878 resultados para Age-related diseases


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Targeted angiostatic therapy receives major attention for the treatment of cancer and exudative age-related macular degeneration (AMD). Photodynamic therapy (PDT) has been used as an effective clinical approach for these diseases. As PDT can cause an angiogenic response in the treated tissue, combination of PDT with anti-angiogenic compounds should lead to improved therapy. This study was undertaken to test the clinically used small molecule kinase inhibitors Nexavar® (sorafenib), Tarceva® (erlotinib) and Sutent® (sunitinib) for this purpose, and to compare the results to the combination of Visudyne®-PDT with Avastin® (bevacizumab) treatment. When topically applied to the chicken chorioallantoic membrane at embryo development day (EDD) 7, a clear inhibition of blood vessel development was observed, with sorafenib being most efficient. To investigate the combination with phototherapy, Visudyne®-PDT was first applied on EDD11 to close all <100 μm vessels. Application of angiostatics after PDT resulted in a significant decrease in vessel regrowth in terms of reduced vessel density and number of branching points/mm(2) . As the 50% effective dose (ED50) for all compounds was approximately 10-fold lower, Sorafenib outperformed the other compounds. In vitro, all kinase inhibitors decreased the viability of human umbilical vein endothelial cells. Sunitinib convincingly inhibited the in vitro migration of endothelial cells. These results suggest the therapeutic potential of these compounds for application in combination with PDT in anti-cancer approaches, and possibly also in the treatment of other diseases where angiogenesis plays an important role.

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Age trajectories for personality traits are known to be similar across cultures. To address whether stereotypes of age groups reflect these age-related changes in personality, we asked participants in 26 countries (N = 3,323) to rate typical adolescents, adults, and old persons in their own country. Raters across nations tended to share similar beliefs about different age groups; adolescents were seen as impulsive, rebellious, undisciplined, preferring excitement and novelty, whereas old people were consistently considered lower on impulsivity, activity, antagonism, and Openness. These consensual age group stereotypes correlated strongly with published age differences on the five major dimensions of personality and most of 30 specific traits, using as criteria of accuracy both self-reports and observer ratings, different survey methodologies, and data from up to 50 nations. However, personal stereotypes were considerably less accurate, and consensual stereotypes tended to exaggerate differences across age groups.

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Neurofilamentous changes in select groups of neurons are associated with the degenerative changes of many human age-related neurodegenerative diseases. To examine the possible effects of aging on the neuronal cytoskeleton containing human proteins, the retinas of transgenic mice expressing the gene for the human middle-sized neurofilament triplet were investigated at 3 or 12 months of age. Transgenic mice developed tangle-like neurofilamentous accumulations in a subset of retinal ganglion cells at 12 months of age. These neurofilamentous accumulations, which also involved endogenous neurofilament proteins, were present in the perikarya and proximal processes of large ganglion cells and were predominantly located in peripheral retina. The presence of the human protein may thus confer vulnerability of the cytoskeleton to age-related alterations in this specific retinal cell type and may serve as a model for similar cellular changes associated with Alzheimer's disease and glaucoma.

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The most important recent advance in the treatment of neovascular age-related macular degeneration (AMD) is the development of antivascular endothelial growth factor (anti-VEGF) therapeutic agents that preserve and improve visual acuity by arresting choroidal neovascular growth and reducing vascular permeability. Two anti-VEGF agents, ranibizumab and pegaptanib sodium, are currently approved by Swissmedic for the treatment of neovascular AMD. A third anti-VEGF agent, bevacizumab, is currently used as an off label treatment option for exsudative AMD. Other anti-VEGF agent strategies that have shown efficacy include among others, small interfering RNA agents to silence the VEGF gene and receptor and the fusion protein VEGF trap. Anti-VEGF therapies have been used successfully in the clinic, encouraging their use in the treatment of other neovascular and exudative eye diseases.

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BACKGROUND: Pneumonia is the biggest cause of deaths in young children in developing countries, but early diagnosis and intervention can effectively reduce mortality. We aimed to assess the diagnostic value of clinical signs and symptoms to identify radiological pneumonia in children younger than 5 years and to review the accuracy of WHO criteria for diagnosis of clinical pneumonia. METHODS: We searched Medline (PubMed), Embase (Ovid), the Cochrane Database of Systematic Reviews, and reference lists of relevant studies, without date restrictions, to identify articles assessing clinical predictors of radiological pneumonia in children. Selection was based on: design (diagnostic accuracy studies), target disease (pneumonia), participants (children aged <5 years), setting (ambulatory or hospital care), index test (clinical features), and reference standard (chest radiography). Quality assessment was based on the 2011 Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. For each index test, we calculated sensitivity and specificity and, when the tests were assessed in four or more studies, calculated pooled estimates with use of bivariate model and hierarchical summary receiver operation characteristics plots for meta-analysis. FINDINGS: We included 18 articles in our analysis. WHO-approved signs age-related fast breathing (six studies; pooled sensitivity 0·62, 95% CI 0·26-0·89; specificity 0·59, 0·29-0·84) and lower chest wall indrawing (four studies; 0·48, 0·16-0·82; 0·72, 0·47-0·89) showed poor diagnostic performance in the meta-analysis. Features with the highest pooled positive likelihood ratios were respiratory rate higher than 50 breaths per min (1·90, 1·45-2·48), grunting (1·78, 1·10-2·88), chest indrawing (1·76, 0·86-3·58), and nasal flaring (1·75, 1·20-2·56). Features with the lowest pooled negative likelihood ratio were cough (0·30, 0·09-0·96), history of fever (0·53, 0·41-0·69), and respiratory rate higher than 40 breaths per min (0·43, 0·23-0·83). INTERPRETATION: Not one clinical feature was sufficient to diagnose pneumonia definitively. Combination of clinical features in a decision tree might improve diagnostic performance, but the addition of new point-of-care tests for diagnosis of bacterial pneumonia would help to attain an acceptable level of accuracy. FUNDING: Swiss National Science Foundation.

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BACKGROUND: The mean age of acute dengue has undergone a shift towards older ages. This fact points towards the relevance of assessing the influence of age-related comorbidities, such as diabetes, on the clinical presentation of dengue episodes. Identification of factors associated with a severe presentation is of high relevance, because timely treatment is the most important intervention to avert complications and death. This review summarizes and evaluates the published evidence on the association between diabetes and the risk of a severe clinical presentation of dengue. METHODOLOGY/FINDINGS: A systematic literature review was conducted using the MEDLINE database to access any relevant association between dengue and diabetes. Five case-control studies (4 hospital-based, 1 population-based) compared the prevalence of diabetes (self-reported or abstracted from medical records) of persons with dengue (acute or past; controls) and patients with severe clinical manifestations. All except one study were conducted before 2009 and all studies collected information towards WHO 1997 classification system. The reported odds ratios were formally summarized by random-effects meta-analyses. A diagnosis of diabetes was associated with an increased risk for a severe clinical presentation of dengue (OR 1.75; 95% CI: 1.08-2.84, p = 0.022). CONCLUSIONS/SIGNIFICANCE: Large prospective studies that systematically and objectively obtain relevant signs and symptoms of dengue fever episodes as well as of hyperglycemia in the past, and at the time of dengue diagnosis, are needed to properly address the effect of diabetes on the clinical presentation of an acute dengue fever episode. The currently available epidemiological evidence is very limited and only suggestive. The increasing global prevalence of both dengue and diabetes justifies further studies. At this point, confirmation of dengue infection as early as possible in diabetes patients with fever if living in dengue endemic regions seems justified. The presence of this co-morbidity may warrant closer observation for glycemic control and adapted fluid management to diminish the risk for a severe clinical presentation of dengue.

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Resveratrol is a polyphenol that is mainly found in grapes and red wine and has been reported to be a caloric restriction (CR) mimetic driven by Sirtuin 1 (SIRT1) activation. Resveratrol increases metabolic rate, insulin sensitivity, mitochondrial biogenesis and physical endurance, and reduces fat accumulation in mice. In addition, resveratrol may be a powerful agent to prevent age-associated neurodegeneration and to improve cognitive deficits in Alzheimer's disease (AD). Moreover, different findings support the view that longevity in mice could be promoted by CR. In this study, we examined the role of dietary resveratrol in SAMP8 mice, a model of age-related AD. We found that resveratrol supplements increased mean life expectancy and maximal life span in SAMP8 and in their control, the related strain SAMR1. In addition, we examined the resveratrol-mediated neuroprotective effects on several specific hallmarks of AD. We found that long-term dietary resveratrol activates AMPK pathways and pro-survival routes such as SIRT1 in vivo. It also reduces cognitive impairment and has a neuroprotective role, decreasing the amyloid burden and reducing tau hyperphosphorylation.

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Resveratrol is a polyphenol that is mainly found in grapes and red wine and has been reported to be a caloric restriction (CR) mimetic driven by Sirtuin 1 (SIRT1) activation. Resveratrol increases metabolic rate, insulin sensitivity, mitochondrial biogenesis and physical endurance, and reduces fat accumulation in mice. In addition, resveratrol may be a powerful agent to prevent age-associated neurodegeneration and to improve cognitive deficits in Alzheimer's disease (AD). Moreover, different findings support the view that longevity in mice could be promoted by CR. In this study, we examined the role of dietary resveratrol in SAMP8 mice, a model of age-related AD. We found that resveratrol supplements increased mean life expectancy and maximal life span in SAMP8 and in their control, the related strain SAMR1. In addition, we examined the resveratrol-mediated neuroprotective effects on several specific hallmarks of AD. We found that long-term dietary resveratrol activates AMPK pathways and pro-survival routes such as SIRT1 in vivo. It also reduces cognitive impairment and has a neuroprotective role, decreasing the amyloid burden and reducing tau hyperphosphorylation.

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Dopamine (DA) plays a major role in motor and cognitive functions as well as in reward processing by regulating glutamatergic inputs. In particular in the striatum the release of DA rapidly influences synaptic transmission modulating both AMPA and NMDA receptors. Several neurodegenerative and neuropsychiatric disorders, including Parkinson, Huntington and addiction-related diseases, manifest a dysregulation of glutamate and DA signaling. Here, we will focus our attention on the mechanisms underlying the modulation of the glutamatergic transmission by DA in striatal circuits.

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BACKGROUND: The numbers of people attending emergency departments (EDs) at hospitals are increasing. We aimed to analyse trends in ED attendance at a Swiss university hospital between 2002 and 2012, focussing on age-related differences and hospital admission criteria. METHODS: We used hospital administrative data for all patients aged ≥16 years who attended the ED (n = 298,306) at this university hospital between 1 January 2002, and 31 December 2012. We descriptively analysed the numbers of ED visits according to the admission year and stratified by age (≥65 vs <65 years). RESULTS: People attending the ED were on average 46.6 years old (standard deviation 20 years, maximum range 16‒99 years). The annual number of ED attendances grew by n = 6,639 (27.6%) from 24,080 in 2002 to 30,719 in 2012. In the subgroup of patients aged ≥65 the relative increase was 42.3%, which is significantly higher (Pearson's χ2 = 350.046, df = 10; p = 0.000) than the relative increase of 23.4% among patients <65 years. The subgroup of patients ≥65 years attended the ED more often because of diseases (n = 56,307; 85%) than accidents (n = 9,844; 14.9%). This subgroup (patients ≥65 years) was also more often admitted to hospital (Pearson's χ2 = 23,377.190; df = 1; p = 0.000) than patients <65 years. CONCLUSIONS: ED attendance of patients ≥65 years increased in absolute and relative terms. The study findings suggest that staff of this ED may want to assess the needs of patients ≥65 years and, if necessary, adjust the services (e.g., adapted triage scales, adapted geriatric screenings, and adapted hospital admission criteria).

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We investigated trophic ecology variation among colonies as well as sex- and age-related differences in the diet of the southern giant petrel Macronectes giganteus, a long-lived seabird that is sexually dimorphic in size. We measured stable isotopes (δ13C, δ15N) in blood samples collected during breeding at Bird Island (South Georgia, Antarctica) in 1998 and at 2 colonies in the Argentinean area of Patagonia in 2000 and 2001. Individuals from South Georgia showed lower δ13C and δ15N values than those in Patagonia, as expected from the more pelagic location and the short length of the Antarctic food web. Males and females showed significant differences in the isotopic signatures at both localities. These differences agree with the sexual differences in diet found in previous studies, which showed that both sexes rely mainly on penguin and seal carrion, but females also feed extensively on marine prey, such as fish, squid and crustaceans. However, males from Patagonia showed significantly higher δ15N and δ13C values than females did, and the reverse trend was observed at South Georgia. This opposite trend is probably related to the different trophic level of carrion between locations: whereas penguins and pinnipeds in Patagonia rely mainly on fish and cephalopods, in South Georgia they rely mainly on krill. Stable isotope values of male and female chicks in Patagonia did not differ; both attained high values, similar to adult males and higher than adult females, suggesting that parents do not provision their single offspring differently in relation to sex; however, they seem to provide offspring with a higher proportion of carrion, probably of higher quality, and more abundant food, than they consume themselves. Stable isotopes at South Georgia were not affected by age of adults. We have provided new information on intraspecific segregation in the diet in a seabird species and have also underlined the importance of considering food web structure when studying intraspecific variability in trophic ecology.

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The prevalence of obesity and type 2 diabetes has increased at an alarming rate in developed countries. It seems in the light of current knowledge that metabolic syndrome may not develop at all without NAFLD, and NAFLD is estimated to be as common as metabolic syndrome in western population (23 % occurrence). Fat in the liver is called ectopic fat, which is triacylglycerols within the cells of non-adipose tissue. Serum alanine aminotransferase (ALT) values correlate positively with liver fat proportions, and increased activity of ALT predicts type 2 diabetes independently from obesity. Berries, high in natural bioactive compounds, have indicated the potential to reduce the risk of obesity-related diseases. Ectopic fat induces common endocrine excretion of adipose tissue resulting in the overproduction of inflammatory markers, which further induce insulin resistance by multiple mechanisms. Insulin resistance inducing hyperinsulinemia and lipolysis in adipocytes increases the concentration of free fatty acids and consequently causes further fat accumulation in hepatocytes. Polyphenolic fractions of berries have been shown to reverse inflammatory reaction cascades in in vitro and animal studies, and moreover to decrease ectopic fat accumulation. The aim of this thesis was to explore the role of northern berries in obesity-related diseases. The absorption and metabolism of selected berry polyphenols, flavonol glycosides and anthocyanins, was investigated in humans, and metabolites of the studied compounds were identified in plasma and urine samples (I, II). Further, the effects of berries on the risk factors of metabolic syndrome were studied in clinical intervention trials (III, IV), and the different fractions of sea buckthorn berry were tested for their ability to reduce postprandial glycemia and insulinemia after high-glucose meal in a postprandial study with humans (V). The marked impact of mixed berries on plasma ALT values (III), as well as indications of the positive effects of sea buckthorn, its fractions and bilberry on omental adiposity and adhesion molecules (IV) were observed. In study V, sea buckthorn and its polyphenol fractions had a promising effect on potprandial metabolism after high-glucose meal. In the literature review, the possible mechanisms behind the observed effects have been discussed with a special emphasis on ectopic fat accumulation. The literature review indicated that especially tannins and flavonoids have shown potential in suppressing diverse reaction cascades related to systemic inflammation, ectopic fat accumulation and insulin resistance development.

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The general goal of the present work was to study whether spatial perceptual asymmetry initially observed in linguistic dichotic listening studies is related to the linguistic nature of the stimuli and/or is modality-specific, as well as to investigate whether the spatial perceptual/attentional asymmetry changes as a function of age and sensory deficit via praxis. Several dichotic listening studies with linguistic stimuli have shown that the inherent perceptual right ear advantage (REA), which presumably results from the left lateralized linguistic functions (bottom-up processes), can be modified with executive functions (top-down control). Executive functions mature slowly during childhood, are well developed in adulthood, and decline as a function of ageing. In Study I, the purpose was to investigate with a cross-sectional experiment from a lifespan perspective the age-related changes in top-down control of REA for linguistic stimuli in dichotic listening with a forced-attention paradigm (DL). In Study II, the aim was to determine whether the REA is linguistic-stimulus-specific or not, and whether the lifespan changes in perceptual asymmetry observed in dichotic listening would exist also in auditory spatial attention tasks that put load on attentional control. In Study III, using visual spatial attention tasks, mimicking the auditory tasks applied in Study II, it was investigated whether or not the stimulus-non-specific rightward spatial bias found in auditory modality is a multimodal phenomenon. Finally, as it has been suggested that the absence of visual input in blind participants leads to improved auditory spatial perceptual and cognitive skills, the aim in Study IV was to determine, whether blindness modifies the ear advantage in DL. Altogether 180-190 right-handed participants between 5 and 79 years of age were studied in Studies I to III, and in Study IV the performance of 14 blind individuals was compared with that of 129 normally sighted individuals. The results showed that only rightward spatial bias was observed in tasks with intensive attentional load, independent of the type of stimuli (linguistic vs. non-linguistic) or the modality (auditory vs. visual). This multimodal rightward spatial bias probably results from a complex interaction of asymmetrical perceptual, attentional, and/or motor mechanisms. Most importantly, the strength of the rightward spatial bias changed as a function of age and augmented praxis due to sensory deficit. The efficiency of the performance in spatial attention tasks and the ability to overcome the rightward spatial bias increased during childhood, was at its best in young adulthood, and decreased as a function of ageing. Between the ages of 5 and 11 years probably at first develops movement and impulse control, followed by the gradual development of abilities to inhibit distractions and disengage attention. The errors especially in bilateral stimulus conditions suggest that a mild phenomenon resembling extinction can be observed throughout the lifespan, but especially the ability to distribute attention to multiple targets simultaneously decreases in the course of ageing. Blindness enhances the processing of auditory bilateral linguistic stimuli, the ability to overcome a stimulus-driven laterality effect related to speech sound perception, and the ability to direct attention to an appropriate spatial location. It was concluded that the ability to voluntarily suppress and inhibit the multimodal rightward spatial bias changes as a function of age and praxis due to sensory deficit and probably reflects the developmental level of executive functions.

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Free and total carnitine quantification is important as a complementary test for the diagnosis of unusual metabolic diseases, including fatty acid degradation disorders. The present study reports a new method for the quantification of free and total carnitine in dried plasma specimens by isotope dilution electrospray tandem mass spectrometry with sample derivatization. Carnitine is determined by looking for the precursor of ions of m/z = 103 of N-butylester derivative, and the method is validated by comparison with radioenzymatic assay. We obtained an inter- and intra-day assay coefficient of variation of 4.3 and 2.3, respectively. Free and total carnitine was analyzed in 309 dried plasma spot samples from children ranging in age from newborn to 14 years using the new method, which was found to be suitable for calculating reference age-related values for free and total carnitine (less than one month: 19.3 ± 2.4 and 23.5 ± 2.9; one to twelve months: 28.8 ± 10.2 and 35.9 ± 11.4; one to seven years: 30.7 ± 10.3 and 38.1 ± 11.9; seven to 14 years: 33.7 ± 11.6, and 43.1 ± 13.8 µM, respectively). No difference was found between males and females. A significant difference was observed between neonates and the other age groups. We compare our data with reference values in the literature, most of them obtained by radioenzymatic assay. However, this method is laborious and time consuming. The electrospray tandem mass spectrometry method presented here is a reliable, rapid and automated procedure for carnitine quantitation.

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The role of gonadal hormones in induction and, particularly, maintenance/progression of rat thymic involution, which normally starts around puberty, was reassessed by examining the effects of peripubertal orchidectomy on thymic weight and morphometric parameters at different times up to the age of 10 months. Up to 6 months post-castration both thymic weight and cellularity in orchidectomized (Cx) rats were greater than in age-matched control rats, sham Cx (Sx). The increase in thymic cellularity reflected an increase in thymocyte proliferation rate (the proportion of proliferating cells was 18.6 ± 0.7% in 2-month-old Cx (N = 5) vs 13.4 ± 0.3% (N = 5) in age-matched Sx rats) followed by reduced sensitivity to apoptotic signals (apoptotic thymocytes were 9.8 ± 0.9% in 2-month-old Cx (N = 5) vs 15.5 ± 0.3% (N = 5) age-matched Sx rats). However, 9 months post-orchidectomy, neither thymic weight and cellularity nor any of the morphometric parameters analyzed differed between Cx and control rats. The reduction of thymic cellularity in Cx rats to control values may be related to increased sensitivity of their thymocytes to apoptotic signals in culture (72.6 ± 1.2% in 10-month-old vs 9.8 ± 0.9% in 2-month-old Cx rats) followed by reduced responsiveness to proliferative stimuli (14.1 ± 0.2% in 10-month-old vs 18.6 ± 0.7% in 2-month-old Cx rats). Thus, the study indicates that the effects of peripubertal orchidectomy on thymic weight and cellularity, as well as on the main morphometric indices, are long-lasting but not permanent, i.e., that removal of the testes can only postpone but not prevent age-related organ atrophy and consequently functional deterioration of the immune system.