Based on this study, we suggest that the development of programs to promote successful ageing should include strategies to improve community sense, interpersonal needs fulfilment and interventions to reduce depression.  相似文献   
52.
The current study was designed to further clarify the influence of brain morphology, sleep oscillatory activity and age on memory consolidation. Specifically, we hypothesized, that a smaller volume of hippocampus, parahippocampal and medial prefrontal cortex negatively impacts declarative, but not procedural, memory consolidation. Explorative analyses were conducted to demonstrate whether a decrease in slow‐wave activity negatively impacts declarative memory consolidation, and whether these factors mediate age effects on memory consolidation. Thirty‐eight healthy participants underwent an acquisition session in the evening and a retrieval session in the morning after night‐time sleep with polysomnographic monitoring. Declarative memory was assessed with the paired‐associate word list task, while procedural memory was tested using the mirror‐tracing task. All participants underwent high‐resolution magnetic resonance imaging. Participants with smaller hippocampal, parahippocampal and medial prefrontal cortex volumes displayed a reduced overnight declarative, but not procedural memory consolidation. Mediation analyses showed significant age effects on overnight declarative memory consolidation, but no significant mediation effects of brain morphology on this association. Further mediation analyses showed that the effects of age and brain morphology on overnight declarative memory consolidation were not mediated by polysomnographic variables or sleep electroencephalogram spectral power variables. Thus, the results suggest that the association between age, specific brain area volume and overnight memory consolidation is highly relevant, but does not necessarily depend on slow‐wave sleep as previously conceptualized.  相似文献   
53.
Human skin undergoes morphological, biochemical and functional modifications during the ageing process. This study was designed to produce a 3‐dimensional (3D) skin equivalent in vitro reflecting some aspects of in vivo aged skin. Reconstructed skin was generated by co‐culturing skin fibroblasts and keratinocytes on a collagen–glycosaminoglycan–chitosan scaffold, and ageing was induced by the exposition of fibroblasts to Mitomycin‐C (MMC). Recently published data showed that MMC treatment resulted in a drug‐induced accelerated senescence (DIAS) in human dermal fibroblast cultures. Next to established ageing markers, histological changes were analysed in comparison with in vivo aged skin. In aged epidermis, the filaggrin expression is reduced in vivo and in vitro. Furthermore, in dermal tissue, the amount of elastin and collagen is lowered in aged skin in vivo as well as after the treatment of 3D skin equivalents with MMC in vitro. Our results show histological signs and some aspects of ageing in a 3D skin equivalent in vitro, which mimics aged skin in vivo.  相似文献   
54.
Abstract

Aim: The aim of this study was to describe experiences of limitations in occupational performance and strategies for managing daily activities among the elderly with chronic heart failure (CHF). Methods: Ten participants from primary healthcare with a confirmed diagnosis of CHF were interviewed. The interviews were analysed using qualitative content analysis. Results: The first theme, “Redefining an active life, aware of one’s impaired body”, was based on four sub-themes: realizing one’s limited activity ability; striving to preserve an active life; focusing on meaningful activities; and changing vs. not changing habits and roles. The second theme, “Planning activities and balancing the degree of effort”, was based on three sub-themes: limiting, organizing, and rationalizing activities; adjusting activities to today’s ability; and using technology and adapting the environment. Conclusions: Elderly people with CHF are struggling with an ongoing process of occupational adaptation due to periodical physical decline and fluctuating day-to-day ability. This highlights a need for information on strategies from a holistic perspective and client-centred occupational therapy interventions.  相似文献   
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This systematic review investigated whether the insulin sensitiser metformin has a geroprotective effect in humans. Pubmed and Embase were searched along with databases of unpublished studies. Eligible research investigated the effect of metformin on all-cause mortality or diseases of ageing relative to non-diabetic populations or diabetics receiving other therapies with adjustment for disease control achieved. Overall, 260 full-texts were reviewed and 53 met the inclusion criteria. Diabetics taking metformin had significantly lower all-cause mortality than non-diabetics (hazard ratio (HR) = 0.93, 95%CI 0.88–0.99), as did diabetics taking metformin compared to diabetics receiving non-metformin therapies (HR = 0.72, 95%CI 0.65–0.80), insulin (HR = 0.68, 95%CI 0.63–0.75) or sulphonylurea (HR = 0.80, 95%CI 0.66–0.97). Metformin users also had reduced cancer compared to non-diabetics (rate ratio = 0.94, 95%CI 0.92–0.97) and cardiovascular disease (CVD) compared to diabetics receiving non-metformin therapies (HR = 0.76, 95%CI 0.66–0.87) or insulin (HR = 0.78, 95%CI 0.73–0.83). Differences in baseline characteristics were observed which had the potential to bias findings, although statistical adjustments were made. The apparent reductions in all-cause mortality and diseases of ageing associated with metformin use suggest that metformin could be extending life and healthspans by acting as a geroprotective agent.  相似文献   
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58.
The dermis can be divided into two morphologically different layers: the papillary and reticular dermis. Fibroblasts isolated from these layers behave differently when cultured in vitro. During skin ageing, the papillary dermis decreases in volume. Based on the functional differences in vitro, it is hypothesized that the loss of papillary fibroblasts contributes to skin ageing. In this study, we aimed to mimic certain aspects of skin ageing by using high‐passage cultures of reticular and papillary fibroblasts and investigated the effect of these cells on skin morphogenesis in reconstructed human skin equivalents. Skin equivalents generated with reticular fibroblasts showed a reduced terminal differentiation and fewer proliferating basal keratinocytes. Aged in vitro papillary fibroblasts had increased expression of biomarkers specific to reticular fibroblasts. The phenotype and morphology of skin equivalents generated with high‐passage papillary fibroblasts resembled that of reticular fibroblasts. This demonstrates that papillary fibroblasts can differentiate into reticular fibroblasts in vitro. Therefore, we hypothesize that papillary fibroblasts represent an undifferentiated phenotype, while reticular fibroblasts represent a more differentiated population. The differentiation process could be a new target for anti‐skin‐ageing strategies.  相似文献   
59.
The field of ageing research has been rapidly advancing in recent decades and it had provided insight into the complexity of ageing phenomenon. However, as the organism-environment interaction appears to significantly affect the organismal pace of ageing, the systematic approach for gerontogenic risk assessment of environmental factors has yet to be established. This puts demand on development of effective biomarker of ageing, as a relevant tool to quantify effects of gerontogenic exposures, contingent on multidisciplinary research approach.Here we review the current knowledge regarding the main endogenous gerontogenic pathways involved in acceleration of ageing through environmental exposures. These include inflammatory and oxidative stress-triggered processes, dysregulation of maintenance of cellular anabolism and catabolism and loss of protein homeostasis. The most effective biomarkers showing specificity and relevancy to ageing phenotypes are summarized, as well. The crucial part of this review was dedicated to the comprehensive overview of environmental gerontogens including various types of radiation, certain types of pesticides, heavy metals, drugs and addictive substances, unhealthy dietary patterns, and sedentary life as well as psychosocial stress. The reported effects in vitro and in vivo of both recognized and potential gerontogens are described with respect to the up-to-date knowledge in geroscience. Finally, hormetic and ageing decelerating effects of environmental factors are briefly discussed, as well.  相似文献   
60.
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