811 resultados para age-related macular degeneration


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Down syndrome (DS) or Trisomy 21, occurring in 1/700 and 1/1000 livebirths, is the most common genetic disorder, characterized by a third copy of the human chromosome 21 (Hsa21). DS is associated with various defects, including congenital heart diseases, craniofacial abnormalities, immune system dysfunction, mental retardation (MR), learning and memory deficiency. The phenotypic features in DS are a direct consequence of overexpression of genes located within the triplicated region on Hsa21. In addition to developmental brain abnormalities and disabilities, people with DS by the age of 30-40 have a greatly increased risk of early-onset of Alzheimer’s disease (AD) and an apparent tendency toward premature aging. Many of the immunological anomalies in DS can be enclosed in the spectrum of multiple signs of early senescence. People with DS have an increased vulnerability to oxidative damage and many factors, including amyloid beta protein (Abeta), genotype ApoE4, oxidative stress, mutations in mitochondrial DNA (mtDNA), impairment of antioxidant enzymes, accelerated neuronal cell apoptosis, are related to neuronal degeneration and early aging in DS. SUBJECTS and METHODS: Since 2007 a population of 50 adolescents and adults with DS, 26 males and 24 females (sex-ratio: M/F = 1.08), has been evaluated for the presence of neurological features, biomarkers and genetic factors correlated with neuronal degeneration and premature aging. The control group was determined by the mother and the siblings of the patients. A neuropsychiatric evaluation was obtained from all patients. The levels of thyroid antibodies (antiTg and antiTPO) and of some biochemical markers of oxidative stress, including homocysteine (tHcy), uric acid, cobalamin, folate were measured. All patients, the mother and the siblings were genotyped for ApoE gene. RESULTS: 40% of patients, with a mild prevalence of females aged between 19 and 30 years, showed increased levels of antiTg and antiTPO. The levels of tHcy were normal in 52% patients and mildly increased in 40%; hyperomocysteinemia was associated with normal levels of thyroid antibodies in 75% of patients (p<0.005). The levels of uric acid were elevated in 26%. Our study showed a prevalence of severe MR in patients aged between 1-18 years and over 30 years. Only 3 patients, 2 females and one male, over 30 years of age, showed dementia. According to the literature, the rate of Down left-handers was high (25%) compared to the rest of population and the laterality was associated with increased levels of thyroid antibodies (70%). 21.5% of patients were ApoE4 positive (ApoE4+) with a mean/severe MR. CONCLUSIONS: Until now no biochemical evidence of oxidative damage and no deficiency or alteration of antioxidant function in our patients with DS were found. mtDNA sequencing could show some mutations age-related and associated with oxidative damage and neurocognitive decline in the early aging of DS. The final aim is found predictive markers of early-onset dementia and a target strategy for the prevention and the treatment of diseases caused by oxidative stress. REFERENCES: 1) Rachidi M, Lopes C: “Mental retardation and associated neurological dysfunctions in Down syndrome: a consequence of dysregulation in critical chromosome 21 genes and associated molecular pathways.” - Eur J Paediatr Neurol. May;12(3):168-82 (2008). 2) Lott IT, Head E: “Down syndrome and Alzheimer's disease: a link between development and aging.” - Ment Retard Dev Disabil Res Rev, 7(3):172-8 (2001). 3) Lee HC, Wei YH: “Oxidative Stress, Mitochondrial DNA Mutation, and Apoptosis in Aging.” - Exp Biol Med (Maywood), May;232(5):592-606 (2007).

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The aging process is characterized by the progressive fitness decline experienced at all the levels of physiological organization, from single molecules up to the whole organism. Studies confirmed inflammaging, a chronic low-level inflammation, as a deeply intertwined partner of the aging process, which may provide the “common soil” upon which age-related diseases develop and flourish. Thus, albeit inflammation per se represents a physiological process, it can rapidly become detrimental if it goes out of control causing an excess of local and systemic inflammatory response, a striking risk factor for the elderly population. Developing interventions to counteract the establishment of this state is thus a top priority. Diet, among other factors, represents a good candidate to regulate inflammation. Building on top of this consideration, the EU project NU-AGE is now trying to assess if a Mediterranean diet, fortified for the elderly population needs, may help in modulating inflammaging. To do so, NU-AGE enrolled a total of 1250 subjects, half of which followed a 1-year long diet, and characterized them by mean of the most advanced –omics and non –omics analyses. The aim of this thesis was the development of a solid data management pipeline able to efficiently cope with the results of these assays, which are now flowing inside a centralized database, ready to be used to test the most disparate scientific hypotheses. At the same time, the work hereby described encompasses the data analysis of the GEHA project, which was focused on identifying the genetic determinants of longevity, with a particular focus on developing and applying a method for detecting epistatic interactions in human mtDNA. Eventually, in an effort to propel the adoption of NGS technologies in everyday pipeline, we developed a NGS variant calling pipeline devoted to solve all the sequencing-related issues of the mtDNA.

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X-linked retinoschisis (XLRS) is one of the most common causes of macular degeneration in young men. The purpose of this study was to use optical coherence tomography combined with ophthalmoscopy to study the effects of aging on the morphologic changes associated with XLRS.

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Abstract. This article provides the reader with practical information to be applied to the various remaining causes of macular edema. Some macular edemas linked to ocular diseases like radiotherapy after ocular melanomas remained of poor functional prognosis due to the primary disease. On the contrary, macular edemas occurring after retinal detachment or after some systemic or local treatment use are often temporary. Macular edema associated with epiretinal membranes or vitreomacular traction is the main cause of poor functional recovery. However, the delay to observe a significant improvement of vision after surgery should be long, as usually observed in tractional myopic vitreoschisis. Finally, some circumstances of macular edemas such as hemangiomas or macroaneurysms should be treated, if symptomatic, with the treatments currently used in diabetic macular edema or exudative macular degeneration.

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This chapter provides the reader with practical information to be applied to the various remaining causes of macular edema. Some clinical cases of macular edema linked to ocular diseases like postradiotherapy for ocular melanomas remained of poor functional prognosis due to the primary disease. On the contrary, macular edema occurring after retinal detachment or after diverse systemic or local treatment use is often temporary. Macular edema associated with epiretinal membranes or vitreomacular traction is the main cause of poor functional recovery. In other cases, as in tractional myopic vitreoschisis, the delay to observe a significant improvement of the vision after surgery should be long. Finally, macular edema associated with hemangiomas or macroaneurysms should be treated, if symptomatic, using the same current treatment as in diabetic macular edema or exudative macular degeneration.

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The examination of telomere dynamics is a recent technique in ecology for assessing physiological state and age-related traits from individuals of unknown age. Telomeres shorten with age in most species and are expected to reflect physiological state, reproductive investment, and chronological age. Loss of telomere length is used as an indicator of biological aging, as this detrimental deterioration is associated with lowered survival. Lifespan dimorphism and more rapid senescence in the larger, shorter-lived sex are predicted in species with sexual size dimorphism, however, little is known about the effects of behavioral dimorphism on senescence and life history traits in species with sexual monomorphism. Here we compare telomere dynamics of thick-billed murres (Uria lomvia), a species with male-biased parental care, in two ways: 1) cross-sectionally in birds of known-age (0-28 years) from one colony and 2) longitudinally in birds from four colonies. Telomere dynamics are compared using three measures: the telomere restriction fragment (TRF), a lower window of TRF (TOE), and qPCR. All showed age-related shortening of telomeres, but the TRF measure also indicated that adult female murres have shorter telomere length than adult males, consistent with sex-specific patterns of ageing. Adult males had longer telomeres than adult females on all colonies examined, but chick telomere length did not differ by sex. Additionally, inter-annual telomere changes may be related to environmental conditions; birds from a potentially low quality colony lost telomeres, while those at more hospitable colonies maintained telomere length. We conclude that sex-specific patterns of telomere loss exist in the sexually monomorphic thick-billed murre but are likely to occur between fledging and recruitment. Longer telomeres in males may be related to their homogamous sex chromosomes (ZZ) or to selection for longer life in the care-giving sex. Environmental conditions appeared to be the primary drivers of annual changes in adult birds.

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OBJECTIVES: We investigated whether qualitative or quantitative alterations of the endothelial progenitor cell (EPC) pool predict age-related structural vessel wall changes. BACKGROUND: We have previously shown that age-related endothelial dysfunction is accompanied by qualitative rather than quantitative changes of EPCs. Animal studies suggest that impaired EPC functions lead to accelerated arterial intimal thickening. METHODS: Intima-media thickness (IMT) was measured in the common carotid artery in our previously published groups of younger (25 +/- 1 years, n = 20) and older (61 +/- 2 years, n = 20) healthy non-smoking volunteers without arterial hypertension, hypercholesterolemia, and diabetes mellitus. Endothelial progenitor cells (EPCs, KDR(+)/CD34(+) and KDR(+)/CD133(+)) were counted in peripheral blood using flow cytometry. In ex vivo expanded EPCs, the function was determined as chemotaxis to VEGF, proliferation, and survival. RESULTS: We observed thicker IMT in older as compared to younger subjects (0.68 +/- 0.03 mm Vs. 0.48 +/- 0.02 mm, P < 0.001). Importantly, there were significant inverse univariate correlations between IMT, EPC chemotaxis, and survival (r = -0.466 P < 0.05; r = -0.463, P < 0.01). No correlation was observed with numbers of circulating EPCs. Multivariate regression analysis revealed that age, mean arterial pressure and migration of EPCs were independent predictors of IMT (R (2 )= 0.58). CONCLUSION: Impaired EPC function may lead to accelerated vascular remodeling due to chronic impairment of endothelial maintenance.

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BACKGROUND: The prevalence of arterial hypertension lacking a defined underlying cause increases with age. Age-related arterial hypertension is insufficiently understood, yet known characteristics suggest an aldosterone-independent activation of the mineralocorticoid receptor. Therefore, we hypothesized that 11beta-HSD2 activity is age-dependently impaired, resulting in a compromised intracellular inactivation of cortisol (F) with F-mediated mineralocorticoid hypertension. METHODS: Steroid hormone metabolites in 24-h urine samples of 165 consecutive hypertensive patients were analyzed for F and cortisone (E), and their TH-metabolites tetrahydro-F (THF), 5alphaTHF, TH-deoxycortisol (THS), and THE by gas chromatography-mass spectroscopy. Apparent 11beta-HSD2 and 11beta-hydroxylase activity and excretion of F metabolites were assessed. RESULTS: In 72 female and 93 male patients aged 18-84 years, age correlated positively with the ratios of (THF + 5alphaTHF)/THE (P = 0.065) and F/E (P < 0.002) suggesting an age-dependent reduction in the apparent 11beta-HSD2 activity, which persisted (F/E; P = 0.020) after excluding impaired renal function. Excretion of F metabolites remained age-independent most likely as a consequence of an age-dependent diminished apparent 11beta-hydroxylase activity (P = 0.038). CONCLUSION: Reduced 11beta-HSD2 activity emerges as a previously unrecognized risk factor contributing to the rising prevalence of arterial hypertension in elderly. This opens new perspectives for targeted treatment of age-related hypertension.

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Background: Semantic memory processes have been well described in literature. However, the available findings are mostly based on relatively young subjects and concrete word material (e.g. tree). Comparatively little information exists about semantic memory for abstract words (e.g. mind) and possible age related changes in semantic retrieval. In this respect, we developed a paradigm that is useful to investigate the implicit (i.e. attentionindependent) access to concrete and abstract semantic memory. These processes were then compared between young and elderly healthy subjects. Methods: A well established tool for investigating semantic memory processes is the semantic priming paradigm, which consists both of semantically unrelated and related word pairs. In our behavioral task these noun-noun word pairs were further divided into concrete, abstract and matched pronounceable non-word conditions. With this premise, the young and elderly participants performed a lexical decision task: they were asked to press a choice of two buttons as an indication for whether the word pair contained a non-word or not. In order to minimize controlled (i.e. attention-dependent) retrieval strategies, a short stimulus onset asynchrony (SOA) of 150ms was set. Reaction time (RT) changes and accuracy to related and unrelated words (priming effect) in the abstract vs. concrete condition (concreteness effect) were the dependent variables of interest. Results and Discussion: Statistical analysis confirmed both a significant priming effect (i.e. shorter RTs in semantically related compared to unrelated words) and a concreteness effect (i.e. RT decrease for concrete compared to abstract words) in the young and elderly subjects. There was no age difference in accuracy. The only age effect was a commonly known general slowing in RT over all conditions. In conclusion, age is not a critical factor in the implicit access to abstract and concrete semantic memory.

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Life expectancy continuously increases but our society faces age-related conditions. Among musculoskeletal diseases, osteoporosis associated with risk of vertebral fracture and degenerative intervertebral disc (IVD) are painful pathologies responsible for tremendous healthcare costs. Hence, reliable diagnostic tools are necessary to plan a treatment or follow up its efficacy. Yet, radiographic and MRI techniques, respectively clinical standards for evaluation of bone strength and IVD degeneration, are unspecific and not objective. Increasingly used in biomedical engineering, CT-based finite element (FE) models constitute the state-of-art for vertebral strength prediction. However, as non-invasive biomechanical evaluation and personalised FE models of the IVD are not available, rigid boundary conditions (BCs) are applied on the FE models to avoid uncertainties of disc degeneration that might bias the predictions. Moreover, considering the impact of low back pain, the biomechanical status of the IVD is needed as a criterion for early disc degeneration. Thus, the first FE study focuses on two rigid BCs applied on the vertebral bodies during compression test of cadaver vertebral bodies, vertebral sections and PMMA embedding. The second FE study highlights the large influence of the intervertebral disc’s compliance on the vertebral strength, damage distribution and its initiation. The third study introduces a new protocol for normalisation of the IVD stiffness in compression, torsion and bending using MRI-based data to account for its morphology. In the last study, a new criterion (Otsu threshold) for disc degeneration based on quantitative MRI data (axial T2 map) is proposed. The results show that vertebral strength and damage distribution computed with rigid BCs are identical. Yet, large discrepancies in strength and damage localisation were observed when the vertebral bodies were loaded via IVDs. The normalisation protocol attenuated the effect of geometry on the IVD stiffnesses without complete suppression. Finally, the Otsu threshold computed in the posterior part of annulus fibrosus was related to the disc biomechanics and meet objectivity and simplicity required for a clinical application. In conclusion, the stiffness normalisation protocol necessary for consistent IVD comparisons and the relation found between degeneration, mechanical response of the IVD and Otsu threshold lead the way for non-invasive evaluation biomechanical status of the IVD. As the FE prediction of vertebral strength is largely influenced by the IVD conditions, this data could also improve the future FE models of osteoporotic vertebra.

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People differ in how open-ended or limited they perceive their future. We argue that individual differences in future time perspective affect the activation of implicit motives. Perceiving the time remaining for the satisfaction of one’s motives as limited should be associated with a higher activation of these motives than perceiving one’s future as more open-ended. Given that future time perspective decreases across adulthood, older adults should score higher on implicit motives than younger adults. This hypothesis was supported in a study with young (n = 53, age M = 25.60 years) and older adults (n = 55, age M = 68.05 years). Additionally, an experimental manipulation of future time perspective showed that age-related differences in implicit motives are influenced by future time perspective. These findings demonstrate that future time perspective is an important factor to explain the strength of motives.

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OBJECTIVES: The present research examined motivational differences across adulthood that might contribute to age-related differences in the willingness to engage in collective action. Two experiments addressed the role of gain and loss orientation for age-related differences in the willingness to engage in collective action across adulthood. METHOD: In Experiment 1, N = 169 adults (20-85 years) were confronted with a hypothetical scenario that involved either an impending increase or decrease of health insurance costs for their respective age group. In Experiment 2, N = 231 adults (18-83 years) were asked to list an advantage or disadvantage they perceived in being a member of their age group. Subsequently, participants indicated their willingness to engage in collective action on behalf of their age group. RESULTS: Both experiments suggest that, with increasing age, people are more willing to engage in collective action when they are confronted with the prospect of loss or a disadvantage. DISCUSSION: The findings highlight the role of motivational processes for involvement in collective action across adulthood. With increasing age, (anticipated) loss or perceived disadvantages become more important for the willingness to participate in collective action.

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The currently presented large dataset (n = 1,422) consists of results that have been assembled over the last 8 years at science fairs using the 16-item odor identification part of the "Sniffin' Sticks". In this context, the focus was on olfactory function in children; in addition before testing, we asked participants to rate their olfactory abilities and the patency of the nasal airways. We reinvestigated some simple questions, e.g., differences in olfactory odor identification abilities in relation to age, sex, self-ratings of olfactory function and nasal patency. Three major results evolved: first, consistent with previously published reports, we found that identification scores of the youngest and the oldest participants were lower than the scores obtained by people aged 20-60. Second, we observed an age-related increase in the olfactory abilities of children. Moreover, the self-assessed olfactory abilities were related to actual performance in the smell test, but only in adults, and self-assessed nasal patency was not related to the "Sniffin' Sticks" identification score.

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Introduction: The objective of this study was to define age-related changes in the human smile. The areas of interest were: upper lip length at smile and repose, upper lip thickness at smile and repose, maxillary incisal display at smile, interlabial gap height at smile, smile index, percent buccal corridors, intercommissural width at rest, smile height, and smile arc. A secondary objective was to study the perioral changes from rest to smile and compare them on the basis of age. Materials and Method: Video equipment was used to capture video for 261 subjects. Two frames for each subject were selected; one frame representing the lips and rest and the second representing the widest smile. After excluding 40 subjects the data for the remaining 221 subjects was analyzed. Results: There was a decrease of 1.5 to 2 mm in the maxillary incisor display during smile, with increase in age. Smile index significantly increased with increase in age. Most (78%) subjects displayed an average smile height. No subjects in the 50 and over age group displayed a high smile while no subjects in the 15-19 year old age group presented with a low smile. All the dynamic measures indicated there was a pattern of decreasing change from rest to smile especially evident after the 30-39 year old age group. Conclusions: This study helps to establish age related dynamic norms. As the person ages the smile gets narrower vertically and wider transversely. The dynamic measures indicate that the muscles' ability to create a smile decreases with increasing age.

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The concept of cognitive reserve (CR) describes the mind’s resistance to the progressive damage of the brain and probably this can be reflected as the ability to recruit brain networks in an effective way. It is as- sociated with the abilityto copewith the deleterious effects of brain damage,brain degeneration, or age-related changes on cognitive performance.