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31.
The HIV-infected population is aging due to the success of combination antiretroviral therapy, which prolongs survival, as well as the growing number of newly diagnosed cases in adults 50 years old and over. HIV-infected individuals suffer from an accelerated aging due to the persistent and chronic activation of the immune system that leads to immune exhaustion and accelerated immunosenescence, even when on optimal immuno-virological control treatment. The clinical expression of the immunosenescence state is an increased prevalence of aging-related non-HIV associated comorbidities and a rising prevalence of frailty occurring earlier than in the general population. Thus, HIV-infected patients are biologically older than their chronological age, and they suffer from aging-related problems, such as frailty, which should be assessed.  相似文献   
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33.

Objectives

To estimate the values of the quality of life dimensions using the SF-12 questionnaire in the elderly on polymedication and with multiple morbidities, and identify the variables associated with it.

Material and methods

A cross-sectional study on a sample of 393 patients selected from the elderly population over 67 years and who took more than 5 drugs. The SF-12 was complemented by a personal interview in the clinic or in the home of the patient. Central tendency, dispersion, and the percentiles of the 8 dimensions were calculated, as well as the SF-36 physical and mental component summary measures (PCS and MCS). All patients below the 25th percentile of the PCS and MCS were classified as patients with a deterioration. Logistic regression was used to determine the variables that were associated with the deterioration in the quality of life.

Results

It is a population with high morbidity. The subjects showed very low scores on the general health scales −mean (SD): 25.7 (17.4)−; physical function −32.6 (32.1)−; and PCS: [(37.8 (25.1)]. Women had a worse quality of life than men in all the scales. Female sex, being over 80 years, frequent falls, chronic pain, cancerous disease, and depression, are variables that determine the health-related quality of life (HR-QoL).

Conclusion

This population has a poor HR-QoL, particularly in the physical dimensions. Chronic pain and depression, together with age and being female are variables that determine the deterioration in the HR-QoL.  相似文献   
34.

Introduction

The aim of this study was to analyse whether the activity is a protective factor of intellectual decline, and specifically to examine whether intellectual activity versus other activities, is a better predictor for the maintenance of cognitive functioning in a group of people over 90 years, independent in basic daily living activities and having preserved cognitive capacity.

Material and methods

This sample was selected from a bio-psycho-social longitudinal study of independent persons 90 and over. This is a longitudinal study involving 188 people, 67 males and 121 females. Measurements were taken of cognitive functioning and level of activity and repeated between 6 and 14 months; inferential analysis was performed at baseline and follow-up.

Results

At base-line, there is a strong association between the level of activity and performance. Also, and most important, intellectual activities at baseline predict cognitive functioning at follow-up. According to our results, intellectual activities and the maintenance of cognitive functioning are associated with the absence of cognitive impairment in the very elderly.

Conclusions

This has important implications for the scientific community in finding a predictive index and strategies, but also for the individual to identify factors of change on which to act to reduce problems associated with aging.  相似文献   
35.
中国梅花鹿地史分布、种和亚种的划分及演化历史   总被引:13,自引:1,他引:13  
郭延蜀  郑惠珍 《兽类学报》2000,20(3):168-179
对中国梅花鹿地史分布、种亚种的划分及其演化历史作了系统的研讨。认为从早更新世至现代,东亚季风区的梅花鹿应是一个多向度种,中国的梅花鹿可划分为9个亚种。指出梅花鹿可能在上新世晚期发源于我国的华北地区,更新世期间曾广泛公布于东北、华北、华中、华南、西南和青藏区的东部,全新世后其分布区急剧地缩减与更新世至全新世青藏高原的强烈抬升有关,但更主要的是受冰期后人类活动的影响。同时揭示了梅花鹿的演化谱系和我国野  相似文献   
36.
Modern life leads to a more active nocturnal lifestyle, reduced sleep hours and sometimes abrupt shifts across time zones (such as jet lag and shift work) that generate chronodisruption (CD) which can result in premature ageing. CD is defined as a significant disturbance of the internal temporal order of biochemical, physiological and behavioural circadian rhythms. Epidemiological studies show that CD induced by shift work, chronic jet lag, social jet lag and excessive exposure of bright light at night is associated with an increased incidence of metabolic syndrome, cardiovascular disease, cognitive and affective impairment, sleep disorders, some cancers and premature ageing. CD may be the result of disturbances in different components of the circadian system (central pacemaker and peripheral oscillators, inputs to central clock, mainly due to visual deficiencies, and output signals from the pacemaker and oscillators). Exposure to different synchronizers (light, meal times, physical and social activities) with a regular pattern results in a chronoenhacement that can prevent age-related CD.  相似文献   
37.
ObjectivesSirtuin 1 is a human protein involved in gene silencing and in inducing the deacetylation of proteins involved in the metabolic and adaptive response mechanisms. Polymorphisms in the SIRT1 gene have been studied with respect to aging. This study aims to determine the allelic and genotypic frequencies of the rs7895833 A/G polymorphism in the SIRT1 gene, and to identify the association between this polymorphism and the co-morbidities prevalent in the elderly population.Material and methodsA total of 216 patients were evaluated in an outpatient clinic in Central Brazil. The individuals underwent validated tests for cognitive impairment and falls risk, serum biochemistry analysis, as well as polymer chain reaction (PCR) with confronting two-pair primers for polymorphism genotyping.Resultsrs7895833 polymorphism in SIRT1 gene was observed in these patients as follows: AA (56/216), AG (138/216), and GG (22/216). The frequency of allele A was 0.58, and that of allele G was 0.42. In the multivariate analysis of the exploratory variables, glucose, high density lipoprotein (HDL) cholesterol, systemic arterial hypertension, dyslipidaemia, and depression, which were associated in the univariate analysis with the polymorphism rs7895833, only dyslipidaemia showed a statistically significant difference in a greater number of individuals with this polymorphism.ConclusionThe variant allele G of the SIRT1 gene polymorphism was found in 42% of these Brazilian geriatric patients, and was associated with dyslipidaemia. Further studies should be performed to confirm this result and to elucidate the role of SIRT1 in lipid metabolism.  相似文献   
38.
Most of the polypeptides of isolated brain synaptic junction preparations are cross-linked by disulfide bonds; these bonds are readily reformed following reduction by β-mercaptoethanol, suggesting that other, non-covalent interactions may hold the polypeptides in close contact. When synaptic junctions were treated with β-mercaptoethanol in conjunction with a large variety of reagents known to disrupt certain types of non-covalent bonds, however, the polypeptides could still be cross-linked. Furthermore, virtually all of these species remained associated with β-mercaptoethanol-reduced membrane in the presence of 0.05 N NaOH or 0.5% Triton X-100, although each of these solvents extracts large amounts of protein from extra-junctional membrane, which has a composition apparently similar to that of synaptic junctions.These results indicate that any non-covalent interactions existing among synaptic junction proteins are inaccessible to treatments at the surface of the membrane, being located within the lipid bilayer or perhaps at points of contact with sub-membranous arrays such as the post-synaptic density. Under special conditions, the polypeptides of extra-junctional membrane can also be induced to form disulfide cross-links among one another, and these bonds can likewise be rapidly reformed following reduction, giving this membrane properties similar to that of the junction. This suggests a model by which stabilized junctional membrane may be formed from fluid extra-junctional membrane during synaptogenesis.  相似文献   
39.
Researchers, stakeholders and policy makers agree about the importance of the population ageing in modern societies, so a broad analysis of current research strategies is in progress, such as FUTURAGE, a network for drawing a map for future research on ageing.  相似文献   
40.

Introduction

Currently there are notable differences in the aging of individuals in modern populations. While some of them enjoy a long healthy aging, others develop neurodegenerative diseases, such as Alzheimer's disease (AD). Environmental factors are critical, but genetics could explain the differences observed. It has recently been postulated that longevity genes might also be neuroprotective.

Objectives

To assess whether certain genetic variants associated with longevity might have a neuroprotective effect.

Methods

The subjects of this study are people older than 90 years. We will collect sociodemographic and clinical data and multiple assessments, cognitive, functional, anthropometric, nutritional, sensory and physical each participant. In addition, 64 SNPs loci distributed in 13 candidate genes FOXO3, SIRT1, TOMM40, APOE, PICALM, COMT, CETP, CLU, CR1, IL-6, PCK-1, ZNF224 and ACE will be analysed by Taqman array.

Results

It is hoped to gain more knowledge about under/over-represented alleles in nonagenarians. Furthermore, comparison of the genetic characteristics of nonagenarians with AD with those free of disease will enable links to be seen between certain alleles with protection or the risk of AD. Associated information on the participants will create subgroups showing the interactions between environment and genetic variation in relation to healthy aging and AD.

Conclusion

The study of the genetic variability of nonagenarians can give us information on the alleles associated with longevity and neuroprotection.  相似文献   
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