923 resultados para Memory in old age


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The binding of (-)[ 3H ]dihydroalprenolol , an antagonist of norepinephrine , to $-adrenergic receptors in different regions of the brain of male and female rats of various ages was measured . The binding to the synaptosomal fraction of corpus striatum , hypothalamus, cerebral cortex, cerebellum and the brainstems shows a significant decrease in the binding in old rats of both sexes . Only in the female corpus striatal region, the binding in the adult and the old is the same . In the case of females, the highest binding is seen in the young. In the male, an increase in binding occurs up to adulthood , after which it declines, suggesting a definite sex-related difference in the Q-adrenergic receptor.

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The two earliest structures of Minoan Crete that may be considered as large cisterns were both built in the first half of the second millennium BC (the time of the first Minoan palaces) at Myrtos-Pyrgos (lerapetra). A considerable feat of engineering and social management, they remain a most unusual attribute of a Minoan settlement, all the more so since the Myrtos river is/was available to supply water at the foot of the hill of Pyrgos. This paper presents these cisterns, briefly, in terms of geology and technology, the history of their use and re-use, and their relevance to understanding the culture and society (at local and regional levels) of Crete in the time of the Old Palaces, as well as their possible contribution to the political and military history of the period. I then review possible precursors of, and architectural parallels to, the Pyrgos cisterns at Knossos, Malia and Phaistos (none of which has been proved to be a cistern), and the later history of cisterns in Bronze Age Crete. Since only three others are known (at Archanes, Zakro and Tylissos, of Late Bronze Age date), the two cisterns of Myrtos-Pyrgos are an important addition to our still rudimentary knowledge of how the Bronze Age Cretans managed their water supplies.

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Emerging evidence suggests that a group of dietary-derived phytochemicals known as flavonoids are able to induce improvements in memory acquisition, consolidation, storage and retrieval. These low molecular weight polyphenols are widespread in the human diet, are absorbed to only a limited degree and localise in the brain at low concentration. However, they have been found to be highly effective in reversing age-related declines in memory via their ability to interact with the cellular and molecular architecture of the brain responsible for memory. These interactions include an ability to activate signalling pathways, critical in controlling synaptic plasticity, and a potential to induce vascular effects capable of causing new nerve cell growth in the hippocampus. Their ability to activate the extracellular signal-regulated kinase (ERK1/2) and the protein kinase B (PKB/Akt) signalling pathways, leading to the activation of the cAMP response element-binding protein (CREB), a transcription factor responsible for increasing the expression of a number of neurotrophins important in de. ning memory, will be discussed. How these effects lead to improvements in memory through induction of synapse growth and connectivity, increases in dendritic spine density and the functional integration of old and new neurons will be illustrated. The overall goal of this critical review is to emphasize future areas of investigation as well as to highlight these dietary agents as promising candidates for the design of memory-enhancing drugs with relevance to normal and pathological brain ageing (161 references).

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Phytochemical-rich foods have been shown to be effective at reversing age-related deficits in memory in both animals and humans. We show that a supplementation with a blueberry diet (2% w/w) for 12 weeks improves the performance of aged animals in spatial working memory tasks. This improvement emerged within 3 weeks and persisted for the remainder of the testing period. Memory performance correlated well with the activation of cAMP-response element-binding protein (CREB) and increases in both pro- and mature levels of brain-derived neurotrophic factor (BDNF) in the hippocampus. Changes in CREB and BDNF in aged and blueberry-supplemented animals were accompanied by increases in the phosphorylation state of extracellular signal-related kinase (ERK1/2), rather than that of calcium calmodulin kinase (CaMKII and CaMKIV) or protein kinase A. Furthermore, age and blueberry supplementation were linked to changes in the activation state of Akt, mTOR, and the levels of Arc/Arg3.1 in the hippocampus, suggesting that pathways involved in de novo protein synthesis may be involved. Although causal relationships cannot be made among supplementation, behavior, and biochemical parameters, the measurement of anthocyanins and flavanols in the brain following blueberry supplementation may indicate that changes in spatial working memory in aged animals are linked to the effects of flavonoids on the ERK-CREB-BDNF pathway. (c) 2008 Elsevier Inc. All Fights reserved.

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Background: As people age, language-processing ability changes. While several factors modify discourse comprehension ability in older adults, syntactic complexity of auditory discourse has received scant attention. This is despite the widely researched domain of syntactic processing of single sentences in older adults. Aims: The aims of this study were to investigate the ability of healthy older adults to understand stories that differed in syntactic complexity, and its relation to working memory. Methods & Procedures: A total of 51 healthy adults (divided into three age groups) took part. They listened to brief stories (syntactically simple and syntactically complex) and had to respond to false/true comprehension probes following each story. Working memory capacity (digit span, forward and backward) was also measured. Outcomes & Results: Differences were found in the ability of healthy older adults to understand simple and complex discourse. The complex discourse in particular was more sensitive in discerning age-related language patterns. Only the complex discourse task correlated moderately with age. There was no correlation between age and simple discourse. As far as working memory is concerned, moderate correlations were found between working memory and complex discourse. Education did not correlate with discourse, neither simple, nor complex. Conclusions: Older adults may be less efficient in forming syntactically complex representations and this may be influenced by limitations in working memory.

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Older adults often experience memory impairments, but can sometimes use selective processing and schematic support to remember important information. The current experiments investigate to what degree younger and healthy older adults remember medication side effects that were subjectively or objectively important to remember. Participants studied a list of common side effects, and rated how negative these effects were if they were to experience them, and were then given a free recall test. In Experiment 1, the severity of the side effects ranged from mild (e.g., itching) to severe (e.g., stroke), and in Experiment 2, certain side effects were indicated as critical to remember (i.e., “contact your doctor if you experience this”). There were no age differences in terms of free recall of the side effects, and older adults remembered more severe side effects relative to mild effects. However, older adults were less likely to recognize critical side effects on a later recognition test, relative to younger adults. The findings suggest that older adults can selectively remember medication side effects, but have difficulty identifying familiar but potentially critical side effects, and this has implications for monitoring medication use in older age.

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Research has shown that verbal short‐term memory span is shorter in individuals with Down syndrome than in typically developing individuals of equivalent mental age, but little attention has been given to variations within or across groups. Differences in the environment and in particular educational experiences may play a part in the relative ease or difficulty with which children remember verbal material. This article explores the performance of 26 Egyptian pupils with Down syndrome and 26 Egyptian typically developing children on two verbal short‐term memory tests: digit recall and non‐word repetition tasks. The findings of the study revealed that typically developing children showed superior performance on these tasks to that of pupils with Down syndrome, whose performance was both lower and revealed a narrower range of attainment. Comparisons with the performance of children with Down syndrome in this study suggested that not only did the children with Down syndrome perform more poorly than the typically developing children, their profile also appeared worse than the results of studies of children with a similar mental age with Down syndrome carried out in western countries. The results from this study suggested that, while deficits in verbal short‐term memory in Down syndrome may well be universal, it is important to recognise that performances may vary as a consequence of culture and educational experiences. The significance of these findings is explored with reference to approaches to education and how these are conceptualised in relation to children with disabilities.

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Objective: To document meat consumption among 18-month-old children, for use in refining population dietary assessment methods and dietary guidance for young children.

Design: A secondary analysis of data collected in 1998-2000 from the 18 months follow up of the Childhood Asthma Prevention Study: an intervention trial of omega-3 oil supplementation and house-dust mite reduction, from birth to five years.

Subjects and setting: Pregnant women whose unborn children had an atopic family history were recruited from antenatal clinics of six hospitals in western Sydney. Carers of 429 18-month-old children (80% response) satisfactorily completed three-day weighed food records.

Main outcome measures: Mean and median intakes per day and portion sizes of various meats and meat products.

Statistical analyses: T-tests for comparing gender differences; Pearson correlation and one-way analysis of variance for relationships between meat and nutrient intake.

Results: During the recording period 94% of the children ate meat. McDonald's Chicken McNuggetsTM, beef mince, and beef sausages were the most frequently consumed meats. Median portion sizes ranged from 20-50 g, and were considerably smaller than 'usual' portions specified on food frequency questionnaires in common use. Higher meat diets in this age group were not associated with higher intakes of iron or zinc per MJ.

Conclusion: The marginally low intakes of iron and zinc in this age group could be improved by greater use of cuts of red meat appropriately prepared for toddlers.

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Previous research has indicated that the neural processes which underlie working memory change with age. Both age-related increases and decreases to cortical activity have been reported. This study investigated which stages of working memory are most vulnerable to age-related changes after midlife. To do this we examined age-differences in the 13 Hz steady state visually evoked potential (SSVEP) associated with a spatial working memory delayed response task. Participants were 130 healthy adults separated into a midlife (40-60 years) and an older group (61-82 years). Relative to the midlife group, older adults demonstrated greater bilateral frontal activity during encoding and this pattern of activity was related to better working memory performance. In contrast, evidence of age-related under activation was identified over left frontal regions during retrieval. Findings from this study suggest that after midlife, under-activation of frontal regions during retrieval contributes to age-related decline in working memory performance. © 2014 Macpherson, White, Ellis, Stough, Camfield, Silberstein and Pipingas.

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RATIONALE: There is potential for multivitamin supplementation to improve cognition in the elderly. This randomized, double-blind, placebo-controlled trial was conducted to investigate the effects of 16 weeks multivitamin supplementation (Swisse Women's 50+ Ultivite ®) on cognition in elderly women. METHODS: Participants in this study were 56 community dwelling, elderly women, with subjective complaints of memory loss. Cognition was assessed using a computerized battery of memory and attention tasks designed to be sensitive to age-related declines to fluid intelligence, and a measure of verbal recall. Biochemical measures of selected nutrients, homocysteine, markers of inflammation, oxidative stress, and blood safety parameters were also collected. All cognitive and haematological parameters were assessed at baseline and 16 weeks post-treatment. RESULTS: The multivitamin improved speed of response on a measure of spatial working memory, however benefits to other cognitive processes were not observed. Multivitamin supplementation decreased levels of homocysteine and increased levels of vitamin B(6) and B(12), with a trend for vitamin E to increase. There were no hepatotoxic effects of the multivitamin formula indicating this supplement was safe for everyday usage in the elderly. CONCLUSION: Sixteen weeks ssupplementation with a combined multivitamin, mineral and herbal formula may benefit working memory in elderly women at risk of cognitive decline.

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Data comparing age-related alterations in faecal IgA concentrations of dogs are not available in the literature. The present study aimed to compare the faecal concentrations of IgA in puppies, mature and senior dogs. A total of twenty-four beagle dogs were used, including eight puppies (5 months old, four females and four males), eight mature (4.6 years old, eight males) and eight senior dogs (10.6 years old, three males and five females). Fresh faecal samples were collected from each dog for three consecutive days and pooled by animal. After saline extraction, IgA content was measured by ELISA. Data were analysed by one-way ANOVA, and means were compared with Tukey's test (P<0.05). Results showed that puppies have lower faecal IgA concentrations than mature dogs (P<0.05); senior animals presented intermediary results. The reduced faecal IgA concentration in puppies is consistent with the reduced serum and salivary IgA concentrations reported previously, suggesting a reduced mucosal immunity in this age group. Although some studies have found an increased serum IgA concentration in older dogs, this may differ from the intestinal secretion of IgA, which appears to be lower in some senior animals (four of the eight dogs studied).

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O objetivo deste estudo foi verificar as condições periodontais e necessidades de tratamento em crianças e adolescentes, com idades entre 7 e 19 anos, matriculados em Escolas Públicas de Araraquara, SP, Brasil, em 1995, com o propósito de se obter um banco de dados-base inicial para o monitoramento das mudanças no estado periodontal. Uma amostra de 1956 crianças e adolescentes foi examinada por duas examinadoras, previamente calibradas, usando o CPITN. Os resultados mostraram que o sangramento gengival foi a condição periodontal mais frequentemente observada em todas as idades, com média de 3,0 sextantes afetados na idade de 15 anos. A presença de cálculo dental aumentou com a idade. No grupo etário de 15-19 anos, o cálculo dental e as bolsas periodontais rasas (3,5-5,5 mm) foram observados em 39,8% e 1,6% dos adolescentes, respectivamente. Com o propósito de alcançar a meta da OMS de não mais do que um sextante com escores 1 (sangramento) ou 2 (presença de cálculo dental) do CPITN na idade de 15 anos, prioridade deve ser dada aos programas de prevenção primária para que a saúde periodontal da maioria seja beneficiada.

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O objetivo deste estudo foi comparar a prevalência de cárie em crianças de sete a 12 anos em Araraquara, São Paulo, Brasil, em 1989 e 1995. Foi utilizada amostragem sistemática para selecionar crianças de escolas públicas. Examinadores treinados realizaram levantamentos epidemiológicos, utilizando o índice CPOD e os critérios de diagnóstico da OMS. em todas as idades, houve aumento da porcentagem de crianças livres de cárie na dentição permanente (de 29% em 1989 para 51% em 1995). Para crianças aos 12 anos de idade, foram observados índices CPOD de 3,8 em 1989 e de 2,6 em 1995. Detectaram-se também reduções nas porcentagens de crianças classificadas nas seguintes categorias do CPOD: um a três (de 40% em 1989 para 31% em 1995); quatro a seis (de 26,6% em 1989 para 16,5% em 1995) e sete ou mais (de 4,4% em 1989 para 1,5% em 1995). A meta da OMS/FDI para o ano 2000, de que aos 12 anos os indivíduos apresentem em média índice CPOD menor ou igual a três, foi atingida pelos escolares em estudo. Esforços devem ser empreendidos para que haja redução da porcentagem de crianças com experiência de cárie e sejam alcançadas as metas de saúde bucal da OMS/FDI para o ano 2010.

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It is now commonly accepted that chronic inflammation associated with obesity during aging induces insulin resistance in the liver. In the present study, we investigated whether the improvement in insulin sensitivity and insulin signaling, mediated by acute exercise, could be associated with modulation of protein-tyrosine phosphatase 1B (PTP-1B) in the liver of old rats. Aging rats were subjected to swimming for two 1.5-h long bouts, separated by a 45 min rest period. Sixteen hours after the exercise, the rats were sacrificed and proteins from the insulin signaling pathway were analyzed by immunoblotting. Our results show that the fat mass was increased in old rats. The reduction in glucose disappearance rate (Kitt) observed in aged rats was restored 16 h after exercise. Aging increased the content of PTP-1B and attenuated insulin signaling in the liver of rats, a phenomenon that was reversed by exercise. Aging rats also increased the IRβ/PTP-1B and IRS-1/PTP-1B association in the liver when compared with young rats. Conversely, in the liver of exercised old rats, IRβ/PTP-1B and IRS-1/PTP-1B association was markedly decreased. Moreover, in the hepatic tissue of old rats, the insulin signalling was decreased and PEPCK and G6Pase levels were increased when compared with young rats. Interestingly, 16 h after acute exercise, the PEPCK and G6Pase protein level were decreased in the old exercised group. These results provide new insights into the mechanisms by which exercise restores insulin signalling in liver during aging. © 2013 Moura et al; licensee BioMed Central Ltd.

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Rationale Cannabidiol, the main nonpsychotropic constituent of Cannabis sativa, possesses a large number of pharmacological effects including anticonvulsive, sedative, hypnotic, anxiolytic, antipsychotic, anti-inflammatory, and neuroprotective, as demonstrated in clinical and preclinical studies. Many neurodegenerative disorders involve cognitive deficits, and this has led to interest in whether cannabidiol could be useful in the treatment of memory impairment associated to these diseases. Objectives We used an animal model of cognitive impairment induced by iron overload in order to test the effects of cannabidiol in memory-impaired rats. Methods Rats received vehicle or iron at postnatal days 12-14. At the age of 2 months, they received an acute intraperitoneal injection of vehicle or cannabidiol (5.0 or 10.0 mg/kg) immediately after the training session of the novel object recognition task. In order to investigate the effects of chronic cannabidiol, iron-treated rats received daily intraperitoneal injections of cannabidiol for 14 days. Twenty-four hours after the last injection, they were submitted to object recognition training. Retention tests were performed 24 h after training. Results A single acute injection of cannabidiol at the highest dose was able to recover memory in iron-treated rats. Chronic cannabidiol improved recognition memory in iron-treated rats. Acute or chronic cannabidiol does not affect memory in control rats. Conclusions The present findings provide evidence suggesting the potential use of cannabidiol for the treatment of cognitive decline associated with neurodegenerative disorders. Further studies, including clinical trials, are warranted to determine the usefulness of cannabidiol in humans suffering from neurodegenerative disorders.