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Chronic lithium treatment diminishes the female advantage in lifespan in Drosophila melanogaster
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Fengge Zhu Qinggang Li Fujian Zhang Xuefeng Sun Guangyan Cai Weiguang Zhang Xiangmei Chen 《Clinical and experimental pharmacology & physiology》2015,42(6):617-621
Two studies have concluded that lithium exposure extends the lifespan of Caenorhabditis elegans. However, the effect of lithium on another widely used model organism, Drosophila melanogaster, remains unclear. Here, we demonstrate that chronic treatment with a low to moderate dose of lithium chloride does not extend lifespan in D. melanogaster and that the drug abolishes the female lifespan advantage in flies. 相似文献
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Ethical implications of home telecare for older people: a framework derived from a multisited participative study
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Maggie Mort PhD Celia Roberts PhD Jeannette Pols PhD Miquel Domenech PhD Ingunn Moser PhD The EFORTT investigators 《Health expectations》2015,18(3):438-449
Context
Telecare and telehealth developments have recently attracted much attention in research and service development contexts, where their evaluation has predominantly concerned effectiveness and efficiency. Their social and ethical implications, in contrast, have received little scrutiny.Objective
To develop an ethical framework for telecare systems based on analysis of observations of telecare‐in‐use and citizens’ panel deliberations.Design
Ethnographic study (observation, work shadowing), interviews, older citizens’ panels and a participative conference.Setting
Participants’ homes, workplaces and familiar community venues in England, Spain, the Netherlands and Norway 2008–2011.Results
Older respondents expressed concerns that telecare might be used to replace face‐to‐face/hands‐on care to cut costs. Citizens’ panels strongly advocated ethical and social questions being considered in tandem with technical and policy developments. Older people are too often excluded from telecare system design, and installation is often wrongly seen as a one‐off event. Some systems enhance self‐care by increasing self‐awareness, while others shift agency away from the older person, introducing new forms of dependency.Conclusions
Telecare has care limitations; it is not a solution, but a shift in networks of relations and responsibilities. Telecare cannot be meaningfully evaluated as an entity, but rather in the situated relations people and technologies create together. Characteristics of ethical telecare include on‐going user/carer engagement in decision making about systems: in‐home system evolution with feedback opportunities built into implementation. System design should be horizontal, ‘two‐way’/interactive rather than vertical or ‘one‐way’. An ethical framework for telecare has been developed from these conclusions (Table 1). 相似文献64.
AIMS: Autonomic function (AF) is attenuated by heart failure (HF). Reports have been based on studies of young patients with systolic heart failure (SHF). However, HF is a disease of older patients who are more likely to have diastolic heart failure (DHF). We investigated whether age alters AF in elderly HF patients and whether the haemodynamic type of HF influences AF. METHOD AND RESULTS: Thirty-six elderly HF (Framingham criteria) patients (11 with SHF, 25 with DHF) and 21 matched healthy subjects underwent simple bedside AF tests. Compared with the reference values for healthy adults, the mean E:I ratios and the median 30:15 ratios standing were all essentially normal. The median 30:15 ratios tilt and the mean Valsalva ratios were all significantly below the reference value (P for all cases <0.050). Comparing three groups, there were no significant differences for mean E:I ratio (P=0.111), 30:15 tilt (P=0.619) and 30:15 standing (P=0.167), whereas there were significant differences for the mean Valsalva ratios (P=0.001). The mean Valsalva ratio of the SHF patients was significantly lower than that for the DHF patients (P<0.001) which in turn was significantly lower than the result of the healthy subjects (P<0.001). CONCLUSION: There is an age-related impairment in AF with further impairment occurring in patients with HF. However, the severity of autonomic dysfunction is less in patients with DHF compared with patients with SHF. 相似文献
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R. W. J. Meijers N. H. R. Litjens E. A. de Wit A. W. Langerak A. van der Spek C. C. Baan W. Weimar M. G. H. Betjes 《Clinical and experimental immunology》2013,174(3):424-432
Cytomegalovirus (CMV) infection has been implicated in accelerated T cell ageing. End‐stage renal disease (ESRD) patients have a severely immunologically aged T cell compartment but also a high prevalence of CMV infection. We investigated whether CMV infection contributes to T cell ageing in ESRD patients. We determined the thymic output by the T cell receptor excision circle (TREC) content and percentage of CD31+ naïve T cells. The proliferative history of the T cell compartment by determination of the relative telomere length (RTL) and the T cell differentiation status was determined by immunophenotyping. It appeared that CMV infection did not affect thymic output but reduced RTL of CD8+ T cells in ESRD patients. Moreover, increased T cell differentiation was observed with higher percentages of CD57+ and CD28null CD4+ and CD8+ memory T cells. These CD28null T cells had significantly shorter telomeres compared to CD28+ T cells. Therefore we concluded that CMV infection does not affect the decreased thymic output but increases T cell differentiation as observed in ESRD‐related premature T cell ageing. 相似文献
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Svenja M. Spuling Verena Klusmann Catherine E. Bowen Anna E. Kornadt Eva-Marie Kessler 《European journal of ageing》2020,17(4):445
Although a large body of research has demonstrated the predictive power of subjective ageing for several decisive developmental outcomes, there remains some controversy about whether subjective ageing truly represents a unique construct. Thus, information about the convergent and discriminant validity of different approaches to measuring subjective ageing is still critically needed. Using data from the 2014 wave of the German Ageing Survey, we examined how three established subjective ageing measures (subjective age, global attitude toward own ageing, multidimensional ageing-related cognitions) were inter-related as well as distinct from general dispositions (optimism, self-efficacy) and well-being (negative affect, depressive symptoms, self-rated health). Using correlational and multivariate regression analysis, we found that the three subjective ageing measures were significantly inter-related (r = |.09| to |.30|), and that each measure was distinct from general dispositions and well-being. The overlap with dispositional and well-being measures was lowest for subjective age and highest for global attitudes towards own ageing. The correlation between global attitudes towards own ageing and optimism was particularly striking. Despite the high convergent validity of the different dimensions of ageing cognitions, we nevertheless observed stronger associations between specific dimensions of ageing cognitions with negative affect and self-rated health. We conclude that researchers should be aware of the multidimensional nature of subjective ageing. Furthermore, subjective age appears to be a highly aggregated construct and future work is needed to clarify its correlates and reference points.Electronic supplementary materialThe online version of this article (10.1007/s10433-019-00529-7) contains supplementary material, which is available to authorized users. 相似文献
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